general description the max9123 quad low-voltage differential signaling(lvds) differential line driver is ideal for applications requiring high data rates, low power, and low noise. the max9123 is guaranteed to transmit data at speeds up to 800mbps (400mhz) over controlled impedance media of approximately 100 . the transmission media may be printed circuit (pc) board traces, backplanes, or cables. the max9123 accepts four lvttl/lvcmos input levels and translates them to lvds output signals. moreover, the max9123 is capable of setting all four outputs to a high-impedance state through two enable inputs, en and en , thus dropping the device to an ultra-low-power state of 16mw (typ) during high impedance. the enables arecommon to all four transmitters. outputs conform to the ansi tia/eia-644 lvds standard. flow-through pinout simplifies pc board layout and reduces crosstalk by sep- arating the lvttl/lvcmos inputs and lvds outputs. the max9123 operates from a single +3.3v supply and is specified for operation from -40? to +85?. it is available in 16-pin tssop and so packages. refer to the max9121/ max9122* data sheet for quad lvds line receivers with integrated termination and flow-through pinout. applications features ? flow-through pinout simplifies pc board layoutreduces crosstalk ? pin compatible with ds90lv047a ? guaranteed 800mbps data rate ? 250ps maximum pulse skew ? conforms to tia/eia-644 lvds standard ? single +3.3v supply ? 16-pin tssop and so packages max9123 quad lvds line driver with flow-through pinout ________________________________________________________________ maxim integrated products 1 1615 14 13 12 11 10 9 12 34 5 6 7 8 en out1- out1+out2+ out2- out3- out3+ out4+ out4- top view max9123 tssop/so in1in2 in3 v cc gnd in4 en pin configuration ordering information 107 max9123 max9122* 107 107 107 r x lvds signals 100 shielded twisted cable or microstrip pc board traces lvttl/cmos data input lvttl/cmosdata output r x r x r x t x t x t x t x typical applications circuit 19-1927; rev 0; 2/01 for price, delivery, and to place orders, please contact maxim distribution at 1-888-629-4642, or visit maxim? website at www.maxim-ic.com. part temp. range pin-package max9123eue -40 c to +85 c 16 tssop max9123ese -40 c to +85 c 16 so * future product contact factory for availability. digital copierslaser printers cell phone base stations add drop muxes digital cross-connects dslamsnetwork switches/routers backplane interconnect clock distribution downloaded from: http:///
max9123 quad lvds line driver with flow-through pinout 2 _______________________________________________________________________________________ absolute maximum ratings dc electrical characteristics(v cc = +3.0v to +3.6v, r l = 100 ?%, t a = -40 c to +85 c. typical values are at v cc = +3.3v, t a = +25 c, unless otherwise noted.) (notes 1, 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 specifications is not implied. exposure to absolute maximum rating conditions for extended periods may affect device reliability. v cc to gnd ...........................................................-0.3v to +4.0v in_, en, en to gnd....................................-0.3v to (v cc + 0.3v) out_+, out_- to gnd..........................................-0.3v to +3.9v short-circuit duration (out_+, out_-) .....................continuous continuous power dissipation (t a = +70 c) 16-pin tssop (derate 9.4mw/ c above +70 c) .........755mw 16-pin so (derate 8.7mw/ c above +70 c)................696mw storage temperature range .............................-65 c to +150 c maximum junction temperature .....................................+150 c operating temperature range ...........................-40 c to +85 c lead temperature (soldering, 10s) .................................+300 c esd protection human body model, in_, out_+, out_-.......................?kv parameter symbol conditions min typ max units lvds output (out_+, out_-) differential output voltage v od figure 1 250 368 450 mv change in magnitude of v od between complementary outputstates ? v od figure 1 1 35 mv offset voltage v os figure 1 1.125 1.25 1.375 v change in magnitude of v os between complementary outputstates ? v os figure 1 4 25 mv output high voltage v oh 1.6 v output low voltage v ol 0.90 v differential output short-circuitcurrent (note 3) i osd enabled, v od = 0 -9 ma output short-circuit current i os out_+ = 0 at in_ = v cc or out_- = 0 at in_ = 0, enabled -3.8 -9 ma output high-impedance current i oz en = low and en = high, out_+ = 0 or v cc , out_- = 0 or v cc , r l = -10 10 ? power-off output current i off v cc = 0 or open, out_+ = 0 or 3.6v, out_- = 0 or 3.6v, r l = -20 20 ? inputs (in_, en, en ) high-level input voltage v ih 2.0 v cc v low-level input voltage v il gnd 0.8 v input current i in in_, en, en = 0 or v cc -20 20 ? supply current no-load supply current i cc r l = , in_ = v cc or 0 for all channels 9.2 11 ma loaded supply current i ccl r l = 100 , in_ = v cc or 0 for all channels 22.7 30 ma disabled supply current i ccz d i sab l ed , in _ = v c c or 0 for all channel s, e n = 0, en = v cc 4.9 6 ma downloaded from: http:///
max9123 quad lvds line driver with flow-through pinout _______________________________________________________________________________________ 3 switching characteristics(v cc = +3.0v to +3.6v, r l = 100 ?%, c l = 15pf, t a = -40 c to +85 c. typical values are at v cc = +3.3v, t a = +25 c, unless otherwise noted.) (notes 4, 5, 6) parameter symbol conditions min typ max units differential propagation delayhigh to low t phld figures 2 and 3 0.7 1.7 ns differential propagation delaylow to high t plhd figures 2 and 3 0.7 1.7 ns differential pulse skew (note 7) t skd1 figures 2 and 3 0.04 0.25 ns differential channel-to-channelskew (note 8) t skd2 figures 2 and 3 0.07 0.35 ns differential part-to-part skew(note 9) t skd3 figures 2 and 3 0.13 0.8 ns differential part-to-part skew(note 10) t skd4 figures 2 and 3 0.43 1.0 ns rise time t tlh figures 2 and 3 0.2 0.39 1.0 ns fall time t thl figures 2 and 3 0.2 0.39 1.0 ns disable time high to z t phz figures 4 and 5 2.7 5 ns disable time low to z t plz figures 4 and 5 2.7 5 ns enable time z to high t pzh figures 4 and 5 2.3 7 ns enable time z to low t pzl figures 4 and 5 2.3 7 ns maximum operating frequency(note 11) f max 400 mhz note 1: maximum and minimum limits over temperature are guaranteed by design and characterization. devices are 100% tested at t a = +25 c. note 2: currents into the device are positive, and current out of the device is negative. all voltages are referenced to ground except v od . note 3: guaranteed by correlation data. note 4: ac parameters are guaranteed by design and characterization. note 5: c l includes probe and jig capacitance. note 6: signal generator conditions for dynamic tests: v ol = 0, v oh = 3v, f = 100mhz, 50% duty cycle, r o = 50 , t r 1ns, t f 1ns (0% to 100%). note 7: t skd1 is the magnitude difference of differential propagation delay. t skd1 = |t phld - t plhd |. note 8: t skd2 is the magnitude difference of t phld or t plhd of one channel to the t phld or t plhd of another channel on the same device. note 9: t skd3 is the magnitude difference of any differential propagation delays between devices at the same v cc and within 5 c of each other. note 10: t skd4 is the magnitude difference of any differential propagation delays between devices operating over the rated supply and temperature ranges. note 11: f max signal generator conditions: v ol = 0, v oh = 3v, f = 400mhz, 50% duty cycle, r o = 50 , t r 1ns, t f 1ns (0% to 100%). transmitter output criteria: duty cycle = 45% to 55%, v od 250mv. downloaded from: http:///
max9123 quad lvds line driver with flow-through pinout 4 _______________________________________________________________________________________ typical operating characteristics (v cc = +3.3v, r l = 100 , c l = 15pf, t a = +25 c, unless otherwise noted.) 1.090 1.0941.092 1.0981.096 1.100 3.0 3.3 3.6 output high voltage vs. power-supply voltage max9123 toc01 power-supply voltage (v) output high voltage (v) 1.090 1.092 1.0961.094 1.098 1.100 3.0 3.3 3.6 output low voltage vs. power-supply voltage max9123 toc02 power-supply voltage (v) output low voltage (v) -3.650 -3.665-3.660 -3.655 -3.670 -3.675 -3.680 -3.685 -3.690 -3.695 -3.700 3.0 3.3 3.6 output short-circuit current vs. power-supply voltage max9123 toc03 output short-circuit current (ma) power-supply voltage (v) v in = v cc or gnd -250 -200 -100-150 -50 0 3.0 3.3 3.6 max9123 toc04 output high-impedance state current vs. power-supply voltage output high-impedance state current (pa) power-supply voltage (v) v in = v cc or gnd 350 355 360 365 370 375 380 385 390 3.0 3.3 3.6 differential output voltage vs. power supply max9123 toc05 power-supply voltage (v) differential output voltage (v) 300 400350 500450 550 600 90 110 120 100 130 140 150 differential output voltage vs. load resistor max9123 toc06 load resistor ( ) differential output voltage (mv) 1.240 1.244 1.2521.248 1.256 1.260 3.0 3.3 3.6 offset voltage vs. power-supply voltage max9123 toc07 power-supply voltage (v) offset voltage (v) 4020 0.1 10 100 1 1000 power-supply current vs. frequency max9123 toc08 frequency (mhz) power-supply current (ma) 23 25 28 30 33 35 38 v in = 0 to 3v all switching one switching 20.0 22.021.0 23.0 24.0 25.0 3.0 3.3 3.6 power-supply current vs. power-supply voltage max9123 toc09 power-supply voltage (v) power-supply current (ma) freq = 1mhzv in = 0 to 3v downloaded from: http:///
max9123 quad lvds line driver with flow-through pinout _______________________________________________________________________________________ 5 20.0 21.0 23.022.0 24.0 25.0 -40 10 - 1 5 3 56 08 5 power-supply current vs. ambient temperature max9123 toc10 ambient temperature ( c) power-supply current (ma) freq = 1mhzv in = 0 to 3v 1.200 1.4001.350 1.300 1.250 1.5001.450 1.550 1.600 3.0 3.3 3.6 differential propagation delay vs. power supply max9123 toc11 power-supply voltage (v) differential propagation delay (ns) freq = 1mhz t plhd t phld 1.100 1.200 1.4001.300 1.6001.500 -40 10 - 1 5 3 56 08 5 differential propagation delay vs. ambient temperature max9123 toc12 ambient temperature ( c) differential propagation delay (ns) t plhd t phld freq = 1mhz 0 20 40 60 80 100 3.0 3.3 3.6 differential skew vs. power-supply voltage max9123 toc13 power-supply voltage (v) differential skew (ps) freq = 1mhz 0 25 50 100 125 75 150 175 200 -40 10 -15 35 60 85 differential skew vs. ambient temperature max9123 toc14 ambient temperature ( c) differential skew (ps) freq = 1mhz 340 360350 380370 390 400 3.0 3.3 3.6 transition time vs. power-supply voltage max9123 toc15 power-supply voltage (v) transition time (ps) freq = 1mhz t tlh t thl 200 250 300 350 400 450 500 550 600 -40 -15 10 35 60 85 transition time vs. ambient temperature max9123 toc16 ambient temperature ( c) transition time (ps) freq = 1mhz t tlh t thl typical operating characteristics (continued) (v cc = +3.3v, r l = 100 , c l = 15pf, t a = +25 c, unless otherwise noted.) downloaded from: http:///
max9123 quad lvds line driver with flow-through pinout 6 _______________________________________________________________________________________ pin description pin name function 1e n driver enable input. the driver is disabled when en is low. en is internally pulled down. when en =high and en = low or open, the outputs are active. for other combinations of en and en , the outputs are disabled and are high impedance. 2, 3, 6, 7 in_ lvttl/lvcmos driver inputs 4v cc power-supply input. bypass v cc to gnd with 0.1? and 0.001? ceramic capacitors. 5 gnd ground 8 en driver enable input. the transmitter is disabled when en is high. en is internally pulled down. 9, 12, 13, 16 out_- inverting lvds driver outputs 10, 11, 14, 15 out_+ noninverting lvds driver outputs detailed description the lvds interface standard is a signaling methodintended for point-to-point communication over a con- trolled-impedance medium as defined by the ansi/tia/eia-644 and ieee 1596.3 standards. the lvds standard uses a lower voltage swing than other common communication standards, achieving higher data rates with reduced power consumption while reducing emi emissions and system susceptibility to noise. the max9123 is an 800mbps quad differential lvds driver that is designed for high-speed, point-to-point, and low-power applications. this device accepts lvttl/lvcmos input levels and translates them to lvds output signals. the max9123 generates a 2.5ma to 4.0ma output cur- rent using a current-steering configuration. this current- steering approach induces less ground bounce and no shoot-through current, enhancing noise margin and sys- tem speed performance. the driver outputs are short- circuit current limited, and enter a high-impedance state when the device is not powered or is disabled. the current-steering architecture of the max9123 requires a resistive load to terminate the signal and complete the transmission loop. because the device switches current and not voltage, the actual output volt- age swing is determined by the value of the termination resistor at the input of an lvds receiver. logic states are determined by the direction of current flow through the termination resistor. with a typical 3.7ma output current, the max9123 produces an output voltage of 370mv when driving a 100 load. termination because the max9123 is a current-steering device, nooutput voltage will be generated without a termination resistor. the termination resistors should match the dif- ferential impedance of the transmission line. output voltage levels depend upon the value of the termination resistor. the max9123 is optimized for point-to-point interface with 100 termination resistors at the receiver inputs. termination resistance values may rangebetween 90 and132 , depending on the characteris- tic impedance of the transmission medium. applications information power-supply bypassing bypass v cc with high-frequency, surface-mount ceramic 0.1? and 0.001? capacitors in parallel asclose to the device as possible, with the smaller valued capacitor closest to v cc . differential traces output trace characteristics affect the performance ofthe max9123. use controlled-impedance traces to match trace impedance to the transmission medium. enables inputs outputs en en in_ out_+ out_ - h l or open l l h h l or open h h l all other combinations of enable pins don t care zz table 1. input/output function table downloaded from: http:///
max9123 quad lvds line driver with flow-through pinout _______________________________________________________________________________________ 7 eliminate reflections and ensure that noise couples ascommon mode by running the differential trace pairs close together. reduce skew by matching the electrical length of the traces. excessive skew can result in a degradation of magnetic field cancellation. maintain the distance between the differential traces to avoid discontinuities in differential impedance. avoid 90 turns and minimize the number of vias to further prevent impedance discontinuities. cables and connectors transmission media should have a nominal differentialimpedance of 100 . to minimize impedance disconti- nuities, use cables and connectors that have matcheddifferential impedance. avoid the use of unbalanced cables such as ribbon or simple coaxial cable. balanced cables such as twisted pair offer superior signal quality and tend to generate less emi due to canceling effects. balanced cablestend to pick up noise as common mode, which is rejected by the lvds receiver. board layout for lvds applications, a four-layer pc board that pro-vides separate power, ground, lvds signals, and input signals is recommended. isolate the lvttl/lvcmos and lvds signals from each other to prevent coupling. chip information transistor count: 1246process: cmos v os v cc gnd in_ r l /2 r l /2 v os v od out_- out_+ r l c l out_ + out_ - c l 50 in_ generator figure 1. driver v od and v os test circuit figure 2. driver propagation delay and transition time testcircuit 0 v oh v ol in_ out_ - out_+ v diff 3v t phld 1.5v 0 t thl 20% 0 80% 80% 0 t tlh 20% 0 differential t plhd 1.5v v diff = (v out_ +) - (v out_ -) figure 3. driver propagation delay and transition time waveforms downloaded from: http:///
max9123 quad lvds line driver with flow-through pinout 8 _______________________________________________________________________________________ 1.5v en when en = 0 or open en when en = v cc out_+ when in_ = 0 out_- when in_ = v cc out_+ when in_ = v cc out_- when in_ = 0 1.5v 1.5v t plz t phz t pzl t pzh 1.5v 3v0 3v 1.2vv ol v oh 1.2v 0 50% 50% 50% 50% figure 5. driver high-impedance delay waveform en gnd en in_ out_- out_+ 1/4 max9123 generator +1.2v 50 c l r l/2 r l/2 v cc c l figure 4. driver high-impedance delay test circuit out1+out1- out2+ out2- out3+ out3- out4+ out4- enen in1in2 in3 in4 functional diagram downloaded from: http:///
max9123 quad lvds line driver with flow-through pinout _______________________________________________________________________________________ 9 package information tssop,no pads.eps downloaded from: http:///
max9123 quad lvds line driver with flow-through pinout maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim product. no circuit patent licenses are implied. maxim reserves the right to change the circuitry and specifications without notice at any time. 10 ____________________maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 2001 maxim integrated products printed usa is a registered trademark of maxim integrated products. maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim product. no circuit patent licenses are implied. maxim reserves the right to change the circuitry and specifications without notice at any time. 10 ____________________maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 2001 maxim integrated products printed usa is a registered trademark of maxim integrated products. package information (continued) soicn.eps downloaded from: http:///
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