View DS3101_8880015.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

1 of 149 rev: 061307 note: some revisions of this device may incor porate deviations from published specifications known as erra ta. multiple revisions of any device may be simultaneously available through various sales channel s. for information about device errata, click here: www.maxim-ic.com/errata . general description when paired with an external tcxo or ocxo, the DS3101 is a highly integrated central timing and synchronization solution for sonet/sdh network elements. with 14 input clocks, the device directly accepts both line timing from a large number of line cards and external timing from external ds1/e1 bits transceivers. all input clocks are continuously monitored for frequency accuracy and activity. any two of the input clocks can be selected as the references for the two core dplls. the t0 dpll complies with the stratum 3 and 3e requirements of gr-1244, gr-253, and the requirements of g.812 type iii and g.813. from the output of the core dplls, a wide variety of output clock frequencies and frame pulses can be produced simultaneously on the 11 output clock pins. two DS3101 devices can be configured in a master/slave arrangement for timing card equipment protection. the DS3101 registers and i/o pins are backward compatible with semt ech?s acs8520 and acs8530 timing card ics. the DS3101 is functionally equivalent to a ds3100 without integrated bits transceivers. applications sonet/sdh adms, mspps, and mssps digital cross-connects dslams service provider routers functional diagram features synchronization subsystem for stratum 3e, 3, 4e, and 4, smc and sec - meets requirements of gr-1244 stratum 3/3e, gr-253, g.812 types i, iii, and iv, and g.813 - stratum 3e holdover accuracy with suitable external oscillator - programmable bandwidth, 0.5mhz to 70hz - hitless reference switching on loss of input - phase build-out and transient absorption - locks to and generates 125mhz for gigabit synchronous ethernet per itu-t g.8261 14 input clocks - 10 cmos/ttl inputs accept 2khz, 4khz, and any multiple of 8khz up to 125mhz - two lvds/lvpecl/cmos/ttl inputs accept nx8khz up to 125mhz plus 155.52mhz - two 64khz composite clock receivers - continuous input clock quality monitoring - separate 2/4/8khz frame sync input 11 output clocks - five cmos/ttl outputs drive any internally produced clock up to 77.76mhz - two lvds outputs each drive any internally produced clock up to 311.04mhz - one 64khz composite clock transmitter - one 1.544mhz/2.048mhz output clock - two sync pulses: 8khz and 2khz - output clock rates include 2khz, 8khz, nxds1, nxds2, ds3, nxe1, e3, 6.48mhz, 19.44mhz, 38.88 mhz, 51.84mhz, 62.5mhz, 77.76mhz, 125mhz, 155.52mhz, 311.04mhz internal compensation for master clock oscillator frequency accuracy processor interface: 8-bit parallel or spi serial 1.8v operation with 3.3v i/o (5v tolerant) ordering information part temp range pin-package DS3101gn -40 c to +85 c 256 csbga (17mm) 2 DS3101gn+ -40 c to +85 c 256 csbga (17mm) 2 + denotes a lead-free package. DS3101 stratum 3/3e timing card ic www.maxim-ic.com timing from line cards and bits/ssu receivers (various rates) 14 local tcxo or ocxo 11 timing to line cards and bits/ssu transmitters (various rates) control status DS3101 sonet/sdh synchronization ic
DS3101 stratum 3/3e timing card ic 2 of 149 table of contents 1. standards compli ance ................................................................................................ 6 2. block di agram................................................................................................................. 7 3. application examp le ..................................................................................................... 8 4. detailed d escription .................................................................................................... 8 5. detailed featur es ....................................................................................................... 10 5.1 t0 dpll f eatures .................................................................................................................... 10 5.2 t4 dpll f eatures .................................................................................................................... 10 5.3 i nput c lock f eatures ............................................................................................................. 10 5.4 o utput c lock f eatures .......................................................................................................... 11 5.5 r edundancy f eatures ............................................................................................................. 11 5.6 c omposite c lock i/o f eatures ............................................................................................... 11 5.7 g eneral f eatures ................................................................................................................... 11 6. pin descri ptions............................................................................................................ 12 7. functional description ............................................................................................. 18 7.1 o verview ............................................................................................................................... ... 18 7.2 d evice i dentification and p rotection ................................................................................... 19 7.3 l ocal o scillator and m aster c lock c onfiguration ........................................................... 19 7.4 i nput c lock c onfiguration .................................................................................................... 20 7.4.1 signal format c onfiguration.................................................................................................... ..... 20 7.4.2 frequency conf iguration ........................................................................................................ ...... 22 7.5 i nput c lock q uality m onitoring ............................................................................................ 23 7.5.1 frequency m onitoring........................................................................................................... ........ 23 7.5.2 activity mo nitori ng ............................................................................................................ ............ 23 7.5.3 selected reference ac tivity monitoring ....................................................................................... 24 7.5.4 composite cl ock i nputs ......................................................................................................... ...... 24 7.6 i nput c lock p riority , s election , and s witching .................................................................. 25 7.6.1 priority conf iguration......................................................................................................... ........... 25 7.6.2 automatic select ion algorithm .................................................................................................. ... 25 7.6.3 forced selection ............................................................................................................... ........... 26 7.6.4 ultra-fast refere nce switching................................................................................................. ... 26 7.6.5 external referenc e switchi ng mode ............................................................................................ 26 7.6.6 output clock phase continuity during referenc e switching ...................................................... 27 7.7 dpll a rchitecture and c onfiguration ................................................................................ 27 7.7.1 t0 dpll stat e machine .......................................................................................................... ..... 27 7.7.2 t4 dpll stat e machine .......................................................................................................... ..... 30 7.7.3 bandwidth...................................................................................................................... ............... 31 7.7.4 damping factor ................................................................................................................. ........... 32 7.7.5 phase dete ctors................................................................................................................ ........... 32 7.7.6 loss of phase loc k detection................................................................................................... ... 33 7.7.7 phase monitor and phase bu ild-out............................................................................................ 34 7.7.8 input to output phase adju stment ............................................................................................... 35 7.7.9 phase recali bration ............................................................................................................ ......... 35 7.7.10 frequency and p hase measurement ........................................................................................... 35 7.7.11 input wander and ji tter tole rance .............................................................................................. . 36 7.7.12 jitter and wander transfer..................................................................................................... ...... 36 7.7.13 output jitte r and w ander ....................................................................................................... ...... 37 7.8 o utput c lock c onfiguration ................................................................................................. 38 7.8.1 signal format c onfiguration.................................................................................................... ..... 39
DS3101 stratum 3/3e timing card ic 3 of 149 7.8.2 frequency conf iguration ........................................................................................................ ...... 39 7.9 e quipment r edundancy c onfiguration ................................................................................. 48 7.9.1 master-slave pin feat ure....................................................................................................... ...... 49 7.9.2 master-slave output clock phase alignment .............................................................................. 49 7.9.3 master-slave frame and multiframe alignment with the sync2k pin........................................ 50 7.10 c omposite c lock r eceivers and t ransmitter ...................................................................... 52 7.10.1 ic1 and ic2 re ceivers .......................................................................................................... ....... 53 7.10.2 oc8 transm itter ................................................................................................................ ........... 53 7.11 m icroprocessor i nterfaces .................................................................................................. 55 7.11.1 parallel interf ace modes....................................................................................................... ........ 55 7.11.2 spi interf ace m ode............................................................................................................. .......... 55 7.12 r eset l ogic .............................................................................................................................. 57 7.13 p ower -s upply c onsiderations .............................................................................................. 58 7.14 i nitialization ............................................................................................................................. 58 8. register desc riptions ............................................................................................... 59 8.1 s tatus b its ............................................................................................................................... 59 8.2 c onfiguration f ields .............................................................................................................. 59 8.3 m ultiregister f ields ............................................................................................................... 59 8.4 r egister d efinitions ............................................................................................................... 60 9. jtag test access port and bound ary scan.................................................... 125 9.1 jtag d escription .................................................................................................................. 125 9.2 jtag tap c ontroller s tate m achine d escription ........................................................... 126 9.3 jtag i nstruction r egister and i nstructions .................................................................... 128 9.4 jtag t est r egisters ............................................................................................................ 129 10. electrical ch aracteris tics.................................................................................. 130 10.1 dc c haracteristics .............................................................................................................. 130 10.2 i nput c lock t iming ................................................................................................................. 134 10.3 o utput c lock t iming ............................................................................................................. 134 10.4 p arallel i nterface t iming .................................................................................................... 135 10.5 spi i nterface t iming .............................................................................................................. 138 10.6 jtag i nterface t iming .......................................................................................................... 139 11. pin assign ments .......................................................................................................... 140 12. package in formation ............................................................................................... 145 12.1 256-p in csbga (17 mm x 17 mm ) (56-g6017-001).................................................................... 145 13. thermal in formation................................................................................................ 146 14. glossary ....................................................................................................................... 147 15. acronyms and a bbreviat ions ............................................................................... 148 16. trademark ackn owledgem ents .......................................................................... 148 17. data sheet revisi on history.................................................................................. 149
DS3101 stratum 3/3e timing card ic 4 of 149 list of figures figure 2-1. DS3101 block di agram ............................................................................................... .............................. 7 figure 3-1. typical a pplication example ........................................................................................ ............................. 8 figure 7-1. t0 dpll st ate transition diagram ................................................................................... ...................... 28 figure 7-2. t4 dpll st ate transition diagram ................................................................................... ...................... 31 figure 7-3. typical mtie for t0 dp ll out put .................................................................................... ....................... 37 figure 7-4. typical td ev for t0 dp ll out put .................................................................................... ...................... 38 figure 7-5. dpll block diagram ................................................................................................. .............................. 40 figure 7-6. oc10 8khz options .................................................................................................. .............................. 48 figure 7-7. gr-378 compos ite clock pulse mask.................................................................................. .................. 54 figure 7-8. spi clock pola rity and phas e options............................................................................... ..................... 56 figure 7-9. spi bu s transactions............................................................................................... ............................... 57 figure 9-1. jtag block diagram................................................................................................. ............................ 125 figure 9-2. jtag tap co ntroller stat e machine .................................................................................. .................. 127 figure 10-1. recomm ended termination for lvds pins ............................................................................. ........... 131 figure 10-2. recomm ended termination for lvpec l pins........................................................................... ......... 132 figure 10-3. recomm ended external components for ami composite clock pins ............................................... 133 figure 10-4. parallel interface timing diagram (n onmultiplexed) ................................................................ .......... 136 figure 10-5. parallel interface timing diagram (multipl exed) ................................................................... .............. 137 figure 10-6. spi inte rface timi ng diagram ...................................................................................... ....................... 138 figure 10-7. jtag timing diagram............................................................................................... .......................... 139 figure 11-1. DS3101 pin assignment?left half ................................................................................... ................. 143 figure 11-2. DS3101 pin a ssignment?right half.................................................................................. ................ 144
DS3101 stratum 3/3e timing card ic 5 of 149 list of tables table 1-1. applicab le telecom standards........................................................................................ ........................... 6 table 6-1. input clo ck pin desc riptions ........................................................................................ ............................ 12 table 6-2. output cl ock pin descriptions....................................................................................... ........................... 13 table 6-3. global pin descri ptions ............................................................................................. ............................... 14 table 6-4. parallel inte rface pin de scriptions ................................................................................. .......................... 15 table 6-5. spi bus m ode pin desc riptions ....................................................................................... ........................ 16 table 6-6. jtag inte rface pin de scriptions ..................................................................................... ......................... 16 table 6-7. general-purpose i/o pin de scriptions ................................................................................ ..................... 16 table 6-8. power-supp ly pin descriptions ....................................................................................... ......................... 17 table 7-1. gr-1244 stratum 3e /3 stability r equirements......................................................................... ............... 19 table 7-2. input clock capab ilities ............................................................................................ ................................ 21 table 7-3. locking frequency modes ............................................................................................. .......................... 22 table 7-4. default i nput clock pr iorities ...................................................................................... .............................. 25 table 7-5. damping factors and peak jitter/ wander gain......................................................................... .............. 32 table 7-6. t0 adaptation for t4 phase meas urement mode ......................................................................... ........... 36 table 7-7. output clock capab ilities ........................................................................................... .............................. 38 table 7-8. digital1 and digital2 frequencies................................................................................... .......................... 41 table 7-9. apll frequency to output frequencie s (t0 and t4) .................................................................... .......... 42 table 7-10. t0 apll frequency to t0 path c onfiguration ......................................................................... .............. 42 table 7-11. t4 apll frequency to t4 path c onfiguration ......................................................................... .............. 43 table 7-12. oc1 to oc7 out put frequency selection .............................................................................. ................ 44 table 7-13. possible fre quencies for oc 1 to oc7 ................................................................................ ................... 44 table 7-14. equipment redundancy me thodology ................................................................................... ................ 48 table 7-15. composit e clock variations ......................................................................................... .......................... 52 table 7-16. gr-378 composite cl ock interface sp ecificat ion ..................................................................... ............. 54 table 7-17. g.703 synchronizatio n interfaces sp ecification..................................................................... ................ 54 table 7-18. microproce ssor interfac e modes ..................................................................................... ....................... 55 table 8-1. top-lev el memory map................................................................................................ ............................ 59 table 8-2. re gister map ........................................................................................................ .................................... 60 table 9-1. jtag in struction codes .............................................................................................. ........................... 128 table 9-2. jt ag id code ........................................................................................................ ................................ 129 table 10-1. recommended dc operating conditions ................................................................................ ............ 130 table 10-2. dc ch aracteristics................................................................................................. ............................... 130 table 10-3. cm os/ttl pins ...................................................................................................... ............................. 131 table 10-4. lvds pins .......................................................................................................... .................................. 131 table 10-5. lvpecl pins........................................................................................................ ................................ 132 table 10-6. ami comp osite clock pins ........................................................................................... ........................ 133 table 10-7. recommended external components for out put cloc k oc8.............................................................. 133 table 10-8. input clock timing................................................................................................. ............................... 134 table 10-9. input clock to output cl ock delay .................................................................................. ..................... 134 table 10-10. output clock phase ali gnment, frame sync alignment mode......................................................... 134 table 10-11. paralle l interfac e timing......................................................................................... ............................ 135 table 10-12. spi interface timing .............................................................................................. ............................. 138 table 10-13. jtag interface timing............................................................................................. ........................... 139 table 11-1. pin assignment s sorted by signal name.............................................................................. ............... 140 table 13-1. thermal proper ties, natural convection ............................................................................. ................. 146
DS3101 stratum 3/3e timing card ic 6 of 149 1. standards compliance table 1-1. applicable telecom standards specification specification title ansi t1.101 synchronization interface standard , 1999 t1.102 digital hierarchy?electrical interfaces , 1993 tia/eia-644-a electrical characteristics of low voltage di fferential signaling (lvds) interface circuits, 2001 etsi en 300 417-6-1 transmission and multiplexing (tm); generic requirements of transport functionality of equipment; part 6-1: synchronization layer functions , v1.1.3 (1999-05) en 300 462-3-1 transmission and multiplexing (tm); generic requirements for synchronization networks; part 3-1: the control of jitter and wander within synchronization networks , v1.1.1 (1998-05) en 300 462-5-1 transmission and multiplexing (tm); generic requirements for synchronization networks; part 5-1: timing characteristics of slave clo cks suitable for operation in synchronous digital hierarchy (sdh) equipment , v1.1.1 (1998-05) ieee ieee 1149.1 standard test access port and boundary-scan architecture , 1990 itu-t g.781 synchronization layer functions (06/1999) g.783 itu g.783 characteristics of synchronous digi tal hierarchy (sdh) equipment functional blocks (10/2000 plus amendment 1 06/2002 and corrigendum 2 03/2003) g.812 timing requirements of slave clocks suitable for use as node clocks in synchronization networks (06/1998) g.813 timing characteristics of sdh equipment slave clocks (sec) (03/2003) g.823 the control of jitter and wander within digital networks which are based on the 2048kbps hierarchy (03/2000) g.824 the control of jitter and wander within digital networks which are based on the 1544kbps hierarchy (03/2000) g.825 the control of jitter and wander within digital networks which are based on the synchronous digital hierarchy (sdh) (03/2000) telcordia gr-253-core sonet transport systems: common generic criteria , issue 3, september 2000 gr-378-core generic requirements for timing signal generators , issue 2, february 1999 gr-1244-core clocks for the synchronized ne twork: common generic criteria, issue 2, december 2000
DS3101 stratum 3/3e timing card ic 7 of 149 2. block diagram figure 2-1. DS3101 block diagram t0 dpll master clock generator oc1 oc2 oc3 oc4 oc5 oc7 pos/neg oc6 pos/neg oc8 pos/neg oc9 oc10 oc11 ic1 ic2 ic3 ic4 ic5 pos/neg ic7 ic6 pos/neg ic8 ic9 ic10 ic11 ic12 microprocessor port (8-bit parallel or spi serial) and hw control and status pins tcxo or ocxo rst ifsel[2:0] cs wr / r/ w rd / ds ale a[8:0] ad[5:3] ad6 / cpha ad7 / cpol ad2 / sclk ad1 / sdi ad0 / sdo intreq ic13 ic14 t4 dpll hiz mastslv sonsdh srcsw rdy sync2k refclk gpio[4:1] wdt wdt srfail cc rx input clock selector, divider and monitor cc rx ic1a ic2a output clock synthesizer and selector cc tx jtag jtrst jtms jtclk jtdi jtdo DS3101
DS3101 stratum 3/3e timing card ic 8 of 149 3. application example figure 3-1. typical application example ds3100 to bits/ssu tcxo or ocxo monitor, divider, selector t4 dpll t4 apll bits tx bits tx t0 dpll monitor, divider, selector bits rx bits rx micro controller timing card (1 of 2) backplane ds1, e1 or 2048 khz ds1, e1 or 2048 khz from bits/ssu timing card (2 of 2) identical to timing card 1 t0 apll line card (1 of n) line card (n of n) <1> <1> <1> <1> n typically 19.44 mhz point-to-point or multidrop buses create derived ds1 or e1/2048 khz clock from 19.44 mhz frequency locked to line clock create ds1/e1 frames, insert ssms, transmit ds1, e1 or 2048 khz sync signal activty and frequency monitoring, select highest priority valid input clock/data recovery, equalizer, framer, extract ssms stratum 3 or 3e: jitter/wander filtering, hitless switching, phase adjust, holdover divide line clock down to backplane rate, send to timing cards select best system clock, hitless switching, basic holdover dpll apll clock multiplication, jitter cleanup to port serdes n <0> n n <0> 4. detailed description figure 2-1 illustrates the blocks described in this secti on and how they relate to one another. section 5 provides a detailed feature list. the DS3101 is a highly integrated timing card ic for systems with sonet/sdh ports. at t he core of this device are two digital phase-locked loops (dplls) labeled t0 and t4 1 . dpll technology makes uses of digital-signal processing (dsp) and digital-frequency synthesis (dfs) tec hniques to implement plls that are precise, flexible, and have consistent performance over voltage, temperature, and manufacturing process variations. the DS3101?s dplls are digitally configurable for input and output freque ncies, loop bandwidth, damping factor, pull-in/hold-in range, and a variety of other factors. both dplls can di rectly lock to many common telecom frequencies and also can lock at 8khz to any multiple of 8khz up to 155.52m hz. the dplls can also tolerate and filter significant amounts of jitter and wander. 1 these names are adapted from output ports of the sets function s pecified in itu and etsi standards such as etsi en 300 462-2-1.
DS3101 stratum 3/3e timing card ic 9 of 149 the t0 dpll is responsible for generating the system clo cks used to time the outgoing traffic interfaces of the system (sonet/sdh, synchronous ethernet, etc.). to perfo rm this role in a variety of systems with diverse performance requirements, the t0 dpll has a sophistic ated feature set and is highly configurable. t0 can automatically transition among free-run, lo cked and holdover states all without software intervention. in free-run, t0 generates a stable, low-noise clock with the same frequency accuracy as the external oscillator connected to the refclk pin. with software calibration the ds 3101 can even improve the accuracy to within 0.02 ppm. when an input reference has been validated, t0 transitions to the lo cked state in which its output clock accuracy is equal to the accuracy of the input reference. while in the lock ed state, t0 acquires a high-accuracylong-term average frequency value to use as the holdover frequency. when its selected reference fails, t0 can very quickly detect the failure and enter the holdover state to avoid affecting its out put clock. from holdover it can automatically switch to the next highest priority input reference, again without a ffecting its output clock (hit less switching). switching among input references can be either revertive or nonrevertive. when all input references are lost, t0 stays in holdover in which it generates a stable low-noise clock with initial frequency accuracy equal to its stored holdover value and drift performance determined by the quality of the external oscillator. with a suitable local oscillator the t0 dpll provides holdover performance suitable for all applications up to and including stratum 3e. t0 can also perform phase build-outs and fine-granular ity output clock phase adjustments. the t4 dpll has a much less demanding role to play and therefore is much simpler than t0. often t4 is used as a frequency converter to create a derived ds1- or e1 -rate clock (frequency locked to an incoming sonet/sdh port) to be sent to a nearby bits timing signal generato r (tsg, telcordia terminology) or synchronization supply unit (ssu, itu-t terminology). in other cases t4 is phase-locked to t0 and used as a frequency converter to produce additional output clock rates for use within the system, such as nxds1, nx e1, nxds2, ds3, e3, or 125mhz for synchronous ethernet. t4 can also be configured as a measuring tool to measure the frequency of an input reference or the phase difference between two input references. at the front end of both the t0 and t4 dplls is the input clock selector, divi der, and monitor (icsdm) block. this block continuously monitors as many as 14 different input clocks of various frequencies for activity and frequency accuracy. in addition, icsdm maintains separate input cl ock priority tables for the t0 and t4 dplls and can automatically select and provide the hi ghest priority valid clock to each dpll without any software intervention. the icsdm block can also divide the selected cl ock down to 8khz if required by the dpll. in addition to digital clock signals from system line card s, the DS3101 can also direct ly receive up to two 64khz composite clock signals on its ic1a and ic2a pins. these signals typically come from a nearby bits timing signal generator or ssu to provide external timing to the system. the output clock synthesizer and selector (ocss) block shown in figure 2-1 contains the t0 output apll, the t4 output apll, clock divider logic, and additional output dfs blocks. the t0 and t4 aplls multiply the clock rates from the dplls by four and simulataneously attenuate jitte r. using the different settings of the t0 and t4 dplls and the output divider logic, the DS3101 can produce more than 60 different output frequencies including common sonet/sdh, pdh and synchronous ethernet ra tes plus 2khz and 8khz frame pulses. in addition to creating digital clock signals for use within the system, the DS3101 can al so directly transmit one composite clock signal on its oc8 pin. this signal typi cally conveys the recovered timing from one sonet/sdh port to a nearby bits timing-signal generator or ssu which in turn distributes timing to the whole central office. the entire chip is clocked from the external oscillat or connected to the refclk pin. thus the free-run and holdover stability of the DS3101-based timing card is entirely a function of the stability of the external oscillator, the performance of which can be selected to match the application: tcxo, ocxo, double-oven ocxo, etc. the 12.8mhz clock from the external oscillator is multiplied by sixteen by the master clock generator block to create the 204.8mhz master clock used by the rest of the devi ce. since every block on the device depends on the master clock and therefore the local oscillator clock for proper operation, the master clock generat or has a watchdog timer (wdt) function that can be used to signal a local micropro cessor in the event of a local oscillator clock failure. the DS3101 also has several features to support master/slave timing card redundancy and protection. two DS3101 devices on redundant cards can be configured to mainta in the same priority tables, choose the same input references, and generate output clocks and frame syncs with the same frequency and phase.
DS3101 stratum 3/3e timing card ic 10 of 149 5. detailed features 5.1 t0 dpll features high-resolution dpll plus low-jitter output apll sophisticated state machine autom atically transitions between free-run, locked, and holdover states revertive or nonrevertive reference selection algorithm programmable bandwidth in 18 steps from 0.5mhz to 70hz separately configurable acquisition bandwidth and locked bandwidth programmable damping factor to balance lock time with peaking: 1.2, 2.5, 5, 10, or 20 multiple phase detectors: phase/fr equency, early/late, and multicycle phase/frequency locking ( 360 capture) or nearest-edge phase locking ( 180 capture) multicycle phase detection and locking (up to 8191ui) improves jitter tolerance and lock time phase build-out in response to input phase transients (1 to 3.5 s) phase build-out in response to reference switching less than 5ns output clock phase transient during phase build-out output phase adjustment up to 200ns in 6ps steps with respect to selected input reference high-resolution frequency and phase measurement holdover frequency averaging wi th 8- or 110-minute intervals apll frequency options suitable for n x 19.44mhz, n x ds1, and n x e1 low-jitter frame sync (8khz) and multifra me sync (2khz) outputs on oc10 and oc11 2khz and 8khz clocks available on oc1 through oc7 with programmable polarity and pulse width 5.2 t4 dpll features high-resolution dpll plus low-jitter output apll programmable bandwidth: 18hz, 35hz, or 70hz programmable damping factor to balance lock time with peaking: 1.2, 2.5, 5, 10, or 20 multiple phase detectors: phase/fr equency, early/late, and multicycle phase/frequency locking ( 360 capture) or nearest-edge phase locking ( 180 capture) multicycle phase detection and locking (up to 8191ui) improves jitter tolerance and lock time apll frequency options suitable for n x 19.44mhz, n x ds 1, n x e1, ds3, e3, 6312khz, and n x 62.5mhz (for gigabit ethernet) 2khz and 8khz clocks available on oc1 through oc7 with programmable polarity and pulse width can operate independently or locked to t0 dpll phase detector can be used to measure phase difference between two input clocks 5.3 input clock features 14 input clocks 10 programmable-frequency cmos/ttl input clocks accept any multiple of 8khz up to 125mhz two lvds/lvpecl/cmos/ttl input clocks accept any multiple of 8khz up to 125mhz plus 155.52mhz two 64khz composite clock receivers (ami format) that can also be configured as programmable-frequency cmos/ttl input clocks if needed all 14 input clocks are constantly m onitored by programmable frequency monitors and activity monitors fast activity monitor can disqualify the sele cted reference after two missing clock cycles separate 2/4/8khz sync input
DS3101 stratum 3/3e timing card ic 11 of 149 5.4 output clock features 11 output clocks five programmable-frequency cmos/ttl output clocks drive any internally produced clock up 77.76mhz two programmable-frequency lvds output clocks driv e any internally produced clock up to 311.04mhz two sync pulses, 2khz and 8khz, can be di sciplined by a 2khz or 8khz sync input one 1.544mhz/2.048mhz output clock one 64khz composite clock output (ami format) output clock rates include 2khz, 8khz, nxds1, nxds2, ds3, nxe1, e3, 19.44mhz, 38.88mhz, 51.84mhz, 62.5mhz, 77.76mhz, 125.0mhz, 155.52mhz, and 311.04mhz outputs at even divisors of 311.04mhz have less than 0.5ns peak-to-peak output jitter 5.5 redundancy features devices on redundant timing cards can be configured for master/slave operation clocks and frame syncs can be cross-wired between dev ices to ensure that slave always tracks master master/slave mode pin can auto-configure slave to tra ck master with no phase build-out and wider bandwidth input clock priority tables can easily be kept synchronized between master and slave 5.6 composite clock i/o features two composite clock receivers and one composite clock transmitter (all ami format) compliant with telcordia gr-378 composite clock, g. 703 centralized clock, and g.703 appendix ii.1 japanese synchronization interfaces configurable for 50% or 5/8 duty cycl e, 1v or 3v pulse amplitude, and 110 /120 /133 termination received signals are monitored for los, ami violat ions, presence/absence of the 8 khz component, and presence/absence of the 400hz component (for g.7 03 appendix ii.1 option b) transmitter can generate or suppress the 8khz compone nt and/or the 400 hz component (for g.703 appendix ii.1 option b) composite clock receiver inputs can be configured as programmable-frequency cmos/ttl inputs if composite clock support is not needed 5.7 general features operates from a single external 12.80 0mhz local oscillator (tcxo or ocxo) on-chip local oscillator watchdog circuit microprocessor interface can be 8-bit pa rallel (intel or motorola, multiplexed or nonmultiplexed) or spi serial register set can be write-protected
DS3101 stratum 3/3e timing card ic 12 of 149 6. pin descriptions table 6-1. input clo ck pin descriptions pin name (1) type (2) function h1 refclk i reference clock. connect to a 12.800mhz, high-accuracy, high-stability, low-noise local oscillator (tcxo or ocxo). see section 7.3 . p6 ic1a i input clock 1 ami. ami 64khz composite clock. enabled when mcr5 :ic1sf = 0. see section 7.10.1 , table 10-6 , and figure 10-3 . a10 ic1 i pd input clock 1. cmos/ttl. programmable frequency (d efault 8khz). enabled when mcr5 :ic1sf = 1. see section 7.10.1 . p7 ic2a i input clock 2 ami. ami 64khz composite clock. enabled when mcr5 :ic2sf = 0. see section 7.10.1 , table 10-6 , and figure 10-3 . b10 ic2 i pd input clock 2. cmos/ttl. programmable frequency (d efault 8khz). enabled when mcr5 :ic2sf = 1. see section 7.10.1 . c10 ic3 i pd input clock 3. cmos/ttl. programmable fr equency (default 8khz). a11 ic4 i pd input clock 4. cmos/ttl. programmable fr equency (default 8khz). b5 ic5pos a5 ic5neg i a , i a input clock 5. lvds/lvpecl. programmable freque ncy (default 19.44mhz lvds). lvds: see table 10-4 and figure 10-1 . lvpecl: see table 10-5 and figure 10-2 . b4 ic6pos a4 ic6neg i a , i a input clock 6. lvds/lvpecl. programmable fr equency (defau lt 19.44mhz lvpecl). lvds: see table 10-4 and figure 10-1 . lvpecl: see table 10-5 and figure 10-2 . b11 ic7 i pd input clock 7. cmos/ttl. programmable frequ ency (default 19.44mhz). c11 ic8 i pd input clock 8. cmos/ttl. programmable frequ ency (default 19.44mhz). a12 ic9 i pd input clock 9. cmos/ttl. programmable frequ ency (default 19.44mhz). b12 ic10 i pd input clock 10. cmos/ttl. programmable frequency (default 19.44mhz). a13 ic11 i pd input clock 11. cmos/ttl. programmable frequency (default 19.44mhz in master mode, 6.48mhz in slave mode). c12 ic12 i pd input clock 12. cmos/ttl. programmable frequency (default 1.544/2.048mhz). b13 ic13 i pd input clock 13. cmos/ttl. programmable frequency (default 1.544/2.048mhz). a14 ic14 i pd input clock 14. cmos/ttl. programmable frequency (default 1.544/2.048mhz). b14 sync2k i pd frame sync input. 2khz, 4khz, or 8khz.
DS3101 stratum 3/3e timing card ic 13 of 149 table 6-2. output cl ock pin descriptions pin name (1) type (2) function c6 oc1 o 3 output clock 1. cmos/ttl. programmable fr equency (default 6.48mhz). a7 oc2 o 3 output clock 2. cmos/ttl. programmable frequency (default 38.88mhz). b7 oc3 o 3 output clock 3. cmos/ttl. programmable frequency (default 19.44mhz). c7 oc4 o 3 output clock 4. cmos/ttl. programmable frequency (default 38.88mhz). a8 oc5 o 3 output clock 5. cmos/ttl. programmable frequency (default 77.76mhz). b3 oc6pos a3 oc6neg o 3 output clock 6. lvds. programmable frequency ( default 38.88mhz lvds). see table 10-4 and figure 10-1 . c2 oc7pos c1 oc7neg o 3 output clock 7. lvds. programmable frequency ( default 19.44mhz lvds). see table 10-4 and figure 10-1 . c8 oc8pos b8 oc8neg o 3 output clock 8. ami. 64khz composite clock. see section 7.10.2 , table 10-6 , and figure 10-3 . a9 oc9 o 3 output clock 9. cmos/ttl. 1.544/2.048mhz. b9 oc10 o 3 output clock 10. cmos/ttl. 8khz frame sync or clock. c9 oc11 o 3 output clock 11. cmos/ttl. 2khz multiframe sync or clock.
DS3101 stratum 3/3e timing card ic 14 of 149 table 6-3. global pin descriptions pin name (1) type (2) function b6 rst i pu active-low reset. when this global asynchronous reset is pulled low, all internal circuitry is reset to default values. the device is held in reset as long as rst is low. rst should be held low for at least two refclk cycles. r14 hiz i pu acitve-low high-z enable input. the jtrst pin must be low to activate this function. 0 = put all output pins in a high-impedance state 1 = normal operation n1 ifsel0 n2 ifsel1 p1 ifsel2 i pd microprocessor interface select. during reset, the value on these pins is latched into the ifsel field of the ifcr register. see section 7.11 . 010 = intel bus mode (multiplexed) 011 = intel bus mode (nonmultiplexed) 100 = motorola mode (nonmultiplexed) 101 = spi mode (address and data transmitted lsb first) 110 = motorola mode (multiplexed) 111 = spi mode (address and data transmitted msb first) 000, 001 = {unused value} r11 mastslv i pu master/slave select input. sets the state of the mastslv bit in the mcr3 register. 0 = slave mode 1 = master mode m3 sonsdh i pd sonet/sdh frequency select input. sets the reset-default state of the sonsdh bit in mcr3 , the dig1ss and dig2ss bits in mcr6 , and the oc9son bit in t4cr1 . 0 = sdh rates (n x 2.048mhz) 1 = sonet rates (n x 1.544mhz) m2 srcsw i pd source switching. fast source switching control input. see section 7.6.5 . j2 srfail o 3 srfail status. when mcr10 :srfpin = 1, this pin follows t he state of the srfail status bit in the msr2 register. this gives the system a very fast indication of the failure of the current reference. when mcr10 :srfpin = 0, srfail is disabled (low). c5 wdt i a watchdog timer. analog node for the refclk watchdog timer. connect to a resistor (r) to v ddio and a capacitor (c) to ground. suggested values are r = 20k and c = 0.01 f. see section 7.3 .
DS3101 stratum 3/3e timing card ic 15 of 149 table 6-4. parallel interface pin descriptions note: these pins are active in intel and motorola bus modes. see section 7.11.1 for functional description and section 10.4 for timing specifications. pin name (1) type (2) function k14 ale i pd address latch enable. this signal controls the address latch. in nonmultiplexed bus modes, the address is latched from a[8:0]. in these modes, ale is typically wired high to make the latch transparent. in multiplexed bu s modes, the address is latched from a[8] and ad[7:0]. j16 cs i pu active-low chip select. this pin must be asserted (low) to read or write internal registers. j15 wr /r/ w i pu active-low write enable or read/active-low write select. for intel bus modes, wr is asserted to write internal registers. for motorola bus modes, r/ w = 1 indicates a read and r/ w = 0 indicates a write. j14 rd / ds i pu active-low read enable or active-low data strobe. for the intel-style interface modes, rd is asserted (low) to read internal registers. for the motorola-style interface modes, the falling edge of ds enables data output on ad[7:0] during reads while the rising edge of ds latches data from ad[7:0] during writes. e16 a[8] f15 a[7] g14 a[6] f16 a[5] g15 a[4] h14 a[3] g16 a[2] h15 a[1] h16 a[0] i pd address bus. in nonmultiplexed bus modes, these in puts specify the address of the internal register to be accesse d. in multiplexed bus modes, the address is specified on a[8] and ad[7:0], while a[7:0] are not us ed and should be wired high or low. c14 ad[7] d14 ad[6] e14 ad[5] c15 ad[4] d15 ad[3] c16 ad[2] d16 ad[1] e15 ad[0] i/o address/data bus. in both multiplexed and nonmultiplexed bus modes, these pins are an 8-bit data bus. in multiplexed bus modes, t hese pins also convey the lower 8 bits of the register address. b15 rdy o active-low ready/data acknowledge. this pin is asserted when the device has completed a read or write operation. a15 intreq o interrupt request. the behavior of this pin is configured in the intcr register. polarity can be active high or active low. drive action can be push-pull or open drain. the pin can also be configured as a general-purpose output if the interrupt request function is not needed.
DS3101 stratum 3/3e timing card ic 16 of 149 table 6-5. spi bus m ode pin descriptions note: these pins are active in spi interface modes. see section 7.11.2 for functional description and section 10.5 for timing specifications. pin name (1) type (2) function j16 cs i pu active-low chip select. this pin must be asserted to read or write internal registers. c16 sclk i serial clock. sclk is always driven by the spi bus master. d16 sdi i serial data input. the spi bus master transmits dat a to the device on this pin. e15 sdo o serial data output. the device transmits data to the spi bus master on this pin. d14 cpha i clock phase. see section figure 7-8 . 0 = data is latched on the lead ing edge of the sclk pulse 1 = data is latched on the trailing edge of the sclk pulse c14 cpol i clock polarity. see section figure 7-8 . 0 = sclk is normally low and pulses high during bus transactions 1 = sclk is normally high and pulses low during bus transactions a15 intreq o interrupt request. the behavior of this pin is configured in the intcr register. polarity can be active high or active low. drive action can be push-pull or open drain. the pin can also be configured as a general -purpose output if the interrupt request function is not needed. table 6-6. jtag inte rface pin descriptions note: see section 9 for functional description and section 10.6 for timing specifications. pin name (1) type (2) function t8 jtrst i pu active-low jtag test reset. asynchronously resets the test access port (tap) controller. if not used, jtrst can be held low or high. r8 jtclk i jtag clock. shifts data into jtdi on the rising edge and out of jtdo on the falling edge. if not used, jtclk can be held low or high. r9 jtdi i pu jtag test data input. test instructions and data are clocked in on this pin on the rising edge of jtclk. if not used, jtdi can be held low or high. p9 jtdo o jtag test data output. test instructions and data are clocked out on this pin on the falling edge of jtclk. if not used, leave floating. t9 jtms i pu jtag test mode select. sampled on the rising edge of jtclk and is used to place the port into the various defined ieee 114 9.1 states. if not used, connect to v ddio or leave floating. table 6-7. general-purpose i/o pin descriptions pin name (1) type (2) function e2 gpio1 i/o general-purpose i/o pin 1. gpcr :gpio1d configures this pin as an input or an output. gpcr :gpio1o specifies the output value. gpsr :gpio1 indicates the state of the pin. f3 gpio2 i/o general-purpose i/o pin 2. gpcr :gpio2d configures this pin as an input or an output. gpcr :gpio2o specifies the output value. gpsr :gpio2 indicates the state of the pin. h2 gpio3 i/o general-purpose i/o pin 3. gpcr :gpio3d configures this pin as an input or an output. gpcr :gpio3o specifies the output value. gpsr :gpio3 indicates the state of the pin. j1 gpio4 i/o general-purpose i/o pin 4. gpcr :gpio4d configures this pin as an input or an output. gpcr :gpio4o specifies the output value. gpsr :gpio4 indicates the state of the pin.
