ANALOG DEVICES single Supply, Low Power, Triple Video Amplifier AD8013 FEATURES Three Video Amplifiers in One Package Drives Large Capacitive Load Excellent Video Specifications (R= 150 2) Gain Flatness 0.1 dB to 60 MHz 0.02% Differential Gain Error 0.06 Differential Phase Error Low Power Operates on Single +5 V to +13 V Power Supplies 4mA/Amplifier Max Power Supply Current High Speed 140 MHz Unity Gain Bandwidth (3 dB) Fast Settling Time of 18 ns (0.1%) 1000 V/s Slew Rate High Speed Disable Function per Channel Turn-Off Time 30 ns Easy to Use 95 mA Short Circuit Current Output Swing to Within 1 V of Rails APPLICATIONS LCD Displays Video Line Driver Broadcast and Professional Video Com puter Video Plug-In Boards Consumer Video RGB Amplifier in Component Systems PRODUCT DESCRIPTION The AD 8013 isa low power, sngk suppl, top video am plier. Each of the three am plifershas 30 mA ofoutput current, and is optim ized fordriving one back tem inated video bad (150 Q) each. Each am plifier is a current fedback am p- lifer and atures gain fatnessot0 1 dB to 60M AH zwhieoterng NORMALIZED GAIN dB 100M 1G FREQUENCY Hz 1M 10m Fine-Seale Gain Flatness vs. Frequency, G = +2, A, = 1500 REV. A Information furnished by Analog Devices is beliaved to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents 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 Analog Devices. PIN CONFIGURATION 14-Pin DIP & SOIC Package Se DISABLE 1 [| 14] our 2 DISABLE 2 [2 | As -IN2 DISABLE 3 [3 | [12] +1N 2 +Vs[4] apsoi3 []-v. 4in1 [5] [io] +IN3 N14 ay Wp-s out1 [7] [8] ours differential gain and phase erorof0.02% and 0.06. This makes the AD 8013 ideal for broadcast and pro fessional video electronics. TheAD 8013 offers low powerof4mA peram pliterm ax and munsonasnge+5V to+13V power supply. The outputsof each am plier sw ing to within one volt ofeither supply railto easily accom m odate video signals. The AD 8013 isunique am ong current tedback op am ps by virtue ofits large capacitive Jjoad drive. Each op am p is capabk ofdriymg large capacitive Joads white stillachieving rapid settling tm e. For mnstance can settle In 18 nsdriving a resistive load, and achieves 40 ns (0.1% ) settling whie driving 200 pF. The outstanding bandwidth of 140 M H z along with 1000 V fis of slew rate m ake the AD 8013 usetulm m any general purpose high speed app lcations where a smgle +5 V ordualpower supplies up to+6.5 V are required. Furthem ore the AD 8013's high speed disable function can be used te powerdown the am pliferorto put the outout nm a high m pedance state. This can then be used in video m ultiplexing applications. The AD 8013 is available in the Industmaltem perature range of -40C to +B5C . Channel Switching Characteristics for a 3:1 Mux Analog Devices, Inc., 1995 One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 617/329-4700 Fax: 617/ 326-8703AD801 3-SPEC A CAT ONS ec Ta= +25C, Rion = 150 , unless otherwise noted) M odel AD&8013A Conditions Vs Min Typ M ax Units DYNAM IC PERFORM ANCE Bandwidth (3 dB) No Peaking,G = +2 +5V 100 125 MHz No Peaking,G =+2 +5V 110 140 MHz Bandwidth (0.1 dB) No Peaking,G =+2 +5 V 50 MHz No Peaking,G =+2 +5V 60 MHz Siew Rate 2V Step +5V 400 V Als 6V Step +5V 600 1000 V fs Setting Tmeto 0.1% OVto+2Vv +5V 18 ns 45V Step,Croap = 200 pF +6V 40 ns Rioap > 1 4Q2,Reg = 442 NOGEHARMONIC PERFORM ANCE T otalH arm onic D distortion &=5MHz,R,=1k +5 VY -76 dBe =5MHz,R,= 1502 +5V -66 dBe Input Voltage N ose f= 10kHz +5V,45V 35 nv NHz Input C urentN ose f= 10 kHz (Ip) $5V,t5V 12 pA NHz D iffrentalG am @, = 150 Q) f=358MHz,6 =+2 +5y? 0.05 % +5V 0.02 0.05 % D iffrential Phase (RB, = 150 Q) f=358MH2z,G =+4+2 +5Vi 0.06 D egrees +5V 0.06 0.12 D egrees De PERFORM ANCE Thput fret Vo tage Taw tO Tuas +5V,t5V 2 5 mV O fiset D rit 7 wy PC Thput B jas C urrent -) +5V,25V 2 10 pA Tnput Bias Current ++) Tum to Tuax +5V,25V 3 15 PA pen-Leop T ransresistance +5V 650 goo kQ Tum to Tuax 550 kQ +5V go0k 11M Q Tum to Tuax 650 kO INPUT CHARACTERISTICS Input Resistance + Input t5V 200 k 2 Input r5V 150 Q Input apacitance +5V 2 pF Tnput C om m on-M ode Vo Itage R ange +5V 38 +tV +5V 12 38 +V Common-M ode Rection Ratio Input 0 fet Voltage +5V 52 56 dB Input fiset Voltage +5 V 52 56 aB -Tnput C urent +5V,05V 02 o4 HA A + Input C urment +5V,45V 5 7 HA AY OUTPUT CHARACTERISTICS Output Voltage Sw ng R,=1kQ Vot- re 08 10 Vv VooeVou 08 1.0 Vv R, = 1502 Vot-V ep ia 13 Vv VeoVou 11 13 Vv Output urrent +5 V 30 mA +5V 25 30 mA Shortt rut urent +5V 95 mA Capacitive Load D rive +5V 1000 pF MATCHING CHARACTERISTICS D ynam ic C vosstalk G=+2,f=5MHz +5V,t5V 70 dB Gam FlatnessM atch f= 20M Hz +5V O.1 dB DC Tnput. fet V o Itage +5V,t5V 0.3 mV Tnput Bias Current +5V,t5V me) pA REV. AAD8013 M odel AD8013A Conditions Vs Min Typ M ax Units POW ER SUPPLY peratng R ange Singk Supply +42 +13 Vv Dual Supply +2.1 +65 Vv @ Wescent C urrentAm plifier +5V 3.0 3.5 mA t5V 34 40 mA t65V 34 mA @ utescent C urrentAm plifier PowerD own +5 V 0.25 0.35 mA +5V 03 oA mA Power Supply Repction R ato Tnput. fiset V o Itage Ve =t25V wthVv 70 76 aB Input Curent +5V,t5V 0.03 02 HA AF + Input urnent +5V,4t5V 0.07 1.0 PA A DISABLE CHARACTERISTES fF Isolation f=6MHz +5V,t5V -70 cB 0 utput Im pedance G=+H1 +5V,t5V 12 pF TumoOonTme 50 ns TumofTme 30 ns Switchng Threshold -Vet xV 13 16 13 V NOTES 1T he test circuit for differentialgain and phase m easurem entsona+5V supply isac coupkd. Specifications sub pct to change without notice. ABSOLUTE MAXIMUM RATINGS! Supply Voltage 6... ee 13.2V Total Intemal? ow erD issipation? Plastic (N} 2... ee aee 1.6W atts bserve D erating Curves) SmallOutime )....1.0W atts Observe D eratng C urves) Input V cltage (CommonM ode) .. LoweroftV., ort1225V D iffrentialInputVoltage ........ Gutput +6V tC lam ped) Output Voltage Lim it Maxmum ...veaaee LowerotH12V from -Vs) or Vs) Minimum ......... H igherof (-12.5V trom +Vs5) or (V3) Output Short C ircuit D uration See Observe PowerD erating C urves Storage T em perature Range N andR Package .......-2. 000002 eee 65C to +125C O peratng Tem perature Range AD 8013A Lhe eee te eee -40C to + 85C Lead Tem perature Range (Solderng 10 sec) ........ +300C NOTES "Stresses above those listed under Absolute M axinum Ratings may cause pei anent damage to the device. This isa stess ratng only and fiinctional operation of the device at these or any other conditions above those Indicated in the operational section ofthis specification isnot im plied. Exposure to absolute Maximum Power Dissipation Them aximum powerthat can be sately dissipated by the AD 8013 is lim ited by the associated rise m junction tem perature. The maxinum sate nection tem perature forthe plastic encapsulated parts is detem ned by the glass Pansition tem perature ofthe plastic, about 150C . Exceeding this lim it tem porariy m ay cause a shitt In param etric pertorm ance due to a change in the stresses exerted on the die by the package. Exceeding a junction tem perature of 175C iran extended period can rwsulkn device faire. W hile the AD 8013 is mtemaly short ctrouit protected, thism ay netbe enough to quarantee thatthem axmum jnction tem per- ature isnot exceeded under allconditions. To ensure proper operation, ibis m portant to observe the derating curves. Ttm ust also be noted that in Mmoninvertng) gain con figurations with low valies of gain resistor), a high levelof input overdrive can result in a large Inputerror current, which m ay wsuk in a significant pow er dissipation in the Input stage. Thus power must be Inctided when com puttng the jinction tem perature nse due to total ntemal power. maxin um rating conditions forextended periodsm ay affect device mlability. 25 TTT *Specification is for device in fiee air: Q NJ Ty=+150C 144 m Plastic D IP Package: @, = 75C A att S NJ l4Pin SOIC Package: 8, = 120C Av att = MN z 20 2 NJ 14-PIN DIP PACKAGE ORDERING GUIDE a MN g aS Temperature | Package Package 7S ~Y NY M odel Range Description Options = hs. NY 2 14-PIN sole | Ms AD 8013AN 40C to+ 85C | 14Fin Plastic DB |N-14 2 in AD 8013AR-14 -40C to +85C | L4-Piin Plastic So Ic [R14 2 SN AD 8013AR-14-REEL | -40C to +85C |14Pin Plastic SOT |R-14 3 P| AD 8013AR-14-REEL? | -40C to +85C | 144 in Plastic SO I | R-14 > AD 8013ACH PS A0C to 485C | D ie Foun * 350 40-30-20 -10 0 10 20 30 40 50 60 70 80 30 AMBIENT TEMPERATURE C Maximum Power Dissipation vs. Ambient Temperature REV. A -3-AD8013 METALIZATION PHOTO C ontact factory for latest dim ensions. TD mensions shown in inchesand tm). +iN1 Wy DISABLE 3 5 3 -IN1 6 2 DISABLE 2 OUT1 7 1 DISABLE 1 0.044 (1.13) 14 OUT2 OUT3 3 -IN3 9 4IN3 0.074 (1.81) CAUTION ESD felectrostatic discharge) sensitive device. Electrostatic charyjes as high as 4000 V readily accum ulate on the hum an bedy and test equipm ent and can discharge w tthout detection .A though WARNING! es the AD $013 featurespropretary ESD protection circu try, perm anentdam agem ay occuroen devices oa sub cted to high energy electrostatic discharges. Therefore, proper ESD precautions are recom mended te avoid perform ance degradation or less of functionality. ESD SENSITIVE DEVICE 6 12 4 Y~ oo 75 210 LL I a No LOAD w > 2 & ZA a 4 z 8 yA o 5 1 RL = 1500 Ba 6 a a g 5 7 d g o = z GY 3 5 = 1 o2 = o oO Q o 1 2 3 4 5 6 7 1 2 3 4 6 7 SUPPLY VOLTAGE + Volts SUPPLY VOLTAGE + Volts Figure 1. Input Common-Mode Voltage Range vs. Figure 2. Output Voltage Swing vs. Supply Voltage Supply Voltage 4- REV. AAD8013 10 2 Vg = t5 a al > ra 1 LW] 3g "1 Bs 4 lu g BE 8 4 5 Lt | Vg = 45 5 a Q 10 400 4k 10k LOAD RESISTANCE Figure 3. Output Voltage Swing vs. Load Resistance 12 \ \ 1 Etc AM = pL Le : 3 A a 2 |/ 1 / 6 -60 -40 -20 o 20 40 60 60 100 120 140 JUNCTION TEMPERATURE C Figure 4. Total Supply Current vs. Junction Temperature Ty = 425C SUPPLY CURRENT mA o 3 1 2 3 4 5 6 7 SUPPLY VOLTAGE- + Volts Figure 5. Supply Current vs. Supply Voliage REV. A _ INPUT BIAS CURRENT pA l = o bb +ie -3 -60 -40 -20 a 20 40 60 go 100 120 140 JUNCTION TEMPERATURE C Figure 6. Input Bias Current vs. Junction Temperature > = | a oO a a 3 7 == bi | B | De E 5 | Vga ih z +... _ ee 4 -0 -40 -20 o 20 40 60 80 #6100 120 140 JUNCTION TEMPERATURE C Figure 7. Input Offset Voltage vs. Junction Temperature 140 MS Vg=t5V a @ 130 I 5 I\gou RCE Fa i 420 3 we N\ E 5 SINK | 2 100 I 3 kb g MN & 90 80 -60 -40 -20 o 20 40 60 80 6100 120 140 JUNCTION TEMPERATURE C Figure 8. Short Circuit Current vs. Junction Tem peratureAD8013 = = o _ _ o o roe CLOSED-LOOP OUTPUT RESISTANCE 22 o 0.04 100k 1M 10M 100M 1G FREQUENCY Hz Figure 9. Closed-Loop Output Resistance vs. Frequency 100k 10k OUTPUT RESISTANCE - 2 = _ o o 1M 10M 100M 1G FREQUENCY Hz Figure 10. Oufpui Resistance vs. Frequency, Disabled State 4k = o a VOLTAGE NOISE nv/VHz s CURRENT NOISE pa/VHz 100 1k 10k 100k 1M FREQUENCY Hz Figure ?f. input Current and Voltage Noise vs. Frequency 70 60 50 BN 40 N 30 AN 20 COMMON-MODE REJECTION dB NL 10 100k 1M 10M 100M 1G FREQUENCY Hz Figure 12. Common-Mode Rejection vs. Frequency POWER SUPPLY REJECTION dB 100k 1M 10M 100M 1G FREQUENCY Hz Figure 13. Power Supply Rejection Ratio vs. Frequency 140 o b a ho o b oa PHASE Degrees 135 a o o -180 TRANSIMPEDANCE dB co o a o 40 10k 100k 1M 10M 100M 1G FREQUENCY Hz Figure 14. Qpen-Loop Transimpedance vs. Frequency (Relative to 7Q) REV. AAD8013 -30 g 40 o & Ef a -50 90 4 ' tL z 60 41 180 T= 3 a & -70 -270 g =o =x f -80 ay-1 a on = ag 100 -3 E He 7 440 93 4 of 120 - Ry, = 1500 1k 10k 100k 1M 10M 100M ow 10M 100M 1G FREQUENCY Hz FREQUENCY Hz Figure 15. Harmonic Distortion vs. Frequency Figure 18 Closed-Loop Gain and Phase vs. Frequency, Ga=rl, Ry, = 1500 1800 1600 1400 21200 > f 1000 3 = 800 W mm 600 400 200 1 2 3 4 5 6 T 8 1.5 25 3.5 45 .5 6.5 75 OUTPUT STEP SIZE -V p-p SUPPLY VOLTAGE +Volts Figure 16. Slew Rate vs. Output Step Size Figure 19. Maximum Slew Rate vs. Supply Voltage Figure 17. Large Signal Pulse Response, Gain = +1, Figure 20. Smal! Signal Pulse Response, Gain = +1, (Re = 2kQ, Ry = 150, Vs =+5 V) (Re = 2kQ, Ry = 150 0, Vs = +5 V) REV. A _7-a POCA SATE Se EEE TAT cee Figure 27. Large Signal Pulse Response, Gain = +70, Figure 24. Large Signal Pulse Response, Gain =1, Re = 301 2, Ry = 150.2, Ve =+5 V) (Re = 698 Q, R, = 150 8, Vs = +5 V) wo 3 g 2 190 5 a a | 90 | 1 f K + z +1 0 5 Ww Wu mn -90 zg $ zm" 2 a1 -1 a gi1-1 o oA a8 on 8H Jo qZa a3 ~ Az es o8 4 oz oz - 5 -6 6 4M 40M 100M 1G 1M 10M 100M 1G FREQUENCY Hz FREQUENCY Hz Figure 22. Closed-Loop Gain and Phase vs. Frequency, Figure 25. Closed-Loop Gain and Phase vs. Frequency, G=+70, R, = 1500 G=-1, A, = 15009 | _ ae AC a a ee Figure 23. Small Signal Pulse Response, Gain = +10, Figure 26. Small Signal Pulse Response, Gain = 1, (R- = 301 0, R, = 150 2, Ve= +5 V) (Re = 698 O, R, = 150, Vg =+5 V) -8- REV. AAD8013 + = oa PHASE SHIFT Degrees 4 CLOSED-LOOP GAIN (NORMALIZED) - dB 6b kh b&b ob a = 10M 100M 1G FREQUENCY Hz Figure 27. Closed-Loop Gain and Phase vs. Frequency, G=-10, R, = 1500 General The AD 8013 isa wide bandw idth, tripk video am plifer that offers a high Bvelofperiom ance on kessthan 4.0mA per am pliter of quiescent supply current. The AD 8013 usesa proprietary enhancem ent of a conventional current feedback architecture, and achieves bandwidth in excess of 200M H zwith Jow citterential gain and phase errors, m aking it an extrem ely efficient video am p lifer. The AD 8013sw ide phase m argin coupled with a high output short circuit curentm ake titan excellent choice when drying any capacitive load.H igh open-loop gam and low nvertng Input bias current enab it to be used w ith large vahies of feecback resistor with very low closed-loop gam enor. Tt is designed to oter outstanding functionality and perform ance at Closed-bop Invertng ornonmnvertng gans of one or greater. Choice of Feedback & Gain Resistors Because it is a current tpedback am plifier, the closedbop band- width ofthe AD 8013 m ay be custom ized usng diterent values ofthe feedback resistor. T able I shows typical bandw idths at ditterent supply voltages for som e useful clsed-bop gains when driving a load of 1502. T he choice of feedback resistor is not critical un Jess it is am portant to m amtain the w idest, flattest frequency response. T he resistors recom m ended wn the table are those (chip resistors) that w illresult in the widest 0.1 dB bandw idth w thout peaking. In applications requiring the best controloft bandw idth, 1% resistors are adequate. Package parasitics vary between the 14-pn plastic D P and the 14-pin plastic SO IC, andm ay result tn a shght citterence in the valle of the feedback resistor used to achieve the opin um dynam ic perform ance. Resistor valies and widest bandw idth figures are shown mn parenthesis ir the SO Ic where they diter trom those ottheD P.W ider bandw icdths than those in the table can be attamed by reducing the m agnitide of the feedback resistor (at the expense of Increased peaking), while peaking can be reduced by increasing the m agnitude of the ikedback resistor. Increasing the teedback resistor is especially usetulwhen dranng Jarge capacitive loads as it w ill ncrease the phasem argin ot the closed-loop circuit. (Reterto the section on driving capacitive Joads form ore Intom ation .) REV. A _9- To estim ate the -3 dB bandwidth tor closedbop gams of2 or greater, for feedback resistors not Listed in the to low ing tabk, the tolow ng smgk polem cdelfrtie AD 6013 may be used: G ~ 14+ 8C, (Re +Gn rin) Cy = transcapacttance = 1 pF Ae = tbedback resistor G= idealclsed loop gain ACL where: Ar Gn = TR = noise gan rin = inverting input resistance = 1500 ACL = closed bop gain The -3 dB bandw icth ts determ ined from thism edelas: 1 &~ 30, (A, + Gnrim T his m odelw il predict -3 dB bandw idth te w ithm about 10% to 15% ofthe correct value when the load 181509 andV.= +5 V .For lower supply voltages there w illbe a slight decrease in bandwidth. Them odeLlis not accurate enough to precict either the phase behavior or the frequency response peaking ofthe AD 8013. Tt should be noted that the bandw idth Js attected by attenuation due to the fnite input resistance. AJso, the open-loop output resistance of about 12 9 reduces the bandw idth som ewhat when driving bad resistors less than about 250 . (Bandw idths will be about 10% greater for load resistances above a few hundred ohm s.} Table!. -3 dB Bandwidth vs. Closed-Loop Gain and Feedback Resistor, R_ = 150 (SOIC) V;Volts Gain R--Ohms BW -MHz +5 +1 2000 230 +2 $45 (931) 150 (135) +10 301 50 -1 698 (825) 140 (130) -10 49g 85 +5 +1 2000 180 +2 $87 (931) 120 (130) +10 301 TS -1 698 (825) 130 (120) -10 499 50 Driving Capacitive Loads W hen used in com bination with the appropriate feedback resistor, the AD 8013 willdrive any Joad capacitance w itheut oscillation. T he generalruk forcurrent feedback. am p lifters is that the higher the load capacitance, the higher the feedback resistor required tpr stable operation. D ue to the high open-bep transresistance and low nvertng Input current ofthe AD 8013, the us ofa large teecback resistor does not reaultin brge cloaed- bop gaan errors. A dcitionaly, its fuigh output short circuit cunent m akes possible rapid voltage slew Ing on large bad capacitors. Forthe best com bination of wide bandw idth and clean pulse response, a an all output series resistor js also recom m ended. Tabk I contains valves of feedback. and series resistors which result in the best pulse responses. Figure 29 shows the AD 8013 driving a 300 pF capacitor through a large voltage step with virally no overshoot. (In this case, the Jarye and an allainal pulse responses are quite sm ilar m appearance.)Asnoted in the waming under M aximum PowerD isstipation, ahigh levelofimput overdrive in a high nenmvertng gain circuit can result mn a large current flow in the Input stage. T hough this 150 current is Intemaly Im ited to about 30 mA, its effect on the 0 Yo totalpower dissipation m ay be significant. . 5" High Performance Video Line Driver Atagan of +2, the AD 8013 makes an excellentdrweribra back tem inated 75 Q video lne @ gures 31, 32, and 33). Low diferential gain and phase errors and wide 0.1 dB bandwidth can be realized. The low gain and group delay m atching erors ensure excellent perform ance n RGB system s. Figures 34 and 35 show the worst case m atching. Figure 28. Circuit for Driving a Capacitive Load Table I]. Recommended Feedback and Series Resistors vs. Capacitive Load and Gain Rs -Ohms C_- pF R--Ohms G=2 G23 20 2k 25 15 750 50 2k 25 15 70 , 100 3k 20 15 50 200 4k 15 15 300 6k 15 15 >500 Tk 15 15 Figure 31. A Video Line Driver Operating at a Gain of +2 (Ae = Ag from Table !) o -180 -270 PHASE SHIFT Degrees l = & Figure 29. Pulse Response Driving a Large Load Capacitor. G, = 300 pF, G= +2, Ar = 6k, Rg = 159 Overload Recovery T he three m portant overload conditions are: Input comm on- 10M 100M 1G m ode voltage overdrive, output vo lage overdrive, and input FREQUENCY Fz current overdrive. W hen configured ibra low closed-loop gam, the am plifterw ill quickly recover from an Input comm on- m ode voltage overdrive; typically In under 25 ns.W hen con- figured ibra higher gain, and overloaded at the output, the recovery tm ew illalso be short. Forexam ple, In a gam of+10, with 15% overdrive, the recovery tm eotthe AD 8013 is about 20 ns (see Figure 30). For higher overdrive, the response is som ewhat sbwer.For dB overdrive, (mn agam of+10), the recovery tm e isabout65 ns. CLOSED-LOOP GAIN (NORMALIZED) dB he kh | am = Figure 32. Closed-Loop Gain & Phase vs. Frequency for the Line Driver NORMALIZED GAIN- dB 1M 10M 100M 1G FREQUENCY Hz Figure 33. Fine-Scale Gain Flatness vs. Frequency, G=+2,R, = 1500 Figure 30. 15% Overload Recovery, G= +10 (Ar = 300 0, FA, = 7 kO, Ve = +5 V) 10- REV. AAD8013 G=+2 Ry = 1500 os 4 g=Ht5V 05 I Vg = i5 ~ / GAIN MATCHING dB 1M 10M 100M 1G FREQUENCY Hz Figure 34. Closed-Loop Gain Matching vs. Frequency Gr=4+2 R, = 1508 Vg =t5 G=4+2 A, = 1502 GROUP DELAY ns DELAY MATCHING 100k 1M 10M 100M FREQUENCY Hz Figure 35. Group Delay and Group Delay Matching vs. Frequency, G=+2, Ry = 1500 Disable Mode Operation Pulling the voltage on any one oftheD abl pnsaboutl16Vv up from the negative supply will put the corresponding am plifier Into a disabled, powered down, state. In this condition, the am plifer's quiescent current drops to about O.3mA, its outputbecom esa high mm pedance, and there is a tuigh levelofisolaten from input to output. In the case of the gain of two ine driver torexam pk, the im pedance at the output nede w ibe about the same as bra l.6 kQ resistor (the feedback plus gain resistors) in parallelwith al2 pF capacitor and the input to output isolation willbe about 66 dB atS MHz. Leaving the D isable pin disconnected (floatng) will eave the comespond ing am plifier operational, in the enabled state. The input im pedance ofthe disable pin is about 40 kO an paralelw ith a few picofarads.W hen driven to 0 V, with the negative supply at-5 V, about 100 WA flows nto the cisabl pin. W hen the disable pins are driven by com pm entary output CMOS bgic, on asnge> V suppl, the disabk and enabke tm es are about 50 ns.W hen operated on dualsupples, Jevel shitting willbe required from standard logic outputs to the D isabk pins. F igure 36 show s one possibk m ethod whiich results in a neglgib ke increase in switching tme. REV. A aa > +5 < bk-< = TO DISABLE PIN 10k -5v 4k3 , HIGH => AMPLIFIER ENABLED , LOW = AMPLIFIER DISABLED Figure 36. Level Shifting to Drive Disable Pins on Dual Supplies The AD 8013's Input stages Include protection from the Janje ditterential Input voltages thatm ay be app led when disabled. Tntemalclam ps Im itthis voltage to about $3 V.The high mputto output isolation willbem amtawned for voltages below this lm it. 3:1 Video Multiplexer W inng the am pliter outputs togetherwilipm a3:lmuxwith excellent sw itching behavior. F igure 37 show sa recom m ended con figuration which results in -0.1 dB bandwidth of 35M Hz and OFF channel isolation of 60 dB atlOM Hzont5V supplies. The tm eto switch between channels is about 50 ns. Sw ticking tim Js virtually unatected by signal level BE502 8450. 84G, AAA " Vint DISABLE 10 B50. B45. 75k. CABLE WW Vour 750, DISABLE 2 O BES&2 8450, B40. AAA vw DISABLE 3 0 Figure 37. A Fast Switching 3:1 Video Mux (Supply Bypassing Not Shown) Figure 38. Channel Switching Characteristic for the 3:1 Mux -1i-AD8013 2:1 Video Multiplexer C on figuring two am pliters as unity gain follow ers and using the third te set the gain results in a high perform ance 2:1 mux (Figures 39 and 40). T his ctroutt takes advantage of the very low crosstalk between C hannels 2 and 3 to achieve the OF F channel isolation shown In Figure 40. T his ctreuit can achieve differential gain and phase of 0.03% and 0.07 respectively. DISABLE Figure 39. 2:1 Mux with High Isolation and Low Differential Gain and Phase Errors 2 1 a 7 -1 z a2 6 -3 a a a a 4 7 WW x gs g a FEEDTHROUGH a 6 a _ a 7 WW Le -8 iM 10M 100M 1G FREQUENCY Hz Figure 40. 2:1 Mux ON Channel Gain and Mux OFF Channel Feedthrough vs. Frequency Gain Switching TheAD 8013 can be used to build a cireuit ior sw itching between any two arbitrary gains whilem antaining a constant mput Im pedance. T he exam ple of F igure 41 show s a ctroutt for sw itching between a noninverting gan of 1 and an Invertng gan of 1. The totaltim e for channel sw itching and output voltage settling is about 80 ns. 6880 G98) Figure 42. Switching Characteristic for Circuit of Figure 41 OUTLINE DIMENSIONS D mensions shown in inchesand tmm)}. 14-Lead Plastic DIP (N-14) 14-Lead SOIC (R-14) 0.795 (20.19) O34 (8.75) 072s (18.4 42) 0.9367 (6.55) ; AAA if t 8 0.280 (7.11) 0.1574 (4.00) i" *) o.2aa0 (6.20) . 7 ozo (6.10) 0.1497 (3.80) [T1 7 |) 02284 (6.80) Too oo 0.325 (8.25) I 0.060 (1.52) 0.300 (7.62) 9.195 (4.95) HRY HHH Hd PIN 1 0.015 (0.38) 0.115 (2.93) PIN4 0.0688 (1.75) 0.0196 (0.50) 0.210 (5.33) t 0.0098 (0.25) 0.0532 (1.35) *| [* 0.0099 0.25)" MAX gM et et eet te 0.130 0.0040 (0.10) 0.160 (4.06) i ery (3.30) + TED OT -- IN oe ote 0.115 (2.93) ete SEATING 0.015 (0.381) p.0500 0.0192 (0.49) cz = ole 0.022 (0.558) 0.100 0.070 (1.77) PLANE D.008 (0.204) SEATING (1.27) 10738 (0.45) 0.0098 (0.25) 0.0500 (1.27) 0.074 (0.356) 254) 0.045 (1.15) PLANE BSC , , 0.0075 (0.19) 0.0760 (0.41) -12- REV. A C2084-18-10/95 PRINTED IN U.S.A.