View MAX3221E_4144955.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

general description the MAX3221E/max3223e/max3243e are 3v-powered eia/tia-232 and v.28/v.24 communications interfaces with automatic shutdown/wakeup features, high data- rate capabilities, and enhanced electrostatic discharge (esd) protection. all transmitter outputs and receiver inputs are protected to ?5kv using iec 1000-4-2 air- gap discharge, to ?kv using iec 1000-4-2 contact discharge, and to ?5kv using the human body model. the MAX3221E/max3223e/max3243e achieve a 1? supply current with maxim? revolutionary autoshutdown feature. they save power without changes to the existing bios or operating system by enter- ing low-power shutdown mode when the rs-232 cable is disconnected, or when the transmitters of the connected peripherals are off. the transceivers have a proprietary low-dropout trans- mitter output stage, delivering true rs-232 performance from a +3.0v to +5.5v supply with a dual charge pump. the charge pump requires only four small 0.1? capaci- tors for operation from a +3.3v supply. each device is guaranteed to run at data rates of 250kbps while main- taining rs-232 output levels. the MAX3221E contains just one driver and one receiver, making it the smallest single-supply rs-232 transceiver. the max3223e has two drivers and two receivers. the max3243e is a complete 3-driver/5-receiver serial port ideal for notebook or subnotebook computers. it also includes two noninverting receiver outputs that are always active, allowing external devices to be monitored without forward biasing the protection diodes in circuitry that may be powered down. the MAX3221E, max3223e, and max3243e are avail- able in space-saving ssop and tssop packages. applications notebook, subnotebook, and palmtop computers cellular phones battery-powered equipment hand-held equipment peripherals printers features esd protection for rs-232 i/o pins 15kv?uman body model 8kv?ec 1000-4-2, contact discharge 15kv?ec 1000-4-2, air-gap discharge latchup free 1a supply current when port is disconnected or inactive 250kbps guaranteed data rate 6v/s guaranteed slew rate meets eia/tia-232 specifications down to 3.0v smallest single-supply rs-232 transceiver (MAX3221E) guaranteed mouse driveability (max3243e) small 0.1f capacitors MAX3221E/max3223e/max3243e ? 15kv esd-protected, 1a, 3.0v to 5.5v, 250kbps, rs-232 transceivers with autoshutdown ________________________________________________________________ maxim integrated products 1 19-1283; rev 4; 1/02 part MAX3221E cae MAX3221Eeae -40 c to +85 c 0 c to +70 c temp. range pin-package 16 ssop 16 ssop autoshutdown is a trademark of maxim integrated products, inc. ? covered by u.s. patent numbers 4,636,930; 4,679,134; 4,777,577; 4,797,899; 4,809,152; 4,897,774; 4,999,761; 5,649,210; and othe r patents pending. pin configurations appear at end of data sheet. typical operating circuits appear at end of data sheet. max3223eepp -40 c to +85 c 20 plastic dip max3223eeap -40 c to +85 c 20 ssop max3243e cwi 0 c to +70 c 28 wide so max3243ecai 0 c to +70 c 28 ssop max3243eewi -40 c to +85 c 28 wide so max3243eeai -40 c to +85 c 28 ssop max3223e cpp max3223ecap 0 c to +70 c 0 c to +70 c 20 plastic dip 20 ssop ordering information selector guide MAX3221E max3223e max3243e 1/1 2/2 +3.0 to +5.5 +3.0 to +5.5 +3.0 to +5.5 3/5 ? ? ? part no. of drivers/ receivers v cc range (v) autoshutdown max3223ecup 0 c to +70 c 20 tssop max3223eeup -40 c to +85 c 20 tssop for pricing, delivery, and ordering information, please contact maxim/dallas direct! at 1-888-629-4642, or visit maxim? website at www.maxim-ic.com. max3243ecui 0 c to +70 c 28 tssop max3243eeui -40 c to +85 c 28 tssop
MAX3221E/max3223e/max3243e 15kv esd-protected, 1a, 3.0v to 5.5v, 250kbps, rs-232 transceivers with autoshutdown 2 _______________________________________________________________________________________ absolute maximum ratings electrical characteristics (v cc = +3.0v to +5.5v, c1?4 = 0.1? (note 2), t a = t min to t max , unless otherwise noted. typical values are at t a = +25 c.) stresses beyond those listed under ?bsolute maximum ratings?may cause permanent damage to the device. these are stress rating s only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specificatio ns is not implied. exposure to absolute maximum rating conditions for extended periods may affect device reliability. v cc to gnd ..............................................................-0.3v to +6v v+ to gnd (note 1) ..................................................-0.3v to +7v v- to gnd (note 1) ...................................................+0.3v to -7v v+ + | v- | (note 1) .................................................................+13v input voltages t_in, en , forceon, forceoff to gnd ............-0.3v to +6v r_in to gnd ......................................................................?5v output voltages t_out to gnd................................................................?3.2v r_out, r2outb, invalid to gnd .........-0.3v to (v cc + 0.3v) short-circuit duration t_out to gnd .........................................................continuous continuous power dissipation (t a = +70 c) 16-pin ssop (derate 7.14mw/ c above +70 c) ...........571mw 20-pin plastic dip (derate 11.11mw/ c above +70 c)....889mw 20-pin ssop (derate 8.00mw/ c above +70 c) ...........640mw 20-pin tssop (derate 10.9mw/ c above +70 c) .........879mw 28-pin ssop (derate 9.52mw/ c above +70 c)............762mw 28-pin tssop (derate 12.8mw/ c above +70 c) .......1026mw operating temperature ranges max32_ _ec_ _ ....................................................0 c to +70 c max32_ _ee_ _..................................................-40 c to +85 c storage temperature range .............................-65 c to +160 c lead temperature (soldering, 10s) .................................+300 c note 1: v+ and v- can have maximum magnitudes of 7v, but their absolute difference cannot exceed 13v. v cc = 5.0v receiver outputs autoshutdown (forceon = gnd, forceoff = v cc ) logic inputs dc characteristics (v cc = 3.3v or 5.0v, t a = +25?) r_out receivers disabled output leakage current ?.05 ?0 ? negative threshold positive threshold figure 5a v cc = 3.3v t_in, en , forceon, forceoff conditions i out = -1.0ma i out = 1.6ma figure 5a i out = -1.0ma i out = 1.6ma t_in, en , forceon, forceoff forceon = forceoff = v cc , no load forceoff = gnd, all r_in = gnd forceon = gnd, forceoff = v cc, all r_in open v cc - 0.6 v invalid output voltage high -0.3 0.3 v receiver input threshold to invalid output low 0.4 v invalid output voltage low -2.7 v receiver input threshold to invalid output high 2.7 0.3 1 ma supply current, autoshutdown disabled 1.0 10 ? supply current, shutdown supply current, autoshutdown 2.0 parameter min typ max units input logic threshold low 0.8 v 1.0 10 ? input logic threshold high 2.4 v output voltage low 0.4 v output voltage high v cc - 0.6 v cc - 0.1 v symbol transmitter input hysteresis 0.5 v t_in, en , forceon, forceoff input leakage current ?.01 ? ?
kv MAX3221E/max3223e/max3243e 15kv esd-protected, 1a, 3.0v to 5.5v, 250kbps, rs-232 transceivers with autoshutdown _______________________________________________________________________________________ 3 electrical characteristics (continued) (v cc = +3.0v to +5.5v, c1?4 = 0.1? (note 2), t a = t min to t max , unless otherwise noted. typical values are at t a = +25 c.) parameter min typ max units ?5 output short-circuit current ?0 ma output resistance 300 10m ? output leakage current ? input threshold low 0.6 1.2 v ? ?.4 output voltage swing v conditions v cc = v+ = v- = 0, t out = ?v v out = ?2v, v cc = 0 or 3v to 5.5v, transmitters disabled all transmitter outputs loaded with 3k ? to ground receiver positive or negative threshold to invalid high 1 ? v cc = 5v, figure 5b input hysteresis 0.5 v input threshold high v input resistance 35 7 k ? 0.8 1.5 1.8 2.4 1.5 2.4 t a = +25? t a = +25? ?.0 transmitter output voltage v t1in = t2in = gnd, t3in = v cc , t3out loaded with 3k ? to gnd, t1out and t2out loaded with 2.5ma each t invh symbol v cc = 3.3v v cc = 5.0v v cc = 3.3v v cc = 5.0v ?5 iec 1000-4-2 air-gap discharge receiver positive or negative threshold to invalid low 30 ? v cc = 5v, figure 5b t invl input voltage range -25 25 v receiver or transmitter edge to transmitters enabled 100 ? v cc = 5v, figure 5b t wu input voltage range -25 25 v ? iec 1000-4-2 contact discharge r_in, t_out ?5 human body model kv receiver inputs transmitter outputs mouse driveability (max3243e) esd protection
typical operating characteristics (v cc = +3.3v, 250kbps data rate, 0.1? capacitors, all transmitters loaded with 3k ? and c l , t a = +25?, unless otherwise noted.) -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 0 1000 2000 3000 4000 5000 MAX3221E/max3223e transmitter output voltage vs. load capacitance MAX3221E-01 load capacitance (pf) transmitter output voltage (v) v out+ t1 transmitting at 250kbps t2 (max3223e) transmitting at 15.6kbps v out- 0 2 4 6 8 10 12 14 16 0 1000 2000 3000 4000 5000 MAX3221E/max3223e slew rate vs. load capacitance max3221-toc2 load capacitance (pf) slew rate (v/ s) -slew +slew for data rates up to 250kbps MAX3221E/max3223e/max3243e 15kv esd-protected, 1a, 3.0v to 5.5v, 250kbps, rs-232 transceivers with autoshutdown 4 _______________________________________________________________________________________ timing characteristics?ax3221e/max3223e/max3243e (v cc = +3.0v to +5.5v, c1?4 = 0.1? (note 2), t a = t min to t max , unless otherwise noted. typical values are at t a = +25 c.) note 2: c1?4 = 0.1?, tested at 3.3v ?0%. c1 = 0.047?, c2?4 = 0.33?, tested at 5.0v ?0%. note 3: transmitter skew is measured at the transmitter zero cross points. t plh r l = 3k ? , c l = 1000pf, one transmitter switching t phl symbol ? t phl - t plh ? ? t phl - t plh ? receiver output disable time ns conditions ? 0.15 receiver propagation delay c l = 150pf to 1000pf kbps units min typ max parameter (note 3) ns 50 receiver skew ns 100 transmitter skew v cc = 3.3v, r l = 3k ? to 7k ? , t a = +25 c, measured from +3v to -3v or -3v to +3v, one transmitter switching v/? transition-region slew rate 630 c l = 150pf 250 0.15 maximum data rate ns normal operation receiver output enable time 200 normal operation 200
MAX3221E/max3223e/max3243e 15kv esd-protected, 1a, 3.0v to 5.5v, 250kbps, rs-232 transceivers with autoshutdown _______________________________________________________________________________________ 5 typical operating characteristics (continued) (v cc = +3.3v, 250kbps data rate, 0.1? capacitors, all transmitters loaded with 3k ? and c l , t a = +25 c, unless otherwise noted.) -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 0 max3243e transmitter output voltage vs. load capacitance max3224e-04 load capacitance (pf) transmitter output voltage (v) 2000 3000 1000 4000 5000 1 transmitter at 250kbps 2 transmitters at 15.6kbps v out+ v out- 0 4 2 8 6 12 10 14 0 1000 2000 3000 4000 5000 max3243e slew rate vs. load capacitance max3243e-05 load capacitance (pf) slew rate (v/ s) 0 30 20 10 40 50 60 0 2000 1000 3000 4000 5000 max3243e operating supply current vs. load capacitance max3243e-06 load capacitance (pf) supply current (ma) 250kbps 120kbps 20kbps t1 transmitting at 250kbps t2 (max3223e) transmitting at 15.6kbps 0 5 10 15 20 25 30 35 40 45 0 2000 1000 3000 4000 5000 MAX3221E/max3223e operating supply current vs. load capacitance max3224e-03 load capacitance (pf) supply current (ma) 250kbps 120kbps 20kbps t1 transmitting at 250kbps t2 (max3223e) transmitting at 15.6kbps
MAX3221E/max3223e/max3243e 15kv esd-protected, 1a, 3.0v to 5.5v, 250kbps, rs-232 transceivers with autoshutdown 6 _______________________________________________________________________________________ pin description -5.5v generated by the charge pump v- rs-232 receiver inputs r_in ttl/cmos receiver outputs r_out output of the valid signal detector. invalid is enabled high if a valid rs-232 level is present on any receiver input. invalid +5.5v generated by the charge pump v+ negative terminal of the voltage doubler charge-pump capacitor c1- positive terminal of inverting charge-pump capacitor c2+ negative terminal of inverting charge-pump capacitor c2- positive terminal of the voltage doubler charge-pump capacitor c1+ receiver enable control. drive low for normal operation. drive high to force the receiver outputs (r_out) into a high-impedance state. en function ttl/cmos transmitter inputs t_in drive high to override automatic circuitry keeping transmitters and charge pump on ( forceoff must be high) (table 1). forceon _______________detailed description dual charge-pump voltage converter the MAX3221E/max3223e/max3243e? internal power supply consists of a regulated dual charge pump that provides output voltages of +5.5v (doubling charge pump) and -5.5v (inverting charge pump), over the +3.0v to +5.5v v cc range. the charge pumps operate in discontinuous mode: if the output voltages are less than 5.5v, the charge pumps are enabled; if the output voltages exceed 5.5v, the charge pumps are disabled. each charge pump requires a flying capacitor (c1, c2) and a reservoir capacitor (c3, c4) to generate the v+ and v- supplies. rs-232 transmitters the transmitters are inverting level translators that con- vert cmos-logic levels to 5.0v eia/tia-232 levels. they guarantee a 250kbps data rate with worst-case loads of 3k ? in parallel with 1000pf, providing compatibility with pc-to-pc communication software such as laplink. transmitters can be paralleled to drive mul- tiple receivers. the max3243e has been specifically designed to drive serial mice. figure 1 shows a com- plete system connection. when forceoff is driven to ground, or the autoshutdown circuitry senses invalid voltage levels on all receiver inputs, the transmitters are disabled and the outputs are forced into a high-impedance state. when powered off or shut down, the output can be driven up to ?2v. the transmitter inputs do not have pull-up resistors. 7 8 9 10 3 4 5 6 2 1 11 12 name MAX3221E rs-232 transmitter outputs t_out 13 ttl/cmos noninverting complementary receiver output. always active. r2outb 7 9, 16 10, 15 11 3 4 5 6 2 1 12, 13 14 3 4? 15?9 21 27 24 1 2 28 12, 13, 14 23 max3223e 8, 17 max3243e 9, 10, 11 20 pin 14 18 25 gnd ground 15 19 26 v cc +3.0v to +5.5v supply voltage 16 20 22 forceoff force-off input, active low. drive low to shut down transmitters, receivers (max3243e, except r2outb), and on-board charge pump. this overrides all automatic circuitry and forceon (table 1). laplink is a trademark of traveling software.
MAX3221E/max3223e/max3243e 15kv esd-protected, 1a, 3.0v to 5.5v, 250kbps, rs-232 transceivers with autoshutdown _______________________________________________________________________________________ 7 rs-232 receivers the MAX3221E/max3223e/max3243e? receivers con- vert rs-232 signals to cmos-logic output levels. all receivers have inverting three-state outputs and can be active or inactive. in shutdown ( forceoff = low) or in autoshutdown, the MAX3221E/max3223e? receivers are active (table 1). drive en high to place the receiv- er(s) in a high-impedance state. the max3243e? receivers are high-impedance when the part is in shut- down ( forceoff = low). the max3243e features an extra, always-active com- plementary output (r2outb). r2outb monitors receiver activity while the other receivers are high- impedance. this allows ring indicator to be monitored without forward biasing other devices connected to the receiver outputs. this is ideal for systems where v cc drops to 0 in shutdown to accommodate peripherals such as uarts (figure 2). max3243e i/o chip with uart cpu rs-232 power- management unit or keyboard controller forceoff forceon invalid max3243e t1out r2outb tx 5k ? uart v cc t1in three-stated logic transition detector r2in protection diode r2out forceoff = gnd v cc to p rx previous rs-232 tx uart shdn = gnd v cc v cc gnd rx 5k ? a) older rs-232: powered-down uart draws current from active receiver output in shutdown. b) new max3243e: in shutdown, r2outb is used to monitor external devices and r2out is three stated, eliminating a current path through the uart's protection diode. gnd protection diode i i figure 1. interface under control of pmu figure 2. the max3243e detects rs-232 activity when the uart and interface are shut down.
MAX3221E/max3223e/max3243e 15kv esd-protected, 1a, 3.0v to 5.5v, 250kbps, rs-232 transceivers with autoshutdown 8 _______________________________________________________________________________________ table 1. output control truth table +0.3v -0.3v invalid to max32_ _e power supply and transmitters r_in * transmitters are disabled, reducing supply current to 1 a if all receiver inputs are between +0.3v and -0.3v for at least 30 s. 30 s counter r figure 3a. max32_ _e entering 1? supply mode via autoshutdown +2.7v -2.7v invalid to max32_ _e power supply r_in *transmitters are enabled if: any receiver input is greater than +2.7v or less than -2.7v. any receiver input has been between +0.3v and -0.3v for less than 30 s. 30 s counter r figure 3b. max32_ _e with transmitters enabled using autoshutdown x = don? care the MAX3221E/max3223e/max3243e feature an invalid output that is enabled low when no valid rs-232 signal levels have been detected on all receiver inputs. invalid is functional in any mode (figures 3 and 5). autoshutdown the MAX3221E/max3223e/max3243e achieve a 1? supply current with maxim? new autoshutdown fea- ture, which operates when forceon is low and forceoff is high. when these devices sense no valid signal levels on all receiver inputs for 30?, the on- board charge pump and drivers are shut off, reducing supply current to 1?. this occurs if the rs-232 cable is disconnected or the connected peripheral transmit- ters are turned off. the device turns on again when a valid level is applied to any rs-232 receiver input. as a result, the system saves power without changes to the existing bios or operating system. table 2 and figure 3c summarize the MAX3221E/ max3223e/max3243e operating modes. forceon and forceoff override autoshutdown. when neither control is asserted, the ic selects between these states automatically, based on receiver input levels. figures 3a, 3b, and 5a depict valid and invalid rs-232 receiver levels. figure 5 shows the input levels and timing dia- gram for autoshutdown operation. a mouse or other system with autoshutdown may need time to wake up. figure 4 shows a circuit that forces the transmitters on for 100ms, allowing enough time for the other system to realize that the MAX3221E/ max3223e/ max3243e are awake. if the other system transmits valid rs-232 signals within that time, the rs- 232 ports on both systems remain enabled. 0 0 0 1 x 1 forceon x active active active r2outb (max3243e) active active active active active active high-z r_out (MAX3221E/ max3223e) active active high-z high-z 1 1 1 1 0 1 forceoff 0 active high-z active t_out high-z active active high-z active active active r_out (max3243e) high-z active active high-z 0 0 yes no normal operation (autoshutdown) yes 0 x normal operation (forced on) x shutdown (forced off) x en (MAX3221E/ max3223e) valid receiver level 0 x operation status 1 1 1 0 active high-z 1 high-z active shutdown (autoshutdown) no 1
MAX3221E/max3223e/max3243e _______________________________________________________________________________________ 9 when shut down, the device? charge pumps are off, v+ is pulled to v cc , v- is pulled to ground, and the trans- mitter outputs are high impedance. the time required to exit shutdown is typically 100? (figure 5b). software-controlled shutdown if direct software control is desired, invalid can be used to indicate dtr or ring indicator signal. connect forceoff and forceon together to disable auto- shutdown so the line acts like a shdn input. 15kv esd protection as with all maxim devices, esd-protection structures are incorporated on all pins to protect against electrostatic discharges encountered during handling and assembly. the driver outputs and receiver inputs of the MAX3221E/max3223e/max3243e have extra protection against static electricity. maxim? engineers have devel- oped state-of-the-art structures to protect these pins against esd of ?5kv without damage. the esd struc- tures withstand high esd in all states: normal operation, shutdown, and powered down. after an esd event, maxim? e versions keep working without latchup, where- as competing rs-232 products can latch and must be powered down to remove latchup. see table 4. v- v cc 0 v+ 0 v cc t invl t wu invalid region receiver input voltage (v) invalid output (v) t invh transmitters enabled, invalid high receiver input levels autoshutdown, transmitters disabled, 1 a supply current, invalid low transmitters enabled, invalid high -2.7v -0.3v +2.7v +0.3v 0 indeterminate indeterminate b) a) figure 5. autoshutdown trip levels forceon master shdn line 0.1 f1m ? forceoff MAX3221E max3223e max3243e power- management unit figure 4. autoshutdown with initial turn-on to wake up a mouse or another system forceoff power down invalid forceon invalid is an internally generated signal that is used by the autoshutdown logic and appears as an output of the device. power down is only an internal signal. it controls the operational status of the transmitters and the power supplies. figure 3c. max32_ _e autoshutdown logic table 2. invalid truth table low no high yes invalid output rs-232 signal present at any receiver input 15kv esd-protected, 1a, 3.0v to 5.5v, 250kbps, rs-232 transceivers with autoshutdown
MAX3221E/max3223e/max3243e 15kv esd-protected, 1a, 3.0v to 5.5v, 250kbps, rs-232 transceivers with autoshutdown 10 ______________________________________________________________________________________ esd protection can be tested in various ways; the trans- mitter outputs and receiver inputs of this product family are characterized for protection to the following limits: 1) ?5kv using the human body model 2) ?kv using the contact discharge method specified in iec1000-4-2 3) ?5kv using iec1000-4-2? air-gap method esd test conditions esd performance depends on a variety of conditions. contact maxim for a reliability report that documents test setup, test methodology, and test results. human body model figure 6a shows the human body model, and figure 6b shows the current waveform it generates when dis- charged into a low impedance. this model consists of a 100pf capacitor charged to the esd voltage of inter- est, which is then discharged into the test device through a 1.5k ? resistor. iec1000-4-2 the iec1000-4-2 standard covers esd testing and per- formance of finished equipment; it does not specifically refer to integrated circuits. the MAX3221E/ max3223e/max3243e help you design equipment that meets level 4 (the highest level) of iec1000-4-2, with- out the need for additional esd-protection components. the major difference between tests done using the human body model and iec1000-4-2 is higher peak current in iec1000-4-2, because series resistance is lower in the iec1000-4-2 model. hence, the esd with- stand voltage measured to iec1000-4-2 is generally lower than that measured using the human body model. figure 7a shows the ieee1000-4-2 model and figure 7b shows the current waveform for the ?kv iec1000-4-2 level 4 esd contact-discharge test. the air-gap test involves approaching the device with a charged probe. the contact-discharge method connects the probe to the device before the probe is energized. charge-current limit resistor discharge resistance storage capacitor c s 100pf r c 1m ? r d 1500 ? high- voltage dc source device under test charge current limit resistor discharge resistance storage capacitor c s 150pf r c 50m ? to 100m ? r d 330 ? high- voltage dc source device under test figure 7a. iec1000-4-2 esd test model t r = 0.7ns to 1ns 30ns 60ns t 100% 90% 10% i peak i figure 7b. iec1000-4-2 esd generator current waveform figure 6a. human body esd test models i p 100% 90% 36.8% t rl time t dl current waveform peak-to-peak ringing (not drawn to scale) i r 10% 0 0 amperes figure 6b. human body model current waveform
machine model the machine model for esd tests all pins using a 200pf storage capacitor and zero discharge resistance. its objective is to emulate the stress caused by contact that occurs with handling and assembly during manufactur- ing. of course, all pins require this protection during manufacturing, not just rs-232 inputs and outputs. therefore, after pc board assembly, the machine model is less relevant to i/o ports. ___________applications information capacitor selection the capacitor type used for c1?4 is not critical for proper operation; either polarized or nonpolarized capacitors may be used. the charge pump requires 0.1? capacitors for 3.3v operation. for other supply voltages, refer to table 3 for required capacitor values. do not use values smaller than those listed in table 3. increasing the capacitor values (e.g., by a factor of 2) reduces ripple on the transmitter outputs and slightly reduces power consumption. c2, c3, and c4 can be increased without changing c1? value. however, do not increase c1 without also increasing the values of c2, c3, and c4 to maintain the proper ratios (c1 to the other capacitors). when using the minimum required capacitor values, make sure the capacitor value does not degrade exces- sively with temperature. if in doubt, use capacitors with a larger nominal value. the capacitor? equivalent series resistance (esr) usually rises at low temperatures and influences the amount of ripple on v+ and v-. power-supply decoupling in most circumstances, a 0.1? v cc bypass capacitor is adequate. in applications that are sensitive to power- supply noise, use a capacitor of the same value as the charge-pump capacitor c1. connect bypass capacitors as close to the ic as possible. transmitter outputs when exiting shutdown figure 8 shows two transmitter outputs when exiting shut down mode. as they become active, the two trans- mitter outputs are shown going to opposite rs-232 lev- els (one transmitter output is high, the other is low). each transmitter is loaded with 3k ? in parallel with 1000pf. the transmitter outputs display no ringing or undesirable transients as they come out of shutdown, and are enabled only when the magnitude of v- exceeds approximately -3v. high data rates the MAX3221E/max3223e/max3243e maintain the rs- 232 ?.0v minimum transmitter output voltage even at high data rates. figure 9 shows a transmitter loopback test circuit. figure 10 shows a loopback test result at 120kbps, and figure 11 shows the same test at 250kbps. for figure 10, all three transmitters were driven simulta- neously at 120kbps into rs-232 loads in parallel with 1000pf. for figure 11, a single transmitter was driven at 250kbps, and all three transmitters were loaded with an rs-232 receiver in parallel with 1000pf. mouse driveability (max3243e) the max3243e has been specifically designed to power serial mice while operating from low-voltage power sup- plies. it has been tested with leading mouse brands such as logitech and microsoft. when tested, the max3243e successfully drove all serial mice and met their respective current and voltage requirements. the max3243e? regu- lated dual charge pump ensures the transmitters will sup- ply at least ?v during worst-case conditions. figure 12a shows the transmitter outputs under increasing load cur- rent. the autoshutdown feature does not work with a mouse, so forceoff and forceon should be con- nected to v cc . figure 12b (on the following page) shows a mouse driver test circuit. to achieve mouse driveability with 1? supply current when the port is inactive, use parts with the autoshutdown plus feature (such as the max3244e and max3245e). MAX3221E/max3223e/max3243e 15kv esd-protected, 1a, 3.0v to 5.5v, 250kbps, rs-232 transceivers with autoshutdown ______________________________________________________________________________________ 11 0.33 0.047 4.5 to 5.5 0.1 0.1 3.15 to 3.6 0.22 0.22 3.0 to 3.6 c2, c3, c4 (?) c1, c bypass (?) v cc (v) table 3. required capacitor values 1 0.22 3.0 to 5.5 40 s/div t2out forceon = forceoff t1out 5v/div 2v/div v cc = 3.3v c1?4 = 0.1 f figure 8. transmitter outputs exiting shutdown or powering up
figure 9. loopback test circuit MAX3221E max3223e max3243e 5k ? r_ in r_ out en (MAX3221E/3e) c2- c2+ c1- c1+ v- v+ v cc c4 c3 c1 c2 0.1 f v cc forceoff t_ out t_ in gnd v cc 0 1000pf 2 s/div t1in t1out r1out 5v/div 5v/div 5v/div v cc = 3.3v figure 10. loopback test result at 120kbps MAX3221E/max3223e/max3243e 15kv esd-protected, 1a, 3.0v to 5.5v, 250kbps, rs-232 transceivers with autoshutdown 12 ______________________________________________________________________________________ table 4. 15kv esd-protected, 3.0v to 5.5v powered rs-232 transceivers from maxim part supply voltage range (v) no. of tx/rx guaranteed data rate (kbps) supply current (a) max3241e +3.0 to +5.5 3/5 250 300 max3243e +3.0 to +5.5 3/5 250 1 max3244e +3.0 to +5.5 3/5 250 1 max3245e +3.0 to +5.5 3/5 1mbps 1 max3232e +3.0 to +5.5 2/2 250 300 max3222e +3.0 to +5.5 2/2 250 300 max3223e +3.0 to +5.5 2/2 250 1 max3224e +3.0 to +5.5 2/2 250 1 max3225e +3.0 to +5.5 2/2 1mbps 1 MAX3221E +3.0 to +5.5 1/1 250 1 max3227e +3.0 to +5.5 1/1 1mbps 1 max3226e +3.0 to +5.5 1/1 250 1 auto- shutdown plus yes yes yes yes yes yes auto- shutdown yes yes yes human body model (kv) ?5 ?5 ?5 ?5 ?5 ?5 ?5 ?5 ?5 ?5 ?5 ?5 iec 1000-4-2 contact discharge (kv) ? ? ? ? ? ? ? ? ? ? ? ? iec 1000-4-2 air-gap discharge (kv) ?5 ?5 ?5 ?5 ?5 ?5 ?5 ?5 ?5 ?5 ?5 ?5
MAX3221E/max3223e/max3243e 15kv esd-protected, 1a, 3.0v to 5.5v, 250kbps, rs-232 transceivers with autoshutdown ______________________________________________________________________________________ 13 figure 11. loopback test result at 250kbps 2 s/div t1in t1out r1out 5v/div 5v/div 5v/div v cc = 3.3v compatible with act and hct cmos, and with ttl. incompatible with ac, hc, or cd4000 cmos. 3.3 5 system power- supply voltage (v) compatible with all ttl and cmos-logic families. 5 5 compatible with all cmos families. 3.3 3.3 compatibility v cc supply voltage (v) table 5. logic family compatibility with various supply voltages interconnection with 3v and 5v logic the MAX3221E/max3223e/max3243e can directly inter- face with various 5v logic families, including act and xhct cmos. see table 5 for more information on possi- ble combinations of interconnections. figure 12a. transmitter output voltage vs. load current per transmitter -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 012345678910 max2343e-fig15 load current per transmitter (ma) transmitter output voltage (v) v out+ v out- v out+ v out- v cc v cc = 3.0v ___________________chip information MAX3221E transistor count: 269 max3223e transistor count: 339 max3243e transistor count: 476
MAX3221E/max3223e/max3243e 15kv esd-protected, 1a, 3.0v to 5.5v, 250kbps, rs-232 transceivers with autoshutdown 14 ______________________________________________________________________________________ +v computer serial port +v -v gnd tx serial mouse max3243e forceoff 23 r5out 15 r4out 16 r3out 17 r2out 18 r1out 19 r2outb 20 logic outputs 5k ? 5k ? 5k ? 5k ? 5k ? r5in 8 r4in 7 r3in 6 r2in 5 r1in 4 rs-232 inputs gnd 25 logic inputs t3in 12 t2in 13 t1in 14 c2- 2 c2+ 1 c1- 24 c1+ 28 t3out 11 t2out 10 t1out 9 v- 3 v+ 27 v cc v cc v cc c4 0.1 f c3 0.1 f 0.1 f 26 c1 0.1 f c2 0.1 f forceon invalid 22 21 to power- management unit +3.3v figure 12b. mouse driver test circuit
MAX3221E/max3223e/max3243e 15kv esd-protected, 1a, 3.0v to 5.5v, 250kbps, rs-232 transceivers with autoshutdown ______________________________________________________________________________________ 15 typical operating circuits max3223e forceon en 14 1 r2out 10 r1out 15 forceoff 20 invalid 11 r2in 9 gnd 18 rs-232 outputs ttl/cmos inputs t2in 12 t1in 13 c2- 6 c2+ 5 c1- 4 c1+ 2 r1in 16 t2out 8 t1out 17 v- 7 v+ 3 v cc v cc c4 0.1 f c3 0.1 f 0.1 f 19 c1 0.1 f c2 0.1 f c bypass +3.3v rs-232 inputs to power- management unit ttl/cmos outputs 5k ? 5k ? max3243e forceoff 23 r5out 15 r4out 16 r3out 17 r2out 18 r1out 19 r2outb 20 logic outputs 5k ? 5k ? 5k ? 5k ? 5k ? r5in 8 r4in 7 r3in 6 r2in 5 r1in 4 rs-232 inputs gnd 25 rs-232 outputs logic inputs t3in 12 t2in 13 t1in 14 c2- 2 c2+ 1 c1- 24 c1+ 28 t3out 11 t2out 10 t1out 9 v- 3 v+ 27 v cc c bypass v cc c4 0.1 f c3 0.1 f 0.1 f 26 c1 0.1 f c2 0.1 f forceon invalid 22 21 to power- management unit +3.3v MAX3221E forceon en 12 1 r1out 9 forceoff 16 invalid 10 gnd 14 t1in 11 c2- 6 c2+ 5 c1- 4 c1+ 2 r1in 8 t1out 13 v- 7 v+ 3 v cc v cc c4 0.1 f c3 0.1 f 0.1 f 15 c1 0.1 f c2 0.1 f c bypass +3.3v to power- management unit 5k ?
MAX3221E/max3223e/max3243e 15kv esd-protected, 1a, 3.0v to 5.5v, 250kbps, rs-232 transceivers with autoshutdown maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim product. no circu it patent licenses are implied. maxim reserves the right to change the circuitry and specifications without notice at any time. 16 ____________________maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 2002 maxim integrated products printed usa is a registered trademark of maxim integrated products. pin configurations 20 19 18 17 16 15 14 13 1 2 3 4 5 6 7 8 forceoff v cc gnd t1out c1- v+ c1+ en r1in r1out forceon t1in t2out v- c2- c2+ 12 11 9 10 t2in invalid r2out r2in dip/ssop/tssop max3223e 28 27 26 25 24 23 22 21 20 19 18 17 16 15 1 2 3 4 5 6 7 8 9 10 11 12 13 14 c1+ v+ v cc gnd c1- forceon forceoff invalid r2outb r1out r2out r3out r4out r5out c2+ c2- v- r1in r2in r3in r4in r5in t1out t2out t3out t3in t2in t1in so/ssop/tssop max3243e top view 16 15 14 13 12 11 10 9 1 2 3 4 5 6 7 8 en c1+ v+ c1- c2+ c2- v- r1in forceoff v cc gnd t1out forceon t1in invalid r1out MAX3221E ssop

▲Up To Search▲

Price & Availability of MAX3221E

	To Download MAX3221E Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .