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1 ? fn7348.1 EL8302 500mhz rail-to-rail amplifier the EL8302 represents a triple rail-to-rail amplifier with a -3db bandwidth of 500mhz and slew rate of 600v/s. running off a very low supply current of 5.6ma per channel, the EL8302 also f eatures inputs that go to 0.15v below the v s - rail. the EL8302 includes a fast-acting disable/power-down circuit. with a 25ns disable and a 200ns enable, the EL8302 is ideal for multiplexing applications. the EL8302 is designed for a number of general purpose video, communication, instrumentation, and industrial applications. the EL8302 is available in an 16-pin so and 16-pin qsop packages and is sp ecified for operation over the -40c to +85c temperature range. pinout EL8302 (16-pin so, qsop) top view features ? 500mhz -3db bandwidth ? 600v/s slew rate ? low supply current = 5.6ma per amplifier ? supplies from 3v to 5.5v ? rail-to-rail output ? input to 0.15v below v s - ? fast 25ns disable ?low cost applications ? video amplifiers ? portable/hand-held products ? communications devices ina+ cea vs- ceb inb+ nc cec inc+ ina- outa vs+ outb inb- nc outc inc- - + 1 2 3 4 16 15 14 13 5 6 7 12 11 10 8 9 - + - + ordering information part number package tape & reel pkg. dwg. # EL8302is 16-pin so - mdp0027 EL8302is-t7 16-pin so 7? mdp0027 EL8302is-t13 16-pin so 13? mdp0027 EL8302iu 16-pin qsop - mdp0040 EL8302iu-t7 16-pin qsop 7? mdp0040 EL8302iu-t13 16-pin qsop 13? mdp0040 data sheet november 20, 2003 caution: these devices are sensitive to electrosta tic discharge; follow proper ic handling procedures. 1-888-intersil or 321-724-7143 | intersil (and design) is a registered trademark of intersil americas inc. copyright ? intersil americas inc. 2003. all rights reserved. elantec is a registered trademark of elantec semiconductor, inc. all other trademarks mentioned are the property of their respective owners.
2 important note: all parameters having min/max specifications are guaranteed. typ values are for information purposes only. unles s otherwise noted, all tests are at the specified temperature and are pulsed tests, therefore: t j = t c = t a absolute m aximum ratings (t a = 25c) supply voltage from v s + to v s - . . . . . . . . . . . . . . . . . . . . . . . . . 5.5v input voltage . . . . . . . . . . . . . . . . . . . . . . . . v s + + 0.3v to v s - -0.3v differential input voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2v continuous output current . . . . . . . . . . . . . . . . . . . . . . . . . . . 40ma power dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . see curves storage temperature . . . . . . . . . . . . . . . . . . . . . . . .-65c to +125c ambient operating temperature . . . . . . . . . . . . . . . .-40c to +85c operating junction temperature . . . . . . . . . . . . . . . . . . . . . . +125c caution: stresses above those listed in ?absolute maximum ratings? may cause permanent damage to the device. this is a stress o nly rating and operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. electrical specifications v s + = 5v, v s - = gnd, t a = 25c, v cm = 2.5v, r l to 2.5v, a v = 1, unless otherwise specified parameter description conditions min typ max unit input characteristics v os offset voltage -7 -0.8 +7 mv tcv os offset voltage temperature coefficient measured from t min to t max 3v/c ib input bias current v in = 0v -10 -6 a i os input offset current v in = 0v 0.1 0.6 a tci os input bias current temperature coefficient measured from t min to t max 2na/c cmrr common mode rejection ratio v cm = -0.15v to +3.5v 70 95 db cmir common mode input range v s - -0.15 v s + - 1.5 v r in input resistance common mode 7 m ? c in input capacitance 0.5 pf avol open loop gain v out = +1.5v to +3.5v, r l = 1k ? to gnd 75 100 db v out = +1.5v to +3.5v, r l = 150 ? to gnd 80 db output characteristics r out output resistance a v = +1 30 m ? v op positive output voltage swing r l = 1k ? 4.85 4.9 v r l = 150 ? 4.65 4.7 v v on negative output voltage swing r l = 150 ? 150 200 mv r l = 1k ? 50 70 mv i out linear output current 65 ma i sc (source) short circuit current r l = 10 ? 50 80 ma i sc (sink) short circuit current r l = 10 ? 90 150 ma power supply psrr power supply rejection ratio v s + = 4.5v to 5.5v 70 95 db i s-on supply current - enabled per amplifier 5.6 6.2 ma i s-off supply current - disabled per amplifier 40 90 a enable t en enable time 200 ns t ds disable time 25 ns v ih-enb enable pin voltage for power-up 0.8 v v il-enb enable pin voltage for shut-down 2 v EL8302
3 i ih-enb enable pin input current high 8.6 a i il-enb enable pin input for current low 0.01 a ac performance bw -3db bandwidth a v = +1, r f = 0 ? , c l = 1.5pf 500 mhz a v = -1, r f = 1k ? , c l = 1.5pf 140 mhz a v = +2, r f = 1k ? , c l = 1.5pf 165 mhz a v = +10, r f = 1k ? , c l = 1.5pf 18 mhz bw 0.1db bandwidth a v = +1, r f = 0 ? , c l = 1.5pf 36 mhz peak peaking a v = +1, r l = 1k ? , c l = 1.5pf 1 db gbwp gain bandwidth product 200 mhz pm phase margin r l = 1k ? , c l = 1.5pf 55 sr slew rate a v = 2, r l = 100 ? , v out = 0.5v to 4.5v 500 600 v/s t r rise time 2.5v step , 20% - 80% 4 ns t f fall time 2.5v step , 20% - 80% 2 ns os overshoot 200mv step 10 % t pd propagation delay 200mv step 1 ns t s 0.1% settling time 200mv step 15 ns dg differential gain a v = +2, r f = 1k ? , r l = 150 ? 0.01 % dp differential phase a v = +2, r f = 1k ? , r l = 150 ? 0.01 e n input noise voltage f = 10khz 12 nv/ hz i n + positive input noise current f = 10khz 1.7 pa/ hz i n - negative input noise current f = 10khz 1.3 pa/ hz e s channel separation f = 100khz 95 db electrical specifications v s + = 5v, v s - = gnd, t a = 25c, v cm = 2.5v, r l to 2.5v, a v = 1, unless otherwise specified parameter description conditions min typ max unit pin descriptions pin name function 1, 5, 8 ina+, inb+, inc+ non-inverting input for each channel 2, 4, 7 cea , ceb , cec enable and disable input for each channel 3 vs- negative power supply 6, 11 nc not connected 9, 12, 16 inc-, inb-, ina- inverting input for each channel 10, 13, 15 outc, outb, outa amplifier output for each channel 14 vs+ positive power supply EL8302
4 typical performance curves figure 1. frequency respo nse for various output voltage levels figure 2. small signal frequency response vs r f and r g figure 3. small signal frequency response for various non-inverting gains figure 4. small signal frequency response for various inverting gains figure 5. small signal frequency response for various r load figure 6. small signal frequency response vs various r load 5 3 1 -1 -3 -5 1m 10m 100m 1g frequency (hz) gain (db) v s =5v a v =1 r l =1k ? c l =1.5pf v op-p =200mv v op-p =2v v op-p =1v 4 2 0 -2 -4 5 3 1 -1 -3 -5 100k 1m 10m 100m 1g frequency (hz) normalized gain (db) v s =5v a v =2 r l =1k ? c l =1.5pf r f =r g =2k ? r f =r g =500 ? r f =r g =1k ? 5 3 1 -1 -3 -5 1m 10m 100m 1g frequency (hz) normalized gain (db) a v =1 v s =5v c l =1.5pf r l =1k ? a v =10 a v =5 a v =2 4 2 0 -2 -4 4 2 0 -2 -4 -6 100k 1m 10m 100m 1g frequency (hz) normalized gain (db) a v =-10 v s =5v c l =1.5pf r l =1k ? r f =1k ? a v =-1 a v =-5 5 3 1 -1 -3 -5 1m 10m 100m 1g frequency (hz) gain (db) v s =5v a v =1 c l =1.5pf v op-p =200mv 4 2 0 -2 -4 r l =100 ? r l =500 ? r l =1k ? 11 9 7 5 3 1 100k 1m 10m 100m 1g frequency (hz) gain (db) v s =5v a v =2 c l =1.5pf r f =r g =1k ? r l =500 ? r l =1k ? , 150 ? EL8302
5 figure 7. small signal frequency response vs c l figure 8. small signal frequency response for various c l figure 9. open loop gain and phase vs frequency figure 10. disabled output isolation frequency response figure 11. power supply rejection ratio vs frequency figure 12. small signal bandwidth vs supply voltage typical performance curves (continued) 5 3 1 -1 -3 -5 1m 10m 100m 1g frequency (hz) gain (db) c l =4.8pf c l =1.5pf v s =5v a v =1 r l =1k ? v op-p =200mv 4 2 0 -2 -4 c l =3.7pf 16 12 8 4 0 -4 1m 10m 100m 1g frequency (hz) gain (db) v s =5v a v =2 r l =1k ? r f =r g =1k ? c l =28.5pf c l =1.5pf c l =20pf c l =13.5pf c l =10pf 10 2 -2 6 14 110 70 30 -10 -50 -90 1k 10k 1m 100m 1g frequency (hz) gain (db) r l =1k ? phase () -45 405 315 225 135 45 100k 10m r l =150 ? r l =150 ? r l =1k ? -10 -30 -50 -70 -90 -110 1k 10k 100k 100m 1g frequency (hz) gain (db) v s =5v a v =1 r l =1k ? 1m 10m -10 -30 -50 -70 -90 -110 1k 10k 10m 100m frequency (hz) psrr (db) 100k 1m psrr- psrr+ 550 400 350 500 200 150 3 3.5 4.5 5 5.5 v s (v) bandwidth (mhz) r l =1k ? c l =1.5pf a v =1 a v =2 450 300 250 4 100 EL8302
6 figure 13. ouput impedance vs frequency figure 14. small signal peaking vs supply voltage figure 15. common-mode rejection ratio vs frequency figure 16. supply current vs supply voltage (per amplifier) figure 17. harmonic distortion vs output voltage figure 18. harmonic distortion vs load resistance typical performance curves (continued) 100 10 1 0.1 0.01 10k 100k 1m 10m frequency (hz) impedance ( ? ) 100m 2.5 1.5 0.5 0 3 3.5 4.5 5 5.5 v s (v) peaking (db) r l =1k ? c l =1.5pf a v =1 a v =2 2 1 4 -15 -35 -55 -75 -95 -115 100k 1m 10m 100m frequency (hz) cmrr (db) 10 4 8 0 01 34 5.5 v s (v) i s (ma) 6 2 2 0.5 1.5 3.5 4.5 5 2.5 -60 -70 -80 -100 15 v op-p (v) distortion (dbc) v s =5v r l =1k ? c l =1.5p f -90 34 2 h d 2 @ 1 0 m h z h d 2 @ 5 m h z h d 2 @ 1 m h z h d 3 @ 1 0 m h z h d 3 @ 5 m h z hd3@1mhz v s =5v r l =1k ? c l =1.5pf a v =2 -70 -75 -90 -100 100 2k r load ( ? ) distortion (dbc) -95 1k v o =1v p-p for a v =1 v o =2v p-p for a v =2 -85 -80 h d 2 @ a v = 2 h d 2 @ a v = 1 h d 3 @ a v = 2 h d 3 @ a v = 1 v s =5v f=5mhz EL8302
7 figure 19. harmonic distortion vs frequency figure 20. voltage and current noise vs frequency figure 21. channel separation vs frequency figure 22. large signal transient response - rising figure 23. large signal transient response - falling figure 24. small signal transient reponse typical performance curves (continued) -50 -70 -90 -60 -100 140 frequency (mhz) distortion (dbc) v s =5v r l =1k ? c l =1.5pf v o =1v p-p for a v =1 v o =2v p-p for a v =2 10 h d 2 @a v = 2 -80 h d 2 @ a v = 1 h d 3 @ a v = 2 h d 3 @ a v = 1 1k 100 1 10 100 10k 100k 10m frequency (hz) voltage noise (nv/ hz) current noise (pa/ hz), e n 10 1k 1m i n + i n - 0 -20 -40 -60 -80 -100 1.00e+05 1.00e+06 1.00e+07 1.00e+08 1.00e+09 frequency (hz) channel separation (db) ch2-->ch3 -10 -30 -50 -70 -90 ch2-->ch1 ch2-->ch1 ch3-->ch2 ch1-->ch2 ch1<=>ch3 2ns/div 1.5 2.5 3.5 v s =5v, a v =1, r l =1k ? to 2.5v, c l =1.5pf 2ns/div 1.5 2.5 3.5 v s =5v, a v =1, r l =1k ? to 2.5v, c l =1.5pf v s =5v, a v =1, r l =1k ? to 2.5v, c l = 1.5pf 10ns/div 2.4 2.6 2.5 2.6 2.4 2.5 v out v in EL8302
8 figure 25. output swing figure 26. output swing figure 27. enabled responses figure 28. disabled response figure 29. package power dissipation vs ambient temperature figure 30. package power dissipation vs ambient temperature typical performance curves (continued) v s =5v, a v =5, r l =1k ? to 2.5v 2s/div 0 2.5 5 v s =5v, a v =5, r l =1k ? to 2.5v 2s/div 0 2.5 5 ch1, ch2, 1v/div, m=100ns ch2 ch1 enable input v out ch1, ch2, 0.5v/div, m=20ns ch2 ch1 enable input v out 633mw j a = 1 5 8 c / w q s o p 1 6 1.2 1 0.8 0.6 0.4 0 0 255075100 150 ambient temperature (c) power dissipation (w) 125 85 jedec jesd51-3 low effective thermal conductivity test board 0.2 j a = 1 1 0 c / w s o 1 6 ( 0 . 1 5 0 ? ) 909mw 893mw j a = 1 1 2 c / w q s o p 1 6 1.4 1.2 1 0.8 0.6 0.2 0 0 255075100 150 ambient temperature (c) power dissipation (w) 125 85 jedec jesd51-7 high effective thermal conductivity test board 0.4 1.250w j a = 8 0 c / w s o 1 6 ( 0 . 1 5 0 ? ) EL8302
9 simplified schematic diagram description of operat ion and application information product description the EL8302 is wide bandwidth, single supply, low power and rail-to-rail output voltage f eedback operational amplifiers. the amplifiers are internally compensated for closed loop gain of +1 of greater. connected in voltage follower mode and driving a 1k ? load, the EL8302 has a -3db bandwidth of 500mhz. driving a 150 ? load, the bandwidth is about 350mhz while maintaining a 600v/us slew rate. the EL8302 is available with a power down pin for each channel to reduce power to 30a typically while the amplifier is disabled. input, output and supply voltage range the EL8302 has been designed to operate with a single supply voltage from 3v to 5.0v. split supplies can also be used as long as their total voltage is within 3v to 5.0v. the amplifiers have an input common mode voltage range from 0.15v below the negative supply (v s - pin) to within 1.5v of the positive supply (v s + pin). if the input signal is outside the above specified range, it will cause the output signal to be distorted. the output of the EL8302 can swin g rail to rail. as the load resistance becomes lower, the ability to drive close to each rail is reduced. for the load resistor 1k ? , the output swing is about 4.9v at a 5v supply. for the load resistor 150 ? , the output swing is about 4.6v. choice of feedback resistor and gain bandwidth product for applications that require a gain of +1, no feedback resistor is required. just shor t the output pin to the inverting input pin. for gains greater than +1, the feedback resistor forms a pole with the parasitic capacitance at the inverting input. as this pole becomes smaller, the amplifier?s phase margin is reduced. this causes ringing in the time domain and peaking in the frequency domain. therefore, r f has some maximum value that should not be exceeded for optimum performance. if a large value of r f must be used, a small capacitor in the few pf range in parallel with r f can help to reduce the ringing and peaking at the expense of reducing the bandwidth. as far as the output stage of t he amplifier is concerned, the output stage is also a gain stage with the load. r f and r g appear in parallel with r l for gains other th an +1. as this combination gets smaller, the bandwidth falls off. consequently, r f also has a minimum value that should not be exceeded for optimum performance. for gain of +1, r f =0 is optimum. for the gains other than +1, optimum response is obtained with r f between 300 ? to 1k ? . the EL8302 has a gain bandwidth product of 200mhz. for gains 5, its bandwidth can be predicted by the following equation: video performance for good video performance, an amplifier is required to maintain the same output impedance and the same frequency response as dc levels are changed at the output. this is especially difficult when driving a standard video load of 150 ? , because the change in output current with dc level. special circuitry has been incorporated in the EL8302 to reduce the variation of the output impedance with the current output. this results in dg and dp specifications of 0.01% and 0.01 , while driving 150 ? at a gain of 2. driving high impedance loads would give a similar or better dg and dp performance. in+ in- i 1 i 2 r 6 r 3 r 1 r 2 q 1 q 2 r 7 v bias1 q 5 q 6 r 8 q 7 q 8 r 9 q 3 q 4 r 4 r 5 v s- out v bias2 v s+ differential to drive generator single ended gain bw 200mhz = EL8302
10 driving capacitive loads and cables the EL8302 can drive 5pf loads in parallel with 1k ? with less than 5db of peaking at gain of +1. if less peaking is desired in applications, a small series resistor (usually between 5 ? to 50 ? ) can be placed in series with the output to eliminate most peaking. however, this will reduce the gain slightly. if the gain setting is greater than 1, the gain resistor r g can then be chosen to make up for any gain loss which may be created by the additional series resistor at the output. when used as a cable driver, double termination is always recommended for reflection-free performance. for those applications, a back-termination series resistor at the amplifier?s output will isolate th e amplifier from the cable and allow extensive capacitive drive. however, other applications may have high capacitive loads without a back-termination resistor. again, a small series resistor at the output can help to reduce peaking. disable/power-down the EL8302 can be disabled and placed its output in a high impedance state. the turn off time is about 25ns and the turn on time is about 200ns. when disabled, the amplifier?s supply current is reduced to 30a typically, thereby effectively eliminating the power consumption. the amplifier?s power down can be controlled by standard ttl or cmos signal levels at the enable pin. the applied logic signal is relative to v s - pin. letting the enable pin float or applying a signal that is less than 0.8v above v s - will enable the amplifier. the amplifier will be disabled when the signal at enable pin is 2v above v s -. output drive capability the EL8302 does not have inter nal short circuit protection circuitry. they have a typical short circuit current of 80ma sourcing and 150ma sinking for the output is connected to half way between the rails with a 10 ? resistor. if the output is shorted indefinitely, the power dissipation could easily increase such that the part will be destroyed. maximum reliability is maintained if the output current never exceeds 40ma. this limit is set by the design of the internal metal interconnections. power dissipation with the high output drive capa bility of the EL8302, it is possible to exceed the 125 c absolute maximum junction temperature under certain load current conditions. therefore, it is important to calculate the maximum junction temperature for the application to determine if the load conditions or package types need to be modified for the amplifier to remain in the safe operating area. the maximum power dissipation allowed in a package is determined according to: where: t jmax = maximum junction temperature t amax = maximum ambient temperature ja = thermal resistance of the package the maximum power dissipation actually produced by an ic is the total quiescent supply current times the total power supply voltage, plus the power in the ic due to the load, or: for sourcing: for sinking: where: v s = total supply voltage i smax = maximum quiescent supply current v outi = maximum output voltage of the application for each channel r loadi = load resistance tied to ground for each channel i loadi = load current for eachh channel by setting the two pd max equations equal to each other, we can solve the output current and r load to avoid the device overheat. power supply bypassing and printed circuit board layout as with any high frequency device, a good printed circuit board layout is necessary for optimum performance. lead lengths should be as short as possible. the power supply pin must be well bypassed to reduce the risk of oscillation. for normal single supply operation, where the v s - pin is connected to the ground plane, a single 4.7f tantalum capacitor in parallel with a 0. 1f ceramic capacitor from v s + to gnd will suffice. this same capacitor combination should be placed at each supply pin to ground if split supplies are to be used. in this case, the v s - pin becomes the negative supply rail. for good ac performance, parasitic capacitance should be kept to a minimum. use of wire wound resistors should be pd max t jmax t amax ? ja -------------------------------------------- - = pd max v s i smax v s v outi ? () v outi r li ----------------- i1 = 3 + = pd max v s i smax v outi v s - ? () i loadi i1 = 3 + = EL8302
11 avoided because of their additional series inductance. use of sockets should also be avoided if possible. sockets add parasitic inductance and capacitance that can result in compromised performanc e. minimizing parasitic capacitance at the amplifier?s inverting input pin is very important. the feedback resistor should be placed very close to the inverting input pin. strip line design techniques are recommended for the signal traces. typical applications video sync pulse remover many cmos analog to digital converters have a parasitic latch up problem when subjected to negative input voltage levels. since the sync tip contains no useful video information and it is a negativ e going pulse, we can chop it off. figure 31 shows a gain of 2 connections for EL8302. figure 32 shows the complete input video signal applied at the input, as well as the outp ut signal with the negative going sync pulse removed. multiplexer besides the normal power down usage, the enable pin of the EL8302 can be used for multiplexing applications. figure 33 shows two channels with the outputs tied together, driving a back terminated 75 ? video load. a 2v p-p 2mhz sine wave is applied to amp a and a 1v p-p 2mhz sine wave is applied to amp b. figure 34 shows the enable signal and the resulting output waveform at v out . observe the break- before-make operation of the multiplexing. amp a is on and v in1 is passed through to the output when the enable signal is low and turns off in about 25ns when the enable signal is high. about 200ns later, amp b turns on and v in2 is passed through to the output. the break-before-make operation ensures that more than one amplifier isn?t trying to drive the bus at the same time. single supply video line driver the EL8302 is wideband rail-to-rail output op amplifiers with large output current, excellent dg, dp, and low distortion that allow them to drive video signals in low supply applications. figure 35 is the single supply non-inverting video line driver configuration and figure 36 is the inverting video ling driver configuration. the signal is ac coupled by c 1 . r 1 and r 2 are used to level shift the in put and output to provide the largest output swing. r f and r g set the ac gain. c 2 isolates the virtual ground potential. r t and r 3 are the termination resistors for the line. c 1 , c 2 and c 3 are selected big enough to minimize the droop of the luminance signal. figure 31. sync pulse remover 5v 1k v out v in 75 ? + - 75 ? 1k 75 ? v s+ v s- figure 32. video signal 1v 0.5v 0v 1v 0.5v 0v m = 10s/div v out v in figure 33. two to one multiplexer +2.5v 1k 2mhz 75 ? + - 1k 75 ? -2.5v v out 75 ? 1v p-p b +2.5v 1k 2mhz + - 1k 75 ? -2.5v 2v p-p a enable figure 34. 0v -0.5v -1.5v -2.5v 1v 0v m = 50ns/div a enable b -1v EL8302
12 figure 35. 5v single supply non inverting video line driver figure 36. single supply inverting video line driver figure 37. video line driver frequency response 5v r f v out v in 75 ? + - 75 ? 1k ? 75 ? c 3 470f r 3 c 1 47f r t 10k 10k r 2 r 1 1k ? r g c 2 220f 5v r f v out v in 75 ? - + 75 ? 500 ? 75 ? c 3 470f r 3 c 1 47f r t 10k 10k r 2 r 1 1k ? r g c 2 220f 5v 4 3 2 1 0 -1 -2 -3 -4 -5 normalized gain (db) 100k 1m 10m 100m 500m frequency (hz) a v = -2 a v = 2 -6 EL8302
13 so package outline drawing EL8302
14 all intersil u.s. products are manufactured, asse mbled and tested utilizing iso9000 quality systems. intersil corporation?s quality certifications ca n be viewed at www.intersil.com/design/quality intersil products are sold by description only. intersil corpor ation reserves the right to make changes in circuit design, soft ware and/or specifications at any time without notice. accordingly, the reader is cautioned to verify that data sheets are current before placing orders. information furnishe d by intersil is believed to be accurate and reliable. however, no responsibility is assumed by intersil or its subsidiaries for its use; nor for any infringements of paten ts or other rights of third parties which may result from its use. no license is granted by implication or otherwise under any patent or patent rights of intersil or its subsidiari es. for information regarding intersil corporation and its products, see www.intersil.com qsop package outline drawing note: the package drawing shown here may not be the latest version. to check the latest revision, please refer to the intersil w ebsite at http://www.intersil.com/design/packages/index.asp EL8302

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