DS3101 stratum 3/3e timing card ic 17 of 149 table 6-8. power-su pply pin descriptions pin name (1 ) type (2) function d6, d8, d9, d11, e6, e11, f4, f5, f12, f13, h4, h13, j4, j13, l4, l5, l12, l13, m6, m11, n6, n8, n9, n11 v dd p core power supply. 1.8v 10% b1, b16, d7, d10, e7?e10, g4, g5, g12, g13, h5, h12, j5, j12, k4, k5, k12, k13, m7, m8, m9, m10, n7, n10, r1, r16 v ddio p i/o power supply. 3.3v 10% a1, a16, d4, d5, d12, d13, e4, e5, e12, e13, f6?f11, g6?g11, h6?h11, j6?j11, k6?k11, l6?l11, m4, m5, m12, m13, n4, n12, n13, t1, t16 v ss p ground reference a6 vdd_icdiff p power supply for lvds inputs (ic5 and ic6). 3.3v 10% c4 vss_icdiff p return for lvds inputs (ic5 and ic6) b2 vdd_oc6 p power supply for lvds output oc6. 1.8v 10% a2 vss_oc6 p return for lvds output oc6 c3 vdd_oc7 p power supply for lvds output oc7. 1.8v 10% d3 vss_oc7 p return for lvds output oc7 d1 avdd_pll1 p power supply for t0 output apll. 1.8v 10% d2 avss_pll1 p return for t0 output apll e1 avdd_pll2 p power supply for t4 output apll. 1.8v 10% e3 avss_pll2 p return for t4 output apll. f1 avdd_pll3 p power supply for t0 feedback apll. 1.8v 10% g2 avss_pll3 p return for t0 feedback apll g1 avdd_pll4 p power supply for master clock generator apll. 1.8v 10% g3 avss_pll4 p return for master clock generator apll tm1 r13 tm2 t15 ? connect to v ss c13, f2, f14, j3, k1, k2, k3, k15, k16, l1, l2, l3, l14, l15, l16, m1, m14, m15, m16, n14, n15, n16, p2, p3, p4, p5, p8, p12, p13, p14, p15, p16, r2, r3, r4, r5, r6, r7, r13, r15, t2, t3, t4, t5, t6, t7, t15 n.c. ? noconnection note 1: all pin names with an overbar (e.g., cs ) are active low. note 2: all pins, except power and analog pi ns, are cmos/ttl, unless otherwise specified in the pin description. i = input pin o = output pin
DS3101 stratum 3/3e timing card ic 18 of 149 i a = analog input pin o a = analog output pin (can be placed in a high-impedance state) i pd = input pin with internal 50k pulldown o 3 = output pin that can tri-stated (i.e., placed in a high-impedance state) i pu = input pin with internal 50k pullup to approx.2.2v p = power-supply pin i/o = input/output pin note 3: all digital pins are i/o pins in jtag mode. note 4: when ramping power supplies up or down, the voltage on any 1.8v power supply pin must not exceed the voltage on any 3.3v power- supply pin. 7. functional description 7.1 overview the DS3101 has 14 input clocks and 11 output clocks,. ther e are two separate dpll paths in the device: the high- performance t0 path and the simpler t4 path. see figure 2-1 . two of the 14 input clocks are 64 khz composite cloc k receivers (by default), two are lvds/lvpecl, and 10 are cmos/ttl (5v tolerant). the composit e clock receivers can be converted to cmos/ttl inputs as needed. the cmos/ttl inputs can accept signals from 2khz to 125mhz . the lvds/lvpecl pins can accept clock signals up to 155.52mhz. each input clock can be monitored continually for activi ty and/or frequency. frequency can be compared to both a hard limit and a soft limit. inputs outside the hard limit are declared invalid, while inputs inside the hard limit but outside the soft limit are merely flagged. each input can be marked unavailable or given a priority number. separate input priority numbers are maintained for the t0 dpll and the t4 dpll. except in special modes, the highest priority valid input is automatically selected as the reference for each path. both the t0 and t4 dplls can directly lock to many co mmon telecom frequencies, including, but not limited to 8khz, ds1, e1, 19.44mhz, and 38.88mhz. the dplls can al so lock to any multiple of 8khz up to 125mhz. the t0 dpll is the high-performance path with all the features for node timing synchronization. the t4 dpll is a simpler auxiliary path typically used to provide derived ds1s, e1s, or other synchronization signals to an external bits/ssu. the two paths can be operated independently or locked together. both dplls have these features: automatic reference selection based on input quality and priority optional manual reference selection/forcing configurable quality thresholds for each input adjustable pll characteristics, including bandwidth, pull-in range, and damping factor ability to lock to several common telecom frequencies plus multiples of 8khz up to 155.52mhz frequency conversion between input and out put using digital frequency synthesis combined performance of a stable, consistent digital pll and a low-jitter analog output pll the t0 dpll has these additional feat ures not available in the t4 dpll: a full state machine for automatic transitions among free-run, locked, and holdover states nonrevertive reference switching mode phase build-out for reference switching (?hitless?) and for phase hits on the selected reference output vs. input phase offset control 18 bandwidth selections from 0.5mhz to 70h z (vs. three selections for the t4 path) noise rejection circuitry for low-frequency references optional software control over holdover frequency output phase alignment to input frame sync signal several frequency averaging methods for acquiring the holdover frequency the t4 dpll has these additional feat ures not available in the t0 dpll: optional mode to lock to the t0 dpll
DS3101 stratum 3/3e timing card ic 19 of 149 optional mode to measure the phase difference between two input clocks ability to generate ds3, e3, 6312khz, and n x 62.5mhz (gigabit ethernet) frequencies typically the internal state machine cont rols the t0 dpll, but manual control by system software is also available. the t4 dpll has a simpler state machine that software cannot directly control. in either dpll, however, software can override the dpll logic using manual reference selection. the t0 dpll always operates at 77.76mhz, regardless of the output frequencies sele cted for the output clock pins. the t4 dpll can operate at any of several frequencies in order to support generation of frequencies such as 44.736mhz (ds3) and 34.368mhz (e3). when the t4 dpll is lo cked to the t0 dpll, it locks to an 8khz signal from t0 to ensure synchronization of all possible t4 frequencies, which are always multiples of 8khz. the outputs of the t0 and t4 dplls are connected to hi gh-speed aplls that multiply the dpll clock rate and filter dpll output jitter. the outputs of the aplls are divided down to make a wide variety of possible frequencies available at the output clock pins. all or some of the output frequencies of the t0 dpll can be synchronized to an input 2khz, 4khz, or 8khz sync signal (sync2k pin). this synchronization to a low-frequency input enables, among other things, two redundant timing cards to maintain output phase alignment with one another. seven of the output clocks can be configured for a variety of different frequencies from either the t0 dpll or the t4 dpll. one output clock is a 64khz composite clock transmitter (ami form at), one is 1544khz or 2048khz, one is 8khz, and one is 2khz. of the seven multifrequency out puts, five are cmos/ttl and two are lvds. altogether more than 60 output frequencies are possible, ranging from 2khz to 311.04mhz. 7.2 device identificat ion and protection the 16-bit read-only id field in the id1 and id2 registers is set to 0c1dh = 3101 decimal. the device revision can be read from the rev register. contact the factory to interpret th is value and determine the latest revision. the register set can be protected from inadvertent writes using the prot register. 7.3 local oscillator and m aster clock configuration the t0 and t4 dpll paths operate from a 204.8mhz mast er clock. the master clo ck is synthesized from a 12.800mhz clock originating from a local oscillator attached to the refclk pin. the st ability of the t0 dpll in holdover is equivalent to the stability of the local oscillator. select ion of an appropriate loca l oscillator is, therefore, of crucial importance if the telecom standards listed in table 1-1 are to be met. tcxos can be used in less stringent cases, but ocxos are required in the mo st demanding applications. even ocxos may need to be shielded to avoid slow frequen cy changes due to ambient temperature fluc tuations and drift. careful evaluation of the local oscillator component is necessary to ensure proper performance. contact dallas semiconductor at telecom.support@dalsemi.com for recommended oscillators. for referenc e, the telcordia gr-1244-core stability requirements for stratum 3e and stratum 3 are listed in table 7-1 . table 7-1. gr-1244 stratum 3e /3 stability requirements parameter stratum 3e stratum 3 initial offset 1 x 10 -9 50 x 10 -9 temperature 10 x 10 -9 280 x 10 -9 drift (non-temp) 1.16 x 10 -14 /sec ( 1 x 10 -9 /day) 4.63 x 10 -13 /sec ( 40 x 10 -9 /day) note: refer to gr-1244-core for additional details. the stability of the local oscillator is very important, but its absolute frequency accuracy is less important because the DS3101 can compensate for frequency inaccuracies when synthesizing the 204.8mhz master clock from the local oscillator clock. the mc lkfreq field in registers mclk1 and mclk2 specifies the frequency adjustment to be applied. the adjust can be from -771ppm to +514ppm in 0.0196229ppm (i.e., ~0.02ppm) steps.
DS3101 stratum 3/3e timing card ic 20 of 149 the DS3101 implements a stand-alone watc hdog circuit that causes an interrupt on the intreq pin when the local oscillator attached to the refclk pin is significantly off frequ ency. the watchdog interru pt is not maskable, but is subject to the intcr register settings. when the watchdog circuit ac tivates, reads of any and all registers in the device will return 00h to indicate the failure. in response to the activation of the intreq pin or during periodic polling, if system software ever reads 00h from the id registers (which are hard-coded to 0c1dh = 3101 decimal) then it can conclude that the local oscillator attached to that DS3101 has failed. for proper operation of the watchdog timer, connect the wdt pin to a resistor (r) to v ddio and a capacitor (c) to ground. suggested values are r = 20k and c = 0.01 f. 7.4 input clock configuration the DS3101 has 14 input clocks: ic1 to ic14. table 7-2 provides summary information about each clock, including signal format and available frequencies. the device tolerates a wide range of duty cycles on input clocks, out to a minimum high time or minimum low time of 3ns or 30% of the clock period, whichever is smaller. 7.4.1 signal format configuration inputs with cmos/ttl signal format ac cept both ttl and 3.3v cmos levels. one key configuration bit that affects the available frequencies is the sonsdh bit in mcr3 . when sonsdh = 1 (sonet mode), the 1.544mhz frequency is available. when sonsdh = 0 (sdh mode), the 2.048mhz frequency is available. during reset, the default value of this bit is latched from the sonsdh pin. input clocks ic5 and ic6 can be configured to accept lvds, lvpecl, or cmos/ttl si gnals by using the proper set of external components. the recommended lvds termination is shown in figure 10-1 , and the lvds electrical specifications are listed in table 10-4 . the recommended lvpecl te rmination is shown in figure 10-2 , and the lvpecl electrical specifications are listed in table 10-5 . to configure these differential inputs to accept single- ended cmos/ttl signals, use a voltage-divider to bias the icxneg pin to approxim ately 1.4v and connect the single-ended signal to the icxpos pin. if ic5 or ic6 is not used it should be configured for lvds and left floating (one input is internally pulled high and the other internally pulled low). (see also mcr5 :ic5sf and ic6sf.) by default, input clocks ic1 and ic2 are 64khz composite clock receivers (see section 7.10 ). the composite clock signal is a 64khz ami clock with an embedded 8khz clock i ndicated by deliberate bipolar violations (bpvs) every 8 clock cycles. the 8khz component is the clock that is fo rwarded to the dplls. the ami composite clock electrical specifications are shown in table 10-6 , and the recommended external components are shown in figure 10-3 . ic1 and ic2 can be configured as standard cmos/ttl inputs (identical to ic3) by setting mcr5 :ic1sf = 1 or mcr5 :ic2sf = 1, respectively.
DS3101 stratum 3/3e timing card ic 21 of 149 table 7-2. input clock capabilities input clock signal formats frequencies default frequency ic1 ami or cmos/ttl (3) 64khz composite clock or up to 125mhz 8khz ic2 ami or cmos/ttl (3) 64khz composite clock or up to 125mhz 8khz ic3 cmos/ttl up to 125mhz (1) 8khz ic4 cmos/ttl up to 125mhz 8khz ic5 lvds/lvpecl or cmos/ttl up to 155.52mhz (2) 19.44mhz ic6 lvds/lvpecl or cmos/ttl up to 155.52mhz 19.44mhz ic7 cmos/ttl up to 125mhz 19.44mhz ic8 cmos/ttl up to 125mhz 19.44mhz ic9 cmos/ttl up to 125mhz 19.44mhz ic10 cmos/ttl up to 125mhz 19.44mhz ic11 cmos/ttl up to 125mhz master mode (mastslv = 1): 19.44mhz slave mode (mastslv = 0): 6.48mhz ic12 cmos/ttl up to 125mhz sonet mode (sonsdh = 1): 1.544mhz sdh mode (sonsdh = 0): 2.048mhz ic13 cmos/ttl up to 125mhz sonet mode (sonsdh = 1): 1.544mhz sdh mode (sonsdh = 0): 2.048mhz ic14 cmos/ttl up to 125mhz sonet mode (sonsdh = 1): 1.544mhz sdh mode (sonsdh = 0): 2.048mhz note 1: available frequencies for cmos/ttl input clocks are 2khz, 4khz, 8khz, 1.544mhz (sonet mode), 2.048mhz (sdh mode), 6.312mhz, 6.48mhz, 19.44mhz, 25.92mhz, 38.88mh z, 51.84mhz, 77.76mhz, and n x 8khz for 2 n 15,625. note 2: available frequencies for lvds/lvpecl input clocks include a ll cmos/ttl frequencies in note 1 plus 155.52mhz. note 3: signal formats for ic1 and ic2 are controlled by mcr5 :ic1sf and ic2sf, respectively.
DS3101 stratum 3/3e timing card ic 22 of 149 7.4.2 frequency configuration input clock frequencies are configured in the freq field of the icr registers. the divn a nd lock8k bits of these same registers specify the locking frequency mode, as shown in table 7-3 . table 7-3. locking frequency modes divn lock8k locking frequency mode 0 0 direct lock mode 0 1 lock8k mode 1 x divn mode 7.4.2.1 direct lock mode in direct lock mode, the dplls lock to the selected re ference at the frequency specified in the corresponding icr register. direct lock mode can only be used for input cl ocks with these specific fr equencies: 2khz, 4khz, 8khz, 1.544mhz, 2.048mhz, 6.312mhz, 6.48mhz, 19.44mh z, 25.92mhz, 38.88mhz, 51.84mhz, 77.76mhz, and 155.52mhz. for the 155.52mhz case, the input clock is inte rnally divided by two, and the dpll direct-locks at 77.76 mhz. the t0 dpll can direct-lock to all the specific inpu t frequencies listed above, and so can the t4 dpll when configured for 77.76mhz operation (see section 7.8.2.2 ). when configured for non -77.76mhz operation, the t4 dpll can direct-lock to any of the spec ific frequencies listed above from 2k hz to 6.48mhz, but for the specific frequencies of 19.44mhz and higher, the input must be configured for lock8k or divn mode. mtie may be somewhat lower in direct lock mode because the higher frequencies allow more frequent phase updates. 7.4.2.2 lock8k mode in lock8k mode, an internal divider is configured to di vide the selected reference down to 8khz. the dplls lock to the 8khz output of the divider. lock8k mode can only be used for input clocks with these frequencies: 8khz, 1.544mhz, 2.048mhz, 6.312mhz, 6.48mhz, 19.44mh z, 25.92mhz, 38.88mhz, 51.84mhz, 77.76mhz, and 155.52mhz. lock8k mode is enabled for a particular input clock by setting the lock8k bit in the corresponding icr register. lock8k mode gives a greater tolerance to input jitter because it uses lower frequencies for phase comparisons. the clock edge to lock to on the selected reference can be configured using the 8kpol bit in the test1 register. for 2khz and 4khz clocks, the lock8k bit is ignored and direct-lock mode is used. 7.4.2.3 divn mode in divn mode, the internal divider is configured from the value stored in the divn registers. the divn value must be chosen so that when the selected reference is divided by divn+1 the output clock is 8khz. the dplls lock to the 8khz output of the divider. divn mode can only be used for input clocks whose frequency is an integer multiple of 8 khz and less than or equal to 155.52mhz. the divn r egister field can range from 1 to 19,439 inclusive. the same divn+1 factor is used for all input clocks configured for divn mode. when divn = 1 in an icr register, the freq field of that register is ignored. note that alt hough divn divider is able to divide down clock rates has as high as 155.52mhz (divn = 19,439), the cmos/ttl input s are only rated for a maximum clock rate of 125mhz (divn = 15,624).
DS3101 stratum 3/3e timing card ic 23 of 149 7.5 input clock quality monitoring each input clock is continuously monitored for frequenc y accuracy and activity. frequency monitoring is described in section 7.5.1 , while activity monitoring is described in sections 7.5.2 and 7.5.3 . any input clock that has a frequency out-of-band alarm or activity alarm is automatically declared invalid. the valid/invalid state of each input clock is reported in the corresponding real-time status bit in register valsr1 or valsr2 . when the valid/invalid state of a clock changes, the corresponding latched status bit is set in register msr1 or msr2 , and an interrupt request occurs if the corresponding inte rrupt enable bit is set in registers ier1 or ier2 . input clocks marked invalid cannot be selected as the reference for either dpll. if the t4 dpll does not have any valid input clocks available, the t4noin status bit is set to 1 in msr3 . 7.5.1 frequency monitoring the DS3101 monitors the frequency of each input clock an d invalidates any clock whose frequency is outside of specified limits. two frequency limits c an be specified: a soft limit and a hard limit. for all input clocks except the t0 dpll?s selected reference, these limits are specified in the ilimit register. for the t0 dpll?s selected reference the limits ar e specified in the srlimit register. when the frequency of an input clock is greater than or equal to the soft limit, the corresponding soft alarm bit is set to 1 in the 5 isr registers. the soft limit is only for monitoring; triggering it does not invalidate the clock. when the frequency of an input clock is greater than or equal to the hard limit, the corresponding hard alarm bit is set to 1 in the 15 isr registers, and the clock is marked invalid in the valsr registers. monitoring according to the hard and soft limits is enabled/disabled using the harden and soften bits in the mcr10 register. both the ilimit and srlimit registers have a default soft limit of 11.43ppm and a default hard limit of 15.24ppm. limits can be set from 3.81ppm to 60.96ppm in 3.81ppm steps. both the soft and hard alarm limits have hyst eresis as required by gr-1244. frequency monitoring is only done on an input clock when the clock does not have an activity alarm. frequency measurement can be done with respect to t he internal 204.8mhz master clock or the 77.76mhz t0 dpll output, as specified by the fmonclk bit in mcr10 . measured frequency can be read from any frequency monitor by specifying the input clock in the fmeasin field of mcr11 and reading the frequency from the fmeas register. 7.5.2 activity monitoring each input clock is monitored for activity and proper behavior using a leaky bucket accumulator. a leaky bucket accumulator is similar to an analog integrator: the out put amplitude increases in the presence of input events and gradually decays in the absence of events. when event s occur infrequently, the accumulator value decays fully between events and no alarm is declared. when events occu r close enough together, the accumulator increments faster than it can decay and eventually reaches the alarm threshold. after an alarm has been declared, if events occur infrequently enough, the accumulator can decay fast er than it is incremented and eventually reaches the alarm clear threshold. the leaky bucket accumulator for each input clock can be as signed one of four configurations (0 through 3) in the bucket field of the icr registers. each leaky bucket configuration has programmable size, alarm declare threshold, alarm clear threshold, and decay rate, all of which are specified in the lbxy registers at addresses 50h through 5fh. activity monitoring is divided into 128ms intervals. the ac cumulator is incremented once for each 128ms interval in which the input clock is inactive for more than two cycles (more than four cycles fo r 155.52mhz input clocks). thus the ?fill? rate of the bucket is at most 1 unit per 128ms, or approximately 8 units /second. during each period of 1, 2, 4 or 8 intervals (programmable), the accumulator decrements if no irregularities occur. th us the ?leak? rate of the bucket is approximately 8, 4, 2, or 1 uni ts/second. a leak is prev ented when a fill event occurs in the same interval. when the value of an accumulator reaches the alarm threshold ( lbxu register), the corresponding act alarm bit is set to 1 in the 115 isr registers, and the clock is marked invalid in the valsr registers. when the value of an accumulator reaches the alarm clear threshold ( lbxl register), the activity alarm is cleared by clearing the clock?s act bit. the accumulator cannot increment past the size of the bucket specified in the lbxs register. the decay rate of the accumulator is specified in the lbxd register. the values stored in the leaky bucket configuration registers must have the following relationship at all times: lbxs lbxu > lbxl .
DS3101 stratum 3/3e timing card ic 24 of 149 when the leaky bucket is empty, the minimum time to decl are an activity alarm in seconds is lbxu / 8 (where the ?x? in ?lbxu? is the leaky bucket configuration number, 0 to 3). the minimum time to clear an activity alarm in seconds is [2 lbxd x (lbxs - lbxl) / 8]. for example, assume lbxu = 8, lbxl = 1, lbxs = 10, and lbxd = 0. the minimum time to declare an activity alarm would be 8 / 8 = 1 second. the minimum time to clear the activity alarm would be [2 0 x (10 - 1) / 8 = 1.125 seconds]. for input clocks ic1 and ic2 configured in composite clock mode, if mcr5 :biterr = 1, then the accumulator is also incremented whenever a violation of the one-bpv-in-eight pattern is detected. 7.5.3 selected reference activity monitoring the input clock that each dpll is cu rrently locked to is called the select ed reference. the quality of a dpll?s selected reference is exceedingly important, since missing cycles and other anomalies on the selected reference can cause unwanted jitter, wander or frequency offset on the output clocks. when anomalies occur on the selected reference they must be detected as soon as possible to give the dpll opportunity to temporarily disconnect from the reference until the reference is available again. by design, the regular input clock activity monitor (section 7.5.2 ) is too slow to be suitable for monitoring the selected reference. instead, each dpll has its own fast activity monitor that detects inactivity within approximately two missing reference clock cycles (within approximately four missing cycles for 155.52mhz references). when the t0 dpll detects a no-activity event, it immediat ely enters mini-holdover mode to isolate itself from the selected reference and sets the srfail bit in msr2 . the setting of the srfail bit can cause an interrupt request on the intreq pin if the corresponding enable bit is set in ier2 . if mcr10 :srfpin = 1, the srfail output pin follows the state of the srfail status bit. optionally, a no- activity event can also cause an ultra-fast reference switch (see section 7.6.4 ). when phlim1 :nalol = 0 (default), the t0 dpll does not declare loss-of-lock during no-activity events. if the selected reference becomes avail able again before any alarms are declared by the activity monitor or frequency monitor, then the t0 dpll continue s to track the selected reference using nearest-edge locking ( 180 ) to avoid cycle slips. when nalol = 1, the t0 dp ll declares loss-of-lock during no-activity events. this causes the t0 state machine to transition to the loss-of-lock state, which sets the msr2 :state bit and causes an interrupt request if enabled. if the selected reference becomes av ailable again before any alarms are declared by the activity monitor or frequency monitor, then the t0 dpll tracks the selected reference using phase/frequency locking ( 360 ) until phase lock is reestablished. when the t4 dpll detects a no-activity event, its behav ior is similar to the t0 dpll with respect to the phlim1 :nalol control bit. unlike the t0 dpll, however, t he t4 dpll does not set the srfail status bit. if nalol = 1, the t4 dpll clears the opstate :t4lock status bit, which sets msr3 :t4lock and causes an interrupt request if enabled. 7.5.4 composite clock inputs when input clocks ic1 and ic2 are co nfigured for composite clock mode ( mcr5 :ic1sf = 0 and mcr5 :ic2sf = 0), they are also monitored for various defe cts (ami error, los, etc.) see section 7.10.1 for further details.
DS3101 stratum 3/3e timing card ic 25 of 149 7.6 input clock priority, selection, and switching 7.6.1 priority configuration during normal operation, the selected reference for t he t0 dpll and the selected reference for the t4 dpll are chosen automatically based on the priori ty rankings assigned to the input cloc ks in the input priority registers ( ipr1 to ipr7 ). each of these seven registers has priority fi elds for two input clocks. when t4t0 = 0 in the mcr11 register, the ipr registers specify the input clock prioriti es for the t0 dpll. when t4t0 = 1, the ipr registers specify the input clock priorities for the t4 dpll. the def ault input clock priorities, for both plls, are shown in table 7-4 . any unused input clock should be given the priority value 0, which disables the clock and marks it as unavailable for selection. priority 1 is highest while priority 15 is lowest. the same priority can be given to two or more clocks. table 7-4. default in put clock priorities input clock default priority input clock default priority ic1 2 ic8 9 ic2 3 ic9 10 ic3 4 ic10 11 ic4 5 ic11 12 or 1 (1) ic5 6 ic12 13 ic6 7 ic13 14 ic7 8 ic14 15 note 1: during reset, the default priority for ic11 is set to 12 in the master device and set to 1 in the slave device. devices are configured as master and slave by the value of the mastslv pin. (the state of the mastslv pin is mirrored in the mastslv bit of the mcr3 register.) see section 7.9 . 7.6.2 automatic selection algorithm the real-time valid/invalid state of eac h input clock is maintained in the valsr1 and valsr2 registers. the selected reference can be marked invalid for phase, frequency or activity. ot her input clocks can be invalidated for frequency or activity. the reference selection algorithm for each dpll chooses t he highest-priority valid input clock to be the selected reference. to select the proper input cl ock based on these criteria, the selection algorithm maintains a priority table of valid inputs. the top three entries in this t able and the selected reference are displayed in the ptab1 and ptab2 registers. when t4t0 = 0 in the mcr11 register, these registers indicate the highest priority input clocks for the t0 dpll. when t4t0 = 1, they indicate t he highest priority input clocks for the t4 path. if two or more input clocks are given the same priority number then those inputs are pr ioritized among themselves using a fixed circular list. if one equal-priority clock is the selected reference but becomes invalid then the next equal-priority clock in the list becomes the selected refere nce. if an equal-priority clock that is not the selected reference becomes invalid, it is simply skipped over in t he circular list. the selection among equal-priority inputs is inherently nonrevertive, and revertive switching mode (s ee next paragraph) has no effect in the case where multiple equal-priority inputs have the highest priority. an important input to the selection algori thm for t0 dpll is the revert bit in the mcr3 register. in revertive mode (revert = 1), if an input clock with a higher priori ty than the selected referenc e becomes valid, the higher- priority reference immediat ely becomes the selected reference. in nonrevertive mode (r evert = 0), the higher- priority reference does not immediately become the sele cted reference but does become the highest-priority reference in the priority table (ref1 field in the ptab1 register). (the selection algorithm always switches to the highest-priority valid input when the se lected reference goes invalid, regard less of the state of the revert bit.) for many applications, nonrevertive mode is preferred fo r the t0 dpll because it minimizes disturbances on the output clocks due to reference switching. the t4 dpll always operates in revertive mode. in nonrevertive mode, planned switchover to a newly va lid higher priority input clock can be done manually under software control. the validation of the new higher pr iority clock sets the corre sponding status bit in the msr1 or
DS3101 stratum 3/3e timing card ic 26 of 149 msr2 register, which can drive an interrupt request on the intreq pin if needed. system software can then respond to this change of state by briefly enabling re vertive mode (toggling revert high then back low) to drive the switchover to the higher priority clock. in most systems redundant timing card s are required, with one functioning as the master and the other as the slave. in such systems the priority t ables of the master and slave must matc h. the DS3101?s register set makes it easy for the slave?s priority table to track the master?s table. at system start-up, the same priorities must be assigned to the input clocks, for both dplls, in the master and slave devic es. during operation, if an input clock becomes valid or invalid in one device (master or slave), the change is flagged in that device?s msr1 or msr2 register, which can drive an interrupt request on the intr eq pin if needed. the real-time valid/invalid state of the input clocks can then be read from that device?s valsr1 and valsr2 registers. once the nature of the state change is understood, the control bits of the other device?s valcr1 and valcr2 registers can be manipulated to mark clocks invalid in the other device as well. 7.6.3 forced selection the t0force field in the mcr2 register and the t4force field in the mcr4 register provide a way to force a specified input clock to be the selected reference for the t0 and t4 dplls, respectively. in both t0force and t4force, values of 0 and 15 specify normal operation with automatic reference selection. values from 1 to 14 specify the input clock to be the forced selection. interna lly forcing is accomplished by giving the specified clock the highest priority (as specified in ptab1 :ref1). in revertive mode ( mcr3 :revert = 1) the forced clock automatically becomes the selected reference (as specified in ptab1 :selref) as well. in nonrevertive mode (t0 dpll only) the forced clock only be comes the selected reference when the existing selected reference is invalidated or made unavailable for select ion. in both revertive and nonrevertive modes when an input is forced to be the highest priority, the normal highest priority input (when no input is forced) is listed as the second-highest priority ( ptab2 :ref2) and the normal second-highest priority input is listed as the third-highest priority ( ptab2 :ref3). 7.6.4 ultra-fast reference switching by default, disqualification of the select ed reference and switchover to another reference occurs when the activity monitor?s inactivity alarm threshold has been crossed, a process that takes on the order of hundreds of milliseconds or seconds. for the t0 dpll, an option for extremely fast disqualificat ion and switchover is also available. when ultra-fast switching is enabled ( mcr10 :ufsw = 1), if the fast activity monitor detects approximately two missing clock cycles it declares the refe rence failed by forcing the leaky bucket accumulator to its upper threshold (see section 7.5.2 ) and initiates reference switching. this is in addition to setting the srfail bit in msr2 and optionally generating an interrupt request, as described in section 7.5.3 . when ultra-fast switching occurs, the t0 dpll transitions to the prelocked 2 state, which allows switching to occur faster by bypassing the loss-of-lock state. the devi ce should be in non-revertive mode when ul tra-fast switching is enabled. if the device is in revertive mode, ultra-fast switching could cause ex cessive reference switching when the highest priority input is intermittent. 7.6.5 external reference switching mode in the external reference switching mode, the srcsw in put pin controls reference switching between two clock inputs. this mode is enabled by setting the extsw bit to 1 in the mcr10 register. in this mode, if the srcsw pin is high, the device is forced to lock to input ic3 (if the pr iority of ic3 is nonzero in ipr2 ) or ic5 (if the priority of ic3 is zero) whether or not the selected input has a valid refe rence signal. if the srcsw pin is low the device is forced to lock to input ic4 (if the pr iority of ic4 is non-zero in ipr2 ) or ic6 (if the priority of ic4 is zero) whether or not the selected input has a valid reference signal. during reset the default value of the extsw bit is latched from the srcsw pin. if external reference switching mode is enabled during reset, the default frequency tolerance ( dlimit registers) is configured to 80ppm rather than the normal default of 9.2ppm. in external reference switching mode the device is simp ly a clock switch, and the dpll is forced to lock onto the selected reference whether it is valid or not. unlike forced reference selection (section 7.6.3 ) this mode controls the ptab1 :selref field directly and is therefor e not affected by the state of the mcr3 :revert bit. during external reference switching mode, only ptab1 :selref is affected; the ref1, ref2 and ref3 fields in the ptab registers continue to indicate the highest, second-highes t, and third-highest priority valid inputs chosen by the automatic selection logic. external refer ence switching mode only affects the t0 dpll.
DS3101 stratum 3/3e timing card ic 27 of 149 7.6.6 output clock phase continuity during reference switching if phase build out is enabled (pboen = 1 in mcr10 ) or the dpll frequency limit ( dlimit ) is set to less than 30ppm then the device always complies with the gr-1244-co re requirement that the rate of phase change must be less than 81ns per 1.326ms during reference switching. 7.7 dpll architecture and configuration both the t0 and t4 paths of the device are digital plls (dplls) with analog plls (aplls) at the output stage. this architecture combines the benefits of both pll types. digital plls have two key benefits: (1) stable, repeatable perform ance that is insensitive to process variations, temperature and voltage, and (2) flexible behavior that is easily programmed vi a configuration registers. dplls use digital frequency synthesis (dfs) to generate various cl ocks. in dfs, a high-speed master clock (204.8mhz) is multiplied up from the 12.800mhz local oscillator clock applie d to the refclk pin. this master clock is then digitally divided down to the desired output frequency. since the resolution of the dfs process is one master clock cycle or 4.88ns, the dfs output clock has jitter of up to 1 master clock ui (4.88ns) pk-pk. the analog plls filter the jitter from the dplls, reduc ing the 4.88ns pk-pk jitter to 0.5ns pk-pk and 60ps rms, typical, measured broadband (10hz to 1ghz). the dplls in the device are configurable for many p ll parameters including bandwidth, damping factor, input frequency, pull-in/hold-in range, loop frequency, output frequency, input-to-output phase offset, phase build-out, and more. no knowledge of loop equations or gain parameters is required to configure and operate the device. no external components are required for the dplls or the apl ls except the high-quality local oscillator connected to the refclk pin. the t0 path is the main path through the device, and th e t0 dpll has a full free-r un/locked/holdover state machine and full programmability. the t4 path is a simpler freq uency converter/ synthesis path, lacking the low bandwidth settings, phase build-out, phase adjustment c ontrols, and holdover state found in the t0 dpll. 7.7.1 t0 dpll state machine the t0 dpll has three main timing modes: locked, holdov er, and free-run. the control state machine for the t0 dpll has states for each timing mode as well as three te mporary states: prelocked, prelocked 2, and loss-of-lock. the state transition diagram is shown in figure 7-1 . descriptions of each state are given in the paragraphs below. during normal operation the state machine controls state transitions. when necessary, however, the state can be forced using the t0state field of the mcr1 register. whenever the t0 dpll changes state, the state bit in msr2 is set, which can cause an interrupt request if enabled. the current t0 dpll state can be read from the t0state field of the opstate register. 7.7.1.1 free-run state free-run mode is the reset default state. in free-run, all output clocks are derived from the 12.800mhz local oscillator attached to the refclk pin. the frequency of each ou tput clock is a specific multiple of the local oscillator. the frequency accuracy of eac h output clock is equal to the frequen cy accuracy of the master clock (see section 7.3 ). the state machine transitions from free-run to t he prelocked state when at least one input clock is valid. 7.7.1.2 prelocked state the prelocked state provides a 100 -second period (default value of phlkto register) for the dpll to lock to the selected reference. if phase lock is achieved during this peri od then the state machine transitions to locked mode. if the dpll fails to lock to the selected reference within the phase-lock time-out period specified by phlkto then a phase lock alarm is raised (corresponding lock bit set in the isr register), invalidating the input (icn bit goes low in valsr registers). if another input clock is valid then the st ate machine re-enters the prelocked state and tries to lock to the alternate input clock. if no other input clocks are valid then the state machine transitions back to the free-run state. in revertive mode (revert = 1 in mcr3 ), if a higher priority input clock becomes valid during the phase-lock timeout period, then the state machine re -enters the prelocked state and tries to lock the higher priority input. if a
DS3101 stratum 3/3e timing card ic 28 of 149 phase-lock timeout period longer than 100 seconds is required for locking (such as 700 seconds for stratum 3e applications), the phlkto register must be configured accordingly. figure 7-1. t0 dpll state transition diagram free-run select ref (001) pre-locked wait for <=100s (110) reset all input clocks evaluated at least one input valid (selected reference invalid or out of lock >100s) and no valid input clock locked (100) phase-locked to selected reference loss-of-lock wait for <=100s (111) holdover select ref (010) loss-of-lock on selected reference phase-lock regained on selected reference within 100s pre-locked 2 wait for <=100s (101) (selected reference invalid or out of lock >100s) and no valid input clock available [selected reference invalid or (revertive mode and valid higher-priority input) or out of lock >100s] and valid input clock available [selected reference invalid or out of lock >100s or (revertive mode and valid higher-priority input)] and valid input clock available [selected reference invalid or out of lock >100s or (revertive mode and valid higher-priority input)] and valid input clock available (selected reference invalid or out of lock >100s) and no valid input clock available all input clocks evaluated at least one input valid selected reference invalid and no valid input clock available [selected reference invalid or (revertive mode and valid higher-priority input)] and valid input clock available phase-locked to selected reference note 1: an input clock is valid when it has no activity alarm, no hard frequency limit alarm, and no phase lock alarm (see the valsr registers and the isr registers). note 2: all input clocks are continuously m onitored for activity and frequency. note 3: only the selected reference is monitored for loss of lock. note 4: phase lock is declared internally when the dpll has maintai ned phase lock continuously for approximately 1 to 2 seconds. note 5: to simply the diagram, the phase-lock timeout period is always shown as 100s, which is the default value of the phlkto register. longer or shorter timeout per iods can be specified as needed by wr iting the appropriate value to the phlkto register.
DS3101 stratum 3/3e timing card ic 29 of 149 7.7.1.3 locked state the t0 dpll state machine can reach the locked state from the prelocked, prelocked 2, or loss-of-lock states when the dpll has locked to the selected reference for at least one second (see section 7.7.6 ). in the locked state, the output clocks track the phase and frequency of the selected reference. while in the locked state, if the selected reference is so impaired that an activity alarm or a hard frequency limit alarm is raised (corresponding act or hard bit set in the isr register), then the selected reference is invalidated (icn bit goes low in valsr registers), and the state machine immediately transitions to either the prelocked 2 state (if another valid input clock is available) or the holdover state (if no other input clock is valid). if loss-of-lock is declared while in the locked state, the state machine transitions to the loss-of-lock state. 7.7.1.4 loss-of-lock state when the loss-of-lock detectors (see section 7.7.6 ) indicate loss-of-phase lock, the state machine immediately transitions from the locked state to the loss-of-lock stat e. in the loss-of-lock state the dpll tries for 100 seconds (default value of phlkto register) to regain phase lock. if phase lock is regained during that period, the state machine transitions back to the locked state. if, during the phase-lock tim eout period specified by phlkto , the selected reference is so impaired that an activity alarm or a hard frequency limit alarm is raised (corresponding act or hard bit set in the isr registers), then the selected reference is invalidated (icn bit goes low in valsr registers), and the state machine immediately transitions to either the prelocked 2 state (if another valid i nput clock is available) or t he holdover state (if no other input clock is valid). if phase lock cannot be regained by the end of the phase-loc k timeout period, then a phase lock alarm is raised (corresponding lock bit set in the isr registers), the selected reference is invalidated (icn bit goes low in valsr registers), and the state machine transiti ons to either the prelocked 2 state (if another valid input clock is available) or the holdover state (if no other input clock is valid). 7.7.1.5 prelocked 2 state the prelocked and prelocked 2 states are similar. the pr elocked 2 state provides a 100-second period (default value of phlkto register) for the dpll to lock to the new selected reference. if phase lock is achieved during this period, then the state machine transitions to locked mode. if the dpll fails to lock to the new selected referenc e within the phase-lock timeout period specified by phlkto , then a phase lock alarm is raised (corresponding lock bit set in the isr registers), invalidating the input (icn bit goes low in valsr registers). if another input clock is valid, the st ate machine re-enters the prelocked 2 state and tries to lock to the alternate input clock. if no other i nput clocks are valid, the state machine transitions to the holdover state. in revertive mode (revert = 1 in mcr3 ), if a higher priority input clock becomes valid during the phase-lock timeout period, the state machine re-ent ers the prelocked 2 state and tries to lock to the higher priority input. if a phase-lock timeout period longer than 100 seconds is required for locking (such as 700 seconds for stratum 3e applications), then the phlkto register must be configured accordingly. 7.7.1.6 holdover state the device reaches the holdover state when it declares its selected reference invalid and has no other valid input clocks available. during holdover the t0 dpll is not phase locked to any input clo ck but instead generates its output frequency from stored frequency in formation, typically the averaged fre quency of the dpll when it was in the locked state. the device can be configured for manual or automatic holdover as described in the following subsections. when at least one input clock has been declar ed valid the state machine immediately transitions from holdover to the prelocked 2 state and tries to lock to the highest priority valid clock. 7.7.1.6.1 automatic holdover for automatic holdover (manho = 0 in mcr3 ), the device can be further confi gured for instantaneous mode or averaged mode. in instantaneous mode (avg = 0 in hocr3 ), the holdover frequency is set to the dpll?s current frequency at the moment of entry into holdover (i.e., the value of the freq field in the freq1 , freq2 and freq3 registers when mcr11 :t4t0 = 0). the freq field is the dpll?s integral path and therefore is an average
DS3101 stratum 3/3e timing card ic 30 of 149 frequency with a rate of change inversely proportional to the dpll bandwidth. the dpll?s proportional path is not used to minimize the effect of recent p hase disturbances on the holdover frequency. in averaged mode (avg = 1 in hocr3 ), the holdover frequency is set to an internally averaged value. during locked operation the frequency indicated in the freq field is internally averaged. the fast bit in hocr3 determines the period of this averaging. when fast = 1 the frequency is averaged for a period of approximately 8 minutes. when fast = 0 (slow), the frequency is aver aged for a period of approximately 110 minutes. the t0 dpll indicates that it has acquired valid holdover val ues by setting the fhordy and shordy status bits in valsr2 (real-time status) and msr4 (latched status). if fast = 0 and th e t0 dpll must enter holdover before the 110-minute average is available, t hen the 8-minute average is used, if available. otherwise the instantaneous value from the integral path is used. if fast = 1 and the t0 dpll must enter holdover before the 8-minute average is available, then the instantaneous value is used. 7.7.1.6.2 manual holdover for manual holdover (manho = 1 in mcr3 ), the holdover frequency is set by the hofreq field in the hocr1 , hocr2 and hocr3 registers. the hofreq field has the same si ze and format as the current frequency field (freq[18:0] in the freq1 , freq2 , and freq3 registers). if desired, software c an, during locked operation, read the current frequency from freq, filter or average it over time, and then writ e the resulting holdover frequency to hofreq. the freq field is derived from the dpll?s integral path, and thus c an be considered an average frequency with a rate of change inversely proportional to the dpll bandwidth. to combine internal averaging with additional software f iltering, the hofreq field can be configured to read out the internally averaged frequency when rdavg = 1 in the hocr3 register. this averaged value can be read from hofreq regardless of the current holdover mode. the fast bit in hocr3 specifies whether the value read is from the fast averager or the slow averager. 7.7.1.7 mini-holdover when the selected reference fails, t he fast activity monitor (section 7.5.3 ) isolates the t0 dpll from the reference within one or two clock cycles to avoid adverse effects on the dpll frequency. when this fast isolation occurs, the dpll enters mini-holdover mode, with a mini-holdover frequency as specified by the miniho field of hocr3 . mini- holdover lasts until the selected reference returns or a ne w input clock has been chosen as the selected reference or the state machine enters the holdover state. note that when the t0 dp ll is configured for manual holdover ( mcr3 :manho = 1), mini-holdover is also configured for manual holdover and hocr3 :miniho is ignored. 7.7.2 t4 dpll state machine the t4 dpll has a simpler state machine than the t0 dpll, as shown in figure 7-2 . the t4 dpll states are similar to the equivalent states of the t0 dpll. note t hat the t4 dpll only operates in revertive switching mode.
DS3101 stratum 3/3e timing card ic 31 of 149 figure 7-2. t4 dpll state transition diagram free-run pre-locked reset all input clocks evaluated at least one input valid locked phase-locked to selected reference loss-of-lock on selected reference selected reference invalid and valid input clock available selected reference invalid and no valid input clock available selected reference invalid and valid input clock available selected reference invalid and no valid input clock available 7.7.3 bandwidth the bandwidth of the t4 dpll is configured in the t4bw register to be 18hz, 35hz, or 70hz. this bandwidth value is used for both acquisition and locked mode. the bandwidth of the t0 dpll is configured in the t0abw and t0lbw registers for various values from 0.5mhz to 70hz. the autobw bit in the mcr9 register controls automatic bandwidth selection. when autobw = 1, the t0 dpll uses the t0abw bandwidth during acquisition ( not phase locked) and the t0lbw bandwidth when phase locked. when autobw = 0 the t0 dpll uses the t0lbw bandwidth all the time, both during acquisition and when phase locked. when limint = 1 in the mcr9 register, the dpll?s integral path is lim ited (i.e., frozen) when the dpll reaches minimum or maximum frequency. setting limint = 1 minimizes overshoot when the dpll is pulling in.
DS3101 stratum 3/3e timing card ic 32 of 149 7.7.4 damping factor the damping factor for the t0 dpll is configured in the damp field of the t0cr2 register, while the damping factor the t4 dpll is configured in the damp field of the t4cr2 register. the reset default damping factors for both dplls are chosen to give a maximum wander gain pe ak of approximately 0.1db. available settings are a function of dpll bandwidth (configured in the t4bw , t0abw , and t0lbw registers). see table 7-5 . table 7-5. damping factors and peak jitter/wander gain bandwidth damp[2:0] value damping factor gain peak (db) 0.5mhz to 4hz 1, 2, 3, 4, 5 5 0.1 1 2.5 0.2 8hz 2, 3, 4, 5 5 0.1 1 1.2 0.4 2 2.5 0.2 18 hz 3, 4, 5 5 0.1 1 1.2 0.4 2 2.5 0.2 3 5 0.1 35 hz 4, 5 10 0.06 1 1.2 0.4 2 2.5 0.2 3 5 0.1 4 10 0.06 70 hz 5 20 0.03 7.7.5 phase detectors phase detectors are used to compare a pll?s feedback cloc k with its input clock. several phase detectors are available in both the t0 and t4 dplls: phase/frequency detector (pfd) early/late phase detector (pd2) for fine resolution multicycle phase detector (mcpd) for large input jitter tolerance these detectors can be used in combination to give fine ph ase resolution combined with large jitter tolerance. as with the rest of the dpll logic, the phase detectors operate at input frequencies up to 77.76mhz. the multicycle phase detector detects and remembers phase differences of many cycles (up to 8191ui). the phase detectors can be configured for normal phase/frequency locking ( 360 capture) or nearest-edge phase locking ( 180 capture). with nearest-edge detection the phase de tectors are immune to occasional missing clock cycles. the dpll automatically switches to nearest-edge locking when the multicycle phase detector is disabled and the other phase detectors determine that phase lock has been achieved. setting d180 = 1 in the test1 register disables nearest-edge locking and forc es the dpll to use phase/frequency locking. the early/late phase detector, also known as phase detecto r 2, is enabled and configured in the pd2* fields of registers t0cr2 and t0cr3 for the t0 dpll and registers t4cr2 and t4cr3 for the t4 dpll. the reset default settings of these registers are appropri ate for all operating modes. adjustment s only affect small signal overshoot and bandwidth. the multicycle phase detector is enabled by setting mcpden = 1 in the phlim2 register. the range of the mcpd?from 1ui up to 8191ui?is configured in the coarselim field of phlim2 . the mcpd tracks phase position over many clock cycles, giving high jitter tolerance. thus the use of the mcpd is an alternative to the use of lock8k mode for jitter tolerance. when usemcpd = 1 in phlim2 , the mcpd is used in the dpll loop, givi ng faster pull-in but more overshoot. in this mode the loop has similar behavior to lock8k mode. in both cases large phase differences contribute to the dynamics of the loop. when enabled by mcpden = 1, the mcpd tracks the phase position whether or not it is used in the dpll loop.
DS3101 stratum 3/3e timing card ic 33 of 149 7.7.6 loss of phase lock detection loss of phase lock is triggered by any of the following in both the t0 and t4 dplls: the fine phase lock detector (measures phase between input an d feedback clocks) the coarse phase lock detector (measures whole cycle slips) hard frequency limit detector inactivity detector the fine phase lock detector is enabled by setting flen = 1 in the phlim1 register. the fine phase limit is configured in the finelim field of phlim1 . the coarse phase lock detector is enabled by setting clen = 1 in the phlim2 register. the coarse phase limit is configured in the coarselim field of phlim2 . this coarse phase lock detector is part of the multicycle phase detector (mcpd) described in section 7.7.5 . the coarselim fields sets both the mcpd range and the coarse phase limit, since the two are equivalent. if loss of phase lo ck should not be declared for multiple-ui input jitter then the fine phase lock detector should be disabled and the coarse phase lock detector should be used instead. the hard frequency limit detector is enabled by setting fllol = 1 in the dlimit3 register. the hard limit for the t0 dpll is configured in registers dlimit1 and dlimit2 . the t4 dpll hard limit is fixed at 80ppm. when the dpll frequency reaches the hard limit, loss-of-lock is declared. the dlimit3 register also has the softlim field to specify a soft frequency limit. exceeding the soft frequency lim it does not cause loss-of-lock to be declared. when the t0 dpll frequency exceeds the soft limit the t0soft status bit is set in the opstate register. when the t4 dpll frequency exceeds the soft limit the t4soft status bit is set in opstate . both the soft and hard alarm limits have hysteresis as required by gr-1244. the inactivity detector is enabled by setting nalol = 1 in the phlim1 register. when this detector is enabled the dpll declares loss-of-lock after one or two missing clock cycles on the select ed reference. see section 7.5.3 . when the t0 dpll declares loss of phase lock, the state ma chine immediately transitions to the loss-of-lock state, which sets the state bit in the msr2 register and requests an interrupt if enabled. when the t4 dpll declares loss of phase lock, the t4lock bit is cleared in the opstate register, which sets the t4lock bit in the msr3 register and requests an interrupt if enabled.
DS3101 stratum 3/3e timing card ic 34 of 149 7.7.7 phase monitor and phase build-out 7.7.7.1 phase monitor the t0 dpll has a phase monitor that measures the pha se error between the input clock reference and the dpll output. the phase monitor is enabled by setting phmon :pmen = 1. when the t0 dpll is set for low bandwidth, a phase transient on the input causes an immediate phase error that is gradually r educed as the dpll tracks the input. when the measured phase error exceeds the limit set in the phmon :pmlim field, the phase monitor declares a phase monitor alarm by setting the msr3 :phmon bit. the pmlim field can be configured for a limit ranging from about 1 s to about 3.5 s. 7.7.7.2 phase build-out in response to input phase transients see telcordia gr-1244-core section 5.7 for an explanation of phase build- out (pbo) and the requirement for stratum 3e clocks to perform pbo in response to input phase transients. when the phase monitor is enabled (as described in section 7.7.7.1 ) and phmon :pmpben = 1, the t0 dpll automatically triggers pbo events in response to input transients greater than the limit set in phmon :pmlim. the range of limits available in the pmlim field allows the t0 dpll to be configured to build out input transients greater than 3.5 s, greater than 1 s, or any threshold in between. to determine when to perform pbo, the phase monitor watches for phase changes greater than 100ns in a 10ms interval on the selected reference. when such a phase ch ange occurs, an internal 0.1 second timer is started. if during this interval the phase change is greater than t he pmlim threshold then a pbo event occurs. during a pbo event the device enters a temporary hol dover state in which the phase difference between the selected reference and the output is measured and fed into the dpll loop to absorb the input transient. after a pbo event, regardless of the input phase transient, the output phase transient is le ss than or equal to 5ns. phase build-out can be frozen at the current phase offset by setting mcr10 :pbofrz = 1. when pbo is frozen the t0 dpll ignores subsequent phase build-out events and maintains the current phase offset between input and outputs. 7.7.7.3 phase build-out in response to reference switching when mcr10 :pboen = 0, phase build-out is not performed dur ing reference switching, and the t0 dpll always locks to the selected reference at zero degrees of phase. with pbo disabled, transitions from a failed reference to the next highest priority reference and transitions from holdover or free-run to locked mode cause phase transients on output clocks as the t0 dpll jumps from its previous phase to the phase of the new selected reference. when mcr10 :pboen = 1, phase build-out is performed during reference switching. with pbo enabled, if the selected reference fails and another valid reference is av ailable then the device enters a temporary holdover state in which the phase difference between the new reference and the output is measured and fed into the dpll loop to absorb the input phase difference. similarly, during transit ions from holdover or free-run to locked mode, the phase difference between the new reference and the output is measured and fed into the dpll loop to absorb the input phase difference. after a pbo event, regardless of the inpu t phase difference, the output phase transient is less than or equal to 5ns. any time that pbo is enabled it can also be frozen at the current phase offset by setting mcr10 :pbofrz = 1. when pbo is frozen the t0 dpll ignores subsequent phase build-out events and maintains the current phase offset between inputs and outputs. disabling pbo while the t0 dpll is in the locked state causes a phase change on the output clocks while the dpll switches to tracking the selected reference with 0 deg rees of phase error. the rate of phase change on the output clocks depends on the dpll bandwi dth. enabling pbo in the locked state also causes a pbo event.
DS3101 stratum 3/3e timing card ic 35 of 149 7.7.7.4 manual phase build-out control software can have manual control over phase build-out, if required. initial configuration for manual pbo involves locking to an input clock with frequency 6.48mhz, setting mcr10 :pboen = 0 and phmon :pmpben = 0 to disable automatic phase build-out, and setting phmon :pmen = 1 and the proper phase limit in phmon :pmlim to enable monitoring for a phase transient. during operation, software can monitor for either a phase transient ( msr3 :phmon = 1) or a t0 dpll state change ( msr2 :state = 1). when either event occurs, software can perform the following procedure to execute a manual phase build-out (pbo) event: 1) read the phase offset from the phase registers to decide whether or not to initiate a pbo event. 2) if a pbo event is desired then save the phase offset and set mcr10 :pboen to cause a pbo event. 3) when the pbo event is complete (wait for a timeout and/or phase = 0), write the manual phase offset registers ( offset ) with the phase offset read earlier. ( note: the phase register is in degrees, the offset register is in picoseconds) 4) clear mcr10 :pboen and wait for the next event that may need a manual pbo. 7.7.7.5 pbo phase offset an uncertainty of up to 5ns is introduced each time a pha se build-out event occurs. this uncertainty results in a phase hit on the output. over a large number of phas e build-out events the mean error should be zero. the pboff register specifies a small fixed offset for each phase bu ild-out event to skew the average error toward zero and eliminate accumulation of phase shifts in one direction. 7.7.8 input to output phase adjustment when phase build-out is disabled (pboen = 0 in mcr10 and pmpben = 0 in phmon ), the offset registers can be used to adjust the phase of the t0 dpll output clocks with respect to the selected reference. output phase offset can be adjusted over a 200ns range in 6ps increments. this phase adjustment occurs in the feedback clock so that the output clocks are adjusted to compensate. the rate of change is t herefore a function of dpll bandwidth. to quickly track large changes in phase, either lock8k mode (section 7.4.2.2 ) or the coarse phase detector (section 7.7.5 ) should be used. simply writing to the offset registers with phase build-out disabled causes a change in the input to output phase which can be considered to be a delay adjustment. 7.7.9 phase recalibration when a phase build-out occurs, either automatic or m anual, the feedback frequency synthesizer does not get an internal alignment signal to keep it aligned with the output dividers, and therefore the phase difference between input and output may become incorrect. this could occur if t here is a power supply glitch or emi event that affects the sequential logic state machines. setting the fscr3 :recal bit periodically causes a recalibration process to be executed, which corrects any phase error that may have occurred. during the recalibration process the device puts the dpll into mini holdover, internally ramps the phase offset to zero, resets all clock dividers, ramps the phase offset to the value stored in the offset registers, and then switches the dpll out of mini holdover. if the offset registers are written during the recalibration process, the process will ramp the phase offset to the new offset value. 7.7.10 frequency and phase measurement standard input clock frequency monitoring is described in section 7.5.1 . the input clock monitors report measured frequency with 3.8ppm resolution. more accurate m easurement of frequency and phase can be accomplished using the dplls. the t0 dpll is always monitoring its se lected reference, but if the t4 dpll is not otherwise used then it can be configured as a high-resolution frequency and phase monitor. software can then connect the t4 dpll to various input clocks on a rotati ng basis to measure frequency and phase. see mcr4 :t4force. dpll frequency measurements can be read from the freq field spanning registers freq1 , freq2 and freq3 . this field indicates the frequency of the selected refere nce for either the t0 dpll or the t4 dpll, depending on the setting of the t4t0 bit in mcr11 . this frequency measurement has a resolution of 0.0003068ppm over a 80ppm range. the value read from the freq field is the dpll?s integral path value, which is an averaged measurement with an averaging time inversely proportional to dpll bandwidth. dpll phase measurem ents can be read from the phase field spanning registers phase1 and phase2 . this field indicates the phase difference seen by the phase det ector for either the t0 dpll or the t4 dpll, depending
DS3101 stratum 3/3e timing card ic 36 of 149 on the setting of the t4t0 bit in mcr11 . this phase measurement has a re solution of approximately 0.7 degrees and is internally averaged with a -3db attenuation poin t of approximately 100hz. thus, for low dpll bandwidths the phase field gives input phase wander in the frequenc y band from the dpll corner frequency up to 100hz. this information could be used by software to compute a crude mtie measurement up to an observation time of approximately 1000 seconds. for the t0 dpll, the phase field always indicates t he phase difference between t he selected reference and the internal feedback clock. the t4 dpll, however, can be configured to measure the phase difference between two input clocks. when t0cr1 :t4mt0 = 1, the t4 path is disabled and t he t4 phase detector is configured to compare the t0 dpll selected reference with the t4 dpll selected reference. any input clock can then be forced to be the t4 dpll selected reference using the t4force field of mcr4 . this feature can be used, for example, to measure the phase difference between the t0 dpll?s selected refe rence and its next highest priority reference. software could compute mtie and tdev with respect to the selected reference for any or all of the other input clocks. when comparing the phase of the t0 and t4 selected references by setting t0cr1 :t4mt0 = 1, several details must be kept in mind. in this mode, the t4 path receives a copy of the t0 selected refe rence, either directly or through a divider to 8khz. if the t4 selected reference is divided down to 8khz using lock8k or divn modes (see section 7.4.2 ), then the copy of the t0 selected reference is also divided down to 8khz. if the t4 selected reference is configured for direct-lock mode, then the copy of the t0 selected reference is not divided down and must be the same frequency as the t4 selected reference. see table 7-6 for more details. (while t0cr1 :t4mt0 = 1 the t0 path continues to lock to the t0 selected reference in the manner specified in the corresponding icr register.) table 7-6. t0 adaptation for t4 phase measurement mode locking mode for t4 selected reference locking mode for t0 selected reference locking mode for copy of t0 selected ref frequency of the t4 selected ref for t4/t0 phase measurement frequency of the t0 selected ref for t4/t0 phase measurement divn or lock8k direct lock8k 8khz 8khz divn or lock8k lock8k lock8k 8khz 8khz divn or lock8k divn divn 8khz 8khz direct any direct same as the t4 selected ref input frequency same as the t0 selected ref input frequency (1) note 1: in this case, the t0 select reference must be the same frequency as the t4 selected reference. note 2: if the t4 selected reference frequency is 8khz and the t0 select ed reference is a different frequency, the two references can b e compared by configuring the t4 selected reference for 8 khz and lock8k mode. this forces the copy of the t0 selected reference to be divided down to 8khz us ing either lock8k or divn mode. 7.7.11 input wander and jitter tolerance the device is compliant with the jitter and wander tolerance requirements of the standards listed in table 1-1 . wander is tolerated up to the point where wander causes an apparent long-term frequency offset larger than the limits specified in the ilimit and/or srlimit registers. in such a situation t he input clock would be declared invalid. jitter is tolerated up to the point of eye closure. either lock8k mode (see section 7.4.2.2 ) or the multicycle phase detector (see section 7.7.5 ) should be used for high jitter tolerance. 7.7.12 jitter and wander transfer in the DS3101, the transfer of jitter and wander from the selected reference to the output clocks has a programmable transfer function that is deter mined by the dpll bandwidth. (see section 7.7.3 .) in the t0 dpll, the 3db corner frequency of the jitter transfer function c an be set to any of 18 positions from 0.5mhz to 70hz. in the t4 dpll, the 3db corner frequency of the jitter tr ansfer function can be set to 18hz, 35hz, or 70hz. during locked mode, the transfer of wander from the loca l oscillator clock (connected to the refclk pin) to the output clocks is not significant as long as the dpll ban dwidth is set high enough to allow the dpll to quickly compensate for oscillator fr equency changes. during free-run and hol dover modes, local osc illator wander has a much more significant effect. see section 7.3 .
DS3101 stratum 3/3e timing card ic 37 of 149 7.7.13 output jitter and wander several factors contribute to jitter and wander on the output clocks, including: jitter and wander amplitude on the selected re ference (while in the locked state) the jitter/wander transfer c haracteristic of the device (while in the locked state) the jitter and wander on the local oscillator clock signal (especially wander while in the holdover state) the dpll in the device has progr ammable bandwidth (see section 7.7.3 ). with respect to jitter and wander, the dpll behaves as a low-pass f ilter with a programmable pole. the bandwidth of the dpll is normally set low enough to strongly attenuate jitter. the wander a ttenuation depends on the dpll bandwidth chosen. over time frequency changes in the local oscillator can cause a phase difference between the selected reference and the output clocks. this is especially true at dpll bandwidths of 0.1hz and below because the dpll?s rate of change may be slower than the oscillator?s rate of change. oscillators with better stability will minimize this effect. in some applications an ocxo may be required rather than a tcxo. in the most demand applications, the ocxo may need to be shielded to further reduce the rate of te mperature change and thus t he rate of frequency change. typical mtie and tdev measurements for t he DS3101 in locked mode are shown in figure 7-3 and figure 7-4 , respectively. figure 7-3. typical mtie for t0 dpll output 0.1 1 10 100 1000 0.01 0.1 1 10 100 1000 10000 observation interval (s) mtie (ns) g.813 option 1 constant temperature mask measured mtie, 19.44 mhz input and output, 4 hz bandwidth , ds4026 tcxo
DS3101 stratum 3/3e timing card ic 38 of 149 figure 7-4. typical tdev for t0 dpll output 0.001 0.01 0.1 1 10 0.01 0.1 1 10 100 1000 10000 observation internval (s) tdev (ns) 7.8 output clock configuration a total of 11 output clock pins, oc1 to oc11, are ava ilable on the device. output clocks oc1 to oc7 are individually configurable for a variety of frequencies derived from either the t0 dpll path or the t4 dpll path. output clocks oc8 to oc11 are more specialized, serving as a dedicated composite clock transmitter (oc8), a 1544/2.048khz clock (oc9), an 8khz frame sync (oc10), and a 2khz multiframe sync (oc11). table 7-7 provides more detail on the capabilities of the output clocks. table 7-7. output clock capabilities output clock signal format frequencies supported oc1 cmos/ttl oc2 cmos/ttl oc3 cmos/ttl oc4 cmos/ttl oc5 cmos/ttl oc6 lvds oc7 lvds frequency selection per section 7.8.2.3 and table 7-9 through table 7-12 oc8 ami 64khz composite clock oc9 cmos/ttl 1.544mhz or 2.048mhz oc10 cmos/ttl 8khz frame sync with programmable pulse width and polarity oc11 cmos/ttl 2khz multiframe sync with programmable pulse width and polarity g.813 option 1 constant temperature mask measured tdev, 19.44 mhz input and output, 4 hz bandwidth , ds4026 tcxo
DS3101 stratum 3/3e timing card ic 39 of 149 7.8.1 signal format configuration output clocks oc6 and oc7 are enabled and disabled via the oc6sf and oc7sf configuration bits in the mcr8 register. the lvds electrical specifications are listed in table 10-4 , and the recommended lvds termination is shown in figure 10-1 . these outputs can be easily interfaced to lvpecl and cml inputs on neighboring ics using a few external passive components. refer to maxim app note hfan-1.0: introduction to lvds, pecl, and cml for details. output clock oc8 is a dedicated composite clock (cc) tr ansmitter. the composite clock signal is a 64khz ami clock with an embedded 8khz clock indi cated by deliberate bipolar violatio ns (bpvs) every 8 clock cycles. see section 7.10.2 for oc8 configuration details. the ami cc electrical specifications are shown in table 10-6 , and the recommended external components are shown in figure 10-3 . output clocks oc1 to oc5 and oc9 to oc11 are always cmos/ttl signal format. 7.8.2 frequency configuration the frequency of most of the output clocks is a function of the settings used to confi gure the components of the t0 and t4 pll paths. these components are shown in the detailed block diagram of figure 7-5 . the t0 and t4 plls use digital frequency synthesis (dfs) to generate various clocks. in dfs, a high-speed master clock (204.8mhz) is divided down to the desired out put frequency. the edges of the output clock, however, are not ideally located in time but rather are aligned with the edges of the master clock resulting in jitter with an amplitude equal to 1 period of the master clock (i.e., 4.88ns). 7.8.2.1 t0 dpll and apll details the 77m forward dfs block (see figure 7-5 ) uses the 204.8mhz master clock and dfs to synthesize a 77.76mhz clock with 4.88ns inherent peak-to-peak jitter. this clock c an be fed directly to the feedback dfs block or it can be passed through the feedback apll to reduce jitter to less than 1ns. the 77m forward dfs block handles phase build-out and any phase offset configured in the offset registers. thus, the 77m output dfs block and the 77m forward dfs block are frequency locked but may have a phase offset. the feedback dfs block takes as its i nput clock either the output from the 77m forward dfs or the jitter-filtered output from the t0 feedback apll. the feedback dfs bloc k synthesizes the appropriate locking frequency for use in the phase-frequency detector (pfd). the 77m output dfs block also uses the 204.8mhz master clock and dfs to synthesize a 77.76mhz clock with 4.88ns peak-to-peak jitter. this clock goes to both the output apll and the low frequency (lf) output dfs block.
DS3101 stratum 3/3e timing card ic 40 of 149 figure 7-5. dpll block diagram locking frequency t0 pfd and loop filter t0 77m foward dfs t0 feedback apll t0 feedback dfs t0 77m output dfs t0 lf output dfs t0 output apll t0 output dividers t0 selected reference oc1 to oc7 oc8, oc9 t4 output dividers t4 output apll t4 foward dfs t4 feedback dfs t4 pfd and loop filter t0 selected reference locking frequency t4 selected reference 8 khz oc10, oc11 t4 path t0 path t4 lf output dfs t0cr1:t0freq[2:0]=000 t0cr1:t0freq[2:0] t0cr1:t0freq[2:0] ocrm:ofreqn[3:0] mcr4:oc89 t0cr1:t4apt0 t0cr1:t4mt0 t4cr1:t4freq[3:0] mcr4:t4dfb mcr4:lkt4t0 mcr4:t4dfb fscr1:2k8ksrc 1 0 1 0 1 0 1 0 1 0 0 1 0 1 the lf output dfs block takes as its input clock either the output from the 77m output dfs or the jitter-filtered output of the output apll. the lf output dfs block synthe sizes three frequencies: digi tal1, digital2, and a third frequency for producing multiple n x ds1/e1 rates vi a the output aplls. when the output apll uses the output from the lf output dfs, the lf output dfs uses the output from the 77m output dfs block to avoid a loop. the lf output dfs also synthesizes frequencies for use by output clocks oc8, oc9, oc10, and oc11. the frequency of the digital1 clock is configured by the dig1ss bit in mcr6 and the dig1f[1:0] field in mcr7 . the frequency of the digital2 clock is configured by the dig2af and dig2ss bits in mcr6 and the dig2f[1:0] field in mcr7 . digital1 and digital2 can be independently conf igured for any of the frequencies shown in table 7-8 . because they are generated by dfs and cannot be filtered by an apll, digital1 and digital2 have relatively high- amplitude jitter. the minimum jitter is approximately 12ns (one period of the input clock to the lf output dfs) when the t0 path is in analog feedback mode. the maximum jitter is approximately 17ns when t0 is in digital feedback mode. both the digital1 and digital2 rates are available to output clocks oc1 to oc7. the output apll takes as its input clock either the output of the 77m output dfs or one of the frequencies from the lf output dfs (77.76mhz, 16 x ds1, 24 x ds1, 12 x e1, or 16 x e1). the output frequency of the output apll is four times the input frequency (e.g., 311.04mhz for 77.76mhz input). the output clock is then divided by 1, 2, 4, 6, 8, 12, 16, and 48. these clock rates are av ailable to the oc1 to oc7 output clocks.
DS3101 stratum 3/3e timing card ic 41 of 149 table 7-8. digital1 an d digital2 frequencies digxf[1:0] setting in mcr7 digxss setting in mcr6 frequency (mhz) 00 0 2.048 01 0 4.096 10 0 8.192 11 0 16.384 00 1 1.544 01 1 3.088 10 1 6.176 11 1 12.352 note: when mcr6 :dig2af = 1, digital2 generates 6312khz (must set mcr6 :dig2ss = 0 and mcr7 :dig2f = 00). 7.8.2.2 t4 dpll and apll details the t4 path is simpler than the t0 path and does not support phase build-out or phase offset. the t4 path can be locked to an input clock or to the t0 path (by setting lkt4t0 = 1 in mcr4 ). using the 204.8mhz master clock and dfs, the t4 forward dfs block generate s a clock with 4.88 ns inherent peak-t o-peak jitter at any of the following frequencies: 16 x ds1, 24 x ds1, 12 x e1, 16 x e1, ds3, 2 x e3, 62.5mhz, or 77.76mhz. this clock can be fed directly to the t4 feedback dfs block (t4dfb = 1 in mcr4 ), or it can be passed through the t4 output apll to reduce jitter to less than 1ns (t4dfb = 0). the t4 feedback dfs block takes as its input clock either the output from the t4 forward dfs or the jitter-filtered output from the t4 output apll, depending on the setting of mcr4 :t4dfb. the t4 feedback dfs block synthesizes the appropriate locking frequency for use in the t4 phase-frequency detector (pfd). the t4 output apll filters jitter to less than 1 ns and takes as its input clock either t he output of the t4 forward dfs block or one of the frequencies fr om the t0 lf output dfs (16xds1, 24xds1, 12xe1, 16xe1 or 4x6312khz, as specified by t0cr1 :t0ft4[2:0]). the output frequency of the out put apll is four times the input frequency (e.g., 311.04mhz for 77.76mhz input). the output clock is then divided by 2, 4, 8, 16, 48, and 64. these clock rates are available to the oc1 to oc7 output clocks. the t4 lf output dfs block normally takes as its input cl ock the jitter-filtered output of the t4 output apll. when the t4 output apll is connected to the t0 lf output dfs ( t0cr1 :t4apt0 = 1), the t4 output apll must be disconnected from the t4 dpll loop by c onfiguring the loop for digital feedback ( mcr4 :t4dfb = 1). in this situation the t4 lf output dfs takes its input from t he t4 forward dfs block. the t4 lf output dfs block generates 2khz and 8khz frequencies for use by output clocks oc1 to oc7 (when fscr1 :2k8ksrc = 1) and synthesizes frequencies for use by output clocks oc8 and oc9 (when mcr4 :oc89 = 1).
DS3101 stratum 3/3e timing card ic 42 of 149 7.8.2.3 oc1 to oc7 configuration the following is a step-by-step procedure for configur ing the frequencies of output clocks oc1 to oc7: 1) determine whether the t4 path must be independ ent of the t0 path or not. if the t4 path must be independent, set t4apt0 = 0 in register t0cr1 . if the t4 path can be locked to the t0 path then set t4apt0 = 1. 2) use table 7-9 to select a set of output frequencies for each path, t0 and t4. each path can only generate one set of output frequencies. (in so net/sdh equipment the t0 path is typically configured for an apll frequency of 311.04mhz in order to get 19.44mhz and/or 38.88mhz output clocks to distribute to system line cards.) 3) determine from table 7-9 the t0 and t4 apll frequencies required for the frequency sets chosen in step 2. 4) configure the t0freq field in register t0cr1 as shown in table 7-10 for the t0 apll frequency determined in step 3. configure the t4freq field in register t4cr1 as shown in table 7-11 for the t4 apll frequency determined in step 3. if the t4 apll is locked to the t0 dpll then the t0ft4 field in t0cr1 must also be configured as shown in table 7-11 . 5) using table 7-9 and table 7-12 , configure the frequencies of output clocks oc1 through oc7 in the ofreqn fields of registers ocr1 to ocr4 . 6) if any of oc1 to oc7 are configured for 2khz or 8khz frequency, set 2k8ksrc = 0 in fscr1 to source these frequencies from the t0 path or 2k 8ksrc = 1 to source these frequencies from the t4 path. table 7-13 lists all possible frequencies for output clocks oc1 to oc7 and specifies how to configure the t0 path and/or the t4 path to obtain each frequency. table 7-13 also indicates the expected jitter amplitude for each frequency. table 7-9. apll frequency to ou tput frequencies (t0 and t4) apll frequency apll/2 apll/4 apll/6 apll/8 apll/12 apll/16 apll/48 apll/64 311.04 155.52 77.76 51.84 38.88 25.92 19.44 6.48 4.86 274.944 137.472 68.376 ? 34.368 ? 17.184 5.728 4.296 250.000 125.000 62.500 ? 31.250 ? 15.625 5.2083 3.90625 178.944 89.472 44.736 ? 22.368 ? 11.184 3.728 2.796 148.224 74.112 37.056 24.704 18.528 12.352 9.264 3.088 2.316 131.072 65.536 32.768 21.84533 16.384 10.92267 8.192 2.73067 2.048 100.992 50.496 25.248 16.832 12.624 8.416 6.312 2.104 1.578 98.816 49.408 24.704 16.46933 12.352 8.23467 6.176 2.05867 1.544 98.304 49.152 24.576 16.384 12.288 8.192 6.144 2.048 1.536 note: all frequencies in mhz. common telecom frequencies are in bold type. table 7-10. t0 apll frequency to t0 path configuration t0 apll frequency (mhz) t0 frequency mode t0freq[2:0] setting in t0cr1 output jitter (pk-pk, ns) 311.04 77.76mhz, digital feedback 000 < 0.5 311.04 77.7mhz, analog feedback 001 < 0.5 98.304 12 x e1 (digital feedback) 010 < 2 131.072 16 x e1 (digital feedback) 011 < 2 148.224 24 x ds1 (digital feedback) 100 < 2 98.816 16 x ds1 (digital feedback) 101 < 2 100.992 4 x 6312khz (digital feedback) 110 < 2
DS3101 stratum 3/3e timing card ic 43 of 149 table 7-11. t4 apll frequency to t4 path configuration t4 apll frequency (mhz) t4 frequency mode t4 forward dfs freq (mhz) t4apt0 setting in t0cr1 t4freq[3:0] setting in t4cr1 t0ft4[2:0] setting in t0cr1 output jitter (pk-pk, ns) 311.04 squelched 77.76 0 0000 xxx < 0.5 311.04 normal 77.76 0 0001 xxx < 0.5 98.304 12 x e1 24.576 0 0010 xxx < 0.5 131.072 16 x e1 32.768 0 0011 xxx < 0.5 148.224 24 x ds1 37.056 0 0100 xxx < 0.5 98.816 16 x ds1 24.704 0 0101 xxx < 0.5 274.944 2 x e3 68.736 0 0110 xxx < 0.5 178.944 ds3 44.736 0 0111 xxx < 0.5 100.992 4 x 6312 khz 25.248 0 1000 xxx < 0.5 250.000 gbe 16 62.500 0 1001 xxx < 0.5 98.304 t0 12 x e1 ? 1 xxxx 000 < 2 131.072 t0 16 x e1 ? 1 xxxx 010 < 2 148.224 t0 24 x ds1 ? 1 xxxx 100 < 2 98.816 t0 16 x ds1 ? 1 xxxx 110 < 2 100.992 4 x 6312khz ? 1 xxxx 111 < 2
DS3101 stratum 3/3e timing card ic 44 of 149 table 7-12. oc1 to oc7 ou tput frequency selection frequency register value (1) oc1 oc2 oc3 oc4 oc5 oc6 oc7 0000 disabled disabled disabled disabled disabled disabled disabled 0001 2khz 2khz 2khz 2k hz 2khz 2khz 2khz 0010 8khz 8khz 8khz 8k hz 8khz 8khz 8khz 0011 digital2 digital2 digital2 digit al2 digital2 t0 apll/2 digital2 0100 digital1 digital1 digital1 digit al1 digital1 digital1 t0 apll/2 0101 t0 apll/48 t0 apll/48 t0 apll/48 t0 apll/48 t0 apll/48 t0 apll/1 t0 apll/48 0110 t0 apll/16 t0 apll/16 t0 apll/16 t0 apll/16 t0 apll/16 t0 apll/16 t0 apll/16 0111 t0 apll/12 t0 apll/12 t0 apll/12 t0 apll/12 t0 apll/12 t0 apll/12 t0 apll/12 1000 t0 apll/8 t0 apll/8 t0 apll/8 t0 apll/8 t0 apll/8 t0 apll/8 t0 apll/8 1001 t0 apll/6 t0 apll/6 t0 apll/6 t0 apll/6 t0 apll/6 t0 apll/6 t0 apll/6 1010 t0 apll/4 t0 apll/4 t0 apll/4 t0 apll/4 t0 apll/4 t0 apll/4 t0 apll/4 1011 t4 apll/64 t4 apll/64 t4 apll/64 t4 apll/2 t4 apll/2 t4 apll/64 t4 apll/64 1100 t4 apll/48 t4 apll/48 t4 apll/48 t4 apll/48 t4 apll/48 t4 apll/48 t4 apll/48 1101 t4 apll/16 t4 apll/16 t4 apll/16 t4 apll/16 t4 apll/16 t4 apll/16 t4 apll/16 1110 t4 apll/8 t4 apll/8 t4 apll/8 t4 apll/8 t4 apll/8 t4 apll/8 t4 apll/8 1111 t4 apll/4 t4 apll/4 t4 apll/4 t4 apll/4 t4 apll/4 t4 apll/4 t4 apll/4 note 1: the value of the ofreqn field (in the ocr1 through ocr4 registers) corresponding to output clock ocn. table 7-13. possible fre quencies for oc1 to oc7 jitter (typ) frequency (mhz) t0 dpll mode t4 dpll mode t4 apll source ofreqn setting rms (ps) pk-pk (ns) 2khz 77.76mhz, analog ? ? 0001 60 0.6 2khz any digital feedback 0001 1400 5.0 8khz 77.76mhz, analog 0010 60 0.6 8khz any digital feedback 0010 1400 5.0 1.536 not oc4 or oc5 12 x e1 t4 dpll 1011 55 0.6 1.536 not oc4 or oc5 t0 12 x e1 1011 250 1.5 1.544 via digital1, not oc7 77.76mhz, analog 0100 3800 13 1.544 via digital2, not oc6 77.76mhz, analog 0011 3800 13 1.544 via digital1, not oc7 any digital feedback 0100 3800 18 1.544 via digital2, not oc6 any digital feedback 0011 3800 18 1.544 not oc4 or oc5 16 x ds1 t4 dpll 1011 140 1.2 1.544 not oc4 or oc5 t0 16 x ds1 1011 275 1.9 1.578 not oc4 or oc5 4 x 6312khz t4 dpll 1011 240 1.5 1.578 not oc4 or oc5 t0 4x6312khz 1011 260 1.8 2.048 not oc6 12 x e1 mode 0101 425 2.6 2.048 via digital1, not oc7 77.76mhz, analog 0100 3800 13 2.048 via digital2, not oc6 77.76mhz, analog 0011 3800 13 2.048 via digital1, not oc7 any digital feedback 0100 3800 18 2.048 via digital2, not oc6 any digital feedback 0011 3800 18 2.048 12 x e1 t4 dpll 1100 55 0.6 2.048 t0 12 x e1 1100 250 1.5 2.048 not oc4 or oc5 16 x e1 t4 dpll 1011 50 0.5 2.048 not oc4 or oc5 t0 16 x e1 1011 350 2.4 2.059 not oc6 16 x ds1 0101 435 2.8 2.059 16 x ds1 t4 dpll 1100 140 1.2 2.059 t0 16 x ds1 1100 275 1.9 2.104 not oc6 4 x 6312 khz 0101 340 2.3 2.104 4 x 6312khz t4 dpll 1100 240 1.8 2.104 t0 4x6312khz 1100 260 1.8 2.316 not oc4 or oc5 24 x ds1 t4 dpll 1011 150 1.0 2.316 not oc4 or oc5 t0 24 x ds1 1011 400 2.8 2.731 not oc6 16 x e1 0101 380 2.6 2.731 16 x e1 t4 dpll 1100 50 0.5 2.731 t0 16 x e1 1100 350 2.4
DS3101 stratum 3/3e timing card ic 45 of 149 jitter (typ) frequency (mhz) t0 dpll mode t4 dpll mode t4 apll source ofreqn setting rms (ps) pk-pk (ns) 2.796 not oc4 or oc5 ds3 t4 dpll 1011 80 0.7 3.088 not oc6 24 x ds1 0101 400 2.8 3.088 via digital1, not oc7 77.76mhz, analog 0100 3800 13 3.088 via digital2, not oc6 77.76mhz, analog 0011 3800 13 3.088 via digital1, not oc7 any digital feedback 0100 3800 18 3.088 via digital2, not oc6 any digital feedback 0011 3800 18 3.088 24 x ds1 t4 dpll 1100 150 1.0 3.088 t0 24 x ds1 1100 400 2.8 3.728 ds3 t4 dpll 1100 80 0.7 3.90625 not oc4 or oc5 gbe 16 t4 dpll 1011 70 0.6 4.096 via digital1, not oc7 77.76 mhz, analog 0100 3800 13 4.096 via digital2, not oc6 77.76 mhz, analog 0011 3800 13 4.096 via digital1, not oc7 any digital feedback 0100 3800 18 4.096 via digital2, not oc6 any digital feedback 0011 3800 18 4.296 not oc4 or oc5 2 x e3 t4 dpll 1011 350 2.0 4.86 not oc4 or oc5 77.76mhz t4 dpll 1011 60 0.6 5.2083 gbe 16 t4 dpll 1100 70 0.6 5.728 2 x e3 t4 dpll 1100 350 2.0 6.144 12 x e1 0110 425 2.6 6.144 12 x e1 t4 dpll 1101 55 0.6 6.144 t0 12 x e1 1101 250 1.5 6.176 16 x ds1 0110 435 2.8 6.176 via digital1, not oc7 77.76mhz, analog 0100 3800 13 6.176 via digital2, not oc6 77.76mhz, analog 0011 3800 13 6.176 via digital1, not oc7 any digital feedback 0100 3800 18 6.176 via digital2, not oc6 any digital feedback 0011 3800 18 6.176 16 x ds1 t4 dpll 1101 140 1.2 6.176 t0 16 x ds1 1101 275 1.9 6.312 4 x 6312khz 0110 340 2.3 6.312 via digital 2, not oc6 77.76mhz, analog 0011 3800 13 6.312 via digital 2, not oc6 any digital feedback 0011 3800 18 6.312 4 x 6312khz t4 dpll 1101 240 1.8 6.312 t0 4 x 6312khz 1101 260 1.8 6.48 not oc6 77.76mhz, analog 0101 60 0.6 6.48 not oc6 77.76mhz, digital 0101 60 0.6 6.48 77.76 mhz t4 dpll 1100 60 0.6 8.192 12 x e1 0111 425 2.6 8.192 16 x e1 0110 380 2.6 8.192 via digital1, not oc7 77.76 mhz, analog 0100 3800 13 8.192 via digital2, not oc6 77.76 mhz, analog 0011 3800 13 8.192 via digital1, not oc7 any digital feedback 0100 3800 18 8.192 via digital2, not oc6 any digital feedback 0011 3800 18 8.192 16 x e1 t4 dpll 1101 50 0.5 8.192 t0 16 x e1 1101 350 2.4 8.235 16 x ds1 0111 435 2.8 8.416 4 x 6312khz 0111 340 2.3 9.264 24 x ds1 0110 400 2.8 9.264 24 x ds1 t4 dpll 1101 150 1.0 9.264 t0 24 x ds1 1101 400 2.8 10.923 16 x e1 0111 380 2.6 11.184 ds3 t4 dpll 1101 80 0.7 12.288 12 x e1 1000 425 2.6 12.288 12 x e1 t4 dpll 1110 55 0.6 12.288 t0 12 x e1 1110 250 1.5 12.352 24 x ds1 0111 400 2.8 12.352 16 x ds1 1000 435 2.8 12.352 16 x ds1 t4 dpll 1110 140 1.2 12.352 t0 16 x ds1 1110 275 1.9 12.352 via digital1, not oc7 77.76mhz, analog 0100 3800 13
DS3101 stratum 3/3e timing card ic 46 of 149 jitter (typ) frequency (mhz) t0 dpll mode t4 dpll mode t4 apll source ofreqn setting rms (ps) pk-pk (ns) 12.352 via digital2, not oc6 77.76mhz, analog 0011 3800 13 12.352 via digital1, not oc7 any digital feedback 0100 3800 18 12.352 via digital2, not oc6 any digital feedback 0011 3800 18 12.624 4 x 6312khz 1000 340 2.3 12.624 4 x 6312khz t4 dpll 1110 240 1.8 12.624 t0 4x6312khz 1110 260 1.8 15.625 gbe 16 t4 dpll 1101 70 0.6 16.384 12 x e1 1001 425 2.6 16.384 16 x e1 1000 380 2.6 16.384 16 x e1 t4 dpll 1110 50 0.5 16.384 t0 16 x ds1 1110 275 1.9 16.384 via digital1, not oc7 77.76mhz, analog 0100 3800 13 16.384 via digital2, not oc6 77.76mhz, analog 0011 3800 13 16.384 via digital1, not oc7 any digital feedback 0100 3800 18 16.384 via digital2, not oc6 any digital feedback 0011 3800 18 16.469 16 x ds1 1001 435 2.8 16.832 4 x 6312khz 1001 340 2.3 17.184 2 x e3 t4 dpll 1101 350 2.0 18.528 24 x ds1 1000 400 2.8 18.528 24 x ds1 t4 dpll 1110 150 1.0 18.528 t0 24 x ds1 1110 400 2.8 19.44 77.76mhz, analog 0110 60 0.6 19.44 77.76mhz, digital 0110 60 0.6 19.44 77.76 mhz t4 dpll 1101 60 0.6 21.845 16 x e1 1001 380 2.6 22.368 ds3 t4 dpll 1110 80 0.7 24.576 12 x e1 1010 425 2.6 24.576 12 x e1 t4 dpll 1111 55 0.6 24.576 t0 12 x e1 1111 250 1.5 24.704 24 x ds1 1001 400 2.8 24.704 16 x ds1 1010 435 2.8 24.704 16 x ds1 t4 dpll 1111 140 1.2 24.704 t0 16 x ds1 1111 275 1.9 25.000 gbe 16 t4 dpll 1100 70 0.6 25.248 4 x 6312khz 1010 340 2.3 25.248 4 x 6312khz t4 dpll 1111 240 1.8 25.248 t0 4x6312khz 1111 260 1.8 25.92 77.76mhz, analog 0111 60 0.6 25.92 77.76mhz, digital 0111 60 0.6 31.25 gbe 16 t4 dpll 1110 70 0.6 32.768 16 x e1 1010 380 2.6 32.768 16 x e1 t4 dpll 1111 50 0.5 32.768 t0 16 x e1 1111 350 2.4 34.368 2 x e3 t4 dpll 1110 350 2.0 37.056 24 x ds1 1010 400 2.8 37.056 24 x ds1 t4 dpll 1111 150 1.0 37.056 t0 24 x ds1 1111 400 2.8 38.88 77.76mhz, analog 1000 60 0.6 38.88 77.76mhz, digital 1000 60 0.6 38.88 77.76mhz t4 dpll 1110 60 0.6 44.736 ds3 t4 dpll 1111 80 0.7 49.152 oc6 and oc7 only 12 x e1 0011/0100 425 2.6 49.152 oc4 and oc5 only 12 x e1 t4 dpll 1011 55 0.6 49.152 oc4 and oc5 only t0 12 x e1 1011 250 1.5 49.408 oc6 and oc7 only 16 x ds1 0011/0100 435 2.8 49.408 oc4 and oc5 only 16 x ds1 t4 dpll 1011 140 1.2 49.408 oc4 and oc5 only t0 16 x ds1 1011 275 1.9 50.496 oc6 and oc7 only 4 x 6312khz 0011/0100 340 2.3 50.496 oc4 and oc5 only 4 x 6312khz t4 dpll 1011 240 1.8
DS3101 stratum 3/3e timing card ic 47 of 149 jitter (typ) frequency (mhz) t0 dpll mode t4 dpll mode t4 apll source ofreqn setting rms (ps) pk-pk (ns) 50.496 oc4 and oc5 only t0 4 x 6312khz 1011 260 1.8 51.84 77.76mhz, analog 1001 60 0.6 51.84 77.76mhz, digital 1001 60 0.6 62.50 gbe 16 t4 dpll 1111 70 0.6 65.536 oc6 and oc7 only 16 x e1 0011/0100 380 2.6 65.536 oc4 and oc5 only 16 x e1 t4 dpll 1011 50 0.5 65.536 oc4 and oc5 only t0 16 x e1 1011 350 2.4 68.736 2 x e3 t4 dpll 1111 350 2.0 74.112 oc6 and oc7 only 24 x ds1 0011/0100 400 2.8 74.112 oc4 and oc5 only 24 x ds1 t4 dpll 1011 150 1.0 74.112 oc4 and oc5 only t0 24 x ds1 1011 400 2.8 77.76 77.76mhz, analog 1010 60 0.6 77.76 77.76mhz, digital 1010 60 0.6 77.76 77.76mhz 1111 60 0.6 89.472 oc4 and oc5 only ds3 t4 dpll 1011 80 0.7 98.304 oc6 only 12 x e1 0101 425 2.6 98.816 oc6 only 16 x ds1 0101 435 2.8 100.992 oc6 only 4 x 6312khz 0101 340 2.8 125.000 oc5 only gbe 16 t4 dpll 1011 70 0.6 131.072 oc6 only 16 x e1 0101 380 2.6 137.472 oc4 and oc5 only 2 x e3 t4 dpll 1011 350 2.0 148.224 oc6 only 24 x ds1 0101 400 2.8 155.52 oc6 and oc7 only 77.76mhz, analog 0011/0100 60 0.6 155.52 oc6 and oc7 only 77.76mhz, digital 0011/0100 60 0.6 155.52 oc4 and oc5 only 77.76mhz t4 dpll 1011 60 0.6 311.04 oc6 only 77.76mhz, analog 0101 60 0.6 311.04 oc6 only 77.76mhz, digital 0101 60 0.6 7.8.2.4 oc8 and oc9 configuration output clocks oc8 and oc9 are generated by digital frequency synthesis (dfs) from either the t0 path or the t4 path, depending on the setting of the oc89 bit in mcr4 . when generated from the t4 path (oc89 = 0), if asquel = 1 in t4cr1 then oc8 and oc9 are automatically squelched when t4 has no valid input references. oc8 is always a 64khz composite clock transmitter and th erefore does not require any frequency configuration. being 64khz, oc8 can be divided down di rectly from the source dfs block? s input clock. the jitter on oc8 can range from 13ns to 17ns, depending on whether the dpll is in analog or digital feedback mode. see section 7.10.2 for additional oc8 configuration details. oc9 is always a ds1 or e1 clock. oc9 is enabled by setting oc9en = 1 in the ocr4 register, and it is configured for ds1 or e1 with the oc9son bit in t4cr1 (when oc89 = 0) or with the sonsdh bit in mcr3 (when oc89 = 1). oc9 must synthesized, rather than directly divided do wn, from the source dfs block?s input clock. the jitter on oc9 is therefore a function of the jitter on the input clock and the jitter generated during synthesis. oc9 jitter can range from 11ns to 20ns. 7.8.2.5 oc10 and oc11 configuration output clocks oc10 and oc11 are always generated from the t0 path. oc10 is enabled by setting oc10en = 1 in the ocr4 register, while oc11 is enabled by setting oc11en = 1 in ocr4 . when 8kpul = 0 in fscr1 , oc10 is configured as an 8khz clock with 50% duty cycle. when 8kpul = 1, oc10 is an 8khz frame sync that pulses low once every 125 s with pulse width equal to one cycle of output clock oc3. when 8kinv = 1 in fscr1 , the clock or pulse polarity of oc10 is inverted. when 2kpul = 0 in fscr1 , oc11 is configured as an 2khz clock with 50% duty cycle. when 2kpul = 1, oc11 is a 2khz frame sync that pulses low once every 500 s with pulse width equal to one cycle of output clock oc3. when 2kinv = 1 in fscr1 , the clock or pulse polarity of oc11 is inverted.
DS3101 stratum 3/3e timing card ic 48 of 149 if either 8kpul = 1 or 2kpul = 1, then output clock oc3 must be generated from the t0 dpll and must be configured for a frequency of 1.544mhz or higher or the oc10/oc11 pulses may not be generated correctly. figure 7-6 shows how the 8kpul and 8kinv control bits affe ct the oc10 output. the 2kpul and 2kinv bits have an identical effect on oc11. figure 7-6. oc10 8khz options oc3 output clock oc10, 8kpul=0, 8kinv=0 oc10, 8kpul=0, 8kinv=1 oc10, 8kpul=1, 8kinv=0 oc10, 8kpul=1, 8kinv=1 7.9 equipment redunda ncy configuration most high-reliability sonet/sdh syst ems require two identical timing ca rds for equipment redundancy. the DS3101 directly supports this requirement. in such a sy stem one timing cards is designated the master while the other is designated the slave. the rest of the system, outside the timing cards, is set up to take timing from the master normally, but to automatically switch to taking timi ng from the slave if the master fails. to avoid excessive phase transients when switching between master timing and slave timing, the clocks from the master and the slave must be frequency locked and usually phase locked as well. to accomplish this requires a method involving both static configuration and ongoing over sight by system software. the elemen ts of this methodology are listed in table 7-14 . table 7-14. equipment redundancy methodology 1. the various clock sources available in the system should be wired to the same pins on the slave as on the master, except: a. one output clock from the master device sh ould be wired to an input clock on the slave. b. one output clock from the slave device s hould be wired to an input clock on the master. 2. the input clock priorities ( ipr registers) on master and slave should be identical, for both t0 and t4 paths, except: a. the master output clock is the highest priority input on the slave (1) b. the slave output clock is disabled (priority 0) on the master this ensures that the frequency of the sl ave matches the frequency of the master. 3. any input declared invalid in one device ( valsr registers) must be marked invalid by software in the other device ( valcr registers). this and item 2 together en sure that when the master is performing properly, the slave locks to the master, and when the ma ster fails, the slave loc ks to the input clock the master was previously locked to. 4. the slave?s t0 dpll bandwidth should be set higher than the master?s ( t0lbw , t0abw registers) to ensure that the slave follows any transients coming from the master. (70hz is recommended.) 5. phase build-out should be disabled ( mcr10 :pboen = 0 and phmon :pmpben = 0) on the slave when it is locked to the master to ensure that the slave maintains phase lock with the master. this also allows the use of phase offset ( offset registers) to compensate for delays between master and slave. 6. revertive mode should be enabled on the slave (revert = 1 in mcr3 ) to ensure the slave switches from any other reference to the master as soon as the master?s clock is valid. note 1: this must be done for the slave?s t0 path, but is not necessary for the slave?s t4 path. in the slave?s t4 path the input cloc k priorities should match those of the master except t he input connected to the master?s output cl ock should be disabled. this causes the sl ave?s t4 path to only lock to external references.
DS3101 stratum 3/3e timing card ic 49 of 149 7.9.1 master-slave pin feature some of the elements of redun dancy configuration listed in table 7-14 are automatically handled in the device when the master-slave pin feature is used (mastslv). wh en this feature is support ed in a system, one output clock of the master device must be wir ed to input clock ic11 on the slave devi ce, and one output clock of the slave device should be wired to ic11 on the mast er device. this cross-wi ring allows the system to dynamically configure either device as master and the other as slave. when the mastslv pin is wired low on one device, that dev ice is configured as the sl ave. the other device must be configured as the master by wiring its mastslv pi n high. in each device the st ate of the mastslv pin is always indicated in the read-only mastslv bit in register mcr3 . the slave device (mastslv = 0) is au tomatically configured as follows: the priority of input clock ic11 is set to 1 (highest) ( ipr6 :pri11[3:0] = 0001). phase build-out is disabled ( mcr10 :pboen = 0). revertive mode is enabled ( mcr3 :revert = 1). t0 dpll bandwidth is forced to the acquisition setting (i.e., to the setting in the t0abw register, which should be set to a high bandwidth by software). in the master device (mastslv = 1), n one of these settings are forced to spec ific values. rather, each setting is configured as needed for normal operation of the system . during configuration, software should configure the master to disable (priority 0) input clock ic11 and should conf igure the remaining input clock priorities identically in master and slave. during operation, so ftware must maintain matching input clock priorities, as described in item 3 of table 7-14 . the master-slave pin feature is optional and can be dis abled by wiring the mastslv pin high on both devices. if this feature is disabled, all the el ements of equipment redundancy listed in table 7-14 must be configured and maintained by software. 7.9.2 master-slave output clock phase alignment when the t0 dpll is locked to a selected reference with frequency f, any output clocks derived from t0 with frequency f are phase aligned with the selected reference (i f phase build-out is disabled). any output clocks derived from t0 with frequency greater than f are ?falling edge aligned? with the fre quency-f output clock. any output clocks derived from t0 with frequency less than f may or may not be aligned, depending on whether or not their frequencies are integer sub-multiples of f. these statements also apply to output clocks derived from the t4 dpll. given this information, if master an d slave devices are cross-wi red with 19.44mhz clocks, for example, the output clocks at n x 19.44mhz (n = 1, 2, 4, 8, or 16) from the two devices are phase-aligned with one another. output clocks at lower frequencies (6.48mhz, 1.544mhz, 2.048mhz , 2khz, 8khz, etc.) from the two devices would not necessarily be phase aligned. in many systems, lack of phase alignment bet ween the two devices at these clock rates is not an issue. in some system s, however, the 2khz and/or 8khz clocks of the two devices must be aligned to avoid framing errors during swit chover between master and slave. one way to align the 2khz and/or 8khz clocks of the master and slave devices is to config ure the slave to lock to a 2khz or 8khz output of the master. another way is to use the sync2k input as described in section 7.9.3 .
DS3101 stratum 3/3e timing card ic 50 of 149 7.9.3 master-slave frame and multiframe alignment with the sync2k pin with this method of aligning the 2khz and 8khz clocks of the master and slave devic es, both a higher-speed clock (such as 6.48mhz or 19.44mhz) and a frame-sync signal (n ormally 2khz) from the master are passed to the slave (and vice versa when their roles are reversed). the highe r-speed clock from the master is connected to a regular input clock pin on the slave, such as ic11, while the fr ame-sync signal from the master is connected to the sync2k pin on the slave. the slave locks to the highe r-speed clock and samples the frame-sync signal on sync2k. the slave then uses the sync2k signal to falling- edge align some or all of the output clocks. only the falling edge of sync2k has significance. a 4khz or 8khz clock can also be used on sync2k without any changes to the register configuration, but onl y output clocks of 8khz and above are aligned in this case. phase build-out should be disabled on the slave (pboen = 0 in mcr10 ), and the higher-speed input clock on the slave must be configured for direct-lock mode ( icr :divn = 0 and lock8k = 0). sampling. by default the sync2k signal is first sampled on the rising edge of the selected reference. this gives the most margin, given that the sync2k signal is falling- edge aligned with the selected reference since both come from the master device. the expected timing of sync2k with respect to the sampling clock can be adjusted from 0.5 cycles early to 1 cycle late using the fscr2 :phase[1:0] field. resampling. the sync2k signal is then resampled by an in ternal clock derived from the t0 dpll. the resampling resolution is a function of the frequency of the selected reference and fscr2 :ocn. when ocn = 0, the resampling resolution is 6.48mhz, which gives the high est sampling margin and also aligns clocks at 6.48mhz and multiples thereof. when ocn = 1, if the selected reference is 19.44mhz then the resampling resolution is 19.44mhz. if the selected reference is 38.88mhz then the resampling resolution is 38.88mhz. the selected reference must be either 19.44mhz or 38.88mhz. sync2k enable. the sync2k signal is only allowed to align output clocks if the t0 dpll is locked and sync2k is enabled and qualified. sync2k can be enabled automatically or manually. when mcr3 :aefsen = 1, sync2k is enabled automatically when efsen = 1 and the t0 dpll is locked to the input clock specified by fscr3 :source[3:0]. when aefsen = 0, sync2k is enabled manually when mcr3 :efsen = 1 and disabled when efsen = 0. in manual mode when efsen = 1, fscr3 :source[3:0] is ignored and sync2k is always enabled regardless of which input clock is the selected reference. sync2k qualification. sync2k is qualified when it has consistent phase and correct frequency. specifically, sync2k is qualified when its significant edge has been fo und at exact 2khz boundaries (when resampled as described above) for 64 sync2k cycles in a row. sync2k is disqualified when one signi ficant edge is not found at the 2khz boundary. output clock alignment. when t0 is locked and sync2k is enabled and qualified, sync2k can be used to falling-edge align the t0-derived output clocks. output clocks oc10 and oc11 share a 2khz alignment generator, while the rest of the t0-derived output clocks share a second 2khz alignment generator. when sync2k is not enabled or is not qualified, these 2hz alignment generator s free-run with their existing 2khz alignments. when sync2k is enabled and qualified, the oc10/oc11 2khz al ignment generator is always synchronized by sync2k, and therefore oc10 and oc11 are always falling-edge aligned with sync2k. when fscr2 :indep = 0, the t0 2khz alignment generator is also synchronized with the oc10/oc11 2khz alignment generator to falling-edge align all t0-derived output clocks with sync2k. when in dep = 1, the t0 2khz alignment generator is not synchronized with the oc10/oc11 2khz alignment generator and conti nues to free-run with its existing 2khz alignment. this avoids any disturbance on the t0-derived output cl ocks when sync2k has a change of phase position. frame sync monitor. the frame sync monitor signal opstate :fsmon operates in two modes, depending on the setting of the enable bit ( mcr3 :efsen). when efsen = 1 (sync2k enabled) the fsmon bit is set when sync2k is not qualified and cleared when sync2k is qualified. if sync2k is disqualified then both 2khz alignment generators ar e immediately disconnected from sync2k to avoid phase movement on the t0-derived outputs clocks. when opstate :fsmon is set, the latched status bit msr3 :fsmon is also set, which can cause an interrupt if enabled. if sync2k immediately stabilizes at a new phase and proper fr equency, then it is requalified after 64 2khz cycles (nominally 32ms). unless system software intervenes, after sync2k is requalifi ed the 2khz alignment generat ors will synchronize with sync2k?s new phase alignment, causing a sudden phase mo vement on the output cloc ks. system software can
DS3101 stratum 3/3e timing card ic 51 of 149 avoid this sudden phase movement on the output clocks by responding to the fsmon interrupt within the 32ms window with appropriate action, which might include disabling sync2k ( mcr3 :efsen = 0) to prevent the resynchronization of the 2khz alignment generators with sync2k, forcing the slave into holdover ( mcr1 :t0state = 010) to avoid affecting the output clocks with any other phase hits, and possibly even disabling the master and promoting the sl ave to master (see section 7.9.1 ) since the 2khz signal fr om the master should not have such phase movements. when efsen = 0 (sync2k disabled) opstate :fsmon is set when the negative edge of the re-sampled sync2k signal is outside of the window determined by fscr3 :monlim relative to the oc11 negative edge (or positive edge if oc11 is inverted) and clear when within the window. when opstate :fsmon is set, the latched status bit msr3 :fsmon is also set, which can cause an interrupt if enabled. other frame sync configuration options. oc10 and oc11 are always produced from the t0 path. output clocks oc1 to oc7 can also be configured as 2khz or 8khz outputs, derived from either the t0 path or the t4 path (as specified by the 2k8ksrc bit in fscr1 ). if needed, the t4 dpll can be used as a separate dpll for the frame sync path by configuring it for a 2khz input and 2khz and/or 8 khz frame sync outputs.
DS3101 stratum 3/3e timing card ic 52 of 149 7.10 composite clock receivers and transmitter by default, input clocks ic1 and ic2 are configured as compos ite clock receivers. output clock oc8 is a dedicated composite clock transmitter. these i/os support the following key composite clock variations: gr-378 composite clock ( note 1 ) g.703 centralized clock ( note 2 ) g.703 japanese synchronization interface ( note 3 ) note 1: complies with telcordia gr-378 composite clock a nd g.703 section 4.2.2 centralized clock option b). note 2: complies with itu_t g.703 section 4.2.2 centralized clock options a) and g.703 section 4.2.3 contradirectional interface clock. note 3: complies with itu_t g.703 appendix ii.1 options a) and option b) japanese sync hronization interfaces. composite clock (cc) signals provide both bit and byte sync hronization for equipment with ds0 connections. in all cc variations, the signal is a 64khz ami signal with an embedded 8khz clock indicated by a deliberate bipolar violation (bpv) every 8 clock cycles. the option b) japanese synchronization interface in g.703 appendix ii.1 also has an embedded 400hz clock indicated by a bpv removed every 400hz. details about the several composite clock variations are described in t he following paragraphs and summarized in table 7-15 . gr-378 composite clock. as shown in table 7-16 and figure 7-7 , the gr-378 composite clock signal has a 5/8 duty-cycle square pulse and a 133 line impedance. the g.703 section 4.2.2 option b) centralized clock specifications are nearly identical to the gr-378 composit e clock, with the exception of line termination impedance (110 for g.703 vs. 133 for gr-378). g.703 centralized clock and other 64khz + 8khz timing signals. g.703 section 4.2.2 defines two centralized clock types, option a) and option b). option b) is di scussed in the gr-378 paragraph above. as shown in table 7-17 , the option a) centralized clock has a 50% duty cycle and a 110 line impedance. g.703 also specifies three other timing signals that have characteristics and specific ations that are nearly identic al to those of centralized clock option a). these other signals are (1) the timing sign al in the 64kbps contradirectional interface defined in g.703 section 4.2.3, (2 ) the 64khz + 8khz ja panese timing signal defined in g.703 appendix ii.1, and (3) the 64khz + 8khz + 400hz japane se timing signal defined in g.703 appendix ii.1 (which has the 8khz bpv removed every 400hz). table 7-17 tabulates the requirements for each of these signals. table 7-15. composite clock variations variation line impedance ( 0) pulse amplitude (v) nominal duty cycle bpvs composite clock, gr-378 133 2.7 to 5.5 5/8 8khz centralized clock, g.703 4.2.2 option b) 110 3.0 0.5 5/8 8khz centralized clock, g.703 4.2.2 option a) 110 1.0 0.1v 50% 8khz japanese sync interface, g.703 appendix ii.1 option a) 110 1 0.1 50% 8khz japanese sync interface, g.703 appendix ii.1 option b) 110 1 0.1 50% 8khz, but removed at 400hz contradirectional interface clock, g.703 4.2.3 120 1.0 0.1 50% 8khz
DS3101 stratum 3/3e timing card ic 53 of 149 7.10.1 ic1 and ic2 receivers input clocks ic1 and ic2 can be either composite clock receivers (via the ic1a and ic2a pins) or standard cmos/ttl inputs (via the ic1 and ic2 pins). configuration bits mcr5 :ic1sf and ic2sf specify the signal format for ic1 and ic2, respectively. when these inputs are conf igured as composite clock (c c) receivers, they can directly receive incoming ami-coded 64khz cc signals, including those with the pre-emphasis described in gr- 378 section 4.2. see the electrical specifications in table 10-6 , and the recommended external components in figure 10-3 . each cc receiver derives an 8khz clock from the 8khz co mponent of the incoming cc signal. it is this 8khz clock that is forwarded to the input clock monitoring and select ion circuitry. the falling edge of this 8khz clock can be configured to coincide with the l eading edge of the 8khz bpv or the leading edge of the pulse following the bpv, as specified by the ccedge field in the mcr5 register. incoming composite clock signals are monitored for loss-o f-signal and ami violations. when either of these signal conditions occurs, a corresponding latched status bit is set in register msr3 . when set, these status bits can cause an interrupt request on the intreq pin if enabled by the corresponding bits in ier3 . loss of signal is declared when no pulses are detected in the incoming signal in a 32 s period (i.e., after two missing pulses, voltage threshold v los = 0.2v typical). the amplitude threshold for detecti ng a pulse is 0.2v. an ami violation is declared when a deviation from the expected pat tern of seven ones followe d by a bpv occurs in each of two consecutive 8-bit periods. when mcr5 :biterr = 1, single-bit violations of t he one-bpv-in-eight pattern are considered irregularities by the corresponding activity monito r and increment the leaky bucket accumulator. when mcr5 :ami = 1, the detection of an ami violation automatic ally invalidates the offending clock. when mcr5 :los = 1, the detection of loss-of-signal automatica lly invalidates the offending clock. in addition, register msr4 has latched status bits that indicate t he absence of the 8khz component and the 400hz component. in some networks the 8khz component is re moved to signal an alarm condition. if the bpvs that indicate the 8khz component cannot be found in the incoming signal in a 500 s period (four 8khz cycles), then msr4 :icxno8 is set to indicate the fact. this can cause an interrupt on the intreq pin if enabled by the corresponding bit in ier4 . this logic is always active. if the lack of the 8khz component is not an alarm signal in the synchronization network, then ier4 :icxno8 can be set to 0 to disable the interrupt, and msr4 :icxno8 can be ignored. if the 8khz component is not present in the signal , then the cc receiver does no t forward an 8khz clock to the input monitoring logic. the input monitoring lo gic then declares that input clock invalid. if the missing bpvs that indicate the 40 0hz component cannot be found in a 5ms period (two 400hz cycles), then msr4 :icxno4 is set. this can cause an interrupt on the intreq pin if enabled by the corresponding bit in ier4 . this logic is always active. if the 400hz component is not expected to be present in the signal, then ier4 :icxno4 can be set to 0 to disable the interrupt, and msr4 :icxno4 can be ignored. when the 8khz component is entirely missing from the incoming signal, the ami status bit in msr3 is continually set, and can cause repeated interrupts if enabled. therefore, in networks where the lack of the 8khz component is used as an alarm signal, after msr4 :icxno8 is set to indicate that the 8khz component is missing, the interrupt for msr3 :amix should be disabled until icxno8 goes low, indica ting the 8khz component is present again. also, since the 8khz component is the clock that is forwarded to the input clock monitor, if the 8khz component is missing in the incoming signal, the input clock monitor auto matically invalidates the cl ock. if the 400hz component is missing, however, the ami status bit is not set and the clock is not invalidated. 7.10.2 oc8 transmitter output clock oc8 is a dedicated co mposite clock transmitter. see t he electrical specifications in table 10-6 , and the recommended external components in figure 10-3 . oc8 is a differential output consisting of pins oc8pos and oc8neg. these pins are enabled/disabled by ocr4 :oc8en. either 50% or 5/8 duty cycle can be selected by setting t4cr1 :oc8duty appropriately. in some networks t he 8khz component (i.e., the one bpv every eight cycles) is removed to signal an alar m condition; the 8khz component of the oc8 signal can be removed as needed by setting mcr8 :oc8no8 = 1. when the selected reference is either ic1 or ic 2 and that input is configured in ami/cc mode ( mcr5 :icxsf = 0), and the signal on that input has an 8khz component ( msr4 :icxno8 = 0), then the output bpvs on oc8 (the 8khz component) is closely aligned (within a few s) to the input bpvs but may be of opposite polarity.
DS3101 stratum 3/3e timing card ic 54 of 149 to support the g.703 a ppendix ii.1 option b) japanese synchronization interface, the 400hz component (i.e., the removed bpv every 160 cycles) can be enabled by setting mcr8 :oc8400 = 1. if the selected reference is either ic1 or ic2 and that input is configured in ami/cc mode ( mcr5 :icxsf = 0) and the signal on that input has a 400 hz component ( msr4 :icxno4 = 0), then oc8?s 400hz component is aligned with the input 400 hz component but may be the opposite polarity. otherwise, the 400hz com ponent for oc8 is divided down from oc8?s 8khz component. setting oc8400 = 1 has no effect if oc8no8 = 1. see section 7.8.2.4 for additional oc8 configuration details. table 7-16. gr-378 composite clock interface specification parameter specification nominal line rate 64khz with 8khz bipolar violation. line-rate accuracy accuracy of the network clock. line code bipolar (ami), return-t o-zero, with 5/8 duty cycle. medium a shielded, balanced twisted pair. test load impedance the resistive test load of 133 ( 5%) shall be used at the inte rface for evaluation of the pulse shape and the electrical parameters. pulse amplitude the amplitude of an isol ated pulse shall be between 2.7v and 5.5v. pulse shape the shape of an isolated pulse shall be rectangular with rise and fall times less than 0.5 s such that the pulse fits the shape of the mask in figure 7-7 . pulse imbalance the ratio of the amplitudes of the positiv e and negative pulses shall be from 0.95 to 1.05. the ratio of the widths of the positive and negative pulses shall be from 0.95 to 1.05. dc power no dc power shall be applied to the interface. figure 7-7. gr-378 com posite clock pulse mask -0.2 0 0.2 0.4 0.6 0.8 1.0 1.2 0 0.2 0.4 0.6 0.8 1.0 time (ui) normalized amplitude time (ui) minimum normalized amplitude minimum normalized amplitude 0 -0.05 1.05 0.032 0.95 1.05 0.625 -0.05 1.05 0.657 -0.05 0.05 1 -0.05 0.05 table 7-17. g.703 synchroniza tion interfaces specification parameter specification pulse shape nominally rectangular, with rise and fall times less than 1 s. transmission media symmetric pair cable. nominal test load impedance 110 resistive (centralized clock and appendix ii japanese signals). 120 resistive (contradirectional interface). peak voltage of a mark (pulse) 1.0v 0.1v peak voltage of a space (no pulse) 0v 0.1v nominal pulse width 7.8 s 0.78 s pulse imbalance the ratio of the amplitudes of t he positive and negative pulses shall be from 0.95 to 1.05. the ratio of the widths of the posi tive and negative pulses shall be from 0.95 to 1.05. alarm condition for received signal amplitude no alarm for pulse amplitudes between 0.63v 0-p. and 1.1v 0-p .
DS3101 stratum 3/3e timing card ic 55 of 149 7.11 microprocessor interfaces the DS3101 microprocessor interface can be configured for 8-bit parallel or spi serial operation. during reset, the device determines its interface mode by latching the stat e of the ifsel[2:0] pins into the ifsel field of the ifcr register. table 7-18 shows possible values of ifsel. table 7-18. microprocessor interface modes ifsel[2:0] mode 010 intel bus mode (multiplexed) 011 intel bus mode (nonmultiplexed) 100 motorola mode (nonmultiplexed) 101 spi mode (lsb first) 110 motorola mode (multiplexed) 111 spi mode (msb first) 000, 001 {unused value} 7.11.1 parallel interface modes in the motorola interface modes, th e interface is motorola-style with cs , r/ w , and ds control lines. in the intel modes, the interface is intel-style with cs, rd, and wr control lines. for multiplex ed bus modes, the a[8], ad[7:0], and ale pins are wired to the corresponding pins on the microprocessor, and the falling edge of ale latches the address on a[8] and ad[7:0]. for nonmultiplexed bus mode s, the a[8:0] and ad[7:0] pins are wired to the corresponding pins on the micro, and the falling edge of ale latches the address on a[8:0]. in nonmultiplexed bus modes, ale is typically wired high to make the latch transparent. see section 10.4 for ac timing details. 7.11.2 spi interface mode in the spi modes, the device presents an spi interface on the cs , sclk, sdi, and sdo pins. spi is a widely used master/slave bus protocol that allows a master device and one or more slave devices to communicate over a serial bus. the DS3101 is always a slave device. masters are typically microprocessors, asics, or fpgas. data transfers are always initiated by the master device, whic h also generates the sclk signal. the DS3101 receives serial data on the sdi pin and transmits serial data on the sdo pin. sdo is high impedance except when the DS3101 is transmitting data to the bus master. bit order. when ifcr :ifsel = 101, the register address and all data bytes are transmitted lsb first on both sdi and sdo. when ifsel = 111, the register address and all data bytes are transmitted msb first on both sdi and sdo. the motorola spi convention is msb first. clock polarity and phase. the cpol pin defines the polarity of sclk . when cpol = 0, sclk is normally low and pulses high during bus transactions. when cpol = 1, sclk is normally high and pulses low during bus transactions. the cpha pin sets the phase (active edge) of sclk. when cpha = 0, data is latched in on sdi on the leading edge of the sclk pulse and updated on sdo on t he trailing edge. when cpha = 1, data is latched in on sdi on the trailing edge of the sclk pulse and updated on sdo on the following leading edge. sclk does not have to toggle between access, i.e., when cs is high. see figure 7-8 . device selection. each spi device has its own chip-selec t line. to select the DS3101, pull its cs pin low. control word. after cs is pulled low, the bus master transmits the c ontrol word during the first 16 sclk cycles. in msb-first mode, the control word has the form: r/ w a13 a12 a11 a10 a9 a8 a7 a6 a5 a4 a3 a2 a1 a0 burst where a[13:0] is the register address, r/ w is the data direction bit (1 = read, 0 = write), and burst is the burst bit (1 = burst access, 0 = single-byte access). in lsb-first mo de, the order of the 14 address bits is reversed. in the discussion that follows, a control word with r/ w = 1 is a read control word, while a control word with r/ w = 0 is a write control word. single-byte writes. see figure 7-9 . after cs goes low, the bus master transmit s a write control word with burst = 0 followed by the data byte to be written. the bu s master then terminates the transaction by pulling cs high.
DS3101 stratum 3/3e timing card ic 56 of 149 single-byte reads. see figure 7-9 . after cs goes low, the bus master transmit s a read control word with burst = 0. the DS3101 then responds with the requested data byte . the bus master then terminates the transaction by pulling cs high. burst writes. see figure 7-9 . after cs goes low, the bus master transmits a write control word with burst = 1 followed by the first data byte to be written. the DS3101 receives the first data byte on sdi, writes it to the specified register, increments its inte rnal address register, and prepares to receive the next data byte. if the master continues to transmit, the DS3101 continues to write the data received and increment its address counter. after the address counter reaches 3fffh, it rolls over to address 0000h and continues to increment. burst reads. see figure 7-9 . after cs goes low, the bus master transmits a read control word with burst = 1. the DS3101 then responds with the requested data byte on sdo, increments its addres s counter, and prefetches the next data byte. if the bus master continues to demand data, the DS3101 continues to provide the data on sdo, increment its address counter, and prefetch the following by te. after the address counter reaches 3fffh, it rolls over to address 0000h and continues to increment. early termination of bus transactions. the bus master can terminate spi bus transactions at any time by pulling cs high. in response to early terminations, the DS3101 resets its spi interface logic and waits for the start of the next transaction. if a write transaction is terminat ed prior to the sclk edge that latches the lsb of a data byte, the data byte is not written. design option: wiring sdi and sdo together. because communication between the bus master and the DS3101 is half-duplex, the sdi and sdo pins can be wired to gether externally to reduce wire count. to support this option, the bus master must not drive the sdi/sdo line when the DS3101 is transmitting. ac timing. see table 10-12 and figure 10-6 for ac timing specifications for the spi interface. figure 7-8. spi clock po larity and phase options msb lsb 654321 cs sck sck sck sck sdi/sdo clock edge used for data capture (all modes) cpol = 0, cpha = 0 cpol = 0, cpha = 1 cpol = 1, cpha = 0 cpol = 1, cpha = 1
DS3101 stratum 3/3e timing card ic 57 of 149 figure 7-9. spi bus transactions r/ w register address burst data byte sdi cs sdo single-byte write single-byte read r/ w register address burst data byte r/ w register address burst data byte 1 burst write sdi cs sdo sdi cs sdo 0 (write) 0 (single-byte) 1 (read) 0 (single-byte) 0 (write) 1 (burst) data byte n r/ w register address burst data byte 1 burst read sdi cs 1 (read) 1 (burst) data byte n 7.12 reset logic the device has three reset controls: the rst pin, the rst bit in mcr1 , and the jtag reset pin, jtrst . the rst pin asynchronously resets the entire device , except for the jtag logic. when the rst pin is low, all internal registers are reset to their default values, including those fiel ds that latch their default values from, or based on, the states of input pins (such as ifcr :ifsel[2:0]). the rst pin must be asserted once after power-up. the mcr1 :rst bit resets the entire device (except for the mi croprocessor interface, the jtag logic, and the rst bit itself), but when rst is active, the register fields with pin-programmed defaults do not latch their values from, or based on, the corresponding input pins. instead, these fields are reset to the default values that were latched when the rst pin was last active. maxim/dallas semiconductor recommends holding rst low while the external oscilla tor starts up and stabilizes. some ocxos take 250ms or more to start up and stabilize their output signals to valid logic levels and pulse widths. an incorrect reset condition could result if rst is released before the oscilla tor has started up completely.
DS3101 stratum 3/3e timing card ic 58 of 149 7.13 power-supply considerations due to the dual-power-supply nature of the DS3101, some i/os have parasitic diodes between a 1.8v supply and a 3.3v supply. when ramping power supplies up or down, ca re must be taken to avoid forward-biasing these diodes because it could cause latchup. two me thods are available to prevent this. the first method is to place a schottky diode external to the device between the 1.8v supply and the 3.3v supply to force the 3.3v supply to be less than one parasitic diode drop below the 1.8v supply. the second method is to ramp up the 3.3v supply first and then ramp up the 1.8v supply. 7.14 initialization after power-up or reset, a series of writes must be done to the DS3101 to tune it for optimal performance. this series of writes is called the initialization script. each di e revision of the DS3101 has a different initialization script. download the latest initialization scripts from the DS3101 website, www.maxim-ic.com/DS3101 , or email telecom.support@dalsemi.com .
DS3101 stratum 3/3e timing card ic 59 of 149 8. register descriptions table 8-1. top-level memory map address range functional block 0000?007fh pll register space 0080?01ffh reserved as shown in table 8-1 the DS3101 occupies an address range from 0000h to 01ffh. addresses 0000h to 007fh contain the user-accessible registers shown in table 8-2 . addresses 0080h to 01ffh are reserved and should not be written. in each register, bit 7 is the msb and bit 0 is the lsb. register addresses not listed and bits marked with the symbol ??? are reserved and must be written with 0. writing other values to these registers may put the device in a factory test mode, resulting in undefined operation. bits labeled ?0? or ?1? must be written with that value for proper operation. register fields with underlined names are read-only fields; writes to these fields have no effect. all other fields are read-write. re gister fields are described in detail in the register descriptions that follow table 8-2 . 8.1 status bits the device has two types of status bits. real-time status bits are read-only and indicate the state of a signal at the time it is read. latched status bits are set when a signal changes state (low-to-high, hi gh-to-low, or both, depending on the bit) and cleared when written with a logic 1 value. wr iting a 0 has no effect. when set, some latched status bits can cause an interrupt request on the intreq pin if enabled to do so by corresponding interrupt enable bits. 8.2 configuration fields configuration fields are read-write. du ring reset, each configuration field reverts to the default value shown in the register definition. configuration register bits marked ??? are reserved and must be written with 0. 8.3 multiregister fields multiregister fields?such as freq[18:0] in registers freq1 , freq2 , and freq3 ?must be handled carefully to ensure that the bytes of the field remain consistent. a write access to a multiregister field is accomplished by writing all the registers of the field in any order, with no other accesses to the device in between. if the write sequence is interrupted by another access, none of the bytes are written and the msr4 :mraa bit is set to indicate the write was aborted. a read access from a multiregister field is accomplished by reading the registers of the field in any order, with no other accesses to the device in between. when one register of a multiregister field is read, the other register(s) in the field are froz en until after they are all read. if the read sequence is interrupted by another access, the registers of the multibyte field are unfrozen and the msr4 :mraa bit is set to indicate the read was aborted. for best results, interrupt servicing should be di sabled in the microprocessor before a multiregister access and then enabled again after the access is complete. the multiregister fields are: field registers addresses type freq[18:0] freq1 , freq2 , freq3 07, 0c, 0d read-only mclkfreq[15:0] mclk1 , mclk2 3c, 3d read/write hofreq[18:0] hocr1 , hocr2 , hocr3 * 3e, 3f, 40 read/write hardlim[9:0] dlimit1 , dlimit2 41, 42 read/write divn[14:0] divn1 , divn2 46, 47 read/write offset[15:0] offset1 , offset2 70, 71 read/write phase[15:0] phase1 , phase2 77, 78 read-only * hocr3 is a special case because its upper 5 bits are not part of a mu ltiregister field, but its lower 3 bits are part of the hofreq[ 18:0] multiregister field. writes to hocr3 immediately update the upper 5 bits wit hout any requirement to also write hocr1 and hocr2 . the lower 3 bits of hocr3 (hofreq[18:16]), however, can only be written as part of a pr oper write sequence for a multiregister field, as described above. a write to hocr3 continugous with writes to hocr1 and hocr2 can simultaneously write the upper 5 bits immediately and start/continue/complete a multiregister write of hofreq[18:0].
DS3101 stratum 3/3e timing card ic 60 of 149 8.4 register definitions table 8-2. register map note: register names are hyperlinks to register definitions. underlined fields are read-only. addr register bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 00h id1 id[7:0] 01 id2 id[15:8] 02 rev rev[7:0] 03 test1 palarm d180 ? ra 0 8kpol 0 0 05 msr1 ic8 ic7 ic6 ic5 ic4 ic3 ic2 ic1 06 msr2 state srfail ic14 ic13 ic12 ic11 ic10 ic9 07 freq3 ? ? ? ? ? freq[18:16] 08 msr3 fsmon t4lock phmon t4noin ami2 los2 ami1 los1 09 opstate fsmon t4lock t0soft t4soft ? t0state[2:0] 0a ptab1 ref1[3:0] selref[3:0] 0b ptab2 ref3[3:0] ref2[3:0] 0c freq1 freq[7:0] 0d freq2 freq[15:8] 0e valsr1 ic8 ic7 ic6 ic5 ic4 ic3 ic2 ic1 0f valsr2 fhordy shordy ic14 ic13 ic12 ic11 ic10 ic9 10 isr1 soft2 hard2 act2 lock2 soft1 hard1 act1 lock1 11 isr2 soft4 hard4 act4 lock4 soft3 hard3 act3 lock3 12 isr3 soft6 hard6 act6 lock6 soft5 hard5 act5 lock5 13 isr4 soft8 hard8 act8 lock8 soft7 hard7 act7 lock7 14 isr5 soft10 hard10 act10 lock10 soft9 hard9 act9 lock9 15 isr6 soft12 hard12 act12 lock12 soft11 hard11 act11 lock11 16 isr7 soft14 hard14 act14 lock14 soft13 hard13 act13 lock13 17 msr4 fhordy shordy mraa ? ic2no4 ic1no4 ic2no8 ic1no8 18 ipr1 pri2[3:0] pri1[3:0] 19 ipr2 pri4[3:0] pri3[3:0] 1a ipr3 pri6[3:0] pri5[3:0] 1b ipr4 pri8[3:0] pri7[3:0] 1c ipr5 pri10[3:0] pri9[3:0] 1d ipr6 pri12[3:0] pri11[3:0] 1e ipr7 pri14[3:0] pri13[3:0] 20 icr1 divn lock8k bucket[1:0] freq[3:0] 21 icr2 divn lock8k bucket[1:0] freq[3:0] 22 icr3 divn lock8k bucket[1:0] freq[3:0] 23 icr4 divn lock8k bucket[1:0] freq[3:0] 24 icr5 divn lock8k bucket[1:0] freq[3:0] 25 icr6 divn lock8k bucket[1:0] freq[3:0] 26 icr7 divn lock8k bucket[1:0] freq[3:0] 27 icr8 divn lock8k bucket[1:0] freq[3:0] 28 icr9 divn lock8k bucket[1:0] freq[3:0] 29 icr10 divn lock8k bucket[1:0] freq[3:0] 2a icr11 divn lock8k bucket[1:0] freq[3:0] 2b icr12 divn lock8k bucket[1:0] freq[3:0] 2c icr13 divn lock8k bucket[1:0] freq[3:0] 2d icr14 divn lock8k bucket[1:0] freq[3:0] 30 valcr1 ic8 ic7 ic6 ic5 ic4 ic3 ic2 ic1 31 valcr2 ? ? ic14 ic13 ic12 ic11 ic10 ic9 32 mcr1 rst ? ? ? ? t0state[2:0] 33 mcr2 ? ? ? ? t0force[3:0]
DS3101 stratum 3/3e timing card ic 61 of 149 addr register bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 34 mcr3 aefsen lkato xoedge manho efsen sonsdh mastslv revert 35 mcr4 lkt4t0 t4dfb ? oc89 t4force[3:0] 36 mcr5 ccedge biterr ami los ic2sf ic1sf ic6sf ic5sf 37 ifsr ? ? ? ? ? ifsel[2:0] 38 mcr6 dig2af dig2ss dig1ss ? ? ? ? ? 39 mcr7 dig2f[1:0] dig1f[1:0] ? ? ? ? 3a mcr8 ? ? oc8400 oc8no8 oc7sf oc6sf 3b mcr9 autobw ? ? ? limint pfd180 ? ? 3c mclk1 mclkfreq[7:0] 3d mclk2 mclkfreq[15:8] 3e hocr1 hofreq[7:0] 3f hocr2 hofreq[15:8] 40 hocr3 avg fast rdavg miniho[1:0] hofreq[18:16] 41 dlimit1 hardlim[7:0] 42 dlimit2 ? ? ? ? ? ? hardlim[9:8] 43 ier1 ic8 ic7 ic6 ic5 ic4 ic3 ic2 ic1 44 ier2 state srfail ic14 ic13 ic12 ic11 ic10 ic9 45 ier3 fsmon t4lock phmon t4noin ami2 los2 ami1 los1 46 divn1 divn[7:0] 47 divn2 ? divn[14:8] 48 mcr10 fmonclk srfpin ufsw extsw pbofrz pboen soften harden 49 ilimit soft[3:0] hard[3:0] 4a srlimit soft[3:0] hard[3:0] 4b mcr11 ? ? ? t4t0 fmeasin[3:0] 4c fmeas fmeas[7:0] 4d dlimit3 fllol softlim[6:0] 4e ier4 fhordy shordy ? ? ic2no4 ic1no4 ic2no8 ic1no8 50 lb0u lb0u[7:0] 51 lb0l lb0l[7:0] 52 lb0s lb0s[7:0] 53 lb0d ? ? ? ? ? ? lb0d[1:0] 54 lb1u lb1u[7:0] 55 lb1l lb1l[7:0] 56 lb1s lb1s[7:0] 57 lb1d ? ? ? ? ? ? lb1d[1:0] 58 lb2u lb2u[7:0] 59 lb2l lb2l[7:0] 5a lb2s lb2s[7:0] 5b lb2d ? ? ? ? ? ? lb2d[1:0] 5c lb3u lb3u[7:0] 5d lb3l lb3l[7:0] 5e lb3s lb3s[7:0] 5f lb3d ? ? ? ? ? ? lb3d[1:0] 60 ocr1 ofreq2[3:0] ofreq1[3:0] 61 ocr2 ofreq4[3:0] ofreq3[3:0] 62 ocr3 ofreq6[3:0] ofreq5[3:0] 63 ocr4 oc11en oc10en oc9en oc8en ofreq7[3:0] 64 t4cr1 ? asquel oc8duty oc9son t4freq[3:0] 65 t0cr1 t4mt0 t4apt0 t0ft4[2:0] t0freq[2:0] 66 t4bw ? ? ? ? ? ? t4bw[1:0] 67 t0lbw ? ? ? t0lbw[4:0] 69 t0abw ? ? ? t0abw[4:0] 6a t4cr2 ? pd2ga8k[2:0] ? damp[2:0] 6b t0cr2 ? pd2ga8k[2:0] ? damp[2:0] 6c t4cr3 pd2en pd2ga[2:0] ? pd2gd[2:0]
DS3101 stratum 3/3e timing card ic 62 of 149 addr register bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 6d t0cr3 pd2en pd2ga[2:0] ? pd2gd[2:0] 6e gpcr gpio4d gpio3d gpio2d gpio1d gpio4o gpio3o gpio2o gpio1o 6f gpsr ? ? ? ? gpio4 gpio3 gpio2 gpio1 70 offset1 offset[7:0] 71 offset2 offset[15:8] 72 pboff ? ? pboff[5:0] 73 phlim1 flen nalol 1 ? ? finelim[2:0] 74 phlim2 clen mcpden usemcpd ? coarselim[3:0] 76 phmon nw ? pmen pmpben pmlim[3:0] 77 phase1 phase[7:0] 78 phase2 phase[15:8] 79 phlkto phlktom[1:0] phlkto[5:0] 7a fscr1 2k8ksrc ? ? ? 8kinv 8kpul 2kinv 2kpul 7b fscr2 indep ocn ? ? ? ? phase[1:0] 7c fscr3 recal monlim[2:0] source[3:0] 7d intcr ? ? ? ? ? gpo od pol 7e prot prot[7:0] 7f ifcr ? ? ? ? ? ifsel[2:0] register map color coding device identification and protection local oscillator and master clock configuration input clock configuration input clock monitoring input clock selection dpll configuration dpll state output clock configuration sync2k configuration microprocessor interf ace configuration unused register addresses 04h, 1fh, 2eh, 2fh, 4fh, 68h, 75h
DS3101 stratum 3/3e timing card ic 63 of 149 register name: id1 register description: device identification register, lsb register address: 00h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name id[7:0] default 0 0 0 1 1 1 0 1 bits 7 to 0: device id (id[7:0]). id[15:0] = 0c1dh = 3101 decimal. register name: id2 register description: device identification register, msb register address: 01h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name id[15:8] default 0 0 0 0 1 1 0 0 bits 7 to 0: device id (id[15:8]). see the id1 register description. register name: rev register description: device revision register register address: 02h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name rev[7:0] default 0 0 0 0 0 0 0 0 bits 7 to 0: device revision (rev[7:0]). contact the factory to interpret this value and determine the latest revision.
DS3101 stratum 3/3e timing card ic 64 of 149 register name: test1 register description: test register 1 (not normally used) register address: 03h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name palarm d180 ? ra 0 8kpol 0 0 default 0 0 0 1 0 1 0 0 bit 7: phase alarm (palarm). this real-time status bit indicate s the state of t0 dpll phase lock. 0 = t0 phase-locked to input reference 1 = t0 loss of phase lock bit 6: disable 180 (d180). when locking to a new reference, the t0 dpll first tries nearest-edge locking ( 180 ) for the first two seconds. if unsuccessful it then tries full phase/frequency locking ( 360 ). disabling the nearest- edge locking can reduce lock time by up to two seco nds but may cause an unnecessary phase shift (up to 360 ) when the new reference is close in frequency /phase to the old reference. see section 7.7.5 . 0 = normal operation: try nearest-edge locking then phase/frequency locking 1 = phase/frequency locking only bit 4: resync analog dividers (ra). when this bit is set the t0 apll output dividers are always synchronized to ensure that low-frequency outputs are in sync with the higher-frequency clock from the t0 dpll. 0 = not synchronized 1 = always synchronized bit 3: leave set to zero (test control). bit 2: 8khz edge polarity (8kpol). specifies the input clock edge to lock to on the selected reference when it is configured for lock8k mode. see section 7.4.2 . 0 = falling edge 1 = rising edge bit 1: leave set to zero (test control). bit 0: leave set to zero (test control).
DS3101 stratum 3/3e timing card ic 65 of 149 register name: msr1 register description: master status register 1 register address: 05h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ic8 ic7 ic6 ic5 ic4 ic3 ic2 ic1 default 1 1 1 1 1 1 1 1 bits 7 to 0: input clock status change (ic8 to ic1). each of these latched status bits is set to 1 when the corresponding valsr1 status bit changes state (set or clea red). if soft frequency limit alarms are enabled ( mcr10 :soften = 1), then each of these latched status bits is also set to 1 when the corresponding soft bit in the isr registers changes state (set or cleared). each bit is cleared when written with a 1 and not set again until either the valsr1 bit or the soft bit changes state again. when one of these latched status bits is set it can cause an interrupt request on the intreq pin if the corresponding interrupt enable bit is set in the ier1 register. see section 7.5 for input clock validation/invalidation criteria. register name: msr2 register description: master status register 2 register address: 06h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name state srfail ic14 ic13 ic12 ic11 ic10 ic9 default 0 0 1 1 1 1 1 1 bit 7: t0 dpll state change (state). this latched status bit is set to 1 wh en the operating state of the t0 dpll changes. state is cleared when written with a 1 and not set again until the operating state changes again. when state is set it can cause an interrupt request on the in treq pin if the state interrupt enable bit is set in the ier2 register. the current operating state ca n be read from the t0state field of the opstate register. see section 7.7.1 . bit 6: selected reference failed (srfail). this latched status bit is set to 1 when the selected reference to the t0 dpll fails (i.e., no clock edges in two ui). srfail is cleared when written with a 1. when srfail is set it can cause an interrupt request on the intreq pin if the srfail interrupt enable bit is set in the ier2 register. srfail is not set in free-run mode or holdover mode. see section 7.5.3 . bits 5 to 0: input clock status change (ic14 to ic9). each of these latched status bits is set to 1 when the corresponding valsr status bit changes state (set or cleared). if soft frequency limit alarms are enabled ( mcr10 :soften = 1), then each of these latched status bits is also set to 1 when the corresponding soft bit in the isr registers changes state (set or cleared). each bit is cleared when written with a 1 and not set again until either the valsr2 bit or the soft bit changes state again. when one of these latched status bits is set it can cause an interrupt request on the intreq pin if the corresponding interrupt enable bit is set in the ier2 register. see section 7.5 for input clock validation/invalidation criteria. register name: freq3 register description: frequency register 3 register address: 07h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? ? ? ? ? freq[18:16] default 0 0 0 0 0 0 0 0 bits 2 to 0: current dpll frequency (freq[18:16]). see the freq1 register description.
DS3101 stratum 3/3e timing card ic 66 of 149 register name: msr3 register description: master status register 3 register address: 08h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name fsmon t4lock phmon t4noin ami2 los2 ami1 los1 default 0 1 0 1 0 0 0 0 bit 7: frame sync input monitor alarm (fsmon). this latched status bit is set to 1 when opstate :fsmon transitions from 0 to 1. fsmon is cleared when written wi th a 1. when fsmon is set it can cause an interrupt request on the intreq pin if the fsmon interrupt enable bit is set in the ier3 register. see section 7.9.3 . bit 6: t4 dpll lock status change (t4lock). this latched status bit is set to 1 when the lock status of the t4 dpll ( opstate :t4lock) changes (becomes locked when previ ously unlocked or becomes unlocked when previously locked). t4lock is cleared when written with a 1 and not set again until the t4 lock status changes again. when t4lock is set it can cause an interrupt reque st on the intreq pin if the t4lock interrupt enable bit is set in the ier3 register. see section 7.7.6 . bit 5: phase monitor alarm (phmon). this latched status bit is set to 1 when the phase monitor alarm limit has been exceeded (pmlim field of the phmon register). phmon is cleared when written with a 1 and not set again until the threshold is exceeded again. when phmon is set it can cause an interrupt request on the intreq pin if the phmon interrupt enable bit is set in the ier3 register. see section 7.7.7 . bit 4: t4 no valid inputs alarm (t4noin). this latched status bit is set to 1 when the t4 dpll has no valid inputs available. t4noin is cleared when written with a 1 unless the t4 dpll still has no valid inputs available. when t4noin is set it can cause an interrupt request on the intreq pin if the t4noin interrupt enable bit is set in the ier3 register. see section 7.5 . bit 3: ami violation on ic2 (ami2). this latched status bit is set to 1 when a deviation from the expected pattern of seven ones followe d by a bpv occurs on the ic2 input in each of two consecutive 8- bit periods. however, if the composite clock receiver c an detect the presence of the 400 hz com ponent required by g.703 appendix ii.1 option b), then the missing bpvs that indicate the 400 hz component are not considered ami violations. ami2 is cleared when written with a 1 and not set again until another ami violation occurs. when ami2 is set it can cause an interrupt request on the intreq pin if the ami2 interrupt enable bit is set in the ier3 register. this status bit is only enabled when ic2 is configured as a composite clock receiver ( mcr5 :ic2sf = 0). see section 7.10.1 . bit 2: los error on ic2 (los2). this latched status bit is set to 1 when no pulses are detected on the ic2 input in a 32 s period (i.e., after two missing pulses). los2 is clea red when written with a 1 and is not set again until ic2 transitions from valid signal to loss-of-signal again. wh en los2 is set it can cause an interrupt request on the intreq pin if the los2 interrupt enable bit is set in the ier3 register. this status bit is only enabled when ic2 is configured as a composite clock receiver ( mcr5 :ic2sf = 0). see section 7.10.1 . bit 1: ami violation on ic1 (ami1). this latched status bit is set to 1 when a deviation from the expected pattern of seven ones followe d by a bpv occurs on the ic1 input in each of two consecutive 8- bit periods. however, if the composite clock receiver can detect the presence of t he 400hz component required by g.703 appendix ii.1 option b), then the missing bpvs that indicate the 400hz component are not considered ami violations. ami1 is cleared when written with a 1 and not set again until another ami violation occurs. when ami1 is set it can cause an interrupt request on the intreq pin if the ami1 interrupt enable bit is set in the ier3 register. this status bit is only enabled when ic1 is configured as a composite clock receiver ( mcr5 :ic1sf = 0). see section 7.10.1 . bit 0: los error on ic1 (los1). this latched status bit is set to 1 when no pulses are detected on the ic1 input in a 32 s period (i.e., after two missing pulses). los1 is clear ed when written with a 1 and is not set again until ic1 transitions from valid signal to loss-of-signal again. wh en los1 is set it can cause an interrupt request on the intreq pin if the los1 interrupt enable bit is set in the ier3 register. this status bit is only enabled when ic1 is configured as a composite clock receiver ( mcr5 :ic1sf = 0). see section 7.10.1 .
DS3101 stratum 3/3e timing card ic 67 of 149 register name: opstate register description: operating state register register address: 09h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name fsmon t4lock t0soft t4soft ? t0state[2:0] default 0 1 0 0 0 0 0 1 bit 7: frame sync input monitor alarm (fsmon). this real-time status bit indicates the current status of the frame sync input monitor. see section 7.9.3 . 0 = no alarm 1 = alarm bit 6: t4 dpll lock status (t4lock). this real-time status bit indicates th e current phase lock status of the t4 dpll. see sections 7.5.3 and 7.7.6 . 0 = not locked to selected reference 1 = locked to selected reference bit 5: t0 dpll frequency soft alarm (t0soft). this real-time status bit indicate s whether or not the t0 dpll is tracking its reference within the soft alarm lim its specified in the soft[6:0] field of the dlimit3 register. see section 7.7.6 . 0 = no alarm; frequency is within the soft alarm limits 1 = soft alarm; frequency is outside the soft alarm limits bit 4: t4 dpll frequency soft alarm (t4soft). this real-time status bit indicate s whether or not the t4 dpll is tracking its reference within the soft alarm lim its specified in the soft[6:0] field of the dlimit3 register. see section 7.7.6 . 0 = no alarm; frequency is within the soft alarm limits 1 = soft alarm; frequency is outside the soft alarm limits bits 2 to 0: t0 dpll operating state (t0state[2:0]). this real-time status field indi cates the current state of the t0 dpll state machine. values not listed below co rrespond to invalid (unused) states. see section 7.7.1 . 001 = free-run 010 = holdover 100 = locked 101 = prelocked 2 110 = prelocked 111 = loss-of-lock
DS3101 stratum 3/3e timing card ic 68 of 149 register name: ptab1 register description: priority table register 1 register address: 0ah bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ref1[3:0] selref[3:0] default 0 0 0 0 0 0 0 0 bits 7 to 4: highest priority valid reference (ref1[3:0]). this real-time status field indicates the highest-priority valid input reference. when t4t0 = 0 in the mcr11 register, this field indicates the highest priority reference for the t0 dpll. when t4t0 = 1, it indicates the highest priority reference for the t4 dpll. note that an input reference cannot be indicated in this field if it has been marked invalid in the valcr1 or valcr2 register. when the t0 dpll is in non-reve rtive mode (revert = 0 in the mcr3 register) this field may not have the same value as the selref[3:0] field. see section 7.6.2 . 0000 = no valid input reference available 0001 = input ic1 0010 = input ic2 0011 = input ic3 0100 = input ic4 0101 = input ic5 0110 = input ic6 0111 = input ic7 1000 = input ic8 1001 = input ic9 1010 = input ic10 1011 = input ic11 1100 = input ic12 1101 = input ic13 1110 = input ic14 1111 = {unused value} bits 3 to 0: selected reference (selref[3:0]). this real-time status field indicates the current selected reference. when t4t0 = 0 in the mcr11 register, this field indicates the selected reference for the t0 dpll. when t4t0 = 1, it indicates the selected reference for the t4 dpll. note that an input clock cannot be indicated in this field if it has been marked invalid in the valcr1 or valcr2 register. when the t0 dpll is in nonrevertive mode (revert = 0 in the mcr3 register) this field may not have the same value as the ref1[3:0] field. see section 7.6.2 . 0000 = no source currently selected 0001 = input ic1 0010 = input ic2 0011 = input ic3 0100 = input ic4 0101 = input ic5 0110 = input ic6 0111 = input ic7 1000 = input ic8 1001 = input ic9 1010 = input ic10 1011 = input ic11 1100 = input ic12 1101 = input ic13 1110 = input ic14 1111 = {unused value}
DS3101 stratum 3/3e timing card ic 69 of 149 register name: ptab2 register description: priority table register 2 register address: 0bh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ref3[3:0] ref2[3:0] default 0 0 0 0 0 0 0 0 bits 7 to 4: third highest priority valid reference (ref3[3:0]). this real-time status field indicates the third highest priority validated input reference. when t4t0 = 0 in the mcr11 register, this field indicates the third highest priority reference for the t0 dpll. when t4t0 = 1, it indicates the third highest reference for the t4 dpll. note that an input reference cannot be indicated in this field if it has been marked invalid in the valcr1 or valcr2 register. see section 7.6.2 . 0000 = less than three valid sources available 0001 = input ic1 0010 = input ic2 0011 = input ic3 0100 = input ic4 0101 = input ic5 0110 = input ic6 0111 = input ic7 1000 = input ic8 1001 = input ic9 1010 = input ic10 1011 = input ic11 1100 = input ic12 1101 = input ic13 1110 = input ic14 1111 = {unused value} bits 3 to 0: second highest priority valid reference (ref2[3:0]). this real-time status field indicates the second highest priority validated input reference. when t4t0 = 0 in the mcr11 register, this field indicates the second highest priority reference for the t0 dpll. when t4 t0 = 1, it indicates the second highest reference for the t4 dpll. note that an input reference cannot be indicated in this field if it has been marked invalid in the valcr1 or valcr2 register. see section 7.6.2 . 0000 = less than two valid sources available 0001 = input ic1 0010 = input ic2 0011 = input ic3 0100 = input ic4 0101 = input ic5 0110 = input ic6 0111 = input ic7 1000 = input ic8 1001 = input ic9 1010 = input ic10 1011 = input ic11 1100 = input ic12 1101 = input ic13 1110 = input ic14 1111 = {unused value}
DS3101 stratum 3/3e timing card ic 70 of 149 register name: freq1 register description: frequency register 1 register address: 0ch bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name freq[7:0] default 0 0 0 0 0 0 0 0 the freq1, freq2, and freq3 registers must be read consecutively. see section 8.3 . bits 7 to 0: current dpll frequency (freq[7:0]). the full 19-bit freq[18:0] field spans this register, freq2 and freq3. freq is a two?s-complement signed integer that expresses the current frequency as an offset with respect to the master clock frequency (see section 7.3 ). when t4t0 = 0 in the mcr11 register, freq indicates the current frequency offset of the t0 dpll. when t4t0 = 1, freq indicate s the current frequency offset of the t4 path. because the value in this register field is der ived from the dpll integral path, it can be considered an average frequency with a rate of change inversely proportional to the dpll bandwidth. if limint = 1 in the mcr9 register, the value of freq freezes when the dpll re aches its minimum or maximum frequency. the frequency offset in ppm is equal to freq[18:0] x 0.0003068. see section 7.7.1.6 . application note: frequency measurements are relative, i.e., they measure the frequency of the selected reference with respect to the local oscillator. as such, when a frequenc y difference exists, it is difficult to distinguish whether the selected reference is off frequency or the local o scillator is off frequency. in systems with timing card redundancy, the use of two timing cards, master and slave, can address this difficulty. both master and slave have separate local oscillators, and each measures the selected reference. these two measurements provide the necessary information to distinguish which reference is off frequency, if we make the simple assumption that at most one reference has a significant frequency deviation at any given time (i.e., a single point of failure). if both master and slave indicate a significant frequency offset, then the selected reference must be off frequency. if the master indicates a frequency offset but the slave does no t, then the master?s local oscillator must be off frequency. likewise, if the slave indicates a frequency offset but the master does not, then slave?s local oscillator must be off frequency. register name: freq2 register description: frequency register 2 register address: 0dh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name freq[15:8] default 0 0 0 0 0 0 0 0 bits 7 to 0: current dpll frequency (freq[15:8]). see the freq1 register description.
DS3101 stratum 3/3e timing card ic 71 of 149 register name: valsr1 register description: input clock valid status register 1 register address: 0eh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ic8 ic7 ic6 ic5 ic4 ic3 ic2 ic1 default 0 0 0 0 0 0 0 0 bits 7 to 0: input clock valid status (ic8 to ic1). each of these real-time status bits is set to 1 when the corresponding input clock is valid. an input is valid if it has no active alarms (hard = 0, act = 0, lock = 0 in the corresponding isr register). see also the msr1 register and section 7.5 . 0 = invalid 1 = valid register name: valsr2 register description: input clock valid status register 2 register address: 0fh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name fhordy shordy ic14 ic13 ic12 ic11 ic10 ic9 default 0 0 0 0 0 0 0 0 bit 7: fast holdover frequency ready (fhordy). this real-time status bit is set to 1 when the t0 dpll has a holdover value that has been averaged over the 8-minute holdover averaging period. see the related latched status bit in msr4 and section 7.7.1.6 . bit 6: slow holdover frequency ready (shordy). this real-time status bit is set to 1 when the t0 dpll has a holdover value that has been averaged over the 110-minut e holdover averaging period. see the related latched status bit in msr4 and section 7.7.1.6 . bits 5 to 0: input clock valid status (ic14 to ic9). these bits have the same behavior as the bits in valsr1 but for the ic9 through ic14 input clocks.
DS3101 stratum 3/3e timing card ic 72 of 149 register name: isr1 register description: input status register 1 register address: 10h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name soft2 hard2 act2 lock2 soft1 hard1 act1 lock1 default 0 1 1 0 0 1 1 0 bit 7: soft frequency limit alarm for input clock 2 (soft2). this real-time status bit indicates a soft frequency limit alarm for input clock 2. if ic2 is the selected refe rence then soft2 is set to 1 when the frequency of ic2 is greater than or equal to the soft limit set in the srlimit register. if ic2 is not the selected reference then soft2 is set to 1 when the frequency of ic2 is greater than or equal to the soft limit set in the ilimit register. soft alarms are disabled by default but can be enabled by setting soften = 1 in the mcr10 register. a soft alarm does not invalidate an input clock. see section 7.5.1 . bit 6: hard frequency limit alarm for input clock 2 (hard2). this real-time status bit indicates a hard frequency limit alarm for input clock 2. if ic2 is the sele cted reference then hard2 is set to 1 when the frequency of ic2 is greater than or equal to the hard limit set in the srlimit register. if ic2 is not the selected reference then hard2 is set to 1 when the frequency of ic2 is greater than or equal to the hard limit set in the ilimit register. hard alarms are enabled by default but can be disabled by setting harden = 0 in the mcr10 register. a hard alarm clears the ic2 status bit in the valsr1 register, invalidating t he ic2 clock. see section 7.5.1 . bit 5: activity alarm for input clock 2 (act2). this real-time status bit is set to 1 when the leaky bucket accumulator for ic2 reaches the alarm threshold specified in the lbxu register (where ?x? in ?lbxu? is specified in the bucket field of icr2 ). an activity alarm clears the ic2 status bit in the valsr1 register, invalidating the ic2 clock. see section 7.5.2 . bit 4: phase lock alarm for input clock 2 (lock2). this status bit is set to 1 if ic2 is the selected reference and the t0 dpll cannot phase lock to ic2 within the duration specified in the phlkto register (default = 100 seconds). a phase lock alarm clears the ic2 status bit in valsr1 , invalidating the ic2 clock. if lkato = 1 in mcr3 then lock2 is automatically cleared after a timeout period of 128 seconds. lock2 is a read/write bit. system software can clear lock2 by writing 0 to it, but writing 1 is ignored. see section 7.7.1 . bit 3: soft frequency limit alarm for input clock 1 (soft1). this bit has the same behavior as the soft2 bit but for the ic1 input clock. bit 2: hard frequency limit alarm for input clock 1 (hard1). this bit has the same behavior as the hard2 bit but for the ic1 input clock. bit 1: activity alarm for input clock 1 (act1). this bit has the same behavior as the act2 bit but for the ic1 input clock. bit 0: phase lock alarm for input clock 1 (lock1). this bit has the same behavior as the lock2 bit but for the ic1 input clock.
DS3101 stratum 3/3e timing card ic 73 of 149 register name: isr2, isr3, isr4, isr5, isr6, isr7 register description: input status register 2, 3, 4, 5, 6, 7 register address: 11h, 12h, 13h, 14h, 15h, 16h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name softn hardn actn lockn softm hardm actm lockm default 0 1 1 0 0 1 1 0 these registers have the same behavior as isr1 but for the other input clocks, as follows: input clocks register ic4 and ic3 isr2 ic6 and ic5 isr3 ic8 and ic7 isr4 ic10 and ic9 isr5 ic12 and ic11 isr6 ic14 and ic13 isr7
DS3101 stratum 3/3e timing card ic 74 of 149 register name: msr4 register description: master status register 4 register address: 17h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name fhordy shordy mraa ? ic2no4 ic1no4 ic2no8 ic1no8 default 0 0 0 0 0 0 0 0 bit 7: fast holdover frequency ready (fhordy). this latched status bit is set to 1 when the t0 dpll has a holdover value that has been averaged over the 8-minute holdover averaging period. fhordy is cleared when written with a 1. when fhordy is set it can cause an interrupt request on the intreq pin if the fhordy interrupt enable bit is set in the ier4 register. see section 7.7.1.6 . bit 6: slow holdover frequency ready (shordy). this latched status bit is set to 1 when the t0 dpll has a holdover value that has been averaged over the 110-minute holdover averagin g period. shordy is cleared when written with a 1. when shordy is set it can cause an interrupt request on the intreq pin if the shordy interrupt enable bit is set in the ier4 register. see section 7.7.1.6 . bit 5: multiregister access aborted (mraa). this latched status bit is set to 1 when a multibyte access (read or write) is interrupted by another access to the device. mraa is cleared when written with a 1. mraa cannot cause an interrupt to occur. see section 8.3 . bit 3: input clock 2 has no 400hz component (ic2no4). this latched status bit is set to 1 when the missing bpvs that indicate the 400hz component cannot be found in a 5ms period (two 400hz cy cles). ic2no4 is cleared when written with a 1 unless the 400 hz component is still not present. when ic2no4 is set it can cause an interrupt request on the intreq pin if the ic2no4 interrupt enable bit is set in the ier4 register. this status bit is only enabled when ic2 is configured as a composite clock receiver ( mcr5 :ic2sf = 0). see section 7.10.1 . bit 2: input clock 1 has no 400hz component (ic1no4). this latched status bit is set to 1 when the missing bpvs that indicate the 400hz component cannot be found in a 5ms period (two 400hz cy cles). ic1no4 is cleared when written with a 1 unless the 400 hz component is still not present. when ic1no4 is set it can cause an interrupt request on the intreq pin if the ic1no4 interrupt enable bit is set in the ier4 register. this status bit is only enabled when ic1 is configured as a composite clock receiver ( mcr5 :ic1sf = 0). see section 7.10.1 . bit 1: input clock 2 has no 8khz component (ic2no8). this latched status bit is set to 1 when the bpvs that indicate the 8khz component cannot be found in the incoming signal in a 500 s period (four 8khz cycles). ic2no8 is cleared when written with a 1 unless the 8khz component is still not present. when ic2no8 is set it can cause an interrupt request on the intreq pin if the ic2no8 interrupt enable bit is set in the ier4 register. this status bit is only enabled when ic2 is configured as a composite clock receiver ( mcr5 :ic2sf = 0). see section 7.10.1 . bit 0: input clock 1 has no 8khz component (ic1no8). this latched status bit is set to 1 when the bpvs that indicate the 8khz component cannot be found in the incoming signal in a 500 s period (four 8khz cycles). ic1no8 is cleared when written with a 1 unless the 8khz component is still not present. when ic1no8 is set it can cause an interrupt request on the intreq pin if t he ic1no8 interrupt enable bit is set in the ier4 register. this bit register is only enabled when ic1 is conf igured as a composite clock receiver ( mcr5 :ic1sf = 0). see section 7.10.1 .
DS3101 stratum 3/3e timing card ic 75 of 149 register name: ipr1 register description: input priority register 1 register address: 18h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name pri2[3:0] pri1[3:0] default (t0) 0 0 1 1 0 0 1 0 default (t4) 0 0 0 0 0 0 0 0 bits 7 to 4: priority for input clock 2 (pri2). priority 0001 is highest; priority 1111 is lowest. when mcr11 :t4t0 = 0, pri2 configures ic2?s priority for the t0 dpll. when t4t0 = 1, pri2 configures ic2?s priority for the t4 path. see section 7.6.1 . 0000 = ic2 unavailable for selection. 0001?1111= ic2 relative priority bits 3 to 0: priority for input clock 1 (pri1). priority 0001 is highest; priority 1111 is lowest. when mcr11 :t4t0 = 0, pri1 configures ic1?s priority for the t0 dpll. when t4t0 = 1, pri1 configures ic1?s priority for the t4 path. see section 7.6.1 . 0000 = ic1 unavailable for selection. 0001?1111 = ic1 relative priority register name: ipr2, ipr3, ipr4, ipr5, ipr6, ipr7 register description: input priority register 2, 3, 4, 5, 6, 7 register address: 19h, 1ah, 1bh, 1ch, 1dh, 1eh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name prin[3:0] prim[3:0] default see table these registers have the same behavior as ipr1 but for the other input clocks, as follows: input clocks register default (t0) default (t4) ic4 and ic3 ipr2 0101 0100 0000 0000 ic6 and ic5 ipr3 0111 0110 0111 0110 ic8 and ic7 ipr4 1001 1000 1001 1000 ic10 and ic9 ipr5 1011 1010 1011 1010 ic12 and ic11 ipr6 1101 1100 or 1101 0001* 0000 0000 ic14 and ic13 ipr7 1111 1110 0000 0000 * in register ipr6, for the t0 path, if the mastslv pin is high (master mode) when rst = 0 then the default priority of input ic11 (pri11) is 12. if the mastslv pin is low (slave mode) when rst = 0, then the default priority of ic11 is 1. when the device is in slave mode values written to pri11[3:0] are latched, but the value read is always 0001 to indica te that input 11 is forced to have priority 1. see section 7.9.1 .
DS3101 stratum 3/3e timing card ic 76 of 149 register name: icr1, icr2, icr3, icr4, icr5, icr6, icr7 , icr8, icr9, icr10, icr11, icr12, icr13, icr14 register description: input configuration register 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 register address: 20h, 21h, 22h, 23h, 24h, 25h, 26h, 27h, 28h, 29h, 2ah, 2bh, 2ch, 2dh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name divn lock8k bucket[1:0] freq[3:0] default 0 0 0 0 see below these registers are identical in function. icrx is the control register for input clock icx. bit 7: divn mode (divn). when divn is set to 1, the input clock is divided down by a programmable pre-divider. the resulting output clock is then passed to the dpll and frequency monitor. all input clocks for which divn = 1 are divided by the factor specified in divn1 and divn2 . when divn = 1 in an icr register, the freq field of that register must be set to 8khz. see section 7.4.2.3 . 0 = disabled 1 = enabled bit 6: lock8k mode (lock8k). when lock8k is set to 1, the input clock is divided down by a preset predivider. the resulting output clock, which is always 8khz, is then passed to the dpll. lock8k is ignored when divn = 1. lock8k is also ignor ed when divn = 0 and freq[3:0] = 1001 (2khz) or 1010 (4khz). see section 7.4.2.2 . 0 = disabled 1 = enabled bits 5 to 4: leaky bucket configuration (bucket[1:0]). each input clock has leaky bucket accumulator logic in its activity monitor. the lbxy registers at addresses 50h to 5fh specify four different leaky bucket configurations. any of the four configurations can be s pecified for the input clock. see section 7.5.2 . 00 = leaky bucket configuration 0 01 = leaky bucket configuration 1 10 = leaky bucket configuration 2 11 = leaky bucket configuration 3 bits 3 to 0: input clock no minal frequency (freq[3:0]). this field specifies the input clock?s nominal frequency. freq must be set to 0000 if divn = 1. see section 7.4.2 . 0000 = 8khz 0001 = 1544khz or 2048khz (as determined by sonsdh bit in the mcr3 register) 0010 = 6.48mhz 0011 = 19.44mhz 0100 = 25.92mhz 0101 = 38.88mhz 0110 = 51.84mhz 0111 = 77.76mhz 1000 = 155.52mhz (only valid for ic5 and ic6) 1001 = 2khz 1010 = 4khz 1011 = 6312khz 1100?1111 {unused values} freq[3:0] default values: icr1?icr4: 0000b icr5?icr10: 0011b icr11: 0010b if mastslv = 0 0011b if mastslv = 1 icr12?icr14: 0001b note that the icr11 default value is set bas ed on the state of the mastslv pin when the rst pin is asserted. see section 7.12 .
DS3101 stratum 3/3e timing card ic 77 of 149 register name: valcr1 register description: input clock valid control register 1 register address: 30h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ic8 ic7 ic6 ic5 ic4 ic3 ic2 ic1 default 1 1 1 1 1 1 1 1 bits 7 to 0: input clock valid control (ic8 to ic1). these control bits can be used to force input clocks to be considered invalid. if a clock is invalidated by one of these c ontrol bits it will not appear in the priority table in the ptab1 and ptab2 registers, even if the clock is otherwise valid. one key application for these control bits is to force clocks invalid that are declared invalid in the ot her DS3101 device of a redundant pair. note that setting a valcr bit low has no effect on the corresponding bit in the valsr registers. see sections 7.6.2 and 7.9.1 . 0 = force invalid 1 = do not force invalid; determine validity normally register name: valcr2 register description: input clock valid control register 2 register address: 31h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? ? ic14 ic13 ic12 ic11 ic10 ic9 default 0 0 1 1 1 1 1 1 bits 5 to 0: input clock valid control (ic14 to ic9). these bits have the same behavior as the bits in valcr1 but for the ic9 through ic14 input clocks.
DS3101 stratum 3/3e timing card ic 78 of 149 register name: mcr1 register description: master configuration register 1 register address: 32h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name rst ? ? ? ? t0state[2:0] default 0 0 0 0 0 0 0 0 bit 7: device reset (rst). when this bit is high the entire device is held in reset, and all register fields, except the rst bit itself, are reset to their default states. when rst is active, the register fields with pin-programmed defaults do not latch their values from the corresponding input pins. instead these fields are reset to the default values that were latched from the pins when the rst pin was last active. see section 7.12 . 0 = normal operation 1 = reset bits 2 to 0: t0 dpll state control (t0state). this field allows the t0 dpll state machine to be forced to a specified state. the state machine will remain in the forc ed state, and therefore cannot react to alarms and other events, as long as t0state is not equal to 000. see section 7.7.1 . 000 = automatic (normal state machine operation) 001 = free-run 010 = holdover 011 = {unused value} 100 = locked 101 = prelocked 2 110 = prelocked 111 = loss-of-lock
DS3101 stratum 3/3e timing card ic 79 of 149 register name: mcr2 register description: master configuration register 2 register address: 33h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? ? ? ? t0force[3:0] default 0 0 0 0 1 1 1 1 bits 3 to 0: t0 dpll force selected reference (t0force[3:0]). this field provides a way to force a specified input clock to be the selected reference for the t0 dpll. inte rnally this is accomplished by forcing the clock to have the highest priority (as specified in ptab1 :ref1). in revertive mode ( mcr3 :revert = 1) the forced clock automatically becomes the selected reference (as specified in ptab1 :selref) as well. in nonrevertive mode, the forced clock only becomes the selected reference when t he existing selected reference is invalidated or made unavailable for selection. when a reference is forced, the activity monitor and frequ ency monitor for that input and the t0 dpll?s loss-of-lock timeout logic all continue to operate and affect the relevant isr , valsr and msr register bits. however, when the reference is declared invalid the t0 dpll is not allowed to switch to another input clock. the t0 dpll continues to respond to the fast activity monitor and the invali date-on-event logic in the cc receivers (register mcr5 ), transitioning to miniholdover in response to short-term ev ents and to full holdover in response to longer events. see section 7.6.3 . 0000 = automatic source selection (normal operation) 0001 = force to ic1 0010 = force to ic2 0011 = force to ic3 0100 = force to ic4 0101 = force to ic5 0110 = force to ic6 0111 = force to ic7 1000 = force to ic8 1001 = force to ic9 1010 = force to ic10 1011 = force to ic11 1100 = force to ic12 1101 = force to ic13 1110 = force to ic14 1111 = automatic source selection (normal operation)
DS3101 stratum 3/3e timing card ic 80 of 149 register name: mcr3 register description: master configuration register 3 register address: 34h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name aefsen lkato xoedge manh o efsen sonsdh mastslv revert default 1 1 0 0 0 see below see below 0 bit 7: auto external frame sync enable (aefsen). see section 7.9.3 . 0 = efsen bit (bit 3 below) enables and disables the external frame sync on the sync2k pin 1 = the external frame sync is enabled when efsen = 1 and the t0 dpll is locked to the input clock specified in the source field of fscr3 . bit 6: phase lock alarm timeout (lkato). this bit controls how phase alarms on input clocks can be terminated. phase alarms are indicated by the lock bits in isr registers 0 = phase alarms on input clocks can only be cancelled by software 1 = phase alarms are automatically cancelled after a timeout period of 128 seconds bit 5: local oscillator edge (xoedge). this bit specifies the si gnificant clock e dge of the local oscillator clock signal on the refclk input pin. the faster edge sh ould be selected for best jitter performance. see section 7.3 . 0 = rising edge 1 = falling edge bit 4: manual holdover (manho). when this bit is set to 1 the t0 dpll holdover frequency is set by the hofreq field in the hocr1 , hocr2 and hocr3 registers. when manho = 1 it has priority over any other holdover control fields. see section 7.7.1.6 . 0 = standard holdover: holdover frequency is lear ned by the t0 dpll from the selected reference 1 = manual holdover: holdover frequency is taken from the hofreq field bit 3: external frame sync enable (efsen). when this bit is set to 1 the t0 dpll looks for a reference frame sync pulse on the sync2k pin. see the aefsen bit des cription above for more information. see section 7.9.3 . 0 = disable external frame sync; ignore sync2k pin 1 = enable external frame sync on sync2k pin bit 2: sonet or sdh frequencies (sonsdh). this bit specifies the clock rate for input clocks with freq=0001 in the icr registers (20h to 2dh). during reset the default va lue of this bit is latched from the sonsdh pin. see section 7.4.2 . 0 = 2048khz 1 = 1544 hz bit 1: master or slave configuration (mastslv). this read-only bit indicates the state of the mastslv pin. this bit therefore does not have a fix ed default value. to disable the master-s lave pin feature and give software the ability to configure devices as either master or slave, wire the mastslv pin high (master mode) on both devices. see section 7.9 . 0 = slave mode. in this mode input clock ic11 is set to priority 1 (highest), the t0 dpll is set to acquisition bandwidth, revertive mode is enabled, and phase build-out is disabled. 1 = master mode. in this mode all setting are configured by conf iguration registers. bit 0: revertive mode (revert). this bit configures the t0 dpll for re vertive or non-revertive operation. (the t4 dpll is always revertive). in revertive mode, if an input clock with a higher priority than the selected reference becomes valid, the higher-priority reference immediatel y becomes the selected reference. in nonrevertive mode, the higher priority reference does not immediately beco me the selected reference but does become the highest- priority reference in the priority table (ref1 field in the ptab1 register). see section 7.6.2 . when the device is in slave mode (mastslv pin = 0) values written to this field are latched, but the value read is always 1 to indicate that the device is forced into revertive mode. see section 7.9.1 . 0 = nonrevertive mode 1 = revertive mode
DS3101 stratum 3/3e timing card ic 81 of 149 register name: mcr4 register description: master configuration register 4 register address: 35h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name lkt4t0 t4dfb ? oc89 t4force[3:0] default 0 1 0 0 0 0 0 0 bit 7: lock t4 to t0 (lkt4t0). when this bit is set to 0 the t4 path operates independently from the t0 path. when it is set to 1 the t4 path locks to the output of the t0 dpll, which allows the t4 path to be used to synthesize additional clock frequencies that ar e locked to the t0 reference. see section 7.8.2.2 . 0 = t4 path operates independently from t0 path 1 = t4 dpll locks to the output of the t0 dpll bit 6: t4 digital feedback mode (t4dfb). see section 7.8.2.2 . 0 = analog feedback mode 1 = digital feedback mode bit 4: source control for clock outputs 8 and 9 (oc89). see section 7.8.2.4 . 0 = oc8 and oc9 generated from t4 dpll 1 = oc8 and oc9 generated from t0 dpll bits 3 to 0: t4 dpll force selected reference (t4force[3:0]). this field provides a way to force a specified input clock to be the selected reference for the t4 dpll. inte rnally this is accomplished by forcing the clock to have the highest priority (as specified in ptab1 :ref1). since the t4 dpll always operates in revertive mode, the forced clock automatically becomes t he selected reference (as specified in ptab1 :selref) as well. when a reference is forced, the activity monitor and frequenc y monitor for that input continue to operate and affect the relevant isr , valsr and msr register bits. however, when the reference is declared invalid, the t4 dpll is not allowed to switch to another input clock. see section 7.6.3 . 0000 = automatic (normal operation) 0001 = force to ic1 0010 = force to ic2 0011 = force to ic3 0100 = force to ic4 0101 = force to ic5 0110 = force to ic6 0111 = force to ic7 1000 = force to ic8 1001 = force to ic9 1010 = force to ic10 1011 = force to ic11 1100 = force to ic12 1101 = force to ic13 1110 = force to ic14 1111 = automatic (normal operation)
DS3101 stratum 3/3e timing card ic 82 of 149 register name: mcr5 register description: master configuration register 5 register address: 36h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ccedge biterr ami los ic2sf ic1sf ic6sf ic5sf default 0 0 0 0 0 0 1 0 bit 7: composite clock 8khz edge (ccedge). this bit specifies the 8khz clock edge in the incoming composite clock signals on inputs ic1 and ic2. see section 7.10.1 . 0 = the leading edge of the pulse following the bpv 1 = the leading edge of the bpv bit 6: increment the activity monitor on bit errors (biterr). if this bit is set to 1, then the detection of a deviation from the one-bpv-in-eight pattern on ic1 or ic 2 (in composite clock mode) is considered an irregularity by the corresponding activity monitor. the activity monitors increment thei r leaky bucket accumulators once for each 128ms interval in which irregularities occur. see section 7.10.1 . 0 = bit errors do not increment the input clock activity monitors 1 = bit errors do increment the input clock activity monitors bit 5: invalidate on ami violation (ami). if this bit is set to 1, then the detection of a deviation from the one-bpv- in-eight pattern in each of two consecutive 8-bit periods on ic1 or ic2 (in composite clock mode) automatically invalidates the offending clock. see section 7.10.1 . 0 = do not invalidate on ami violation 1 = invalidate on incorrect ami violation bit 4: invalidate on loss of signal (los). if this bit is set to 1, then the detection of two consecutive zeros on ic1 or ic2 (in composite clock mode) automatically invalidates the offending clock. see section 7.10.1 . 0 = do not invalidate on los 1 = invalidate on los bit 3: input clock 2 signal format (ic2sf). see section 7.10.1 . 0 = ami 64khz composite clock on the ic2a pin 1 = cmos/ttl on the ic2 pin bit 2: input clock 1 signal format (ic1sf). see section 7.10.1 . 0 = ami 64 khz composite clock on the ic1a pin 1 = cmos/ttl on the ic1 pin bit 1: input clock 6 signal format (ic6sf). for backward compatibility this bit can be written to and read back, but it does not affect the ic6pos/neg inputs pins. see section 7.4.1 . 0 = lvds compatible 1 = lvpecl compatible (default) bit 0: input clock 5 signal format (ic5sf). for backward compatibility this bit can be written to and read back, but it does not affect the ic6pos/neg inputs pins. see section 7.4.1 . 0 = lvds compatible (default) 1 = lvpecl compatible
DS3101 stratum 3/3e timing card ic 83 of 149 register name: ifsr register description: microprocessor interface se lection status register register address: 37h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? ? ? ? ? ifsel[2:0] default 0 0 0 0 0 set by ifsel[2:0] pins when rst = 0 bits 2 to 0: microprocessor interface selection (ifsel[2:0]). this read-only field shows the current state of the ifsel[2:0] pins. when rst = 0 the state of the ifsel pins is latched into the microprocessor interface control register ( ifcr ). after rst is brought high, the ifsel pins are ignored by the interface control logic and can be used as general purpose inputs whose values are shown in this register field. see section 7.10 . register name: mcr6 register description: master configuration register 6 register address: 38h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name dig2af dig2ss dig1ss ? ? ? ? ? default 0 see below see below 1 1 1 1 1 bit 7: digital2 alternate frequency (dig2af). see section 7.8.2.1 . 0 = digital2 frequency specified by dig2ss and mcr7 :dig2f. 1 = digital2 frequency is 6312khz (must set dig2ss = 0 and mcr7 :dig2f = 00) bit 6: digital2 sonet or sdh frequencies (dig2ss). this bit specifies whether the clock rates generated by the digital2 clock synthesizer are mult iples of 1.544mhz (sonet compatible ) or multiples of 2.048mhz (sdh compatible). the specific multiple is set in the dig2f field of the mcr7 register. when rst = 0 the default value of this bit is latched from the sonsdh pin. see section 7.8.2.1 . 0 = multiples of 2048khz 1 = multiples of 1544khz bit 5: digital1 sonet or sdh frequencies (dig1ss). this bit specifies whether the clock rates generated by the digital1 clock synthesizer are multiples of 1544khz (sonet compatible) or multiples of 2048khz (sdh compatible). the specific multiple is set in the dig1f field of the mcr7 register. when rst = 0 the default value of this bit is latched from the sonsdh pin. see section 7.8.2.1 . 0 = multiples of 2048khz 1 = multiples of 1544khz
DS3101 stratum 3/3e timing card ic 84 of 149 register name: mcr7 register description: master configuration register 7 register address: 39h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name dig2f[1:0] dig1f[1:0] ? ? ? ? default 0 0 0 0 1 0 0 0 bits 7 to 6: digital2 frequency (dig2f[1:0]). this field and dig2ss of mcr6 configure the frequency of the digital2 clock synthesizer. see section 7.8.2.1 . dig2ss = 1 dig2ss = 0 00 = 1544khz 00 = 2048khz 01 = 3088khz 01 = 4096khz 10 = 6176khz 10 = 8192khz 11 = 12352khz 11 = 16384khz bits 5 to 4: digital1 frequency (dig1f[1:0]). this field and dig1ss of mcr6 configure the frequency of the digital1 clock synthesizer. see section 7.8.2.1 . dig1ss = 1 dig1ss = 0 00 = 1544khz 00 = 2048khz 01 = 3088khz 01 = 4096khz 10 = 6176khz 10 = 8192khz 11 = 12352khz 11 = 16384khz register name: mcr8 register description: master configuration register 8 register address: 3ah bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? ? oc8400 oc8no8 oc7sf oc6sf default 1 1 0 0 0 1 1 0 bit 5: output clock 8, 400hz component enable (oc8400). see section 7.10.2 . 0 = 400 hz component disabled 1 = 400 hz component enabled bit 4: output clock 8, 8khz component disable (oc8no8). see section 7.10.2 . 0 = 8 khz component enabled 1 = 8 khz component disabled bits 3 to 2: output clock 7 control (oc7sf[1:0]). see section 7.8.1 . 00 = output disabled 01 = 3v lvds compatible (default) 10 = 3v lvds compatible 11 = 3v lvds compatible bits 1 to 0: clock output 6 control (oc6sf[1:0]). see section 7.8.1 . 00 = output disabled 01 = 3v lvds compatible 10 = 3v lvds compatible (default) 11 = 3v lvds compatible
DS3101 stratum 3/3e timing card ic 85 of 149 register name: mcr9 register description: master configuration register 9 register address: 3bh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name autobw ? ? ? limint pfd180 ? ? default 1 1 1 1 1 0 1 1 bit 7: automatic bandwidth selection (autobw). when the device is in slave mode (mastslv pin = 0), this field is ignored and the t0 dpll is forced to use acquisition bandwidth. see section 7.7.3 . 0 = always selects locked bandwidth from the t0lbw register 1 = automatically selects either locked bandwidth ( t0lbw register) or acquisition bandwidth ( t0abw register) as appropriate bit 3: limit integral path (limint). when this bit is set to 1, the t0 dpll?s integral path is limited (i.e., frozen) when the dpll reaches minimum or maximum fr equency, as set by the hardlim field in dlimit1 and dlimit2 . when the integral path is frozen, the current dpll frequency in registers freq1 , freq2 and freq3 is also frozen. setting limint = 1 minimizes overshoot when the dpll is pulling in. see section 7.7.3 . 0 = do not freeze integral path at min/max frequency 1 = freeze integral path at min/max frequency bit 2: 180 pfd enable (pfd180). if test1 :d180 = 1, then pfd180 has no effect. 0 = use 180 phase detector (nearest edge locking mode) 1 = use 180 phase-frequency detector
DS3101 stratum 3/3e timing card ic 86 of 149 register name: mclk1 register description: master clock frequency adjustment register 1 register address: 3ch bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name mclkfreq[7:0] default 1 0 0 1 1 0 0 1 the mclk1 and mclk2 regist ers must be read consecutively and wr itten consecutively. see section 8.3 . bits 7 to 0: master clock freque ncy adjustment (mclkfreq[7:0]). the full 16-bit mclkfreq[15:0] field spans this register and mclk2. mclkfreq is an unsigned integer that adjusts the frequency of the internal 204.8mhz master clock with respect to the frequency of t he local oscillator clock on the refclk pin by up to +514ppm and -771ppm. the master clock adjustment has the effe ct of speeding up the master clock with a positive adjustment and slowing it down with a negative adjustment. for example, if the oscillator connected to refclk has an offset of +1ppm then the adjustment should be -1ppm to correct the offset. the formulas below translate adjustments to register valu es and vice versa. the def ault register value of 39,321 corresponds to 0ppm. see section 7.3 . mclkfreq[15:0] = adjustment_in_ppm / 0.0196229 + 39,321 adjustment_in_ppm = ( mclkfreq[15:0] - 39,321 ) x 0.0196229 register name: mclk2 register description: master clock frequency adjustment register 2 register address: 3dh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name mlckfreq[15:8] default 1 0 0 1 1 0 0 1 bits 7 to 0: master clock frequency adjustment (mclkfreq[15:8]). see the mclk1 register description.
DS3101 stratum 3/3e timing card ic 87 of 149 register name: hocr1 register description: holdover configuration register 1 register address: 3eh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name hofreq[7:0] default 0 0 0 0 0 0 0 0 bits 7 to 0: holdover frequency (hofreq[7:0]). the full 19-bit hofreq[18:0] field spans this register, hocr2 and hocr3 . hofreq is a two?s-complement signed integer, and it expresses the holdover frequency as an offset with respect to the master clock frequency (see section 7.3 ). writing this field sets the t0 dpll?s manual holdover frequency, which is used when manho = 1 in the mcr3 register. when hocr3 :rdavg = 0, reading the hofreq field returns the manual holdover value previously written. when rdavg = 1, reading the hofreq field returns the t0 dpll?s averaged frequency, either the fast average (if hocr3 :fast = 1) or the slow average (if fast = 0). the hofreq field has the same size and format as the freq[18:0] field ( freq1 , freq2 and freq3 registers) to allow software to read freq, filter the value, and then write to hofreq. holdover frequency offset in ppm is equal to hofreq[18:0] x 0.0003068. see section 7.7.1.6 . note: after either hocr3 :rdavg or hocr3 :fast is changed, system software must wait at least 50 s before reading the corresponding holdover valu e from the hofreq[18:0] field. register name: hocr2 register description: holdover configuration register 2 register address: 3fh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name hofreq[15:8] default 0 0 0 0 0 0 0 0 bits 7 to 0: holdover frequency (hofreq[15:8]). see the hocr1 register description.
DS3101 stratum 3/3e timing card ic 88 of 149 register name: hocr3 register description: holdover configuration register 3 register address: 40h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name avg fast rdavg miniho[1:0] hofreq[18:16] default 1 0 0 0 1 0 0 0 see section 8.3 for important information about writing and reading this register. bit 7: averaging (avg). when this bit is set to 1 the t0 dpll uses the averaged frequency value during holdover mode. when manho = 1 in the mcr3 register, this bit is ignored. see section 7.7.1.6 . 0 = not averaged frequency; holdover frequency is eit her manual (manho = 1) or instantaneously frozen 1 = averaged frequency (averaging rate set by the fast bit below) bit 6: fast averaging (fast). this bit controls the averaging rate used in the t0 dpll?s frequency averager. fast averaging has a -3db response point of approximately 8 minutes. slow averaging has a -3db response point of approximately 110 minutes. see section 7.7.1.6 . 0 = slow frequency averaging 1 = fast frequency averaging bit 5: read average (rdavg). this bit controls which value is accessed when reading the hofreq field: the manual holdover frequency or the t0 dpll?s averaged frequenc y. this allows control software, optionally, to make use of the averager and manual holdover mode in a software-controlled holdover algorithm. see section 7.7.1.6 . 0 = read the manual holdover frequency value previously written 1 = read the averaged frequency bits 4 to 3: miniholdover mode (miniho). miniholdover is the state of the t0 dpll where it is in the locked state but has temporarily lost its input. in miniholdover the dp ll behaves exactly the same as in holdover but with holdover frequency selected as spec ified by this field. see section 7.7.1.7 . 00 = frequency determined in the same way as holdover mode 01 = frequency instantaneously frozen (i.e., as if avg = 0) 10 = frequency taken from fast averager (i.e., as if avg = 1 and fast = 1) 11 = frequency taken from slow averager (i.e., as if avg = 1 and fast = 0) bits 2 to 0: holdover frequency (hofreq[18:16]). see the hocr1 register description.
DS3101 stratum 3/3e timing card ic 89 of 149 register name: dlimit1 register description: dpll frequency limit register 1 register address: 41h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name hardlim[7:0] default 0 1 1 1 0 1 1 0 the dlimit1 and dlimit2 registers must be read consec utively and written consecutively. see section 8.3 . bits 7 to 0: dpll hard frequency limit (hardlim[7:0]). the full 10-bit hardlim[9:0] field spans this register and dlimit2 . hardlim is an unsigned integer that specifies the ha rd frequency limit or pull-in/hold-in range of the t0 dpll. when frequency limit detection is enabled by setting fllol = 1 in the dlimit3 register, if the dpll frequency exceeds the hard limit then the dpll declare s loss-of-lock. the hard frequency limit in ppm is hardlim[9:0] x 0.078. the default value is normally 9.2ppm. if external reference switching mode is enabled during reset (see section 7.6.5 ), the default value is configured to 79.794ppm (3ffh). see section 7.7.6 . register name: dlimit2 register description: dpll frequency limit register 2 register address: 42h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? ? ? ? ? ? hardlim[9:8] default 0 0 0 0 0 0 0 0 bits 1 to 0: dpll hard frequency limit (hardlim[9:8]). see the dlimit1 register description.
DS3101 stratum 3/3e timing card ic 90 of 149 register name: ier1 register description: interrupt enable register 1 register address: 43h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ic8 ic7 ic6 ic5 ic4 ic3 ic2 ic1 default 0 0 0 0 0 0 0 0 bits 7 to 0: interrupt enable for input clock status change (ic8 to ic1). each of these bits is an interrupt enable control for the corresponding bit in the msr1 register. 0 = mask the interrupt 1 = enable the interrupt register name: ier2 register description: interrupt enable register 2 register address: 44h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name state srfail ic14 ic13 ic12 ic11 ic10 ic9 default 0 0 0 0 0 0 0 0 bit 7: interrupt enable for t0 dpll state change (state). this bit is an interrupt enable for the state bit in the msr2 register. 0 = mask the interrupt 1 = enable the interrupt bit 6: interrupt enable for sel ected reference failed (srfail). this bit is an interrupt enable for the srfail bit in the msr2 register. 0 = mask the interrupt 1 = enable the interrupt bits 5 to 0: interrupt enable for input clock status change (ic14 to ic9). each of these bits is an interrupt enable control for the corresponding bit in the msr2 register. 0 = mask the interrupt 1 = enable the interrupt
DS3101 stratum 3/3e timing card ic 91 of 149 register name: ier3 register description: interrupt enable register 3 register address: 45h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name fsmon t4lock phmon t4noin ami2 los2 ami1 los1 default 0 0 0 0 0 0 0 0 bit 7: interrupt enable for frame sync input monitor alarm (fsmon). this bit is an interrupt enable for the fsmon bit in the msr3 register. 0 = mask the interrupt 1 = enable the interrupt bit 6: interrupt enable for t4 dpll lock status change (t4lock). this bit is an interrupt enable for the t4lock bit in the msr3 register. 0 = mask the interrupt 1 = enable the interrupt bit 5: interrupt enable for phase monitor alarm (phmon). this bit is an interrupt enable for the phmon bit in the msr3 register. 0 = mask the interrupt 1 = enable the interrupt bit 4: interrupt enable for t4 no valid inputs alarm (t4noin). this bit is an interrupt enable for the t4noin bit in the msr3 register. 0 = mask the interrupt 1 = enable the interrupt bit 3: interrupt enable for ami violation on ic2 (ami2). this bit is an interrupt enable for the ami2 bit in the msr3 register. 0 = mask the interrupt 1 = enable the interrupt bit 2: interrupt enable for los error on ic2 (los2). this bit is an interrupt enable for the los2 bit in the msr3 register. 0 = mask the interrupt 1 = enable the interrupt bit 1: interrupt enable for ami violation on ic1 (ami1). this bit is an interrupt enable for the ami1 bit in the msr3 register. 0 = mask the interrupt 1 = enable the interrupt bit 0: interrupt enable for los error on ic1 (los1). this bit is an interrupt enable for the los1 bit in the msr3 register. 0 = mask the interrupt 1 = enable the interrupt
DS3101 stratum 3/3e timing card ic 92 of 149 register name: divn1 register description: divn register 1 register address: 46h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name divn[7:0] default 1 1 1 1 1 1 1 1 the divn1 and divn2 registers must be read consec utively and written consecutively. see section 8.3 . bits 7 to 0: divn factor (divn[7:0]). the full 15-bit divn[14:0] field spans this register and divn2 . this field contains the integer value used to divide the frequency of input clocks that are config ured for divn mode (divn = 1 in registers icr1 through icr14 ). the frequency is divided by divn[14:0] + 1. divn mode supports a maximum input frequency of 155.52 mhz; therefore, the maximum value of divn[14:0] is 19,439 (i.e., 155.52mhz / 8khz - 1). performance with divn values greater than 19,439 is undefined. see section 7.4.2.3 . register name: divn2 register description: divn register 2 register address: 47h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? divn[14:8] default 0 0 1 1 1 1 1 1 bits 5 to 0: divn factor (divn [14:8]). see the divn1 register description.
DS3101 stratum 3/3e timing card ic 93 of 149 register name: mcr10 register description: master configuration register 10 register address: 48h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name fmonclk srfpin ufsw extsw pbofrz pboen soften harden default 0 0 0 see below 0 1 0 1 bit 7: frequency monitor clock source (fmonclk). this bit specifies the clock source for the input clock frequency monitors. 0 = t0 dpll output 1 = internal master clock bit 6: srfail pin enable (srfpin). when this bit is set to 1, the srfail pin is enabled. when enabled the srfail pin follows the state of the srfail status bit in the msr2 register. this gives the system a very fast indication of the failure of the current reference. see section 7.5.3 . 0 = srfail pin disabled (low) 1 = srfail pin enabled bit 5: ultra-fast switching mode (ufsw). see section 7.6.4 . 0 = disabled 1 = enabled. the current reference source is disqualified after less than three missing clock cycles. bit 4: external reference switching mode (extsw). this bit enables external reference switching mode. in this mode, if the srcsw pin is high the t0 dpll is forced to lock to input ic3 (i f the priority of ic3 is nonzero) or ic5 (if the priority of ic3 is zero) whether or not the selected input has a valid reference signal. if the srcsw pin is low the device is forced to lock to input ic4 (i f the priority of ic4 is nonzero) or ic6 (if the priority of ic4 is zero) whether or not the selected input has a valid reference signal. during reset the default value of this bit is latched from the srcsw pin. this mode only controls the t0 dp ll. the t4 dpll is not affected. see section 7.6.5 . 0 = normal operation 1 = external switching mode bit 3: phase build-out freeze (pbofrz). this bit freezes the current input -output phase relationship and does not allow further phase build-out events to occur. this bi t affects phase build-out in response to input transients (section 7.7.7.2 ) and phase build-out during reference switching (section 7.7.7.3 ). 0 = not frozen 1 = frozen bit 2: phase build-out enable (pboen). when this bit is set to 1 a phase build-out event occurs every time the t0 dpll changes to a new reference, including exiting the holdover and free-run states. when this bit is set to 0, the t0 dpll locks to the new source with ze ro degrees of phase difference. see section 7.7.7 . when the device is in slave mode (mastslv pin = 0) values written to this field are latched, but the value read is always 0 to indicate that the device is forced to have phase build-out disabled. see section 7.9.1 . 0 = disabled 1 = enabled bit 1: soft frequency alarm enable (soften). this bit enables input clock frequency monitoring with the soft alarm limits set in the ilimit and srlimit registers. soft alarms are report ed in the soft status bits of the isr registers. see section 7.5.1 . 0 = disabled 1 = enabled bit 0: hard frequency limit enable (harden). this bit enables input clock frequency monitoring with the hard alarm limits set in the ilimit and srlimit registers. hard alarms are reported in the hard status bits of the isr registers. see section 7.5.1 . 0 = disabled 1 = enabled
DS3101 stratum 3/3e timing card ic 94 of 149 register name: ilimit register description: input clock frequency limit register register address: 49h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name soft[3:0] hard[3:0] default 0 0 1 0 0 0 1 1 bits 7 to 4: soft frequency alarm limit (soft[3:0]). this field is an unsigned integer that specifies the soft frequency alarm limit for all input clocks except the t0 dpll?s selected reference. the soft limit for the selected reference is specified by srlimit :soft[3:0]. the soft alarm limit is only used for monitoring; soft alarms do not invalidate input clocks. the limit in ppm is (soft[3:0] + 1) x 3.81. the default limit is 11.43ppm. soft alarms are reported in the soft status bits of the isr registers. see section 7.5.1 . bits 3 to 0: hard frequency alarm limit (hard[3:0]). this field is an unsigned integer that specifies the hard frequency alarm limit for all input clocks except the t0 dpll ?s selected reference. the hard limit for the selected reference is specified by srlimit :hard[3:0]. hard alarms invalidate input clocks. the limit in ppm is (hard[3:0] + 1) x 3.81. the default limit is 15.24ppm. hard alarms are reported in the hard status bits of the isr registers. see section 7.5.1 . register name: srlimit register description: selected reference frequency limit register register address: 4ah bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name soft[3:0] hard[3:0] default 0 0 1 0 0 0 1 1 bits 7 to 4: soft frequency alarm limit (soft[3:0]). this field is an unsigned integer that specifies the soft frequency alarm limit for the t0 dpll?s selected reference. the soft limit for all other input clocks is specified by ilimit :soft[3:0]. the soft alarm limit is only used for moni toring; soft alarms do not invalidate input clocks. the limit in ppm is (soft[3:0] + 1) x 3.81. the default limit is 11.43ppm. soft alarms are r eported in the soft status bits of the isr registers. see section 7.5.1 . bits 3 to 0: hard frequency alarm limit (hard[3:0]). this field is an unsigned integer that specifies the hard frequency alarm limit for the t0 dpll?s selected reference. the hard limit for all other input clocks is specified by ilimit :hard[3:0]. hard alarms invalidate input clocks. the limit in ppm is (hard[3:0] + 1) x 3.81. the default limit is 15.24ppm. hard alarms are reported in the hard status bits of the isr registers. see section 7.5.1 .
DS3101 stratum 3/3e timing card ic 95 of 149 register name: mcr11 register description: master configuration register 11 register address: 4bh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? ? ? t4t0 fmeasin[3:0] default 0 0 0 0 0 0 0 0 bit 4: t4 or t0 path select (t4t0). this bit specifies which path is being ac cessed when reads or writes are made to the following registers: ptab1 , ptab2 , freq1 , freq2 , freq3 , ipr1 to ipr7 , phase1 , and phase2 . 0 = t0 path 1 = t4 path bits 3 to 0: frequency measurement input select (fmeasin[3:0]). this field specifies the input clock for the frequency measurement reported in the fmeas register. see section 7.5.1 . 0000 = {unused value} 0001 = ic1 0010 = ic2 0011 = ic3 0100 = ic4 0101 = ic5 0110 = ic6 0111 = ic7 1000 = ic8 1001 = ic9 1010 = ic10 1011 = ic11 1100 = ic12 1101 = ic13 1110 = ic14 1111 = {unused value} register name: fmeas register description: frequency measurement register register address: 4ch bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name fmeas[7:0] default 0 0 0 0 0 0 0 0 bits 7 to 0: measured frequency (fmeas[7:0]). this read-only field indicates the measured frequency of the input clock specified in the fmeasin field of the mcr11 register. fmeas is a two?s- complement signed integer that expresses the frequency as an offset with respect to the frequency monitor clock (either the internal master clock or the output of the t0 dpll, dependi ng on the setting of the fmonclk bit in the mcr10 register). the measured frequency is fmeas[ 7:0] x 3.81ppm. see section 7.5.1 .
DS3101 stratum 3/3e timing card ic 96 of 149 register name: dlimit3 register description: dpll frequency limit register 3 register address: 4dh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name fllol softlim[6:0] default 1 0 0 0 1 1 1 0 bit 7: frequency limit loss of lock (fllol). when this bit is set to 1, the t0 and t4 dplls internally declare loss-of-lock when their hard limits are reached. the t0 dpll hard frequency limi t is set in the hardlim[9:0] field in the dlimit1 and dlimit2 registers. the t4 dpll hard frequency limit is fixed at 80ppm.see section 7.7.6 . 0 = dpll declares loss-of-lock normally 1 = dpll also declares loss-of-lock when the hard frequency limit is reached bits 6 to 0: dpll soft frequency limit (softlim6:0]). this field is an unsigned integer that specifies the soft frequency limit for the t0 and t4 dplls. the soft limit is only used for monitoring; exceeding this limit does not cause loss-of-lock. the limit in ppm is softlim[6:0] x 0.628. the default value is 8.79ppm. when the t0 dpll frequency exceeds the soft limit the t0soft status bit is set in the opstate register. when the t4 dpll frequency exceeds the soft limit the t4soft status bit is set in opstate . see section 7.7.6 .
DS3101 stratum 3/3e timing card ic 97 of 149 register name: ier4 register description: interrupt enable register 4 register address: 4eh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name fhordy shordy ? ? ic2no4 ic1no4 ic2no8 ic1no8 default 0 0 0 0 0 0 0 0 bit 7: interrupt enable for fast holdover frequency ready (fhordy). this bit is an interrupt enable for the fhordy bit in the msr4 register. 0 = mask the interrupt 1 = enable the interrupt bit 6: interrupt enable for slow holdover frequency ready (shordy). this bit is an interrupt enable for the shordy bit in the msr4 register. 0 = mask the interrupt 1 = enable the interrupt bit 3: interrupt enable for input clock 2 has no 400hz component (ic2no4). this bit is an interrupt enable for the ic2no4 bit in the msr4 register. 0 = mask the interrupt 1 = enable the interrupt bit 2: interrupt enable for input clock 1 has no 400hz component (ic1no4). this bit is an interrupt enable for the ic1no4 bit in the msr4 register. 0 = mask the interrupt 1 = enable the interrupt bit 1: interrupt enable for input clock 2 has no 8khz component (ic2no8). this bit is an interrupt enable for the ic2no8 bit in the msr4 register. 0 = mask the interrupt 1 = enable the interrupt bit 0: interrupt enable for input clock 1 has no 8khz component (ic1no8). this bit is an interrupt enable for the ic1no8 bit in the msr4 register. 0 = mask the interrupt 1 = enable the interrupt
DS3101 stratum 3/3e timing card ic 98 of 149 register name: lb0u register description: leaky bucket 0 upper threshold register register address: 50h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name lb0u[7:0] default 0 0 0 0 0 1 1 0 bits 7 to 0: leaky bucket 0 upper threshold (lb0u[7:0]). when the leaky bucket accumulator is equal to the value stored in this field, the activity monitor declares an activity alarm by setting the input clock?s act bit in the appropriate isr register. registers lb0u , lb0l , lb0s , and lb0d together specify leaky bucket configuration 0. see section 7.5.2 . register name: lb0l register description: leaky bucket 0 lower threshold register register address: 51h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name lb0l[7:0] default 0 0 0 0 0 1 0 0 bits 7 to 0: leaky bucket 0 lower threshold (lb0l[7:0]). when the leaky bucket accumulator is equal to the value stored in this field, the activity monitoring logic clears the activity alarm (if previously declared) by clearing the input clock?s act bit in the appropriate isr register. registers lb0u , lb0l , lb0s , and lb0d together specify leaky bucket configuration 0. see section 7.5.2 . register name: lb0s register description: leaky bucket 0 size register register address: 52h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name lb0s[7:0] default 0 0 0 0 1 0 0 0 bits 7 to 0: leaky bucket 0 size (lb0s[7:0]). this field specifies the maximum value of the leaky bucket. the accumulator cannot increment past this value. registers lb0u , lb0l , lb0s , and lb0d together specify leaky bucket configuration 0. see section 7.5.2 .
DS3101 stratum 3/3e timing card ic 99 of 149 register name: lb0d register description: leaky bucket 0 decay rate register register address: 53h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? ? ? ? ? ? lb0d[1:0] default 0 0 0 0 0 0 0 1 bits 1 to 0: leaky bucket 0 decay rate (lb0d[1:0]). this field specifies the decay or ?leak? rate of the leaky bucket accumulator. for each period of 1, 2, 4, or 8 128ms intervals in which no irregularities are detected on the input clock, the accumulator decrements by 1. registers lb0u , lb0l , lb0s , and lb0d together specify leaky bucket configuration 0. see section 7.5.2 . 00 = decrement every 128ms (8 units/second) 01 = decrement every 256ms (4 units/second) 10 = decrement every 512ms (2 units/second) 11 = decrement every 1024ms (1 unit/second)
DS3101 stratum 3/3e timing card ic 100 of 149 register name: lb1u, lb2u, lb3u register description: leaky bucket 1/2/3 upper threshold register register address: 54h, 58h, 5ch bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name lbxu[7:0] default 0 0 0 0 0 1 1 0 bits 7 to 0: leaky bucket ?x? upper threshold (lbxu[7:0]). see the lb0u register description. registers lb1u , lb1l , lb1s , and lb1d together specify leaky bu cket configuration 1. registers lb2u , lb2l , lb2s , and lb2d together specify leaky bu cket configuration 2. registers lb3u , lb3l , lb3s , and lb3d together specify leaky bu cket configuration 3. register name: lb1l, lb2l, lb3l register description: leaky bucket 1/2/3 lower threshold register register address: 55h, 59h, 5dh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name lbxl[7:0] default 0 0 0 0 0 1 0 0 bits 7 to 0: leaky bucket ?x? lower threshold (lbxl[7:0]). see the lb0l register description. registers lb1u , lb1l , lb1s , and lb1d together specify leaky bu cket configuration 1. registers lb2u , lb2l , lb2s , and lb2d together specify leaky bu cket configuration 2. registers lb3u , lb3l , lb3s , and lb3d together specify leaky bu cket configuration 3. register name: lb1s, lb2s, lb3s register description: leaky bucket 1/2/3 size register register address: 56h, 5ah, 5eh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name lbxs[7:0] default 0 0 0 0 1 0 0 0 bits 7 to 0: leaky bucket ?x? size (lbxs[7:0]). see the lb0s register description. registers lb1u , lb1l , lb1s , and lb1d together specify leaky bu cket configuration 1. registers lb2u , lb2l , lb2s , and lb2d together specify leaky bu cket configuration 2. registers lb3u , lb3l , lb3s , and lb3d together specify leaky bu cket configuration 3. register name: lb1d, lb2d, lb3d register description: leaky bucket 1/2/3 decay rate register register address: 57h, 5bh, 5fh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? ? ? ? ? ? lbxd[1:0] default 0 0 0 0 0 0 0 1 bits 1 to 0: leaky bucket ?x? decay rate (lbxd[1:0]). see the lb0d register description. registers lb1u , lb1l , lb1s , and lb1d together configure leaky bucket algorithm 1. registers lb2u , lb2l , lb2s , and lb2d together configure leaky bucket algorithm 2. registers lb3u , lb3l , lb3s , and lb3d together configure leaky bucket algorithm 3.
DS3101 stratum 3/3e timing card ic 101 of 149 register name: ocr1 register description: output configuration register 1 register address: 60h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ofreq2[3:0] ofreq1[3:0] default 1 0 0 0 0 1 0 1 bits 7 to 4: output frequency of oc2 (ofreq2[3:0]). this field specifies the frequency of output clock oc2. the frequencies of the t0 apll and t4 apll are configured in the t0cr1 and t4cr1 registers. the digital1 and digital2 frequencies are configured in the mcr7 register. see section 7.8.2.3 . note that if the t4 dpll is configured for 62.5mhz ( t4cr1 :t4freq = 1001) and the t4 apll is configured to lock to the t4 dpll ( t0cr1 :t4apt0 = 0), then ofreq2 = 1100 specifies t4 apll frequency divided by 10 to give an output frequency of 25mhz. 0000 = output disabled (i.e., low) 0001 = 2khz 0010 = 8khz 0011 = digital2 (see table 7-8 ) 0100 = digital1 (see table 7-8 ) 0101 = t0 apll frequency divided by 48 0110 = t0 apll frequency divided by 16 0111 = t0 apll frequency divided by 12 1000 = t0 apll frequency divided by 8 1001 = t0 apll frequency divided by 6 1010 = t0 apll frequency divided by 4 1011 = t4 apll frequency divided by 64 1100 = t4 apll frequency divided by 48 (or by 10, see note above) 1101 = t4 apll frequency divided by 16 1110 = t4 apll frequency divided by 8 1111 = t4 apll frequency divided by 4 bits 3 to 0: output frequency of oc1 (ofreq1[3:0]). this field specifies the frequency of output clock oc1. the frequencies of the t0 apll and t4 apll are configured in the t0cr1 and t4cr1 registers. the digital1 and digital2 frequencies are configured in the mcr7 register. see section 7.8.2.3 . note that if the t4 dpll is configured for 62.5mhz ( t4cr1 :t4freq = 1001) and the t4 apll is configured to lock to the t4 dpll ( t0cr1 :t4apt0 = 0), then ofreq1 = 1100 specifies t4 apll frequency divided by 10 to give an output frequency of 25mhz. 0000 = output disabled (i.e., low) 0001 = 2khz 0010 = 8khz 0011 = digital2 (see table 7-8 ) 0100 = digital1 (see table 7-8 ) 0101 = t0 apll frequency divided by 48 0110 = t0 apll frequency divided by 16 0111 = t0 apll frequency divided by 12 1000 = t0 apll frequency divided by 8 1001 = t0 apll frequency divided by 6 1010 = t0 apll frequency divided by 4 1011 = t4 apll frequency divided by 64 1100 = t4 apll frequency divided by 48 (or by 10, see note above) 1101 = t4 apll frequency divided by 16 1110 = t4 apll frequency divided by 8 1111 = t4 apll frequency divided by 4
DS3101 stratum 3/3e timing card ic 102 of 149 register name: ocr2 register description: output configuration register 2 register address: 61h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ofreq4[3:0] ofreq3[3:0] default 1 0 0 0 0 1 1 0 bits 7 to 4: output frequency of oc4 (ofreq4[3:0]). this field specifies the frequency of output clock oc4. the frequencies of the t0 apll and t4 apll are configured in the t0cr1 and t4cr1 registers. the digital1 and digital2 frequencies are configured in the mcr7 register. see section 7.8.2.3 . note that if the t4 dpll is configured for 62.5mhz ( t4cr1 :t4freq = 1001) and the t4 apll is configured to lock to the t4 dpll ( t0cr1 :t4apt0 = 0), then ofreq4 = 1100 specifies t4 apll frequency divided by 10 to give an output frequency of 25mhz. 0000 = output disabled (i.e., low) 0001 = 2khz 0010 = 8khz 0011 = digital2 (see table 7-8 ) 0100 = digital1 (see table 7-8 ) 0101 = t0 apll frequency divided by 48 0110 = t0 apll frequency divided by 16 0111 = t0 apll frequency divided by 12 1000 = t0 apll frequency divided by 8 1001 = t0 apll frequency divided by 6 1010 = t0 apll frequency divided by 4 1011 = t4 apll frequency divided by 2 1100 = t4 apll frequency divided by 48 (or by 10, see note above) 1101 = t4 apll frequency divided by 16 1110 = t4 apll frequency divided by 8 1111 = t4 apll frequency divided by 4 bits 3 to 0: output frequency of oc3 (ofreq3[3:0]). this field specifies the frequency of output clock oc3. the frequencies of the t0 apll and t4 apll are configured in the t0cr1 and t4cr1 registers. the digital1 and digital2 frequencies are configured in the mcr7 register. see section 7.8.2.3 . note that if the t4 dpll is configured for 62.5mhz ( t4cr1 :t4freq = 1001) and the t4 apll is configured to lock to the t4 dpll ( t0cr1 :t4apt0 = 0), then ofreq3 = 1100 specifies t4 apll frequency divided by 10 to give an output frequency of 25mhz. 0000 = output disabled (i.e., low) 0001 = 2khz 0010 = 8khz 0011 = digital2 (see table 7-8 ) 0100 = digital1 (see table 7-8 ) 0101 = t0 apll frequency divided by 48 0110 = t0 apll frequency divided by 16 0111 = t0 apll frequency divided by 12 1000 = t0 apll frequency divided by 8 1001 = t0 apll frequency divided by 6 1010 = t0 apll frequency divided by 4 1011 = t4 apll frequency divided by 64 1100 = t4 apll frequency divided by 48 (or by 10, see note above) 1101 = t4 apll frequency divided by 16 1110 = t4 apll frequency divided by 8 1111 = t4 apll frequency divided by 4
DS3101 stratum 3/3e timing card ic 103 of 149 register name: ocr3 register description: output configuration register 3 register address: 62h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ofreq6[3:0] ofreq5[3:0] default 1 0 0 0 1 0 1 0 bits 7 to 4: output frequency of oc6 (ofreq6[3:0]). this field specifies the freq uency of output clock output oc6. the frequencies of the t0 apll and t4 apll are configured in the t0cr1 and t4cr1 registers. the digital1 and digital2 frequencies are configured in the mcr7 register. see section 7.8.2.3 . note that if the t4 dpll is configured for 62.5mhz ( t4cr1 :t4freq = 1001) and the t4 apll is configured to lock to the t4 dpll ( t0cr1 :t4apt0 = 0), then ofreq6 = 1100 specifies t4 apll frequency divided by 10 to give an output frequency of 25mhz. 0000 = output disabled (i.e., low) 0001 = 2khz 0010 = 8khz 0011 = t0 apll frequency divided by 2 0100 = digital1 (see table 7-8 ) 0101 = t0 apll frequency 0110 = t0 apll frequency divided by 16 0111 = t0 apll frequency divided by 12 1000 = t0 apll frequency divided by 8 1001 = t0 apll frequency divided by 6 1010 = t0 apll frequency divided by 4 1011 = t4 apll frequency divided by 64 1100 = t4 apll frequency divided by 48 (or by 10, see note above) 1101 = t4 apll frequency divided by 16 1110 = t4 apll frequency divided by 8 1111 = t4 apll frequency divided by 4 bits 3 to 0: output frequency of oc5 (ofreq5[3:0]). this field specifies the frequency of output clock oc5. the frequencies of the t0 apll and t4 apll are configured in the t0cr1 and t4cr1 registers. the digital1 and digital2 frequencies are configured in the mcr7 register. see section 7.8.2.3 . note that if the t4 dpll is configured for 62.5mhz ( t4cr1 :t4freq = 1001) and the t4 apll is configured to lock to the t4 dpll ( t0cr1 :t4apt0 = 0), then ofreq5 = 1100 specifies t4 apll frequency divided by 10 to give an output frequency of 25mhz. 0000 = output disabled (i.e., low) 0001 = 2khz 0010 = 8khz 0011 = digital2 (see table 7-8 ) 0100 = digital1 (see table 7-8 ) 0101 = t0 apll frequency divided by 48 0110 = t0 apll frequency divided by 16 0111 = t0 apll frequency divided by 12 1000 = t0 apll frequency divided by 8 1001 = t0 apll frequency divided by 6 1010 = t0 apll frequency divided by 4 1011 = t4 apll frequency divided by 2 1100 = t4 apll frequency divided by 48 (or by 10, see note above) 1101 = t4 apll frequency divided by 16 1110 = t4 apll frequency divided by 8 1111 = t4 apll frequency divided by 4
DS3101 stratum 3/3e timing card ic 104 of 149 register name: ocr4 register description: output configuration register 4 register address: 63h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name oc11en oc10en oc9en oc8en ofreq7[3:0] default 1 1 1 1 0 1 1 0 bit 7: oc11 enable (oc11en). this configuration bit enables the 2khz output on oc11. see section 7.8.2.5 . 0 = disabled (low) 1 = enabled bit 6: oc10 enable (oc10en). this configuration bit enables the 8khz output on oc10. see section 7.8.2.5 . 0 = disabled (low) 1 = enabled bit 5: oc9 enable (oc9en). this configuration bit enables the 1.544/ 2.048mhz output on oc9. see section 7.8.2.4 . 0 = disabled (low) 1 = enabled bit 4: oc8 enable (oc8en). this configuration bit enables oc8 to tr ansmit a 64khz composite clock signal. see sections 7.8.2.4 and 7.10.2 . 0 = disabled (high impedance) 1 = enabled bits 3 to 0: output frequency of oc7 (ofreq7[3:0]). this field specifies the freq uency of output clock output oc7. the frequencies of the t0 apll and t4 apll are configured in the t0cr1 and t4cr1 registers. the digital1 and digital2 frequencies are configured in the mcr7 register. see section 7.8.2.3 . note that if the t4 dpll is configured for 62.5mhz ( t4cr1 :t4freq = 1001) and the t4 apll is configured to lock to the t4 dpll ( t0cr1 :t4apt0 = 0), then ofreq7 = 1100 specifies t4 apll frequency divided by 10 to give an output frequency of 25mhz. 0000 = output disabled (i.e., low) 0001 = 2khz 0010 = 8khz 0011 = digital2 (see table 7-8 ) 0100 = t0 apll frequency divided by 2 0101 = t0 apll frequency divided by 48 0110 = t0 apll frequency divided by 16 0111 = t0 apll frequency divided by 12 1000 = t0 apll frequency divided by 8 1001 = t0 apll frequency divided by 6 1010 = t0 apll frequency divided by 4 1011 = t4 apll frequency divided by 64 1100 = t4 apll frequency divided by 48 (or by 10, see note above) 1101 = t4 apll frequency divided by 16 1110 = t4 apll frequency divided by 8 1111 = t4 apll frequency divided by 4
DS3101 stratum 3/3e timing card ic 105 of 149 register name: t4cr1 register description: t4 dpll configuration register 1 register address: 64h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? asquel oc8duty oc9son t4freq[3:0] default 0 0 0 see below 0 0 0 1 bit 6: auto-squelch (asquel). when outputs oc8 and oc9 are sourced from the t4 dpll ( mcr4 :oc89 = 0), this configuration bit enables automatic squelching of oc8 and oc9 whenever t4 has no valid input references. when an output is squelched it is forced low. see section 7.8.2.4 . 0 = disable automatic squelching 1 = enable automatic squelching of oc8 and oc9 when t4 has no valid input references bit 5: oc8 duty cycle (oc8duty). see section 7.10.2 . 0 = 50% duty cycle 1 = 5/8 duty cycle bit 4: oc9 sonet/sdh (oc9son). when mcr4 :oc89 = 0, this bit controls the frequency of clock output oc9. when oc89 = 1, this bit ignored and the frequency of oc9 is controlled by the sonsdh bit in mcr3 . during reset the default value of this bit is latched from the sonsdh pin. see section 7.8.2.4 . 0 = 2048khz (sdh) 1 = 1544khz (sonet) bits 3 to 0: t4 dpll fr equency (t4freq[3:0]). this field configures the t4 dpll frequency. the t4 dpll frequency can affect the frequency of the t4 apll, which in turn affects the available output frequencies on clock outputs oc1 to oc7 (see registers ocr1 to ocr4 ). optionally the t4 dpll can be disabled and the t4 apll can be locked to the t0 dpll (see the t4apt0 bit in the t0cr1 register). see section 7.8.2 . t4 dpll frequency t4 apll frequency 0000 = disabled depends on state of t4apt0 in t0cr1 register 0001 = 77.76mhz 311.04mhz (4 x t4 dpll) 0010 = 24.576mhz (12 x e1) 98.304mhz (4 x t4 dpll) 0011 = 32.768mhz (16 x e1) 131.072mhz (4 x t4 dpll) 0100 = 37.056mhz (24 x ds1) 148.224mhz (4 x t4 dpll) 0101 = 24.704mhz (16 x ds1) 98.816mhz (4 x t4 dpll) 0110 = 68.736mhz (2 x e3) 274.944mhz (4 x t4 dpll) 0111 = 44.736mhz (ds3) 178.944mhz (4 x t4 dpll) 1000 = 25.248mhz (4 x 6312 khz) 100.992mhz (4 x t4 dpll) 1001 = 62.500mhz (gbe 16) 250.000mhz (4 x t4 dpll) 1010?1111 = {unused values} {unused values}
DS3101 stratum 3/3e timing card ic 106 of 149 register name: t0cr1 register description: t0 dpll configuration register 1 register address: 65h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name t4mt0 t4apt0 t0ft4[2:0] t0freq[2:0] default 0 0 0 0 0 0 0 1 bit 7: t4 measure t0 phase (t4mt0). when this bit is set to 1 the t4 path is disabled, and the t4 phase detector is configured to measure the phase difference between the selected t0 dp ll input clock and the selected t4 dpll input clock. see section 7.7.10 . 0 = normal operation for the t4 path 1 = enable t4-measure-t0-phase mode bit 6: t4 apll source from t0 (t4apt0). when this bit is set to 1 the t4 output apll locks to the t0 lf output dfs rather than the t4 forward dfs. the t0ft4[1:0] fiel d (below) specifies the t0 dpll frequency. see section 7.8.2 . 0 = t4 apll locks to t4 dpll 1 = t4 apll locks to t0 dpll bits 5 to 3: t0 frequency to t4 apll (t0ft4[2:0]). this field specifies the frequency provided from the t0 lf output dfs to the t4 output apll when the t4apt0 bit is set to 1. this frequency can be different than the frequency specified by t0cr1 :t0freq. values not listed below are unused. see section 7.8.2 . t0 dpll frequency t4 apll frequency 000 = 24.576mhz (12 x e1) 98.304mhz (4 x t0 dpll) 010 = 32.768mhz (16 x e1) 131.072mhz (4 x t0 dpll) 100 = 37.056mhz (24 x ds1) 148.224mhz (4 x t0 dpll) 110 = 24.704mhz (16 x ds1) 98.816mhz (4 x t0 dpll) 111 = 25.248mhz (4 x 6312 khz) 100.992mhz (4 x t0 dpll) bits 2 to 0: t0 dpll frequency (t0freq[2:0]). this field configures the t0 dpll output frequency that is passed to the t0 output apll. the t0 dpll output frequenc y affects the frequency of the t0 output apll, which in turn affects the available output frequenc ies on clock outputs oc1 to oc7 (see registers ocr1 to ocr4 ). see section 7.8.2. t0 dpll frequency t0 apll frequency 000 = 77.76mhz, digital feedback 311.04mhz (4 x t0 dpll) 001 = 77.76mhz, analog feedback 311.04mhz (4 x t0 dpll) 010 = 24.576mhz (12 x e1) 98.304mhz (4 x t0 dpll) 011 = 32.768mhz (16 x e1) 131.072mhz (4 x t0 dpll) 100 = 37.056mhz (24 x ds1) 148.224mhz (4 x t0 dpll) 101 = 24.704mhz (16 x ds1) 98.816mhz (4 x t0 dpll) 110 = 25.248mhz (4 x 6312 khz) 100.992mhz (4 x t0 dpll) 111 = {unused value} {unused value}
DS3101 stratum 3/3e timing card ic 107 of 149 register name: t4bw register description: t4 bandwidth register register address: 66h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? ? ? ? ? ? t4bw[1:0] default 0 0 0 0 0 0 0 0 bits 1 to 0: t4 dpll bandwidth (t4bw[1:0]). see section 7.7.3 . 00 = 18hz 01 = 35hz 10 = 70hz 11 = {unused value} register name: t0lbw register description: t0 locked bandwidth register register address: 67h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? ? ? t0lbw[4:0] default 0 0 0 0 1 0 1 1 bits 4 to 0: t0 dpll locked bandwidth (t0lbw[4:0]). this field configures the bandwidth of the t0 dpll when locked to an input clock. when autobw = 0 in the mcr9 register, the t0lbw bandwidth is used for acquisition and for locked operation. when autobw = 1, t0abw bandwidth is used for acquisition while t0lbw bandwidth is used for locked operation. see section 7.7.3 . 00000 = 0.5mhz 00001 = 1mhz 00010 = 2mhz 00011 = 4mhz 00100 = 8mhz 00101 = 15mhz 00110 = 30mhz 00111 = 60mhz 01000 = 0.1hz 01001 = 0.3hz 01010 = 0.6hz 01011 = 1.2hz 01100 = 2.5hz 01101 = 4hz 01110 = 8hz 01111 = 18hz 10000 = 35hz 10001 = 70hz 10010 to 11111 = {unused values}
DS3101 stratum 3/3e timing card ic 108 of 149 register name: t0abw register description: t0 acquisition bandwidth register register address: 69h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? ? ? t0abw[4:0] default 0 0 0 0 1 1 1 1 bits 4 to 0: t0 dpll acquisition bandwidth (t0abw[4:0]). this field configures the bandwidth of the t0 dpll when acquiring lock. when autobw = 0 in the mcr9 register, the t0lbw bandwidth is used for is used for acquisition and for locked operation. when autobw = 1, t0abw bandwidth is used for acquisition while t0lbw bandwidth is used for locked operation. see section 7.7.3 . 00000 = 0.5mhz 00001 = 1mhz 00010 = 2mhz 00011 = 4mhz 00100 = 8mhz 00101 = 15mhz 00110 = 30mhz 00111 = 60mhz 01000 = 0.1hz 01001 = 0.3hz 01010 = 0.6hz 01011 = 1.2hz 01100 = 2.5hz 01101 = 4hz 01110 = 8hz 01111 = 18hz 10000 = 35hz 10001 = 70hz 10010 to 11111 = {unused values}
DS3101 stratum 3/3e timing card ic 109 of 149 register name: t4cr2 register description: t4 configuration register 2 register address: 6ah bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? pd2ga8k[2:0] ? damp[2:0] default 0 0 0 1 0 0 1 1 bits 6 to 4: phase detector 2 gain, analog feedback, 8khz (pd2ga8k[2:0]). this field specifies the gain of the t4 phase detector 2 in analog feedback mode with an input clock of 8 khz or less. this value is only used if automatic gain selection is enabled by setting pd2en = 1 in the t4cr3 register. analog vs. digital feedback mode is specified in mcr4 :t4dfb. see section 7.7.5 . bits 2 to 0: damping factor (damp[2:0]). this field configures the damping factor of the t4 dpll. damping factor is a function of both damp[2:0] and the t4 dpll bandwidth ( t4bw register). the default value corresponds to a damping factor of 5. see section 7.7.4 . 18hz 35hz 70hz 001 = 1.2 1.2 1.2 010 = 2.5 2.5 2.5 011 = 5 5 5 100 = 5 10 10 101 = 5 10 20 000, 110, and 111 = {unused values} the gain peak for each damping factor is shown below: damping factor gain peak (db) 1.2 0.4 2.5 0.2 5 0.1 10 0.06 20 0.03
DS3101 stratum 3/3e timing card ic 110 of 149 register name: t0cr2 register description: t0 configuration register 2 register address: 6bh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? pd2ga8k[2:0] ? damp[2:0] default 0 0 0 1 0 0 1 1 bits 6 to 4: phase detector 2 gain, analog feedback, 8khz (pd2ga8k[2:0]). this field specifies the gain of the t0 phase detector 2 in analog feedback mode with an input clock of 8khz or less. this value is only used if automatic gain selection is enabled by setting pd2en = 1 in the t0cr3 register. analog vs. digital feedback mode is specified in t0cr1 :t0freq[2:0]. see section 7.7.5 . bits 2 to 0: damping factor (damp[2:0]). this field configures the damping factor of the t0 dpll. damping factor is a function of both damp [2:0] and the t0 dpll bandwidth ( t0abw and t0lbw ). the default value corresponds to a damping factor of 5. see section 7.7.4 . 4hz 8hz 18hz 35hz 70hz 001 = 5 2.5 1.2 1.2 1.2 010 = 5 5 2.5 2.5 2.5 011 = 5 5 5 5 5 100 = 5 5 5 10 10 101 = 5 5 5 10 20 000, 110, and 111 = {unused values} the gain peak for each damping factor is shown below: damping factor gain peak (db) 1.2 0.4 2.5 0.2 5 0.1 10 0.06 20 0.03
DS3101 stratum 3/3e timing card ic 111 of 149 register name: t4cr3 register description: t4 configuration register 3 register address: 6ch bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name pd2en pd2ga[2:0] ? pd2gd[2:0] default 1 1 0 0 0 0 1 0 bit 7: phase detector 2 gain enable (pd2en). when this bit is set to 1, the t4 phase detector 2 is enabled and the gain is determined by the feedback mode. in digital f eedback mode, the gain is set by the pd2gd field. in analog feedback mode the gain is set by the pd2ga field if the input clock frequency is greater than 8khz or by the pd2ga8k field in the t4cr2 register is the input clock frequency is less than or equal to 8khz. analog vs. digital feedback mode is specified in mcr4 :t4dfb. see section 7.7.5 . 0 = disable 1 = enable bits 6 to 4: phase detector 2 gain, analog feedback (pd2ga[2:0]). this field specifies the gain of the t4 phase detector 2 in analog feedback mode with an input cloc k frequency greater than 8khz. this value is only used if automatic gain selection is enabled by setting pd2en = 1. analog vs. digital feedback mode is specified in mcr4 :t4dfb. see section 7.7.5 . bits 2 to 0: phase detector 2 gain, digital feedback (pd2gd[2:0]). this field specifies the gain of the t4 phase detector 2 in digital feedback mode. this value is only us ed if automatic gain selection is enabled by setting pd2en = 1. analog vs. digital feedback mode is specified in mcr4 :t4dfb. see section 7.7.5 .
DS3101 stratum 3/3e timing card ic 112 of 149 register name: t0cr3 register description: t0 configuration register 3 register address: 6dh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name pd2en pd2ga[2:0] ? pd2gd[2:0] default 1 1 0 0 0 0 1 0 bit 7: phase detector 2 gain enable (pd2en). when this bit is set to 1, the t0 phase detector 2 is enabled and the gain is determined by the feedback mode. in digital f eedback mode, the gain is set by the pd2gd field. in analog feedback mode the gain is set by the pd2ga field if the input clock is greater than 8khz or by the pd2ga8k field in the t0cr2 register if the input clock frequency is less than or equal to 8khz. analog vs. digital feedback mode is specified in t0cr1 :t0freq[2:0]. see section 7.7.5 . 0 = disable 1 = enable bits 6 to 4: phase detector 2 gain, analog feedback (pd2ga[2:0]). this field specifies the gain of the t0 phase detector 2 in analog feedback mode with an input cloc k frequency greater than 8khz. this value is only used if automatic gain selection is enabled by setting pd2en = 1. analog vs. digital feedback mode is specified in t0cr1 :t0freq[2:0]. see section 7.7.5 . bits 2 to 0: phase detector 2 gain, digital feedback (pd2gd[2:0]). this field specifies the gain of the t0 phase detector 2 in digital feedback mode. this value is only us ed if automatic gain selection is enabled by setting pd2en = 1. analog vs. digital feedback mode is specified in t0cr1 :t0freq[2:0]. see section 7.7.5 .
DS3101 stratum 3/3e timing card ic 113 of 149 register name: gpcr register description: gpio configuration register register address: 6eh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name gpio4d gpio3d gpio2d gpio1d gpio4o gpio3o gpio2o gpio1o default 0 0 0 0 0 0 0 0 bit 7: gpio4 direction (gpio4d). this bit configures the data direction for the gpio4 pin. when gpio4 is an input its current state can be read from gpsr :gpio4. when gpio4 is an output, its value is controlled by the gpio4o configuration bit. 0 = input 1 = output bit 6: gpio3 direction (gpio3d). this bit configures the data direction for the gpio3 pin. when gpio3 is an input its current state can be read from gpsr :gpio3. when gpio3 is an output, its value is controlled by the gpio3o configuration bit. 0 = input 1 = output bit 5: gpio2 direction (gpio2d). this bit configures the data direction for the gpio2 pin. when gpio2 is an input its current state can be read from gpsr :gpio2. when gpio2 is an output, its value is controlled by the gpio2o configuration bit. 0 = input 1 = output bit 4: gpio1 direction (gpio1d). this bit configures the data direction for the gpio1 pin. when gpio1 is an input its current state can be read from gpsr :gpio1. when gpi13 is an output, its value is controlled by the gpio1o configuration bit. 0 = input 1 = output bit 3: gpio4 output value (gpio4o). when gpio4 is configured as an output (gpio4d = 1) this bit specifies the output value. 0 = low 1 = high bit 2: gpio3 output value (gpio3o). when gpio3 is configured as an output (gpio3d = 1) this bit specifies the output value. 0 = low 1 = high bit 1: gpio2 output value (gpio2o). when gpio2 is configured as an output (gpio2d = 1) this bit specifies the output value. 0 = low 1 = high bit 0: gpio1 output value (gpio1o). when gpio1 is configured as an output (gpio1d = 1) this bit specifies the output value. 0 = low 1 = high
DS3101 stratum 3/3e timing card ic 114 of 149 register name: gpsr register description: gpio status register register address: 6fh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? ? ? ? gpio4 gpio3 gpio2 gpio1 default 0 0 0 0 0 0 0 0 bit 3: gpio4 state (gpio4). this bit indicates the current state of the gpio4 pin. 0 = low 1 = high bit 2: gpio3 state (gpio3). this bit indicates the current state of the gpio3 pin. 0 = low 1 = high bit 2: gpio2 state (gpio2). this bit indicates the current state of the gpio2 pin. 0 = low 1 = high bit 1: gpio1 state (gpio1). this bit indicates the current state of the gpio1 pin. 0 = low 1 = high
DS3101 stratum 3/3e timing card ic 115 of 149 register name: offset1 register description: phase offset register 1 register address: 70h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name offset[7:0] default 0 0 0 0 0 0 0 0 the offset1 and offset2 registers must be read cons ecutively and written cons ecutively. see section 8.3 . bits 7 to 0: phase offset (offset[7:0]). the full 16-bit offset[15:0] field spans this register and the offset2 register. offset is a two?s-complement signed integer th at specifies the desired phase offset between the output clocks and the selected reference. the phase offset in picoseconds is equal to offset[15:0] x actual_internal_clock_period / 2 11 . if the internal clock is at its nominal frequency of 77.76mhz, the phase offset equation simplifies to offset[15:0] x 6.279ps. if, however, the dpll is locked to a reference wh ose frequency is +1ppm from ideal, for example, then the actual internal clock period is 1 ppm shorter and the phase offset is 1ppm smaller. when the offset field is writ ten, the phase of the output clocks is automatically ramped to the new offset value to avoid loss of synchronization. to adjust the phase offset without changing the phase of the output clocks, use the recalibration process enabled by fscr3 :recal. the offset field is ignored when phase build-out is enabled (pboen = 1 in the mcr10 register or pmpben = 1 in the phmon register) and when the dpll is not locked. see section 7.7.8 . register name: offset2 register description: phase offset register 2 register address: 71h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name offset[15:8] default 0 0 0 0 0 0 0 0 bits 7 to 0: phase offset (offset[15:8]). see the offset1 register description.
DS3101 stratum 3/3e timing card ic 116 of 149 register name: pboff register description: phase build-out offset register register address: 72h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? ? pboff[5:0] default 0 0 0 0 0 0 0 0 bits 5 to 0: phase build-out offset register (pboff[5:0]). an uncertainty of up to 5ns is introduced each time a phase build-out event occurs. this uncertainty results in a phase hit on the output. over a large number of phase build-out events the mean error should be zero. the pboff field specifies a fixed offset for each phase build-out event to skew the average error toward zero. this field is a two?s complement signed integer. the offset in nanoseconds is pboff[5:0] x 0.101. values greater than 1.4ns or less than -1.4ns may cause internal math errors and should not be used. see section 7.7.7.5 . register name: phlim1 register description: phase limit register 1 register address: 73h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name flen nalol 1 ? ? finelim[2:0] default 1 0 1 0 0 0 1 0 bit 7: fine phase limit enable (flen). this configuration bit enables the fine phase limit specified in the finelim[2:0] field. the fine limit must be disabled for multi-ui jitter tolerance (see phlim2 fields). this field controls both t0 and t4. see section 7.7.6 . 0 = disabled 1 = enabled bit 6: no-activity loss of lock (nalol). the t0 and t4 dplls can detect that an input clock has no activity very quickly (within two clock cycles). when nalol = 0, lo ss-of-lock is not declared when clock cycles are missing, and nearest edge locking ( 180 ) is used when the clock recovers. this gives tolerance to missing cycles. when nalol = 1, loss-of-lock is indicated as soon as no activity is detected, and the device switches to phase/frequency locking ( 360 ). this field controls both t0 and t4. see sections 7.5.3 and 7.7.6 . 0 = no activity does not trigger loss-of-lock 1 = no activity does trigger loss-of-lock bit 5: leave set to 1 (test control). bits 2 to 0: fine phase limit (finelim[2:0]). this field specifies the fine phase limit window, outside of which loss-of-lock is declared. the flen bit enables this feature. the phase of the input clock has to be inside the fine limit window for two seconds before phase lock is declared. loss-of-lock is declared imm ediately if the phase of the input clock is outside the phase limit window. the default va lue of 010 is appropriate for most situations. this field controls both t0 and t4. see section 7.7.6 . 000 = always indicates loss of phase lock?do not use 001 = small phase limit window, 45 to 90 010 = normal phase limit window, 90 to 180 (default) 100, 101, 110, 111 = proportionately larger phase limit window
DS3101 stratum 3/3e timing card ic 117 of 149 register name: phlim2 register description: phase limit register 2 register address: 74h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name clen mcpden usemcpd ? coarselim[3:0] default 1 0 0 0 0 1 0 1 bit 7: coarse phase limit enable (clen). this configuration bit enables the co arse phase limit specified in the coarselim[3:0] field. this field controls both t0 and t4. see section 7.7.6 . 0 = disabled 1 = enabled bit 6: multicycle phase detector enable (mcpden). this configuration bit enables the multicycle phase detector and allows the dpll to tolerate large-amplitude jitter and wande r. the range of this phase detector is the same as the coarse phase limit specified in the coarselim[3:0] field. this field controls both t0 and t4. see section 7.7.5 . 0 = disabled 1 = enabled bit 5: use multicycle phase detector in the dpll algorithm (usemcpd). this configuration bit enables the dpll algorithm to use the multicycle phase detector so t hat a large phase measurement dr ives faster dpll pull-in. when usemcpd = 0, phase measurement is limited to 360 , giving slower pull-in at higher frequencies but with less overshoot. when usemcpd = 1, phase measurement is set as specified in the coarselim[3:0] field, giving faster pull-in. mcpden should be set to 1 when usemcpd = 1. this field controls both t0 and t4. see section 7.7.5 . 0 = disabled 1 = enabled bits 3 to 0: coarse phase limit (coarselim[3:0]). this field specifies the coarse phase limit and the tracking range of the multicycle phase detector. the clen bit enables this feature. if jitter tolerance greater than 0.5ui is required and the input clock is a high-frequency signal, the dpll can be configured to track phase errors over many ui using the multicycle phase detector. th is field controls both t0 and t4. see section 7.7.5 and 7.7.6 . 0000 = 1ui 0001 = 3ui 0010 = 7ui 0011 = 15ui 0100 = 31ui 0101 = 63ui 0110 = 127ui 0111 = 255ui 1000 = 511ui 1001 = 1023ui 1010 = 2047ui 1011 = 4095ui 1100 to 1111 = 8191ui
DS3101 stratum 3/3e timing card ic 118 of 149 register name: phmon register description: phase monitor register register address: 76h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name nw ? pmen pmpben pmlim[3:0] default 0 0 0 0 0 1 1 0 bit 7: low-frequency input clock noise window (nw). for 2khz, 4khz, or 8khz input clocks, this configuration bit enables a 5% tolerance noise window centered around the ex pected clock edge location. noise-induced edges outside this window are ignored, reducing the possibili ty of phase hits on the output clocks. nw should be enabled only when the device is locked to an input and test1 :d180 = 0. 0 = all edges are recognized by the dpll 1 = only edges within the 5% tolerance window are recognized by the dpll bit 5: phase monitor enable (pmen). this configuration bit enables the phase monitor, which measures the phase error between the input clock reference and the dpll output. when the dpll is set for low bandwidth, a phase transient on the input causes an immediate phase error that is gradually r educed as the dpll tracks the input. when the measured phase error exceeds the limit se t in the pmlim field, the phase monitor declares a phase monitor alarm by setting msr3 :phmon. see section 7.7.7 . 0 = disabled 1 = enabled bit 4: phase monitor to phase build-out enable (pmpben). this bit enables phase build-out in response to phase hits on the selected reference. see section 7.7.7 . 0 = phase monitor alarm does not trigger a phase build-out event 1 = phase monitor alarm does trigger a phase build-out event bits 3 to 0: phase monitor limit (pmlim[3:0]). this field is an unsigned integer that specifies the magnitude of phase error that causes a phase monitor alarm to be declared (phmon bit in the msr3 register). the phase monitor limit in nanoseconds is equal to (pmlim[3:0] + 7) x 156.25, which corresponds to a range of 1094ns to 3437ns in 156.25ns steps. the phase monitor is enabled by setting pmen = 1. see section 7.7.7 .
DS3101 stratum 3/3e timing card ic 119 of 149 register name: phase1 register description: phase register 1 register address: 77h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name phase[7:0] default 0 0 0 0 0 0 0 0 the phase1 and phase2 registers must be read consecutivel y. see section 8.3 . bits 7 to 0: current dpll phase (phase[7:0]). the full 16-bit phase[15:0] field spans this register and the phase2 register. phase is a two?s-complement signed inte ger that indicates the cu rrent value of the phase detector. the value is the output of the phase averager. when t4t0 = 0 in the mcr11 register, phase indicates the current phase of the t0 dpll. when t4t0 = 1, phase indica tes the current phase of the t4 dpll. the averaged phase difference in degrees is equal to phase x 0.707. see section 7.7.10 . register name: phase2 register description: phase register 2 register address: 78h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name phase[15:8] default 0 0 0 0 0 0 0 0 bits 7 to 0: current dpll phase (phase[15:8]). see the phase1 register description. register name: phlkto register description: phase lock timeout register register address: 79h bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name phlktom[1:0] phlkto[5:0] default 0 0 1 1 0 0 1 0 bits 7 to 6: phase lock timeout multiplier (phlktom[1:0]). this field is an unsigned integer that specifies the resolution of the phase lock timeout field phlkto[5:0]. 00 = 2 seconds 01 = 4 seconds 10 = 8 seconds 11 = 16 seconds bits 5 to 0: phase lock timeout (phlkto[5:0]). this field is an unsigned integer that, together with the phlktom[1:0] field, specifies the length of time that the t0 dpll attempts to lock to an input clock before declaring a phase lock alarm (by setting the corresponding lock bit in the isr registers). the timeout period in seconds is phlkto[5:0] x 2^(phlktom[1:0]+1). the state machine remains in the pre-locked, pre-locked 2, or phase-lost modes for the specified time before declar ing a phase alarm on the selected input. see section 7.7.1 .
DS3101 stratum 3/3e timing card ic 120 of 149 register name: fscr1 register description: frame sync configuration register 1 register address: 7ah bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name 2k8ksrc ? ? ? 8kinv 8kpul 2kinv 2kpul default 0 0 0 0 0 0 0 0 bit 7: 2khz/8khz source (2k8ksrc). this configuration bit specifies the source for the 2khz and 8khz outputs available on clock outputs oc1 to oc7. see section 7.8.2.3 . 0 = t0 dpll 1 = t4 dpll bit 3: 8khz invert (8kinv). when this bit is set to 1, the 8khz signal on clock output oc10 is inverted. see section 7.8.2.5 . 0 = oc10 not inverted 1 = oc10 inverted bit 2: 8khz pulse (8kpul). when this bit is set to 1, the 8khz signal on clock output oc10 is pulsed rather than 50% duty cycle. in this mode output clock oc3 must be enabl ed, and the pulse width of oc10 is equal to the clock period of oc3. see section 7.8.2.5 . 0 = oc10 not pulsed; 50% duty cycle 1 = oc10 pulsed, with pulse width equal to oc3 period bit 1: 2khz invert (2kinv). when this bit is set to 1, the 2khz signal on clock output oc11 is inverted. see section 7.8.2.5 . 0 = oc11 not inverted 1 = oc11 inverted bit 0: 2khz pulse (2kpul). when this bit is set to 1, the 2khz signal on clock output oc11 is pulsed rather than 50% duty cycle. in this mode output clock oc3 must be enabl ed, and the pulse width of oc11 is equal to the clock period of oc3. see section 7.8.2.5 . 0 = oc11 not pulsed; 50% duty cycle 1 = oc11 pulsed, with pulse width equal to oc3 period
DS3101 stratum 3/3e timing card ic 121 of 149 register name: fscr2 register description: frame sync configuration register 2 register address: 7bh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name indep ocn ? ? ? ? phase[1:0] default 0 0 0 0 0 0 0 0 bit 7: independent frame sync and multiframe sync (indep). when this bit is set to 0, the 8khz frame sync on oc10 and the 2khz multiframe sync on oc11 are aligned wi th the other output clocks when synchronized with the sync2k input. when this bit is 1, the frame sync and mult iframe sync are independent of the other output clocks, and their edge position may change without dist urbing the other output clocks. see section 7.9.3 . 0 = oc10 and oc11 are aligned with other output clocks; all are synchronized by the sync2k input 1 = oc10 and oc11 are independent of the other cl ock outputs; only oc10 and oc11 are synchronized by the sync2k input bit 6: sync oc-n rates (ocn). see section 7.9.3 . 0 = sync2k is sampled with a 6.48mhz resolu tion; the selected reference must be 6.48mhz 1 = if the selected reference is 19.44mhz, sync2k is sampled at 19.44mhz and output alignment is to 19.44mhz. if the selected reference is 38.88mhz, sync2k is sampled at 38.88mhz. the selected reference must be either 19.44mhz or 38.88mhz bits 1 to 0: external sync sampling phase. (phase[1:0]). this field adjusts the sampling of the sync2k input. normally the falling edge of sync2k is aligned with the falling edge of the selected reference. all ui numbers listed below are ui of the sampling clock. see section 7.9.3 . 00 = coincident 01 = 0.5ui early 10 = 1 ui late 11 = 0.5ui late
DS3101 stratum 3/3e timing card ic 122 of 149 register name: fscr3 register description: frame sync configuration register 3 register address: 7ch bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name recal monlim[2:0] source[3:0] default 0 0 1 0 1 0 1 1 bit 7: phase offset recalibration (recal). when set to 1 this configuration bit causes a recalibration of the phase offset between the output clocks and the selected refe rence. this process puts the dpll into mini holdover, internally ramps the phase offset to zero, resets all clock dividers, ramps the phase offset to the value stored in the offset registers, and then switches the dpll out of mini holdover. unlike simply writing the offset registers, the recal process causes no change in the phase offset of the output clocks . recal is automatically reset to 0 when recalibration is complete. see section 7.7.8 . 0 = normal operation 1 = phase offset recalibration bits 6 to 4: sync monitor limit (monlim[2:0]). this field configures the sync monitor limit. when the external sync2k input is misaligned with respect to the oc11 out put by the specified number of resampling clock cycles then a frame sync monitor alarm is declared in the fsmon bit of the opstate register. see section 7.9.3 . 000 = 1 ui 001 = 2 ui 010 = 3 ui 011 = 4 ui 100 = 5 ui 101 = 6 ui 110 = 7 ui 111 = 8 ui bits 3 to 0: sync reference source (source[3:0]). the external sync reference may be associated with one of the input clocks. when automatic external frame sync is enabled (aefsen = 1 in the mcr3 register, the sync2k pin is only enabled when the t0 dpll is locked to the input clock specified by the source field. see section 7.9.3 . 0000 = {unused value} 0001 = ic1 0010 = ic2 0011 = ic3 0100 = ic4 0101 = ic5 0110 = ic6 0111 = ic7 1000 = ic8 1001 = ic9 1010 = ic10 1011 = ic11 1100 = ic12 1101 = ic13 1110 = ic14 1111 = {unused value}
DS3101 stratum 3/3e timing card ic 123 of 149 register name: intcr register description: interrupt configuration register register address: 7dh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? ? ? ? ? gpo od pol default 0 0 0 0 0 0 1 0 bit 2: intreq pin general pu rpose output enable (gpo). when set to 1 this bit configures the interrupt request pin to be a general purpose output whose value is set by the pol bit. 0 = intreq is used for interrupts 1 = intreq is a general purpose output bit 1: intreq pin open drain enable (od). when gpo = 0: 0 = intreq is driven in both inactive and active states 1 = intreq is open-drain, i.e., it is driven in the active state but is high impedance in the inactive state when gpo = 1: 0 = intreq is driven as specified by pol 1 = intreq is high impedance and pol has no effect bit 0: intreq pin polarity (pol). when gpo = 0: 0 = intreq goes low to signal an interrupt (active low) 1 = intreq goes high to signal an interrupt (active high) when gpo = 1: 0 = intreq driven low 1 = intreq driven high register name: prot register description: protection register register address: 7eh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name prot[7:0] default 1 0 0 0 0 1 0 1 bits 7 to 0: protection control (prot[7:0]). this field can be used to protect the rest of the register set from inadvertent writes. in protected mode writes to all other registers are ignored. in single unprotected mode, one register (other than prot) can be written, but after that write the device reverts to protected mode (and the value of prot is internally changed to 00h). in fully unprotecte d mode all register can be written without limitation. see section 7.2 . 1000 0101 = fully unprotected mode 1000 0110 = single unprotected mode all other values = protected mode
DS3101 stratum 3/3e timing card ic 124 of 149 register name: ifcr register description: microprocessor interface configuration register register address: 7fh bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 name ? ? ? ? ? ifsel[2:0] default 0 0 0 0 0 reset value of ifsel[2:0] pins bits 2:0 microprocessor interface selection (ifsel[2:0]). this read-only field specifies the microprocessor interface mode. the value of this register is latched from the ifsel[2:0] pins during reset. after reset the state of the ifsel[2:0] pins has no effect on this register but is shown in the ifsr register. see section 7.11 . 010 = intel bus mode (multiplexed) 011 = intel bus mode (nonmultiplexed) 100 = motorola mode (nonmultiplexed) 101 = spi mode (address and data transmitted lsb first) 110 = motorola mode (multiplexed) 111 = spi mode (address and data transmitted msb first) 000, 001 = {unused value}
DS3101 stratum 3/3e timing card ic 125 of 149 9. jtag test access po rt and boundary scan 9.1 jtag description the DS3101 supports the standard instruction codes sample/prel oad, bypass, and extest. optional public instructions included are highz, clamp, and idcode. figure 9-1 shows a block diagram. the DS3101 contains the following items, which meet the requirements set by the ieee 1149.1 standard test access port and boundary scan architecture: test access port (tap) bypass register tap controller boundary scan register instruction register device identification register the tap has the necessary interface pins, namely jtclk, jtrst , jtdi, jtdo, and jtms. details on these pins can be found in table 6-6 . details about the bo undary scan architecture and the tap can be found in ieee 1149.1- 1990, ieee 1149.1a-1993, and ieee 1149.1b-1994. figure 9-1. jtag block diagram boundary scan register device identification register bypass register instruction register test access port controller mux select tri-state jtdi 50k jtms 50k jtclk j trs t 50k jtdo
DS3101 stratum 3/3e timing card ic 126 of 149 9.2 jtag tap controller state machine description this section discusses the operation of the tap controlle r state machine. the tap controller is a finite state machine that responds to the logic level at jtms on t he rising edge of jtclk. each of the states denoted in figure 9-2 are described in the following paragraphs. test-logic-reset. upon device power-up, the tap controller starts in the test-logic-reset state. the instruction register contains the idcode in struction. all system logic on the device operates normally. run-test-idle. run-test-idle is used between scan operations or dur ing specific tests. the instruction register and all test registers remain idle. select-dr-scan. all test registers retain their pr evious state. with jtms low, a rising edge of jtclk moves the controller into the capture-dr state and initiates a scan sequence. jtms high moves the controller to the select- ir-scan state. capture-dr. data can be parallel-loaded into the test register se lected by the current instru ction. if the instruction does not call for a parallel load or the selected test register does not allow parallel loads, the register remains at its current value. on the rising edge of jtclk, the controller goe s to the shift-dr state if jtms is low or to the exit1- dr state if jtms is high. shift-dr. the test register selected by the current instru ction is connected between jtdi and jtdo and data is shifted one stage toward the serial output on each rising edge of jtclk. if a test register selected by the current instruction is not placed in the serial path, it maintains it s previous state. exit1-dr. while in this state, a rising edge on jtclk with jtms high puts the controller in the update-dr state, which terminates the scanning process. a rising edge on jtclk with jtms low puts the controller in the pause-dr state. pause-dr. shifting of the test registers is halted while in this state. all test register s selected by the current instruction retain their previous state. the controller re mains in this state while jtms is low. a rising edge on jtclk with jtms high puts the cont roller in the exit2-dr state. exit2-dr. while in this state, a rising edge on jtclk with jtms high puts the controller in the update-dr state and terminates the scanning process. a rising edge on jtclk with jtms low puts the controller in the shift-dr state. update-dr. a falling edge on jtclk while in the update-dr state latches the data from the shift register path of the test registers into the data output latches. this pr events changes at the parallel output because of changes in the shift register. a rising edge on jtclk with jtms low put s the controller in the run-test-idle state. with jtms high, the controller enters t he select-dr-scan state. select-ir-scan. all test registers retain their pr evious state. the instruction regi ster remains unchanged during this state. with jtms low, a rising edge on jtclk moves the c ontroller into the capture-ir state and initiates a scan sequence for the instruction register. jtms high duri ng a rising edge on jtclk puts the controller back into the test-logic-reset state. capture-ir. the capture-ir state is used to load the shift register in the instruction register with a fixed value. this value is loaded on the rising edge of jtclk. if jtms is high on the rising edge of jt clk, the controller enters the exit1-ir state. if jtms is low on the rising edge of jtclk, the controller enters the shift-ir state. shift-ir. in this state, the instruction register?s shift regist er is connected between jtdi and jtdo and shifts data one stage for every rising edge of jtclk toward the serial output. the parallel register and the test registers remain at their previous states. a rising edge on jtclk wi th jtms high moves the controller to the exit1-ir state. a rising edge on jtclk with jtms low keeps the controlle r in the shift-ir state, while moving data one stage through the instruction shift register. exit1-ir. a rising edge on jtclk with jtms low puts the controll er in the pause-ir state. if jtms is high on the rising edge of jtclk, the controller enters the u pdate-ir state and terminates the scanning process.
DS3101 stratum 3/3e timing card ic 127 of 149 pause-ir. shifting of the instruction register is halted tempor arily. with jtms high, a rising edge on jtclk puts the controller in the exit2-ir state. t he controller remains in the pause-ir st ate if jtms is low during a rising edge on jtclk. exit2-ir. a rising edge on jtclk with jtms high puts the cont roller in the update-ir st ate. the controller loops back to the shift-ir state if jtms is low during a rising edge of jtclk in this state. update-ir. the instruction shifted into the instruction shift regi ster is latched into the parallel output on the falling edge of jtclk as the controller enters this state. once latched, this instructio n becomes the current instruction. a rising edge on jtclk with jtms low puts the controller in the run-test-idle state. wi th jtms high, the controller enters the select-dr-scan state. figure 9-2. jtag tap controller state machine test-logic-reset run-test/idle select dr-scan 1 0 capture-dr 1 0 shift-dr 0 1 exit1- dr 1 0 pause-dr 1 exit2-dr 1 update-dr 0 0 1 select ir-scan 1 0 capture-ir 0 shift-ir 0 1 exit1-ir 1 0 pause-ir 1 exit2-ir 1 update-ir 0 0 1 0 0 1 0 1 0 1
DS3101 stratum 3/3e timing card ic 128 of 149 9.3 jtag instruction regi ster and instructions the instruction register contains a shift register as well as a latched parallel output and is 3 bits in length. when the tap controller enters the shift-ir state, the instruction sh ift register is connected between jtdi and jtdo. while in the shift-ir state, a rising edge on jtclk with jtms low shifts data one stage toward t he serial output at jtdo. a rising edge on jtclk in the exit1-ir state or the exit2-ir state with jtms high move s the controller to the update- ir state. the falling edge of that same jtclk latches the dat a in the instruction shift register to the instruction parallel output. table 9-1 shows the instructions suppor ted by the DS3101 and their respective operational binary codes. table 9-1. jtag instruction codes instructions selected register instruction codes sample/preload boundary scan 010 bypass bypass 111 extest boundary scan 000 clamp bypass 011 highz bypass 100 idcode device identification 001 sample/preload. sample/reload is a mandatory instruction for the ieee 1149.1 sp ecification. this instruction supports two functions. first, the digital i/o s of the device can be sampled at the boundary scan register, using the capture-dr state, without interfering with the device?s nor mal operation. second, data can be shifted into the boundary scan register th rough jtdi using the shift-dr state. extest. extest allows testing of the interconnections to t he device. when the extest instruction is latched in the instruction register, the following actions occur: (1) once the extest instruction is enabled through the update-ir state, the parallel outputs of the digital output pins are driven. (2) the boundary scan register is connected between jtdi and jtdo. (3) the capture-dr state samples all digital inputs into the boundary scan register. bypass. when the bypass instruction is latched into the parallel instruction register, jtdi is connected to jtdo through the 1-bit bypass register. this allows data to pass from jtdi to jtdo without affecting the device?s normal operation. idcode. when the idcode instruction is latched into the para llel instruction register, the device identification register is selected. the device id code is loaded into t he device identification register on the rising edge of jtclk, following entry into the capture-dr state. shift-dr can be used to shift the id code out serially through jtdo. during test-logic-reset, the id code is forced in to the instruction register?s parallel output. highz. all digital outputs are placed into a high-impedance st ate. the bypass register is connected between jtdi and jtdo. clamp. all digital output pins output data from the bounda ry scan parallel output while connecting the bypass register between jtdi and jtdo. the outputs do not change during the clamp instruction.
DS3101 stratum 3/3e timing card ic 129 of 149 9.4 jtag test registers ieee 1149.1 requires a minimum of two test registers?t he bypass register and the boundary scan register. an optional test register, the identificati on register, has been included in the device design. it is used with the idcode instruction and the test-logic-res et state of the tap controller. bypass register. this is a single 1-bit shift register used wi th the bypass, clamp, and hi ghz instructions to provide a short path between jtdi and jtdo. boundary scan register. this register contains a shift register path and a latched parallel output for control cells and digital i/o cells. bsdl files are available at www.maxim-ic.com/techsupport/telecom/bsdl.htm . identification register. this register contains a 32-bit shift regist er and a 32-bit latched parallel output. it is selected during the idcode instruction and when the tap c ontroller is in the test-logic-reset state. the device identification code for the DS3101 is shown in table 9-2. table 9-2. jtag id code device revision device code manufacturer code required DS3101 consult factory 0000000000011101 00010100001 1
DS3101 stratum 3/3e timing card ic 130 of 149 10. electrical characteristics absolute maximum ratings voltage range on any pin with respect to v ss (except v dd )??.???????????????..-0.3v to +5.5v supply voltage range (v dd ) with respect to v ss ??.????.???????????????..-0.3v to +1.98v supply voltage range (v ddio ) with respect to v ss ?????.????????????????.-0.3v to +3.63v ambient operating temperature range ??????????????????????????.-40c to +85c junction operating temperature range?????????????????????????..-40c to +125c storage temperature range??????????????????????????????..-55c to +125c soldering temperature??????????????????????s ee ipc/jedec j-std-020 specification stresses beyond those listed under ?absolute maximum ratings? may c ause permanent damage to the device. these are stress rating s only, and functional operation of the device at t hese or any other conditions beyond those indicated in the operational sections of t he specifications is not implied. exposure to the absolute ma ximum rating conditions for ex tended periods may affect device. ambient operating tempe rature range when device is mounted on a four-layer jedec test board with no airflow. note: the typical values listed in the tables of section 10 are not production tested. 10.1 dc characteristics table 10-1. recommended dc operating conditions (t a = -40c to +85c) parameter symbol conditions min typ max units supply voltage, core v dd 1.62 1.8 1.98 v supply voltage, i/o v ddio 3.135 3.3 3.465 v ambient temperature range t a -40 +85 c table 10-2. dc characteristics (v dd = 1.8v 10%, v ddio = 3.3v 5%, t a = -40c to +85c.) parameter symbol conditions min typ max units 1.8v i dd18 (note 1) 100 120 supply current 3.3v i dd33 (note 1) 37 53 ma supply current from vdd_oc6 when output oc6 is enabled i ddoc6 (note 2) 9 ma supply current from vdd_oc7 when output oc7 is enabled i ddoc7 (note 2) 9 ma input capacitance c in 5 pf output capacitance c out 7 pf note 1: 12.800mhz clock applied to refclk. 19.44mhz clock applied to one cmos/ttl input clock pin. one 19.44mhz cmos/ttl output clock pin driving 100pf load; all other inputs at v ddio or grounded; all other outputs open. note 2: 19.44mhz output clock frequency, driving the load shown in figure 10-1 .
DS3101 stratum 3/3e timing card ic 131 of 149 table 10-3. cmos/ttl pins (v dd = 1.8v 10%, v ddio = 3.3v 5%, t a = -40c to +85c.) parameter symbol conditions min typ max units input high voltage v ih 2.0 5.5 v input low voltage v il -0.3 +0.8 v input leakage i il (note 1) -10 +10 a input leakage, pins with internal pullup resistor (50k typical) i ilpu (note 1) -85 +10 a input leakage, pins with internal pulldown resistor (50k typical) i ilpd (note 1) -10 +85 a output leakage (when high-z) i lo (note 1) -10 +10 a output high voltage (i o = -4.0ma) v oh 2.4 v ddio v output low voltage (i o = +4.0ma) v ol 0 0.4 v note 1: 0v < v in < v ddio for all other digital inputs. table 10-4. lvds pins (v dd = 1.8v 10%, v ddio = 3.3v 5%, t a = -40c to +85c.) (see figure 10-1 .) parameter symbol conditions min typ max units input voltage range v inlvds v idlvds = 100mv 0 2.4 v differential input voltage v idlvds 0.1 1.4 v differential input logic threshold v thlvds -100 +100 mv output high voltage v ohlvds (note 1) 1.45 1.65 v output low voltage v ollvds (note 1) 0.885 1.1 v differential output voltage v odlvds 250 450 mv output offset voltage v oslvds +25 c (note 1) 1.08 1.28 1.45 v difference in magnitude of output differential voltage for complementary states v doslvds 25 mv note 1: with 100 load across the differential outputs. note 2: the DS3101?s lvds output pins can easily be interfaced to lvpecl and cml inputs on neighboring ics using a few external passive components. refer to maxim app note hfan-1.0 for details. figure 10-1. recommended termination for lvds pins input signal pos input signal neg input pos input neg 100 (5%) 50 50 output pos output neg 50 50 output signal pos output signal neg 100 (5%)
DS3101 stratum 3/3e timing card ic 132 of 149 table 10-5. lvpecl pins (v dd = 1.8v 10%, v ddio = 3.3v 5%, t a = -40c to +85c) (see figure 10-2 .) parameter symbol conditions min typ max units input high voltage, differential inputs v ihpecl (note 1) v ddio - 2.4 v ddio - 0.4 v input low voltage, differential inputs v ilpecl (note 1) v ddio - 2.5 v ddio - 0.5 v input differential voltage v idpecl 0.1 1.4 v input high voltage, single-ended inputs v ihpecl,s (note 2) v ddio - 1.3 v ddio - 0.5 v input low voltage, single-ended inputs v ilpecl,s (note 2) v ddio - 2.4 v ddio - 1.5 v note 1: for a differential input voltage 100mv. note 2: with the unused differential input tied to v ddio - 1.4v. note 3: although the DS3101?s differential outputs do not directly driv e standard lvpecl signals, these output pins can easily be interfaced to lvpecl and cml inputs on neighboring ics using a few external passive components. refer to maxim app note hfan-1.0 for details. figure 10-2. recommended termination for lvpecl pins input signal pos input signal neg input pos input neg 1 30 1 30 8 2 8 2 5 0 5 0 vss_icdiff vdd_icdiff
DS3101 stratum 3/3e timing card ic 133 of 149 table 10-6. ami composite clock pins (v dd = 1.8v 10%, v ddio = 3.3v 5%, t a = -40c to +85c.) (note 1) (see figure 10-3 .) parameter symbol conditions min typ max unit s input high voltage v ihami 2.2 v ddio + 0.3 v input middle voltage v imami 1.5 1.65 1.8 v input low voltage v ilami -0.3 1.1 v input los threshold v los at the ic1/ic2 pin 0.2 v input pulse width t pw 1.6 7.8 14 s input rise/fall time t r , t f 0.5 s note 1: the timing parameters in this table are guaranteed by design (gbd). figure 10-3. recommended external com ponents for ami composite clock pins input signal ic1 ic2 oc8pos oc8neg output signal pos output signal neg 470 nf 470 nf input signal 0.01uf r p r s r s 1:1 for input cc signals compliant with telcordia gr-378 (amp litude 2.7v to 5.5v) or it u g.703 section 4.2.2 option b) (3v 0.5v), the signal should be attenuated by a factor of 3 (or more) before being pres ented to ic1a or ic2a. input cc signals with a 1v nominal pu lse amplitude can be presented unattenuated. for output cc signals, table 10-7 specifies recommended values for the components in figure 10-3 . recommended transformers include the pe-65540 from pulse engineering. table 10-7. recommended external components for output clock oc8 signal type r s r p gr-378 (133 , 2.7v?5.5v) 0 open g.703 4.2.2 option b) (110 , 3v 0.5v) 0 open g.703 4.2.2 option a) and appendix ii.1 (110 , 1v 0.1v) 91 360 g.703 4.2.3 (120 , 1v 0.1v) 91 300
DS3101 stratum 3/3e timing card ic 134 of 149 10.2 input clock timing table 10-8. input clock timing (v dd = 1.8v 10%, v ddio = 3.3v 5%, t a = -40c to +85c.) parameter symbol min typ max input clock period, cmos/ttl input pins t cyc 8ns (125mhz) 500 s (2khz) input clock period, lvds/lvpecl input pins t cyc 6.43ns (155.52mhz) 500 s (2khz) input clock high, low time t h , t l 3ns or 30% of t cyc , whichever is smaller 10.3 output clock timing table 10-9. input clock to output clock delay input frequency output frequency delay, input clock edge to output clock edge 8khz 8khz 0.0 1.5ns 6.48mhz 6.48mhz -12 1.5ns 19.44mhz 19.44mhz 0.0 1.5ns 25.92mhz 25.92mhz 0.0 1.5ns 38.88mhz 38.88mhz 0.0 1.5ns 51.84mhz 51.84mhz 0.0 1.5ns 77.76mhz 77.76mhz 0.0 1.5ns 155.52mhz 155.52mhz 0.0 1.5ns table 10-10. output clo ck phase alignment, frame sync alignment mode output frequency delay, oc1 (2khz) falling edge to output clock falling edge 8khz (oc10) 0.0 0.5ns 2khz 0.0 0.5ns 8khz 0.0 0.5ns 1.544mhz (oc9) 0.0 1.25ns 2.048mhz (oc9) 0.0 1.25ns 44.736mhz -2.0 1.25ns 34.368mhz -2.0 1.25ns 6.48mhz -2.0 1.25ns 19.44mhz -2.0 1.25ns 25.92mhz -2.0 1.25ns 38.88mhz -2.0 1.25ns 51.84mhz -2.0 1.25ns 77.76mhz -2.0 1.25ns 155.52mhz -2.0 1.25ns 311.04mhz -2.0 1.25ns see section 7.9.3 for details on frame sync alignment and the sync2k pin.
DS3101 stratum 3/3e timing card ic 135 of 149 10.4 parallel interface timing table 10-11. parallel interface timing (v dd = 1.8v 10%, v ddio = 3.3v 5%, t a = -40c to +85c.) (note 1) (see figure 10-4 and figure 10-5 .) parameter symbol conditions min typ max units address setup to rd , wr , ds active t1a (note 2) 10 ns ale setup to rd , wr , ds active t1b (notes 2, 3) 10 ns address setup to ale inactive t2 (notes 2, 3) 2 ns address hold from ale inactive t3 (notes 2, 3) 2 ns ale pulse width t4 (notes 2, 3) 5 ns address hold from rd , wr , ds inactive t5 (note 2) 0 ns cs setup to rd , wr , ds active t6 (note 2) 0 ns data valid from rd , ds active t8 (note 2) 80 ns rd , wr , ds pulse width if not using rdy handshake t9a (notes 2, 4) 90 ns rd , wr , ds delay from rdy active t9b (note 2) 15 ns data output high-z from rd , ds inactive t10 (notes 2, 5) 2 10 ns data output enabled from rd , ds active t11 (note 2) 2 ns cs hold from rd , wr , ds inactive t12 (note 2) 0 ns data setup to wr , ds inactive t13 (note 2) 10 ns data hold from wr , ds inactive t14 (note 2) 5 ns rdy active from rd , wr , ds active t15 (note 2) 10 ns rdy inactive from rd , wr , ds inactive t16 (note 2) 0 10 ns rdy output enabled from cs active t17 (note 2) 10 ns rdy output high-z from cs inactive t18 (note 2) 10 ns rdy ending high pulse width t19 (note 2) 2 ns r/ w setup to ds active t20 (note 2) 2 ns r/ w hold from ds inactive t21 (note 2) 2 ns note 1: the timing parameters in this table are guaranteed by design (gbd). note 2: the input/output timing reference level for all signals is vdd/2. transition time (80/20%) on rd , wr, and cs inputs is 5ns max. note 3: multiplexed mode timing only. note 4: timing required if not using rdy handshake. note 5: d[7:0] output valid until not driven.
DS3101 stratum 3/3e timing card ic 136 of 149 figure 10-4. parallel interface ti ming diagram (nonmultiplexed) data out ad[7:0] r d y t8 t10 cs t6 t12 rd wr ds t9a address t5 t1a data in ad[7:0] t13 t14 t15 t16 t17 t18 t19 r/ w t20 t21 t9b t11
DS3101 stratum 3/3e timing card ic 137 of 149 figure 10-5. parallel interface timing diagram (multiplexed) data out ad[7:0] r d y t8 t10 cs t6 t12 rd wr ds t9a data in ad[7:0] t13 t14 t15 t16 t17 t18 t19 r/ w t20 t21 address t1a ale t2 t3 t4 t1b t9b t5 t11
DS3101 stratum 3/3e timing card ic 138 of 149 10.5 spi interface timing table 10-12. spi interface timing (v dd = 1.8v 10%, v ddio = 3.3v 5%, t a = -40c to +85c.) (note 1) (see figure 10-6 .) parameter (note 2) symbol min typ max units sclk frequency f bus 6 mhz sclk cycle time t cyc 100 ns cs setup to first sclk edge t suc 15 ns cs hold time after last sclk edge t hdc 15 ns sclk high time t clkh 50 ns sclk low time t clkl 50 ns sdi data setup time t sui 5 ns sdi data hold time t hdi 15 ns sdo enable time (high-impedance to output active) t en 0 ns sdo disable time (output active to high impedance) t dis 25 ns sdo data valid time t dv 40 ns sdo data hold time after update sclk edge t hdo 5 ns note 1: the timing parameters in this table are guaranteed by design (gbd). note 2: all timing is specified with 100pf load on all spi pins. figure 10-6. spi interface timing diagram cs sclk, cpol=0 sclk, cpol=1 t sui t hdi sdi t cyc t suc t clkh t clkl t clkl t clkh t hdc sdo t en t dv t hdo t dis cpha = 0 cpha = 1 cs sclk, cpol=0 sclk, cpol=1 t cyc t suc t clkh t clkl t clkl t hdc t sui t hdi sdi sdo t en t dv t hdo t dis t clkh
DS3101 stratum 3/3e timing card ic 139 of 149 10.6 jtag interface timing table 10-13. jtag interface timing (v dd = 1.8v 10%, v ddio = 3.3v 5%, t a = -40c to +85c.) (note 1) (see figure 10-7 .) parameter symbol min typ max units jtclk clock period t1 1000 ns jtclk clock high/low time (note 2) t2/t3 50 500 ns jtclk to jtdi, jtms setup time t4 50 ns jtclk to jtdi, jtms hold time t5 50 ns jtclk to jtdo delay t6 2 50 ns jtclk to jtdo high-z delay (note 3) t7 2 50 ns jtrst width low time t8 100 ns note 1: the timing parameters in this table are guaranteed by design (gbd). note 2: clock can be stopped high or low. note 3: not tested during production test. figure 10-7. jtag timing diagram t1 jtdo t4 t5 t2 t3 t7 jtdi, jtms, j trs t t6 jtrst t8 jtcl k
DS3101 stratum 3/3e timing card ic 140 of 149 11. pin assignments table 11-1 lists the DS3101 pin assignments sorted in alphabetical order by pin name. figure 11-1 and figure 11-2 show pin assignments arranged by pin number. table 11-1. pin assignments sorted by signal name pin name pin number bus modes signal type a[0] h16 parallel-only high-speed digital a[1] h15 parallel-only high-speed digital a[2] g16 parallel-only high-speed digital a[3] h14 parallel-only high-speed digital a[4] g15 parallel-only high-speed digital a[5] f16 parallel-only high-speed digital a[6] g14 parallel-only high-speed digital a[7] f15 parallel-only high-speed digital a[8] e16 parallel-only high-speed digital ad[0] e15 parallel-only high-speed digital ad[1] d16 parallel-only high-speed digital ad[2] c16 parallel-only high-speed digital ad[3] d15 parallel-only high-speed digital ad[4] c15 parallel-only high-speed digital ad[5] e14 parallel-only high-speed digital ad[6] d14 parallel-only high-speed digital ad[7] c14 parallel-only high-speed digital ale k14 parallel-only high-speed digital avdd_pll1 d1 all power supply avdd_pll2 e1 all power supply avdd_pll3 f1 all power supply avdd_pll4 g1 all power supply avss_pll1 d2 all power supply avss_pll2 e3 all power supply avss_pll3 g2 all power supply avss_pll4 g3 all power supply cpha d14 spi-only low-speed digital cpol c14 spi-only low-speed digital cs j16 all high-speed digital ds j14 parallel-only high-speed digital gpio1 e2 all low-speed digital gpio2 f3 all low-speed digital gpio3 h2 all low-speed digital gpio4 j1 all low-speed digital hiz r14 all low-speed digital ic1 a10 all high-speed digital ic10 b12 all high-speed digital ic11 a13 all high-speed digital ic12 c12 all high-speed digital ic13 b13 all high-speed digital ic14 a14 all high-speed digital
DS3101 stratum 3/3e timing card ic 141 of 149 pin name pin number bus modes signal type ic1a p6 all low-speed analog ic2 b10 all high-speed digital ic2a p7 all low-speed analog ic3 c10 all high-speed digital ic4 a11 all high-speed digital ic5neg a5 all high-speed analog ic5pos b5 all high-speed analog ic6neg a4 all high-speed analog ic6pos b4 all high-speed analog ic7 b11 all high-speed digital ic8 c11 all high-speed digital ic9 a12 all high-speed digital ifsel[0] n1 all low-speed digital ifsel[1] n2 all low-speed digital ifsel[2] p1 all low-speed digital intreq a15 all low-speed digital jtclk r8 all low-speed digital jtdi r9 all low-speed digital jtdo p9 all low-speed digital jtms t9 all low-speed digital jtrst t8 all low-speed digital mastslv r11 all low-speed digital n.c. c13, f2, f14, j3, k1, k2, k3, k15, k16, l1, l2, l3, l14, l15, l16, m1, m14, m15, m16, n14, n15, n16, p2, p3, p4, p5, p8, p12, p13, p14, p15, p16, r2, r3, r4, r5, r6, r7, r13, r15, t2, t3, t4, t5, t6, t7, t15 all no connection oc1 c6 all high-speed digital oc10 b9 all low-speed digital oc11 c9 all low-speed digital oc2 a7 all high-speed digital oc3 b7 all high-speed digital oc4 c7 all high-speed digital oc5 a8 all high-speed digital oc6neg a3 all high-speed analog oc6pos b3 all high-speed analog oc7neg c1 all high-speed analog oc7pos c2 all high-speed analog oc8neg b8 all low-speed analog oc8pos c8 all low-speed analog oc9 a9 all low-speed digital r/ w j15 parallel-only high-speed digital rd j14 parallel-only high-speed digital rdy b15 parallel-only high-speed digital refclk h1 all low-speed digital rst b6 all low-speed digital
DS3101 stratum 3/3e timing card ic 142 of 149 pin name pin number bus modes signal type sclk c16 spi-only low-speed digital sdi d16 spi-only low-speed digital sdo e15 spi-only low-speed digital sonsdh m3 all low-speed digital srcsw m2 all low-speed digital srfail j2 all low-speed digital sync2k b14 all low-speed digital tm1 r13 all test, wire low tm2 t15 all test, wire low tst_ra1 r6 all test, do not connect tst_ra2 l14 all test, do not connect tst_rb1 t6 all test, do not connect tst_rb2 k16 all test, do not connect tst_rc1 r7 all test, do not connect tst_rc2 k15 all test, do not connect tst_ta1 p2 all test, do not connect tst_ta2 r15 all test, do not connect tst_tb1 n3 all test, do not connect tst_tb2 p13 all test, do not connect tst_tc1 p3 all test, do not connect tst_tc2 p14 all test, do not connect v dd d6, d8, d9, d11, e6, e11, f4, f5, f12, f13, h4, h13, j4, j13, l4, l5, l12, l13, m6, m11, n6, n8, n9, n11 all power supply vdd_icdiff a6 all power supply vdd_oc6 b2 all power supply vdd_oc7 c3 all power supply v ddio b1, b16, d7, d10, e7?e10, g4, g5, g12, g13, h5, h12, j5, j12, k4, k5, k12, k13, m7, m8, m9, m10, n7, n10, r1, r16 all power supply v ss a1, a16, d4, d5, d12, d13, e4, e5, e12, e13, f6?f11, g6?g11, h6?h11, j6?j11, k6?k11, l6?l11, m4, m5, m12, m13, n4, n5, n12, n13, t1, t16 all power supply vss_icdiff c4 all power supply vss_oc6 a2 all power supply vss_oc7 d3 all power supply wdt c5 all low-speed analog wr j15 parallel-only high-speed digital
DS3101 stratum 3/3e timing card ic 143 of 149 figure 11-1. DS3101 pin assignment?left half 1 2 3 4 5 6 7 8 a v ss vss_oc6 oc6neg ic6neg ic5neg vdd_icdiff oc2 oc5 b v ddio vdd_oc6 oc6pos ic6pos ic5pos rst oc3 oc8neg c oc7neg oc7pos vdd_oc7 vss_icdiff wdt oc1 oc4 oc8pos d avdd_pll1 avss_pll1 vss_oc7 v ss v ss v dd v ddio v dd e avdd_pll2 gpio1 avss_pll2 v ss v ss v dd v ddio v ddio f avdd_pll3 n.c. gpio2 v dd v dd v ss v ss v ss g avdd_pll4 avss_pll3 avss_pll4 v ddio v ddio v ss v ss v ss h refclk gpio3 n.c. v dd v ddio v ss v ss v ss j gpio4 srfail n.c. v dd v ddio v ss v ss v ss k n.c. n.c. n.c. v ddio v ddio v ss v ss v ss l n.c. n.c. n.c. v dd v dd v ss v ss v ss m n.c. srcsw sonsdh v ss v ss v dd v ddio v ddio n ifsel[0] ifsel[1] n.c. v ss v ss v dd v ddio v dd p ifsel[2] n.c. n.c. n.c. n.c. ic1a ic2a n.c. r v ddio n.c. n.c. n.c. n.c. n.c. n.c. jtclk t v ss n.c. n.c. n.c. n.c. n.c. n.c. jtrst 1 2 3 4 5 6 7 8 high-speed analog low-speed analog high-speed digital low-speed digital v dd 3.3v analog v dd 3.3v v dd 1.8v analog v dd 1.8v v ss analog v ss n.c. = no connection. lead is not co nnected to anything inside the device.
DS3101 stratum 3/3e timing card ic 144 of 149 figure 11-2. DS3101 pin a ssignment?right half 9 10 11 12 13 14 15 16 oc9 ic1 ic4 ic9 ic11 ic14 intreq vss a oc10 ic2 ic7 ic10 ic13 sync2k rdy vddio b oc11 ic3 ic8 ic12 n.c. ad[7]/cpol ad[4] ad[2]/sclk c v dd v ddio v dd v ss v ss ad[6]/cpha ad[3] ad[1] / sdi d v ddio v ddio v dd v ss v ss ad[5] ad[0]/sdo a[8] e v ss v ss v ss v dd v dd n.c. a[7] a[5] f v ss v ss v ss v ddio v ddio a[6] a[4] a[2] g v ss v ss v ss v ddio v dd a[3] a[1] a[0] h v ss v ss v ss v ddio v dd rd / ds wr /r /w cs j v ss v ss v ss v ddio v ddio ale n.c. n.c. k v ss v ss v ss v dd v dd n.c. n.c. n.c. l v ddio v ddio v dd v ss v ss n.c. n.c. n.c. m v dd v ddio v dd v ss v ss n.c. n.c. n.c. n jtdo n.c. n.c. n.c. n.c. n.c. n.c. n.c. p jtdi n.c. mastslv n.c. tm1 hiz n.c. v ddio r jtms n.c. n.c. n.c. n.c. n.c. tm2 v ss t 9 10 11 12 13 14 15 16 high-speed analog low-speed analog high-speed digital low-speed digital v dd 3.3v analog v dd 3.3v v dd 1.8v analog v dd 1.8v v ss analog v ss n.c. = no connection. lead is not co nnected to anything inside the device.
DS3101 stratum 3/3e timing card ic 145 of 149 12. package information (the package drawing(s) in this data sheet may not reflect the most current specifications. the package number provided for each package is a link to the latest package outline information.) 12.1 256-pin csbga (17mm x 17mm) ( 56-g6017-001 )
DS3101 stratum 3/3e timing card ic 146 of 149 13. thermal information table 13-1. thermal propert ies, natural convection parameter min typ max units ambient temperature (note 1) -40 +85 c junction temperature -40 +125 c theta - ja ( ja ), still air (note 2) 26.7 c/w theta - jb ( jb ), still air 14.0 c/w theta - jc ( jc ), still air 11.0 c/w psi-jb 13.5 c/w psi-jt 0.7 c/w note 1: the package is mounted on a four - layer jedec standard test board with no airflow and dissipating maximum power. note 2: theta - ja ( ja ) is the junction to ambient thermal resistance, when the package is mounted on a four - layer jedec standard test board with no airflow and dissipating maximum power.
DS3101 stratum 3/3e timing card ic 147 of 149 14. glossary local oscillator the 12.800mhz tcxo, ocxo, or other crysta l oscillator connected to the refclk pin. the stability of the t0 dpll in free-run and holdo ver modes is a function of the stability of this oscillator. master clock a 204.8mhz clock synthesized from the local oscillator and frequency adjusted by the xofreq register setting. input clock one of the 14 input clocks labeled ic1 to ic14. output clock one of the 11 output clocks labeled oc1 to oc11. selected reference the input clock to which the dpll is currently phase locked. valid clock an input clock that has no alarms declared in the corresponding isr register. a clock whose frequency is within the hard limit set in ilimit or climit and that does not have an inactivity alarm. invalid clock an input clock that has one or more alarms declared in the corresponding isr register. external reference switching mode extsw = 1 in mcr10 .
DS3101 stratum 3/3e timing card ic 148 of 149 15. acronyms a nd abbreviations ais alarm indication signal ami alternate mark inversion apll analog phase-locked loop bits building integrated timing supply bpv bipolar violation dfs digital frequency synthesis dpll digital phase locked loop esf extended superframe exz excessive zeros gbe gigabit ethernet i/o input/output los loss of signal lvds low-voltage-differential signal lvpecl low-voltage positive emitter-coupled logic mtie maximum time interval error ocxo oven-controlled crystal oscillator oof out-of-frame alignment pbo phase build-out pfd phase/frequency detector pll phase-locked loop ppb parts per billion ppm parts per million pk-pk peak-to-peak rms root-mean-square rai remote alarm indication ro read-only r/w read/write sdh synchronous digital hierarchy sec sdh equipment clock sets synchronous equipment timing source sf superframe sonet synchronous optical network ssm synchronization status message ssu synchronization supply unit stm synchronous transport module tdev time deviation tcxo temperature-compen sated crystal oscillator ui unit interval ui p-p unit interval, peak to peak 16. trademark acknowledgements spi is a trademark of motorola, inc. telcordia is a registered trademark of telcordia technologies
DS3101 stratum 3/3e timing card ic 149 of 149 maxim/dallas semiconductor cannot assume res ponsibility for use of any circuitry other than circuitry entirely embodied in a ma xim/dallas semiconductor product. no circuit patent licenses are implied. maxi m/dallas semiconductor reserves the right to change the circuitry and specification s without notice at any time. maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 ? 2007 maxim integrated products the maxim logo is a registered trademark of maxim integrated produ cts, inc. the dallas logo is a registered trademark of dallas semiconductor corporation. 17. data sheet re vision history revision description 101706 initial release. 061307 (page 1) in the feature bullets , changed ?g.812 types i and iii? to ?g.812 types i, iii, and iv.? (page 1) updated spec name from g.pactiming to g.8261. (page 6) in table 1-1 , deleted reference to ieee 1596.3 standard. (page 8) updated figure 3-1 to show backplane traces going between timing cards. (page 20) edited section 7.4 to indicate minimum high time or low time is 3ns or 30% of clock period, whichever is smaller. (page 21) in table 7-2 , added indications that ic5 and ic6 can be cmos/ttl inputs. (page 30) added note at the end of section 7.7.1.7 to indicate that mini-holdover follows the manual holdover setting. (page 30) in section 7.7.2 , corrected a typo to say the t4 dpll only operates in revertive switching mode rather than ?does not have revertive switching mode.? (page 33, 89, 96) edited section 7.7.6 and the dlimit1 and dlimit3 :fllol descriptions to indicate the t4 dpll?s hard limit is fixed at 80ppm and is not controlled by the hardlim field. (page 39) in section 7.8.1 , added hyperlink to maxim app note hfan-1.0. (pages 44 to 47) in table 7-13 , updated many of the typi cal rms and peak-to-peak jitter numbers to match actual device performance. (page 46) added a 25mhz row to table 7-13 . (page 47). in the 125mhz row of table 7-13 , corrected a typo by changing ?oc4 and oc5 only? to ?oc5 only.? (page 58) rewrote section 7.14 to refer readers to the web or telecom support for the latest initialization scripts. (pages 101 to 104) edited the ofreq1 to ofreq7 fields in the ocr registers to indicate that if the t4 dpll is configured for 62.5mhz, then ofreq = 1100 specifies t4 apll frequency divided by 10 to give an output frequency of 25mhz. (page 130) in table 10-2 , changed i dd18 from 95ma typ to 100ma typ and 115ma max to 120ma max; changed i dd33 from 25ma typ to 37ma typ and 30ma max to 53ma max; changed i ddoc6 and i ddoc7 from 8ma typ to 9ma typ. (page 131) in table 10-3 , changed v dd to v ddio in note 1. (page 131) in table 10-4 , changed v ohlvds to 1.45v typ, 1.65v max; added v ollvds 1.1v typ; changed v oslvds to 1.08v min, 1.28v typ, 1.45v max. (page 131) added note 2 to table 10-4 . (page 132) in table 10-5 , deleted specs i ihpecl and i iilpecl specs and in note 2 changed v dd to v ddio . (page 132) added note 3 to table 10-5 . (page 133) in table 10-6 in the v ihami spec, changed max from v dd + 0.3 to v ddio + 0.3 and deleted the i amiout , v ohami , and v olami specs because the specs in table 7-16 and figure 7-7 are sufficient to govern output signal performance for oc8. (page 133) updated figure 10-3 and table 10-7 and accompanying text to show new recommended external components. (page 134) updated table 10-8 to clarify minimum high time and low time (and therefore duty cycle) for input clocks. (pages 133, 135, 138, 139) added gbd comments (n ote 1) to ac timing characteristics in section 10.

▲Up To Search▲

Price & Availability of DS3101

	To Download DS3101 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .