_______________________________________________________________ maxim integrated products 1 for pricing, delivery, and ordering information, please contact maxim direct at 1-888-629-4642, or visit maxims website at www.maxim-ic.com. MAX14979E high-bandwidth, 15kv esd protection lvds switch 19-5252; rev 0; 4/10 typical operating circuit appears at end of data sheet. general description the MAX14979E is optimized for high-speed differential switching applications. the device is ideal for low-volt - age differential signal (lvds) and low-voltage positive emitter-coupled logic (lvpecl) switching applications. the MAX14979E provides enhanced electrostatic dis - charge (esd) protection up to q 15kv and excellent high- frequency response, making this device especially use - ful for interfaces that must go to an outside connection. the MAX14979E provides extremely low capacitance (c on ) as well as low resistance (r on ) for low-insertion loss and bandwidth up to 650mhz (1.3gbps). in addi - tion to the four pairs of double-pole/double-throw (dpdt) switches, the MAX14979E provides low-frequency (up to 50mhz) and aux switching that can be used for led lighting or other applications. the MAX14979E is available in a space-saving 36-pin tqfn package and operates over the standard -40 n c to +85 n c temperature range. applications notebook computers switch lvds to graphics panels lvds and lvpecl switching ordering information features s 15kv esd protected per mil-std-883, method 3015 s single +3.0v to +3.6v power-supply voltage s low on-resistance (r on ): 4 i (typ), 6.5 i (max) s low on-capacitance (c on ): 8pf (typ) s -23db return loss (100mhz) s -3db bandwidth: 650mhz s built-in aux switches for switching indicators s low 450a (max) quiescent current s bidirectional 8 to 16 multiplexer/demultiplexer s space-saving, lead-free, 36-pin, 6mm x 6mm tqfn package eye diagram + denotes a lead(pb)-free/rohs-compliant package. * ep = exposed pad. 500ps/div 100mv/div f = 300mhz part temp range pin-package MAX14979Eetx+ -40 n c to +85 n c 36 tqfn-ep*
MAX14979E high-bandwidth, 15kv esd protection lvds switch 2 stresses beyond those listed under absolute 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. (voltages referenced to gnd.) v+ ......................................................................... -0.3v to +4.0v all other pins ............................................... -0.3v to (v+ + 0.3v) continuous current (com_ _ to nc_ _/no_ _) ............ q 120ma continuous current (aux0_ to aux1_/aux2_) ............... q 40ma peak current (com_ _ to nc_ _/no_ _) (pulsed at 1ms, 10% duty cycle) ............................... q 240ma current into any other pin .............................................. q 20ma continuous power dissipation (t a = +70 n c) 36-pin tqfn (derate 35.7mw/ n c above +70 n c) ....... 2.85mw esd protection, human body model (hbm) .................... q 15kv junction-to-ambient thermal resistance b ja (note 1) ................................................................... 8 n c/w junction-to-case thermal resistance b jc (note 1) ................................................................... 1 n c/w operating temperature range ........................ -40 n c to +85 n c junction temperature .................................................. +150 n c storage temperature range ......................... -65 n c to +150 n c lead temperature (soldering 10s) ................................ +300 n c soldering temperature (reflow) ...................................... +260 n c electrical characteristics (v+ = +3.0v to +3.6v, t a = t j = t min to t max , unless otherwise noted. typical values are at v+ = +3.3v, t a = +25 n c.) (note 2) absolute maximum ratings note 1: package thermal resistances were obtained using the method described in jedec specification jesd51-7, using a four- layer board. for detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial . parameter symbol conditions min typ max units power supplies operating power-supply range v cc +3.0 +3.6 v analog switch on-resistance r on v+ = 3v, i com_ _ = -40ma, v com_ _ = 0v, 1.5v, 3v t a = +25 n c 4 5.5 i t min to t max 6.5 on-resistance aux switches r onaux v+ = 3v, i aux0_ = -40ma, v aux0_ = 0v, 1.5v, 3v 40 i on-resistance match between channels d r on v+ = 3v, i com_ _ = -40ma, v com_ _ = 0v, 3v (note 3) t a = +25 n c 0.5 1.5 i t min to t max 2 on-resistance flatness r flat(on) v+ = 3v, i com_ _ = -40ma, v com_ _ = 0v, 1.5v 0.01 i off-leakage current i lcom_ _(off) v+ = 3.6v, v com_ _ = 0.3v, 3.3v; v nc_ _ or v no_ _ = 3.3v, 0.3v -1 +1 f a on-leakage current i lcom_ _(on) v+ = 3.6v, v com_ _ = 0.3v, 3.3v; v nc_ _ or v no_ _ = 3.3v, 0.3v or unconnected -1 +1 f a switch ac performance insertion loss i los r s = r l = 50 i , unbalanced, f = 1mhz, (note 3) 0.6 db return loss r los f = 100mhz -23 db crosstalk v ct1 any switch to any switch; r s = r l = 50 i , unbalanced, figure 1 f = 25mhz -50 db v ct2 f = 125mhz -26 switch ac characteristics -3db bandwidth bw r s = r l = 50 i , unbalanced 650 mhz off-capacitance c off f = 1mhz, com_ _ 3.5 pf on-capacitance c on f = 1mhz, com_ _ 8 pf
MAX14979E high-bandwidth, 15kv esd protection lvds switch 3 electrical characteristics (continued) (v+ = +3.0v to +3.6v, t a = t j = t min to t max , unless otherwise noted. typical values are at v+ = +3.3v, t a = +25 n c.) (note 2) note 2: specifications at t a = -40 n c are guaranteed by design. note 3: guaranteed by design. figure 1. single-ended bandwidth, crosstalk, and off-isolation r15 49.9? network analyzer network analyzer network analyzer network analyzer single-ended bandwidth 50? trace single-ended crosstalk 50? trace single-ended off-isolation 50? trace 50? trace com0+ 36 com1+ 2 com1- 3 com2+ 7 nc2+ 22 nc1- 25 nc1+ 26 nc0+ 31 50? trace network analyzer network analyzer 50? trace r14 49.9? r13 49.9? MAX14979E parameter symbol conditions min typ max units turn-on time t on v com_ _ = 1v, r l = 100 i , figure 2 50 ns turn-off time t off v com_ _ = 1v, r l = 100 i , figure 2 50 ns propagation delay t plh , t phl r s = r l = 50 i , unbalanced, figure 3 0.1 ns output skew between ports t sk(o) skew between any two ports, figure 4 0.01 ns switch logic input-voltage low v il v+ = 3.0v 0.8 v input-voltage high v ih v+ = 3.6v 2.0 v input-logic hysteresis v hyst v+ = 3.3v 100 mv input leakage current i sel v+ = 3.6v, v sel = 0v or v+ -5 +5 f a quiescent supply current i+ v+ = 3.6v, v sel = 0v or v+ 280 450 f a esd protection esd protection com_ _, nc_ _, no_ _ hbm (spec mil-std-883, method 3015) q 15 kv all other pins hbm (spec mil-std-883, method 3015) q 2 kv
MAX14979E high-bandwidth, 15kv esd protection lvds switch 4 figure 2. turn-on and turn-off times figure 3. propagation delay times figure 4. output skew sel 50% 50% t off 50% 50% 50% 50% v ih v il 0v 0v nc_ _ no_ _ t on t off t on com_ _ nc_ _ no_ _ v h 2.0v 2.0v 1.0v 3.0v v l t plh t phl the MAX14979E switches are fully bidirectional. pulse skew = t sk(o) = |t phl - t plh | 2.0v 3.0v 1.0v the MAX14979E switches are fully bidirectional. v oh v ol 2.0v com_ _ nc_ _ no_ _ nc_ _ no_ _ output skew = t sk = |t plh - t plh | or |t phl - t phl | v oh v ol 2.0v t plh t phl t plh t phl
MAX14979E high-bandwidth, 15kv esd protection lvds switch 5 typical operating characteristics (v+ = 3.3v, t a = +25 n c, unless otherwise noted.) single-ended insertion loss vs. frequency MAX14979E toc05 frequency (mhz) insertion loss (db) 100 10 -7 -6 -5 -4 -3 -2 -1 0 -8 1 1000 200 220 240 260 280 300 320 340 -40 -15 10 35 60 85 quiescent supply current vs. temperature MAX14979E toc04 temperature (c) quiescent supply current (a) v+ = 3.6v 0 12 8 4 16 20 24 28 32 36 40 -40 10 -15 35 60 85 leakage current vs. temperature MAX14979E toc03 temperature (c) leakage current (pa) i l (on) i l (off) 0 8 10 12 14 6 2 4 16 18 22 20 24 0 1.0 0.5 1.5 2.0 2.5 3.0 aux_ on-resistance vs. v aux_ MAX14979E toc02 v aux_ (v) r onled (?) t a = +85c t a = +25c t a = -40c 0 2 1 4 3 5 6 0 1.0 1.5 0.5 2.0 2.5 3.0 on-resistance vs. v com_ _ MAX14979E toc01 v com_ _ (v) r on ( ? ) t a = +85c t a = +25c t a = -40c
MAX14979E high-bandwidth, 15kv esd protection lvds switch 6 pin configuration pin description sel nc1+ no1+ no1- no2+ no2- nc2+ nc2- nc1- com1- aux0a aux1b com2+ com2- com3+ com0- 1 2 3 4 5 6 7 8 9 18 17 16 15 14 13 12 11 10 28 29 30 31 32 33 34 35 36 27 26 25 24 23 22 21 20 19 aux2a aux1a aux0b com3- no3- no3+ nc3- nc3+ no0+ nc0- nc0+ aux2 aux1 aux0 + v+ com0+ ep no0- tqfn (6mm 6mm) top view aux2b gnd com1+ MAX14979E pin name function 1 com0- common lvds differential terminal for switch 0 2 com1+ common lvds differential terminal for switch 1 3 com1- common lvds differential terminal for switch 1 4 aux0a aux0a input 5 aux1b aux1b output. drive sel low (sel = 0) to connect aux0a to aux1b. 6 aux2b aux2b output. drive sel high (sel = 1) to connect aux0a to aux2b. 7 com2+ common lvds differential terminal for switch 2 8 com2- common lvds differential terminal for switch 2 9 com3+ common lvds differential terminal for switch 3 10 com3- common lvds differential terminal for switch 3 11 gnd ground 12 aux0b aux0b input 13 aux1a aux1a output. drive sel low (sel = 0) to connect aux0b to aux1a. 14 aux2a aux2a output. drive sel high (sel = 1) to connect aux0b to aux2a. 15 no3- normally open lvds differential terminal for switch 3 16 no3+ normally open lvds differential terminal for switch 3 17 nc3- normally closed lvds differential terminal for switch 3 18 nc3+ normally closed lvds differential terminal for switch 3 19 no2- normally open lvds differential terminal for switch 2 20 no2+ normally open lvds differential terminal for switch 2 21 nc2- normally closed lvds differential terminal for switch 2
MAX14979E high-bandwidth, 15kv esd protection lvds switch 7 detailed description the MAX14979E is a high-speed analog switch targeted at lvds and other low-voltage switching up to 600mhz. in a typical application, the MAX14979E switches two sets of lvds sources to a laptop lvds panel. for extra security, the MAX14979E is protected against q 15kv esd shocks. see the functional diagram. with its low resistance and capacitance, as well as high- esd protection, the MAX14979E can be used to switch most low-voltage differential signals, such as lvds and lvpecl, as long as the signals do not exceed the maxi - mum ratings of the device. the MAX14979E switches provide low capacitance and on-resistance to meet low insertion loss and return-loss specifications. the MAX14979E has three additional aux switches. digital control inputs the MAX14979E provides a single digital control sel. sel controls the switches as well as the aux switches, as shown in table 1. analog-signal levels the on-resistance of the MAX14979E is very low and stable as the analog input signals are swept from ground to v+ (see the typical operating characteristics ). the switches are bidirectional, allowing com_ _ and nc_ _/ no_ _ to be configured as either inputs or outputs. esd protection the MAX14979E is characterized using the hbm for q 15kv of esd protection. figure 5 shows the hbm. this model consists of a 100pf capacitor charged to the esd voltage of interest, which is then discharged into the test device through a 1.5k i resistor. all signal and control pins are esd protected to q 15kv hbm. pin description (continued) figure 5. human body esd test model (mil-std-883, method 3015) charge-current limit resistor discharge resistance storage capacitor c s 100pf r c 1m? r d 1500? high- voltage dc source device under test pin name function 22 nc2+ normally closed lvds differential terminal for switch 2 23 no1- normally open lvds differential terminal for switch 1 24 no1+ normally open lvds differential terminal for switch 1 25 nc1- normally closed lvds differential terminal for switch 1 26 nc1+ normally closed lvds differential terminal for switch 1 27 sel select input. sel selects switch connection. see table1. 28 no0- normally open lvds differential terminal for switch 0 29 no0+ normally open lvds differential terminal for switch 0 30 nc0- normally closed lvds differential terminal for switch 0 31 nc0+ normally closed lvds differential terminal for switch 0 32 aux2 aux2 output. drive sel high (sel = 1) to connect aux0 to aux2. 33 aux1 aux1 output. drive sel low (sel = 0) to connect aux0 to aux1. 34 aux0 aux0 input 35 v+ positive-supply voltage input. bypass v+ to gnd with a 0.1 f f ceramic capacitor. 36 com0+ common lvds differential terminal for switch 0 ep exposed pad. connect exposed pad to gnd or leave it unconnected.
MAX14979E high-bandwidth, 15kv esd protection lvds switch 8 applications information typical operating circuit the typical operating circuit shows the MAX14979E in a dual graphics application. power-supply sequencing and overvoltage protection caution: do not exceed the absolute maximum ratings. stresses beyond the listed ratings may cause permanent damage to the device. proper power-supply sequencing is recommended for all cmos devices. always apply v+ before applying analog signals, especially if the analog signal is not cur - rent limited. layout high-speed switches require proper layout and design procedures for optimum performance. keep design- controlled-impedance pcb traces as short as possible. ensure that bypass capacitors are as close as possible to the device. use large ground planes where possible. chip information process: bicmos package information for the latest package outline information and land patterns, go to www.maxim-ic.com/packages . note that a +, #, or - in the package code indicates rohs status only. package drawings may show a different suffix character, but the drawing pertains to the package regardless of rohs status. functional diagram table 1. truth table MAX14979E nc0+ com0+ nc0- com0- no0- no0+ nc1+ com1+ nc1- com1- no1- no1+ nc2+ com2+ nc2- com2- no2- no2+ nc3+ com3+ nc3- com3- no3- no3+ aux1a aux0a aux2a aux1b aux1 aux0b aux2b aux0 sel aux2 sel connection 0 com_ _ to nc_ _, aux0_ to aux1_ 1 com_ _ to no_ _, aux0_ to aux2_ package type package code document no. 36 tqfn-ep t3666+3 21-0141
MAX14979E high-bandwidth, 15kv esd protection lvds switch 9 typical operating circuit MAX14979E com0+ com0- com1+ com1- com2+ com2- sel control no0+ no0- no1+ no1- no2+ no2- no3+ no3- com3+ com3- nc0+ nc0- nc1+ nc1- nc2+ nc2- nc3+ nc3- lvds_+ lvds_- clock_- clock_+ lvds_- lvds_+ lvds_- lvds_+ lvds_+ lvds_- clock_- clock_+ lvds_- lvds_+ lvds_- lvds_+ internal graphics lvds lcd panel MAX14979E com0+ com0- com1+ com1- com2+ com2- sel control no0+ no0- no1+ no1- no2+ no2- no3+ no3- com3+ com3- nc0+ nc0- nc1+ nc1- nc2+ nc2- nc3+ nc3- lvds_+ lvds_- clock_- clock_+ lvds_- lvds_+ lvds_- lvds_+ lvds_+ lvds_- clock_- clock_+ lvds_- lvds_+ lvds_- lvds_+ svdo to lvds note: the MAX14979E has three spdt auxilliary switches (aux) that can be used for other switching such as leds and i 2 c. these are not shown in the diagram.
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 ? 2010 maxim integrated products maxim is a registered trademark of maxim integrated products, inc. MAX14979E high-bandwidth, 15kv esd protection lvds switch revision history revision number revision date description pages changed 0 4/10 initial release
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