myson technology mtd392 family coaxial transceiver interface this datasheet contains new product information. myson technology reserves the rights to modify the product specification without notice. no liability is assumed as a result of the use of this product. no rights under any patent accompany the sale of the product. mtd392 revision 2.01 02/25/1997 1/ 10 features compatible with iso/ieee 802.3 10base5 (ethernet) and 10base2 ( cheapernet). functionally compatible with national dp8392c. internal squelch circuitry for noise rejection. reception/transmission mode collision detection. transceiver functions integrated except for signal and power isolation. cd heartbeat externally selectable. advanced low-power, high-performance cmos technology. esd protection greater than 2000 volts. 16-pin plastic dip package, 24-pin ski nny plastic dip package, or 20 and 28-pin plcc packages. built-in led drivers for collision, reception, jabber and transmission status display (mtdx93/x94 only). collision detection mode for reception, transmission and hybrid (mtdx94 only). special test mode allowing continuous transmission for waveform testing (mtdx94 only). general description the mtd392 family includes a series of products, mtd392/3/4 and mtd492/3/4. the mtd392 product family is built for easy mau interface in a coaxial ethernet network. the mtd392 product family integrates the coaxial cable interface functions of medium attachment unit (mau) in ethernet or cheapernet lan applications. in an ethernet 10base5 network, the mtd392 product family is mounted on the thick ethernet coaxial cable and connects to a station through an aui cable. for cheapernet applications, the mtd392 product family is connected to the cheapernet coaxial cable through a bnc connector and is usually mounted on the lan adapter in a station. following is a table describing the differences among the mtd392 product family: product features package types recommended applications mtd392 basic transceiver 16-pdip 28-plcc adapter boards mtd393 mtd392 with built-in leds 20-plcc 24-pdip adapter cards with status leds mtd394 mtd393 with enhanced collision detection mode, special pin for testing 24-pdip 28-plcc mtd393 applications with enhanced collision detection mtd49x mtd39x with improved performance basic mtd39x applications, hub, repeater and mau applications
myson technology mtd392 family mtd392 revision 2.01 02/25/1997 2 / 10 block diagram for mtd392 family high pass equalization low pass filter low pass filter com - + low pass filter 125 10k reference circuit 1k aui driver aui driver carrier sense - + waveform shaping + - dc/ac squelch watch dog timer 26ms jabber reset timer 0.4sec 10mhz osc transmit state machine receive state machine xmtsq clk vee collision hbe fxi gnd coax vee xmt cds recv txo rr+ rr- rx+ rx- cd+ cd- tx+ tx- block diagram for mtdx92 high pass equalization low pass filter low pass filter com - + low pass filter 125 10k reference circuit 1k aui driver aui driver carrier sense - + waveform shaping + - dc/ac squelch watch dog timer 26ms jabber reset timer 0.4sec 10mhz osc transmit state machine receive state machine xmtsq clk vee collision hbe fxi gnd coax vee xmt cds recv txo rr+ rr- rx+ rx- cd+ cd- tx+ tx- jab xmt col rcv block diagram for mtdx93
myson technology mtd392 family mtd392 revision 2.01 02/25/1997 3 / 10 high pass equalization low pass filter low pass filter com - + low pass filter 125 10k reference circuit 1k aui driver aui driver carrier sense - + waveform shaping + - dc/ac squelch watch dog timer 26ms jabber reset timer 0.4sec 10mhz osc transmit state machine receive state machine xmtsq clk 16x collision hbe fxi gnd coax vee xmt cds recv txo rr+ rr- rx+ rx- cd+ cd- tx+ tx- jab xmt col rcv 1x mode clk/1024 test test mod led driver block diagram for mtdx94 1.0 connection diagram (1) mtdx92 pin diagram MTD392N 16 pin pdip mtd392v 28 pin plcc cd+ cd- rx+ vee vee rx- tx+ tx- cds tx0 rxi vee rr- rr+ gnd hbe vee vee vee vee vee(nc) vee(nc) vee(nc) rx+ cd- cd+ cds txd nc rxi vee(nc) vee vee vee vee vee(nc) rr- rx- tx+ tx- hbe gnd gnd rr+ 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9
myson technology mtd392 family mtd392 revision 2.01 02/25/1997 4 / 10 (2) mtdx93 pin diagram mtd393n 24 pin pdip (300 mil) cd+ cd- rx+ gnd vee rx- col jab tx+ tx- xmt rcv cds tx0 rxi vee vee rr- rr+ gnd gnd nc nc hbe 1 2 3 4 5 6 7 8 9 10 11 12 24 23 22 21 20 19 18 17 16 15 14 13 mtd393v 20 pin plcc gnd vee rx- col jab rx+ cd- cd+ cds txo rxi vee rr- rr+ gnd tx+ tx- xmt rcv hbe (3) mtdx94 pin diagram mtd394n 24 pin pdip (300 mil) cd+ cd- rx+ gnd vee rx- col jab tx+ tx- xmt rcv cds tx0 rxi vee vee rr- rr+ gnd gnd mod~ tst~ hbe 1 2 3 4 5 6 7 8 9 10 11 12 24 23 22 21 20 19 18 17 16 15 14 13 mtd394v 28 pin plcc rx+ gnd vee rx- col jab tx+ gnd gnd cd- cd+ gnd cds txd rxi vee vee vee rr- rr+ gnd tx- xmt rcv hbe tst mod gnd 2.0 pin descriptions name i/o mtd x92 pin# mtd x93 pin# mtd x94 pin# description tx+,tx- i 7 8 9 10 9 10 transmission data input. a balanced differential line receiver that receives input from the off-chip manchester code converter (mcc) to the transmitter. the common mode voltage on tx is set internally. hbe i 9 13 13 heartbeat enabler. the cd heartbeat test is enabled when hbe is connected to ground and disabled when hbe is connected to vee. rr+,rr- i 11 12 18 19 18 19 external resistor. a 1k w ,/1% resistor should be connected across these pins to correctly set internal operating currents. rr+ is internally shorted to gnd.
myson technology mtd392 family mtd392 revision 2.01 02/25/1997 5 / 10 rxi i 14 22 22 network receiving input. should be connected to the coax center conductor. signals meeting receiver squelch limits are recovered and output on rx /rxi also detects the collision voltage level. cds i 16 24 24 collision detecting sense. connects directly to the coax shield, providing a reference for the collision detection voltage level for receiving-mode detection. an external bias network can be used to shift the detection threshold for transmission- detection mode. for hybrid mode collision detection, a 400 w resistor should be connected from cds to gnd. rx+,rx- o 3 6 3 6 3 6 receiving data output. a balanced differential output drives data recovered from the network to the mcc. these outputs are also open sources, and pull-down resistors from 510 w to vee are required. to minimize power dissipation, both open source outputs are disabled during idle conditions, allowing the common mode on the pull-down resistor to be pulled to vee. cd+,cd- o 1 2 1 2 1 2 collision output. a balanced differential line driver drives this output pair from the collision detection circuitry. a 10mhz signal from the internal oscillator is transferred to these outputs in the event of collision or excessive transmission (jabber), or during heartbeat condition. these output s are open sources, and pull-down resistors from 510 w to vee are required. to minimize power dissipation, both open source outputs are disabled during idle condition, allowing the common mode on the pull-down resistors to be pulled to vee. txo o 15 23 23 transmitter output. should be connected to the coaxial cable via one serial isolation diode for cheapernet/ thinnet (10 base2) or 2 serial isolation diodes for thicknet (10 base5). gnd 10 4 16 17 4 16 17 positive supply pin (ground). should be connected to the coax shield. vee 4 5 13 5 20 21 5 20 21 negative power supply. -9 volts. a 0.1 m f decoupling capacitor must be connected across gnd and vee as close to the device as possible. col, jab, xmt, rcv, o 7 8 11 12 transceiver status indicators. led displays for collision, jabber, transmission and reception. these pins are open- drain output buffers that are used to drive led status indicators. they are designed to supply 8 ma sinking capability. tst- i 14 test enabler. when both tst- and mod- pins are shorted to vee, mtdx94 enters into test mode. in this mode, the jabber function is disabled and all state timing is accelerated by 1024 times. this pin has a 50k w internal pull-up resistor. mod- i 15 mode selection. along with the tst- pin, determines the collision detection method of mtdx94. if both mod- and tst- are connected to gnd, mtdx94 implements receiving- mode collision detection. the typical detection threshold in receiving-mode is -1.53v. to implement transmission-mode collision detection, the detection threshold can be lowered by placing a resistor bias network on the cds pin. when the tst- pin is connected to gnd and the mod- pin is connected to vee, mtdx94 uses hybrid-mode for collision detection. in this mode, the threshold is set at -0.42v during idle or
myson technology mtd392 family mtd392 revision 2.01 02/25/1997 6 / 10 receiving operation. during transmission, the detection threshold is increased to -0.42v plus its own transmission level on the cds pin. when tst- is connected to vee and mod- is connected to gnd, mtdx94 uses the transmit- hybrid mode for collision detection. this mode is identical to hybrid-mode, except that during idle or receiving operation, the detection threshold is set at -1.53v. for proper operation of hybrid and transmission-hybrid mode, a 400 w resistor should be connected between the cds pin and gnd. this pin has a 50 k w internal pull-up resistor. 3.0 absolute maximum ratings dc supply voltage (vee) -12v input voltage gnd+0.3 to vee-0.3v storage temperature -65 o to 150 o c ambient operating temperature 0 o to 70 o c esd protection except rxi 2000v 4.0 operating conditions dc supply voltage (vee) 8.55-9.45v operating temperature 0 o to 70 o c 5.0 electrical characteristics (under operating conditions) (note 1) parameter symbol min typ max unit recommended supply voltage vee -8.55 -9.0 -9.45 v non-transmitting supply current (vee to gnd) iee - -25 -35 ma transmission - -70 -80 ma receiving input bias current (rxi) irxi -2 - +25 m a transmitting output dc current (txo) itdc 37 41 45 ma transmitting output ac current (txo) itac 28 - itdc ma collision threshold (receiving mode) vcd -1.45 -1.53 -1.62 v collision threshold (hybrid mode) (mtdx94 only) vhcd -0.38 -0.45 -0.52 v carrier sense threshold (rxi) vcs -0.38 -0.45 -0.52 v differential output voltage (rx ,cd ) vod 500 - 1500 mv dc common mode output voltage (rx ,cd ) (note2) voc -1.0 -2.0 -3.0 v idle state differential offset voltage(rx ,cd ) vob - 0 40 mv transmission squelch threshold(tx ) (note 3) vts -175 -225 -300 mv input capacitance (rxi) cx - 1.5 - pf shunt resistance-non-transmitting rrxi 100 - - k w shunt resistance-transmitting rtxo 10 - - k w notes :1. testing is done under the testing load defined in figure 6. 2. during idle condition, voc is pulled down to vee to minimize the power dissipation across the l oad resistors connected to rx and cd pins. 3. for a minimum pulse width of 3 40 ns .
myson technology mtd392 family mtd392 revision 2.01 02/25/1997 7 / 10 6.0 switching characteristics (under operating conditions) (note 1) parameter symbol min typ max unit receiving start-up delay (rxi to rx ) tron - 2.5 5 bits receiving propagation delay (rxi to rx ) trd - 25 50 ns differential output rise time (rx ,cd ) trr - 4 7 ns differential output fall time (rx ,cd ) trf - 4 7 ns reception and cable total jitter trj - 2 - ns transmission start-up delay ttst - 1 2 bits transmission propagation delay ttd - 25 50 ns transmission rise time (10%-90%) (txo) ttr 20 25 30 ns transmission fall time (10%-90%) (txo) ttf 20 25 30 ns ttr and trf mismatch ttm - 0.5 3.0 ns transmission skew(txo) tts - 0.5 2 ns transmission turn-on pulse width at vts(tx+) (note 4) tton 10 20 40 ns transmission turn-off delay ttoff 130 200 300 ns collision turn-on delay tcon - 7 13 bits collision turn-off delay tcoff - - 20 bits collision frequency (cd ) fcp 8.5 10 12.5 mhz collision pulse width (cd ) tcp 40 50 60 ns cd heartbeat delay (tx to cd ) thon 0.6 1.1 1.6 m s cd heartbeat duration(cd ) thw 0.5 1.0 1.5 m s jabber activation delay(tx to cd ) tja 20 26 32 ms jabber reset timeout (tx to txo and cd ) tjr 300 420 550 ms notes: 4. for a minimum pulse amplitude of 3 -300 mv. 7.0 timing diagram for mtd392 family input to rxi rx+ rx- t ron 50% 50% t rd 90% 10% t rf t rr t roff figure 1. reception timing tx+ tx- txo output t tst t toff t tidl v ts t ton t td t tf t tr 50% 50% 90% 10% figure 2. transmission timing t hon t hw tx+ tx- cd+ cd- figure 3. heartbeat timing
myson technology mtd392 family mtd392 revision 2.01 02/25/1997 8 / 10 v cd (min) t con v cd (max) -1.75v 0v -6.8v -1.2v t coff 1/f cp t cp input to rxi cd+ cd- figure 4. collision timing tx+ tx- txo cd+ cd- t ja t jr figure 5. jabber timing 25 w txo transmitter output 39 w 510 w 50 m h* 39 w 510 w vee receiver (rx ) collision(cd ) outputs + - figure 6. test loads
myson technology mtd392 family mtd392 revision 2.01 02/25/1997 9 / 10 8.0 package dimension for 392 family a. 24-pin pdip unit: mil 930+/-10 r40 55+/-20 312+/-12 r10max (4x) 80+/-20 250+/-4 350+/-20 10 18+/-2typ 60+/-5typ 15min. 15max 115min 100typ 35+/-5 7typ 1245+/-10 65+/-4 65+/-4 b. 16-pin pdip unit: mil 75+/-20 90+/-20 r40 55+/-20 312+/-12 100+/-20 245+/-20 355+/-50 10 18+/-5typ 60+/-15 15min. 15max 130 +/-15 15max 100+/-20 35+/-5 7ty p 760+/-20 60+/-4 60+/-4 310max
myson technology mtd392 family mtd392 revision 2.01 02/25/1997 10 / 10 c. 28-pin plcc unit: inch pin #1 hole 0.453 +/-0.003 0.490 +/-0.005 0.4902 +/-0.005 0.453 +/-0.003 0.045*45 0 0.180 max. 0.020 min. 0.410 +/-0.02 0.300 0.070 0.070 7 0 typ. 0.010 0.050 typ. 0.013~0.021 typ. 0.026~0.032 typ. d. 20-pin plcc unit: inch pin #1 hole 0.353 +/-0.003 0.390 +/-0.005 0.390 +/-0.005 0.353 +/-0.003 0.045*45 0 0.180 max. 0.020 min. 0.310 +/-0.02 0.200 0.070 0.070 7 0 typ. 0.010 0.050 typ. 0.013~0.021 typ.
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