View MAX3173CAI-T_9089532.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

general description the max3171/max3173 are three-driver/three-receivermultiprotocol transceivers that operate from a single +3.3v supply. the max3171/max3173, along with the max3170 and max3172/max3174, form a complete software-selectable data terminal equipment (dte) or data communications equipment (dce) interface port that supports v.28 (rs-232) and v.10/v.11 (rs-449, v.36, eia-530, eia-530-a, x.21, rs-423) protocols. the max3171/max3173 transceivers carry the serial inter- face control signaling; the max3170 transceivers carry the clock and data signals. the max3172/ max3174 have an extra transceiver for applications requiring four transceivers for control signaling. an internal charge pump and proprietary low-dropout transmitter output stage allow v.28, v.11, and v.10 compliant operation from a single +3.3v supply. a no- cable mode is entered when all mode pins (m0, m1, and m2) are pulled high or left unconnected. in no- cable mode, supply current decreases to 2ma and all transmitter and receiver outputs are disabled (high impedance). short-circuit limiting and thermal-shut- down circuits protect the drivers against excessive power dissipation. the max3171 features 10? deglitching on the v.10/v.11/v.28 receiver inputs. the max3173 is avail- able for applications that do not require deglitching on the serial handshake signals. these parts require only four surface-mount capacitors for charge-pump operation in addition to supply bypassing. features ? industry? first +3.3v multiprotocol transceiver ? certified tbr-1 and tbr-2 compliant (net1 and net2) ? supports v.28 (rs-232) and v.10/v.11 (rs-449,v.36, eia-530, eia-530-a, x.21, rs-423) protocols ? 3v/5v logic compatibility ? software-selectable dce/ dte ? true fail-safe receiver operation ? available in small 28-pin ssop package ? 10? receiver input deglitching (max3171 only) ? all transmitter outputs fault protected to ?5v,tolerate cable miswiring ________________________applications data networking pci cards csu and dsu telecommunications data routers max3171/max3173 +3.3v multiprotocol 3tx/3rx software-selectable control transceivers ________________________________________________________________ maxim integrated products 1 19-1703; rev 1; 8/01 ordering information part temp. range pin-package max3171 cai 0 c to +70 c 28 ssop max3173 cai 0 c to +70 c 28 ssop d1 d2 d3 r1 r2 r3 max3170 rxd rxc txd txc scte d1 r4 d4 d2 d3 r1 r2 r3 max3171max3173 max3172max3174 cts dsr rts dtr ll dcd cts bcts a dsr bdsr a dcd bdcd a dtr bdtr a rts brts a shield sg ll a rxd a rxd brxc b rxc a txc btxc a scte bscte a txd btxd a db-25 connector 13 5 10 8 22 6 23 20 19 4 1 7 16 18 3 9 17 12 15 11 24 14 2 typical operating circuit pin configuration appears at end of data sheet 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. downloaded from: http:///
max3171/max3173 +3.3v multiprotocol 3tx/3rx software-selectable control transceivers 2 _______________________________________________________________________________________ absolute maximum ratings electrical characteristics(v cc = 3.3v ?%; c1 = c2 = 1?, c3 = c4 = c5 = 3.3?, and t a = t min to t max , unless otherwise noted. typical values are at v cc = +3.3v, t a = +25 c.) (note 2) stresses beyond those listed under ?bsolute maximum ratings?may cause permanent damage to the device. these are stress ratings 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. note 1: v+ and v- can have maximum magnitudes of 7v, but their absolute difference cannot exceed 13v. (all voltages referenced to gnd unless otherwise noted.)supply voltages v cc ......................................................................-0.3v to +4v v+ (note 1) ..........................................................-0.3v to +7v v- (note 1) ...........................................................+0.3v to -7v v+ to v- (note 1) ...............................................................13v logic input voltages m0, m1, m2, dce/ dte, t_in ...............................-0.3v to +6v logic output voltages r_out ...................................................-0.3v to (v cc + 0.3v) short-circuit duration............................................continuous transmitter outputs t_out_...............................................................-15v to +15v short-circuit duration ........................................................60s receiver inputs r_in_ ..................................................................-15v to +15v continuous power dissipation (t a = +70?) 28-pin ssop (derate 11.1mw/? above +70?) ........889mw operating temperature range max3171cai/max3173cai ...............................0? to +70? storage temperature range ............................-65? to +150? lead temperature (soldering, 10s) ................................+300? parameter symbol conditions min typ max units dc characteristics v.11/v.10 modes 220 300 v.11/v.10 modes (no load) 6 23 v.28 mode 24 40 v.28 mode (no load) 6 23 supply current(dce mode, digital inputs = gnd or v cc , transmitter outputs static) i cc no-cable mode 2 8 ma v.11/v.10 modes (no load) 20 v.11/v.10 modes (full load) 450 v.28 mode (full load) 40 internal power dissipation p d no-cable mode 6.6 mw v.11/v.10 modes (no load) 4.4 v.11/v.10 modes (full load) 4.2 v.28 mode 5.55 v+ output voltage v+ no-cable mode 4.6 v v.11/v.10 modes (no load) -4.0 v.11/v.10 modes (full load) -3.8 v.28 mode -5.45 v- output voltage v- no-cable mode -4.2 v charge-pump enable time delay until v+ and v- specifications met 1 ms logic inputs (m0, m1, m2, dce/ dte , t_in) input high voltage v ih 2.0 v input low voltage v il 0.8 v t_in 1 m0, m1, m2, dce / dte = v cc 1 logic input current i ih , i il m0, m1, m2, dce / dte = gnd 30 50 100 ? downloaded from: http:///
max3171/max3173 +3.3v multiprotocol 3tx/3rx software-selectable control transceivers _______________________________________________________________________________________ 3 electrical characteristics (continued)(v cc = 3.3v ?%; c1 = c2 = 1?, c3 = c4 = c5 = 3.3?, and t a = t min to t max , unless otherwise noted. typical values are at v cc parameter symbol conditions min typ max units logic outputs (r_out) output high voltage v oh i source = 1.0ma v cc - 1.0 v output low voltage v ol i sink = 1.6ma 0.4 v rise or fall time t r , t f 10% to 90%, figure 4 15 ns r_out = gnd 30 50 100 output leakage current(receiver output three-stated) r_out = v cc 1 ? transmitter outputs output leakage current i z -0.25v v out +0.25v, power off or no-cable mode -100 100 ? v.28 240 v.10 115 kbps data rate v.11 10 mbps minimum pulse width passed 5 receiver glitch rejection(max3171 only) minimum pulse width rejected 15 ? -10v v ab +10v, v a or v b grounded, v.11/v.35, no-cable mode 20 40 receiver input resistance r in -15v v a +15v, v.28 mode 3 5 7 k v.10/v.28 64 max3171 v.11 64 v.10/v.28 240 kbps data rate max3173 v.11 10 mbps v.11 transmitter unloaded differential outputvoltage v odo r = 1.95k , figure 1 4.0 6.0 v loaded differential outputvoltage v odl r = 50 , figure 1 0.5 ? v odo v change in magnitude of outputdifferential voltage ? v od r = 50 , figure 1 0.2 v common-mode output voltage v oc r = 50 , figure 1 3.0 v change in magnitude of outputcommon-mode voltage ? v oc r = 50 , figure 1 0.2 v short-circuit current i sc t_outa/b = gnd 60 150 ma rise or fall time t r , t f 10% to 90%, figure 2 10 25 ns transmitter input to output t phl , t plh figure 2 50 80 ns data skew | t phl - t plh | figure 2 2 10 ns output-to-output skew t skew figure 2 2 ns channel-to-channel skew 2n s v.11 receiver differential threshold voltage v th -7v v cm +7v -200 -100 -25 mv input hysteresis ? v th -7v v cm +7v 5 15 mv downloaded from: http:///
max3171/max3173 +3.3v multiprotocol 3tx/3rx software-selectable control transceivers 4 _______________________________________________________________________________________ parameter symbol conditions min typ max units max3171 5 10 15 s receiver input to output t phl , t plh max3173 60 120 ns max3171 0.5 4 ? data skew | t p h l - t p lh | max3173 5 16 ns v.10 transmitter unloaded output voltage v odo r l = 3.9k , figure 3 4.0 4.4 6.0 v loaded output voltage swing v odl r l = 450 , figure 3 0.9 ? v odo v short-circuit current i sc t_outa = gnd 100 150 ma transmitter rise or fall time t r , t f r l = 450 , c l = 100pf, figure 3 2 ? transmitter input to output t phl , t plh r l = 450 , c l = 100pf, figure 3 2 ? data skew | t p h l - t p lh | r l = 450 , c l =100pf, figure 3 50 ns v.10 receiver threshold voltage v th +25 +100 +300 mv input hysteresis ? v th 15 mv max3171, figure 4 5 10 15 ? receiver input to output t phl , t plh max3173, figure 4 60 120 ns max3171, figure 4 0.5 4 s data skew | t p h l - t p lh | max3173, figure 4 5 16 ns v.28 transmitter all transmitters loaded with r l = 3k ? 5.0 5.4 output voltage swing v o no load 6.5 v short-circuit current i sc t_outa = gnd 25 60 ma r l = 3k , c l = 2500pf, measured from +3v to -3v or from -3v to +3v, figure 3 43 0 output slew rate sr r l = 7k , c l = 150pf, measured from +3v to -3v or from -3v to +3v, figure 3 63 0 v/? transmitter input to output t phl , t plh figure 3 1 ? data skew | t p h l - t p lh | figure 3 100 ns v.28 receiver input threshold low v il 0.8 v input threshold high v ih 2.0 v input hysteresis v hys 0.5 v max3171, figure 4 5 10 15 propagation delay t plh , t phl max3173, figure 4 200 ? max3171, figure 4 0.5 4.0 s data skew | t p h l - t p lh | max3173, figure 4 100 ns electrical characteristics (continued)(v cc = 3.3v ?%; c1 = c2 = 1?, c3 = c4 = c5 = 3.3?, and t a = t min to t max , unless otherwise noted. typical values are at v cc = +3.3v, t a = +25 c.) (note 2) note 2: v+ and v- are also used to supply the max3172/max3174. the max3171/max3173 are tested with additional current load on v+ and v- to capture the effect of loading from the max3172/max3174 in all operation modes. downloaded from: http:///
max3171/max3173 +3.3v multiprotocol 3tx/3rx software-selectable control transceivers _______________________________________________________________________________________ 5 0 50 150100 200 250 v.10/v.11 mode supply current vs. data rate max3171 toc01 data rate (kbps) supply current (ma) 0.001 0.01 10k 100k 0.1 1k 1000k no load full load 0 10 4030 20 6050 8070 v.28 mode supply current vs. data rate max3171 toc02 data rate (kbps) supply current (ma) 0.001 0.01 10k 100k 0.1 1k 1000k full load no load -4 -3 -2 -1 0 1 2 3 4 -40 -15 10 35 60 85 v.11 loaded differential output voltage vs. temperature max3171 toc03 temperature ( c) output voltage (v) v out+ v out- r l = 100 typical operating characteristics (v cc = +3.3v, c1 = c2 = 1.0?, c3 = c4 = c5 = 3.3?, t a = +25 c, unless otherwise noted.) -8 -6 -4 -2 0 2 4 6 8 -40 -15 10 35 60 85 v.28 loaded output voltage vs. temperature max3171 toc04 temperature ( c) output voltage (v) v out+ v out- r l = 3k -5 -2-3 -4 -1 0 1 2 3 4 5 -40 10 - 1 5 3 56 08 5 v.10 loaded output voltage vs. temperature max3171 toc05 temperature ( c) output voltage (v) v out+ v out- r l = 450 -0.3 -0.1-0.2 0.1 0 0.2 0.3 -10 0 -5 5 10 v.10/v.11 receiver input current vs. input voltage max3171 toc06 input voltage (v) input current (ma) -4 -3 -2 -1 0 1 2 3 4 -15 -5 -10 0 5 10 15 v.28 receiver input current vs. input voltage max3171 toc07 input voltage (v) input current (ma) 0 42 10 86 1614 12 18 0 1000 500 1500 2000 2500 3000 v.28 slew rate vs. load capacitance max3171toc11 capacitance (pf) slew rate (v/ s) +slew -slew 0 0.5 1.51.0 2.0 2.5 0 1000 500 1500 2000 2500 3000 v.10 transmitter rise and fall times vs. load capacitance max3171toc12 capacitance (pf) rise/fall time ( s) fall rise downloaded from: http:///
max3171/max3173 +3.3v multiprotocol 3tx/3rx software-selectable control transceivers 6 _______________________________________________________________________________________ typical operating characteristics (continued) (v cc = +3.3v, c1 = c2 = 1.0?, c3 = c4 = c5 = 3.3?, t a = +25 c, unless otherwise noted.) tin2 tout2/ rin2 rout2 5v/div 10 s/div max3173 loopback scope photo 530a mode (unloaded) max3171 toc10 tin tout/ rin rout 5v/div 10 s/div max3173 loopback scope photo v.11 mode (unloaded) max3171 toc08 tin tout/ rin rout 5v/div 10 s/div max3171 loopback scope photo v.28 mode (r l = 3k ) max3171 toc09 figure 1. v.11 dc test circuit figure 2. v.11 ac test circuit 100pf 50pf 100pf 100 rx tx test circuits v oc rr v od downloaded from: http:///
max3171/max3173 +3.3v multiprotocol 3tx/3rx software-selectable control transceiver _______________________________________________________________________________________ 7 pin description pin name function 1v + positive supply generated by the charge pump (connect to v+ pin of max3172/max3174).bypass v+ to ground with a 3.3? ceramic capacitor. 2 c2+ positive terminal of the inverting charge-pump capacitor. connect c2+ to c2- with a 1?ceramic capacitor. 3c 2 - negative terminal of the inverting charge-pump capacitor. connect c2+ to c2- with a 1?ceramic capacitor. 4v - negative supply generated by the charge pump (connect to v- pin of max3172/max3174).bypass v- to ground with a 3.3? ceramic capacitor. 5, 6, 7 t_in transmitter cmos inputs (t1in, t2in, t3in) 8, 9, 10 r_out receiver cmos outputs (r1out, r2out, r3out) 11, 12, 13 m_ mode select inputs (m0, m1, m2). internally pulled up to v cc . see table 1 for detailed information. 14 dce/ dte dce/ dte mode select input. logic level high selects dce interface; logic level low selects dte interface. internally pulled up to v cc . 15, 18 r_inb noninverting receiver inputs (r3inb, r2inb) 16, 17 r_ina inverting receiver inputs (r3ina, r2ina) 19 t3outb/r1inb noninverting transmitter output/noninverting receiver input 20 t3outa/r1ina inverting transmitter output/inverting receiver input 21, 23 t_outb noninverting transmitter outputs (t2outb, t1outb) 22, 24 t_outa inverting transmitter outputs (t2outa, t1outa) 25 c1- negative terminal of the voltage-doubler charge-pump capacitor. connect c1+ to c1- witha 1? ceramic capacitor. 26 gnd ground 27 v cc +3.3v supply voltage (?%). bypass v cc to ground with a 3.3? ceramic capacitor. 28 c1+ positive terminal of the voltage-doubler charge-pump capacitor. connect c1+ to c1- with a 1? ceramic capacitor. figure 3. v.10/v.28 driver test circuit r l c l tx figure 4. v.10/v.28 receiver test circuit test circuits (continued) 50pf tx rx downloaded from: http:///
max3171/max3173 +3.3v multiprotocol 3tx/3rx software-selectable control transceivers 8 _______________________________________________________________________________________ detailed description the max3171/max3173 are three-driver/three-receivermultiprotocol transceivers that operate from a single +3.3v supply. the max3171/max3173, along with the max3170 and max3172/max3174, form a complete software-selectable dte or dce interface port that sup- ports the v.28 (rs-232), v.10/v.11 (rs-449, v.36, eia- 530, eia-530-a, x.21, rs-423), and v.35 protocols. the max3171/max3173 carry the control signals, while the max3170 transceiver carries the high-speed clock and data signals. the max3172/max3174 provide termina- tion for the clock and data signals and have an extra transceiver for applications requiring four transceivers for control handshaking. the max3171/max3173 feature a 2ma no-cable mode,true fail-safe operation, and thermal shutdown circuitry. thermal shutdown protects the drivers against exces- sive power dissipation. when activated, the thermal shutdown circuitry places the driver outputs into a high- impedance state. mode selection the state of mode select pins m0, m1, and m2 determines which serial interface protocol is selected (table 1). the state of the dce/ dte input determines whether the trans- ceivers will be configured as a dte serial port or a dce serial port. when the dce/ dte input is logic high, dri- ver t3 is activated and receiver r1 is disabled. when the dce/ dte input is logic low, driver t3 is disabled and receiver r1 is activated. m0, m1, m2, anddce/ dte are internally pulled up to v cc to ensure logic high if left unconnected. the max3171/max3173 s mode can be selected through software control of the m0, m1, m2, anddce/ dte inputs. alternatively, the mode can be select- ed by shorting the appropriate combination of modecontrol inputs to gnd (the inputs left floating will be internally pulled up to v cc ). if the m0, m1, and m2 mode inputs are all unconnected, the max3171/max3173 will enter no-cable mode. table 1. mode selection logic inputs transmitters receivers protocol m2 m1 m0 dce/ dte t1 t2 t3 r1 r2 r3 v.11 0 0 0 0 v.11 v.11 z v.11 v.11 v.11 rs-530a 0 0 1 0 v.11 v.10 z v.11 v.10 v.11 rs-530 0 1 0 0 v.11 v.11 z v.11 v.11 v.11 x.21 0 1 1 0 v.11 v.11 z v.11 v.11 v.11 v.35 1 0 0 0 v.28 v.28 z v.28 v.28 v.28 rs-449/v.36 1 0 1 0 v.11 v.11 z v.11 v.11 v.11 v.28/rs-232 1 1 0 0 v.28 v.28 z v.28 v.28 v.28 no cable 1 1 1 0 zzzzzz v.11 0 0 0 1 v.11 v.11 v.11 z v.11 v.11 rs-530a 0 0 1 1 v.11 v.10 v.11 z v.10 v.11 rs-530 0 1 0 1 v.11 v.11 v.11 z v.11 v.11 x.21 0 1 1 1 v.11 v.11 v.11 z v.11 v.11 v.35 1 0 0 1 v.28 v.28 v.28 z v.28 v.28 rs-449/v.36 1 0 1 1 v.11 v.11 v.11 z v.11 v.11 v.28/rs-232 1 1 0 1 v.28 v.28 v.28 z v.28 v.28 no cable 1 1 1 1 zzzzzz 12 2827 v cc gnd c1+ 34 2625 max3171max3173 c1- c2- v- v+ c2+ c2 1 f c53.3 f c11 f c3 3.3 f c4 3.3 f figure 5. charge-pump connections z = high impedance downloaded from: http:///
max3171/max3173 +3.3v multiprotocol 3tx/3rx software-selectable control transceiver _______________________________________________________________________________________ 9 no-cable mode the max3171/max3173 enter no-cable mode when themode select pins are left unconnected or tied high (m0 = m1 = m2 = 1). in this mode, the multiprotocol dri- vers and receivers are disabled and the supply current is less than 8ma. the receiver outputs enter a high- impedance state in no-cable mode, which allows these output lines to be shared with other receivers (the receiver outputs have an internal pullup resistor to pull the outputs high if not driven). also, in no-cable mode, the transmitter outputs enter a high-impedance state, so these output lines can be shared with other devices. dual charge-pump voltage converter the max3171/max3173 internal power supply consistsof a regulated dual charge pump that provides positive and negative output voltages from a +3.3v supply. the charge pump operates in discontinuous mode: if the out- put voltage is less than the regulated voltage, the charge pump is enabled; if the output voltage exceeds the regu- lated voltage, the charge pump is disabled. each charge pump requires a flying capacitor (c1, c2) and a reser- voir capacitor (c3, c4) to generate the v+ and v- sup- plies. see figure 5 for charge-pump connections. the charge pump is designed to supply v+ and v- power to the max3172/max3174 in addition to the max3171/max3173 internal transceivers. connect the max3172/max3174 v+ and v- terminals to the max3171/max3173 v+ and v- terminals, respectively. fail-safe the max3171/max3173 guarantee a logic highreceiver output when the receiver inputs are shorted or open, or when they are connected to a terminated transmission line with drivers disabled. the v.11 receiv- er threshold is set between -25mv and -200mv to guar- antee fail-safe operation. if the differential receiver input voltage (b - a) is -25mv, r_out is logic high. in the case of a terminated bus with all transmitters disabled,the receiver s differential input voltage is pulled to 0 by the termination. with the max3171/max3173 receiverthresholds, this results in r_out logic high with a 25mv (min) noise margin. the v.10 receiver threshold is set between +25mv and +300mv. if the v.10 receiver input voltage is +25mv, rout is logic high. the v.28 receiver threshold is setbetween 0.8v and 2.0v. if the receiver input voltage is 0.8v, rout is logic high. in the case of a terminated bus with transmitters disabled, the v.10/v.28 receiver s input voltage is pulled to ground by the termination.with the max3172/max3174 receiver thresholds, this results in r_out logic high. applications information capacitor selection the capacitors used for the charge pumps, as well asthe supply bypassing, should have a low-esr and low- temperature coefficient. multilayer ceramic capacitors with an x7r dielectric offer the best combination of per- formance, size, and cost. the flying capacitors (c1, c2) should have a value of 1?, while the reservoir capacitors (c3, c4) and bypass capacitor (c5) should have a minimum value of 3.3? (figure 5). to reduce the ripple present on the transmitter outputs, capacitors c3, c4, and c5 can be increased. do not increase the value of c1 and c2. local loopback control signal for applications that require the use of local loopback(ll) signal routing, an extra transceiver is available for use on the max3172/max3174 multiprotocol termina- tion network device. cable-selectable mode figure 6 shows a cable-selectable mulitprotocol inter- face. the mode control lines (m0, m1, m2, and dce/ dte ) are wired to the db-25 connector. to select the serial interface mode, the appropriate combinationsof m0, m1, m2, and dce/ dte are grounded within the cable wiring. the control lines that are not groundedare pulled high by the internal pullups on the max3170. the serial interface protocol of the max3171/max3173 (max3170 and max3172/max3174) is now selected based on the cable connected to the db-25 interface. v.11 (rs-422) interface as shown in figure 7, the v.11 protocol is a fully bal-anced differential interface. the v.11 driver generates ?v (min) between nodes a and b when 100 (min) resistance is presented at the load. the v.11 receiver issensitive to ?00mv differential signals at the receiver inputs a and b . the v.11 receiver input must comply with the impedance curve of figure 8 and reject com- mon-mode signals up to ?v developed across the cable (referenced from c to c in figure 7). the max3171/max3173 v.11 mode receiver has a dif-ferential threshold between -200mv and -25mv to ensure that the receiver has proper fail-safe operation (see fail-safe ). to aid in rejecting system noise, the max3171/max3173 v.11 receiver has a 15mv (typ) hysteresis. switch s3 in figure 9 is open in v.11 mode to disable the v.28 5k termination at the inverting receiver input. because the control signals are slow(64kbps), 100 termination resistance is generally not required for the max3171/max3173. downloaded from: http:///
max3171/max3173 +3.3v multiprotocol 3tx/3rx software-selectable control transceivers 10 ______________________________________________________________________________________ v.10 interface the v.10 interface (figure 10) is an unbalanced single-ended interface capable of driving a 450 load. the v.10 driver generates a ?v (min) v odo voltage across a' and c' when unloaded and a minimum of ?.9 ? v odo voltage with a 450 load. the v.10 receiver input trip threshold is defined between +300mv and -300mvwith the input impedance characteristic shown in figure 8. the max3171/max3173 v.10 mode receiver has a threshold between +25mv and +300mv to ensure that the receiver has proper fail-safe operation (see fail- d1 d2 d3 r1 r2 r3 max3170 rxd(dte) txd(dce) rxc(dte) scte(dce) txd(dte) rxd(dce) txc(dte) txc(dce) scte(dte) rxc(dce) m1m2 m0dce/dte d1 r4 d4 d2 d3 r1 r2 r3 max3171max3173 m1m2 m0dce/dte cts(dte) rts(dce) dsr(dte) dtr(dce) rts(dte) cts(dce) dtr(dte) dsr(dce) dcd(dte) dcd(dce) m2 m1 m0 m1 m0 dce/dte dce/dte cts bcts a dsr dsr dcd dcd dtr b dtr a rts b rts a shield sg rxdrxd rxc rxc txc btxc a scte bscte a txd btxd a db-25 connector dte dce rts brts a dtr bdtr a dcddcd dsrdsr cts bcts a txd btxd a scte bscte a txc btxc a rxcrxc rxd rxd cable wiring for mode selection modev.35 rs-449, v.36 rs-232 pin 18pin 7 n.c. pin 7 pin 21pin 7 pin 7 n.c. cable wiring for dce/dte selection modedte dce pin 25pin 7 n.c. 13 5 10 8 22 6 23 20 19 4 1 7 18 21 25 16 3 9 17 12 15 11 24 14 2 v cc max3172max3174 figure 6. cable-selectable multiprotocol dce/dte port figure 7. typical v.11 interface 100 min a b c ab c generator balanced interconnecting cable cable termination receiver load downloaded from: http:///
max3171/max3173 +3.3v multiprotocol 3tx/3rx software-selectable control transceiver ______________________________________________________________________________________ 11 r6 10k r8 5k a b c ab gnd r5 30k r7 10k r4 30k s4 s5 max3171max3173 s3 receiver figure 12. v.28 termination and internal resistance networks figure 11. v.10 internal resistance network r6 10k r85k a b c ab gnd r5 30k r7 10k r4 30k max3171max3173 s3 receiver figure 10. typical v.10/v.28 interface figure 9. v.11 termination and internal resistance networks r6 10k r85k a b c ab gnd r5 30k r710k r4 30k max3171max3173 s3 receiver figure 8. receiver input impedance curve -3.25ma 3.25ma -10v +10v -3v +3v v z i z a c a c generator unbalanced interconnecting cable cable termination receiver load downloaded from: http:///
max3171/max3173 +3.3v multiprotocol 3tx/3rx software-selectable control transceivers 12 ______________________________________________________________________________________ safe ). to aid in rejecting system noise, the max3171/max3173 v.10 receiver has 15mv (typ) hys-teresis. switch s3 in figure 11 is open in v.10 mode to disable the 5k v.28 termination at the receiver input. switch s4 is closed, and switch s5 is open to internallyground the receiver b input. v.28 interface the v.28 interface is an unbalanced single-ended inter-face (figure 12). the v.28 generator provides ?v (min) across the load impedance between a and c . the v.28 standard specifies input trip points at ?v.the max3171/max3173 v.28 mode receiver has a threshold between +0.8v and +2.0v to ensure that the receiver has proper fail-safe operation (see fail-safe ). to aid in rejecting system noise, the max3171/max3173v.28 receiver has a 500mv (typ) hysteresis. switch s3 in figure 12 is closed in v.28 mode to enable the 5k v.28 termination at the receiver input. receiver glitch rejection to facilitate operation in an unterminated or otherwisenoisy system, the max3171 features 10? of receiver input glitch rejection in v.10, v.11, and v.28 modes. the glitch rejection circuitry blocks the reception of high-frequency noise (t b < 5?) while receiving a low- frequency signal (t b > 15?), allowing glitch-free opera- tion in unterminated systems at up to 64kbps. themax3173 does not have this feature and can be oper- ated at data rates up to 240kbps if properly terminated. dte vs. dce operation figure 13 shows a dce or dte controller-selectable interface. the dce/ dte input switches the port s mode of operation. a logic high selects dce, which enables figure 13. multiprotocol dce/ dte port d1 d2 d3 r1 r2 r3 max3170 rxd(dte) txd(dce) rxc(dte) scte(dce) ll(dte) ll(dce) txd(dte) rxd(dce) txc(dte) txc(dce) scte(dte) rxc(dce) m1m2 m0dce/dte m1m2 m0 dce/dte d1 r4 d4 d2 d3 r1 r2 r3 max3171max3173 m1m2 m0dce/dte cts(dte) rts(dce) dsr(dte) dtr(dce) rts(dte) cts(dce) dtr(dte) dsr(dce) dcd(dte) dcd(dce) m2 m1 m0 dce/dte cts bcts a dsr bdsr a dcd bdcd a dtr bdtr a rts brts a shield sg ll a rxd brxd a rxc b rxc a txc btxc a scte bscte a txd btxd a db-25 connector dte dce rts brts a dtr bdtr a dcd bdcd a dsr bdsr a cts bcts a ll a txd btxd a scte bscte a txc btxc a rxc brxc a rxd b rxd a 13 5 10 8 22 6 23 20 19 4 1 7 18 16 3 9 17 12 15 11 24 14 2 max3172max3174 downloaded from: http:///
driver 3 on the max3171/max3173, driver 3 on themax3170, and driver 4 on the max3172/max3174. a logic low selects dte, which enables receiver 1 on the max3171/max3173, receiver 1 on the max3170, and receiver 4 on the max3172/max3174. this application requires only one db-25 connector. see figure 13 for complete signal routing in dce and dte modes. for example, driver 3 routes the dcd (dce) sig- nal to pins 22 and 6 in dce mode, while in dte mode, receiver 1 routes pins 22 and 6 to dcd (dte). complete multiprotocol x.21 interface figure 14 shows a complete dce-to-dte interface operating in x.21 mode. the max3171/max3173 gen- erate the control signals, and the max3170 is used to generate the clock and data signals. the max3172/ max3174 generate local loopback and are used to ter- minate the clock and data signals to support the v.11 protocol for cable termination. the control signals do not need external termination. max3171/max3173 +3.3v multiprotocol 3tx/3rx software-selectable control transceiver ______________________________________________________________________________________ 13 d1d2 d3 r3r2 r1 d3d2 d1 d4 txd scte txc rxcrxd ll d4 r4 r4 r1r2 r3 103 103 103 103 103 max3170 max3172max3174 max3172max3174 max3170 d1d2 d3 r3r2 r1 d3d2 d1 rts dtr dcd dsr cts r1r2 r3 max3171max3173 max3171max3173 serial controller txd scte txc rxcrxd rts dtr dcd dsr cts ll serial controller txdscte txc rxc rxd rts dtr dcd dsr cts ll dce dte figure 14. dce-to-dte x.21 interface downloaded from: http:///
compliance testing a european standard en 45001 test report is availablefor the max3170 max3174 chipset. a copy of the test report will be available from maxim. pin configuration 2827 26 25 24 23 22 21 20 19 18 17 16 15 12 3 4 5 6 7 8 9 1011 12 13 14 c1+v cc gndc1- t1outa t1outb r3inb t2outat2outb t3outa/r1ina t3outb/r1inb r2inb r2ina r3ina dce/dte m2 m1 m0 r3out r2out r1out t3in t2in t1in v- c2- c2+ v+ ssop top view max3171max3173 chip information transistor count: 1763 process: bicmos max3171/max3173 +3.3v multiprotocol 3tx/3rx software-selectable control transceivers 14 ______________________________________________________________________________________ downloaded from: http:///
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. maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 ____________________ 15 2001 maxim integrated products printed usa is a registered trademark of maxim integrated products. package information ssop.eps max3171/max3173 +3.3v multiprotocol 3tx/3rx software-selectable control transceiver downloaded from: http:///

▲Up To Search▲

Price & Availability of MAX3173CAI-T

	To Download MAX3173CAI-T Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .