boldfaceios8.1.3

CONNECTIONDIAGRAMSTO-99(H)PackageAD70776281345NULLNULL–IN+IN–VS+VSOUTPUTNCNC=NOCONNECTNOTE:PIN4CONNECTEDTOCASEPlastic(N)andCerdip(Q)PackagesSOIC(R)PackageREV.
BInformationfurnishedbyAnalogDevicesisbelievedtobeaccurateandreliable.
However,noresponsibilityisassumedbyAnalogDevicesforitsuse,norforanyinfringementsofpatentsorotherrightsofthirdpartieswhichmayresultfromitsuse.
NolicenseisgrantedbyimplicationorotherwiseunderanypatentorpatentrightsofAnalogDevices.
aUltralowDriftOpAmpAD707AnalogDevices,Inc.
,1995OneTechnologyWay,P.
O.
Box9106,Norwood,MA02062-9106,U.
S.
A.
Tel:617/329-4700Fax:617/326-8703FEATURESVeryHighDCPrecision15VmaxOffsetVoltage0.
1V/CmaxOffsetVoltageDrift0.
35Vp-pmaxVoltageNoise(0.
1Hzto10Hz}8V/VminOpen-LoopGain130dBminCMRR120dBminPSRR1nAmaxInputBiasCurrentACPerformance0.
3V/sSlewRate0.
9MHzClosed-LoopBandwidthDualVersion:AD708AvailableinTapeandReelinAccordancewithEIA-481AStandardAPPLICATIONHIGHLIGHTS1.
TheAD707's13V/Vtypicalopen-loopgainand140dBtypicalcommon-moderejectionratiomakeitidealforprecisioninstrumentationapplications.
2.
TheprecisionoftheAD707makestightererrorbudgetspossibleatalowercost.
3.
ThelowoffsetvoltagedriftandlownoiseoftheAD707allowthedesignertoamplifyverysmallsignalswithoutsacrificingoverallsystemperformance.
4.
TheAD707canbeusedwherechopperamplifiersarerequired,butwithouttheinherentnoiseandapplicationproblems.
5.
TheAD707isanimprovedpin-for-pinreplacementfortheLT1001.
PRODUCTDESCRIPTIONTheAD707isalowcost,highprecisionopampwithstate-of-the-artperformancethatmakesitidealforawiderangeofprecisionapplications.
Theoffsetvoltagespecoflessthan15Visthebestavailableinabipolaropamp,andmaximuminputoffsetcurrentis1.
0nA.
Thetopgradeisthefirstbipolarmonolithicopamptoofferamaximumoffsetvoltagedriftof0.
1V/°C,andoffsetcurrentdriftandinputbiascurrentdriftarebothspecifiedat25pA/°Cmaximum.
TheAD707'sopen-loopgainis8V/Vminimumoverthefull±10Voutputrangewhendrivinga1kload.
Maximuminputvoltagenoiseis350nVp-p(0.
1Hzto10Hz).
CMRRandPSRRare130dBand120dBminimum,respectively.
TheAD707isavailableinversionsspecifiedovercommercial,industrialandmilitarytemperatureranges.
Itisofferedin8-pinplasticmini-DIP,smalloutline(SOIC),hermeticcerdipandhermeticTO-99metalcanpackages.
Chips,MIL-STD-883B,Rev.
C,andtape&reelpartsarealsoavailable.
12348765AD707NC=NOCONNECTNULLNCOUTPUT+VSNULL–IN+IN–VSAD7071485NC=NOCONNECTNULLNCOUTPUT+VSNULL–IN+IN–VSOBSOLETEAD707–SPECIFICATIONSREV.
B–2–(@+25Cand15V,unlessotherwisenoted)AD707J/AAD707K/BConditionsMinTypMaxMinTypMaxUnitsINPUTOFFSETVOLTAGEInitial30901025Vvs.
Temperature0.
31.
00.
10.
3V/°CTMINtoTMAX501001545VLong-TermStability0.
30.
3V/monthAdjustmentRangeR2=20k(Figure19)±4±4mVINPUTBIASCURRENT1.
02.
50.
52.
0nATMINtoTMAX2.
04.
01.
54.
0nAAverageDrift15401540/40/40pA/°COFFSETCURRENTVCM=0V0.
52.
00.
31.
5nATMINtoTMAX2.
04.
01.
02.
0nAAverageDrift240125/25/35pA/°CINPUTVOLTAGENOISE0.
1Hzto10Hz0.
230.
60.
230.
6Vp-pf=10Hz10.
32810.
318nV/√Hzf=100Hz10.
013.
010.
012nV/√Hzf=1kHz9.
611.
09.
611.
0nV/√HzINPUTCURRENTNOISE0.
1Hzto10Hz14351430pAp-pf=10Hz0.
320.
90.
320.
8pA/√Hzf=100Hz0.
140.
270.
140.
23pA/√Hzf=1kHz0.
120.
180.
120.
17pA/√HzCOMMON-MODEREJECTIONRATIOVCM=±13V120140130140dBTMINtoTMAX120140120140dBOPEN-LOOPGAINVO=±10VRLOAD≥2k313513V/VTMINtoTMAX313313V/VPOWERSUPPLYREJECTIONRATIOVS=±3Vto±18V110130115130dBTMINtoTMAX110130110130dBFREQUENCYRESPONSEClosed-LoopBandwidth0.
40.
90.
40.
9MHzSlewRate0.
120.
30.
120.
3V/sINPUTRESISTANCEDifferential2410045200MCommonMode200300GOUTPUTCHARACTERISTICSVoltageRLOAD≥10k13.
51413.
514±VRLOAD≥2k12.
513.
012.
513.
0±VRLOAD≥1k12.
012.
512.
012.
5±VRLOAD≥2kTMINtoTMAX12.
013.
012.
013.
0±VOPEN-LOOPOUTPUTRESISTANCE6060POWERSUPPLYCurrent,Quiescent2.
532.
53mAPowerConsumption,NoLoadVS=±15V75907590mWVS=±3V7.
59.
07.
59.
0mWNOTESAllminandmaxspecificationsareguaranteed.
Specificationsinboldfacearetestedonallproductionunitsatfinalelectricaltest.
Resultsfromthosetestsareusedtocalculateoutgoingqualitylevels.
Specificationssubjecttochangewithoutnotice.
OBSOLETEAD707REV.
B–3–ABSOLUTEMAXIMUMRATINGS1SupplyVoltage22VInternalPowerDissipation2500mWInputVoltageVSOutputShortCircuitDurationIndefiniteDifferentialInputVoltageVSand–VSStorageTemperatureRange(Q,H)65°Cto+150°CStorageTemperatureRange(N,R)65°Cto+125°CLeadTemperatureRange(Soldering60sec)300°CNOTES1Stressesabovethoselistedunder"AbsoluteMaximumRatings"maycausepermanentdamagetothedevice.
Exposuretoabsolutemaximumratingcondi-tionsforextendedperiodsmayaffectdevicereliability.
28-pinplasticpackage:θJA=165°C/Watt;8-pincerdippackage:θJA=110°C/Watt;8-pinsmalloutlinepackage:θJA=155°C/Watt;8-pinheaderpackage:θJA=200°C/Watt.
ORDERINGGUIDETemperaturePackagePackageModelRangeDescriptionOptionAD707AH–40°Cto+85°C8-PinMetalCanH-08AAD707AQ–40°Cto+85°C8-PinCeramicDIPQ-8AD707AR–40°Cto+85°C8-PinPlasticSOICSO-8AD707AR-REEL–40°Cto+85°C8-PinPlasticSOICSO-8AD707AR-REEL7–40°Cto+85°C8-PinPlasticSOICSO-8AD707BQ–40°Cto+85°C8-PinCeramicDIPQ-8AD707JN0°Cto+70°C8-PinPlasticDIPN-8AD707JR0°Cto+70°C8-PinPlasticSOICSO-8AD707JR-REEL0°Cto+70°C8-PinPlasticSOICSO-8AD707JR-REEL70°Cto+70°C8-PinPlasticSOICSO-8AD707KN0°Cto+70°C8-PinPlasticDIPN-8AD707KR0°Cto+70°C8-PinPlasticSOICSO-8AD707KR-REEL0°Cto+70°C8-PinPlasticSOICSO-8AD707KR-REEL70°Cto+70°C8-PinPlasticSOICSO-8METALIZATIONPHOTOGRAPHDimensionsshownininchesand(mm).
Contactfactoryforlatestdimensions.
0.
059(1.
51)NULL8+VS76VOUT4–VS3+IN2–IN1NULL0.
110(2.
79)WARNING!
ESDSENSITIVEDEVICECAUTIONESD(electrostaticdischarge)sensitivedevice.
Electrostaticchargesashighas4000Vreadilyaccumulateonthehumanbodyandtestequipmentandcandischargewithoutdetection.
AlthoughtheAD707featuresproprietaryESDprotectioncircuitry,permanentdamagemayoccurondevicessubjectedtohighenergyelectrostaticdischarges.
Therefore,properESDprecautionsarerecommendedtoavoidperformancedegradationorlossoffunctionality.
OBSOLETEAD707–TypicalCharacteristicsREV.
B–4–SUPPLYVOLTAGE–±V+VS–1.
5–VS0255101520–0.
5–1.
0+1.
5+0.
5+1.
0+VOUT–VOUTOUTPUTVOLTAGESWING–±V(REFERREDTOSUPPLYVOLTAGES)RL=2k@+25°CFigure2.
OutputVoltageSwingvs.
SupplyVoltageOFFSETVOLTAGEDRIFT–V/°CNUMBEROFUNITS1007020–0.
4–0.
30.
4–0.
2–0.
100.
10.
20.
3908050306040100256UNITSTESTED–55°CTO+125°CFigure5.
TypicalDistributionofOffsetVoltageDriftFREQUENCY–Hz454000.
010.
11001103530252015105INPUTVOLTAGENOISE–nV/√HzI/FCORNER0.
7HzFigure8.
InputNoiseSpectralDensityLOADRESISTANCE–OUTPUTVOLTAGE–Vp-p351501010010k1k102520305±15VSUPPLIESFigure3.
OutputVoltageSwingvs.
LoadResistanceFREQUENCY–HzOUTPUTIMPEDANCE–1000.
00010.
1100k1101001k10k1010.
10.
0010.
01IO=1mAAV=+1000AV=+1Figure6.
OutputImpedancevs.
Frequency100%10090TIME–1sec/DivVOLTAGENOISE–100nV/DivFigure9.
0.
1Hzto10HzVoltageNoiseSUPPLYVOLTAGE–±V+VS–1.
5–0.
5–1.
0–VS+1.
5+0.
5+1.
00255101520+V–VCOMMOM-MODEVOLTAGELIMIT–V(REFERREDTOSUPPLYVOLTAGES)Figure1.
InputCommon-ModeRangevs.
SupplyVoltageTIMEAFTERPOWERON–MinutesCHANGEINOFFSET–V4004123321DUAL-IN-LINEPACKAGEPLASTIC(N)orCERDIP(Q)METALCAN(H)PACKAGEFigure4.
OffsetVoltageWarm-UpDriftDIFFERENTIALVOLTAGE–±V4030001100102010INVERTINGORNONINVERTINGINPUTCURRENT–mAFigure7.
InputCurrentvs.
DifferentialInputVoltageOBSOLETEAD707REV.
B–5–TEMPERATURE–°C16100–60–40140–2002040608010012014126284OPEN-LOOPGAIN–V/VRL=1kVOUT=±10VFigure10.
Open-LoopGainvs.
TemperatureFREQUENCY–HzCOMMON-MODEREJECTION–dB16000.
11101001k10k100k1M14010080602012040Figure13.
Common-ModeRejectionvs.
FrequencySUPPLYVOLTAGE–±VSUPPLYCURRENT–mA4003246912151821213+125°C+25°C–55°CFigure16.
SupplyCurrentvs.
SupplyVoltageSUPPLYVOLTAGE–VOPEN-LOOPGAIN–V/V16100025510152014126284RLOAD=1kFigure11.
Open-LoopGainvs.
SupplyVoltageFREQUENCY–HzOUTPUTVOLTAGE–Vp-p351501k10k1M100k102520305FMAX=3kHzRL=2k+25°CVS=±15VFigure14.
LargeSignalFrequencyResponse20mV/DIVCH1TIME–2s/DIVFigure17.
SmallSignalTransientResponse;AV=+1,RL=2k,CL=50pFFREQUENCY–HzOPEN-LOOPGAIN–V/V1408000.
010.
11101001k10k100k1M10M12010040106020PHASE–Degrees3018009015060120RL=2kCL=1000pFPHASEMARGIN=58°GAINFigure12.
Open-LoopGainandPhasevs.
FrequencyFREQUENCY–HzPOWERSUPPLYREJECTION–dB16000.
0010.
01100k0.
11101001k10k14080604020120100Figure15.
PowerSupplyRejectionvs.
Frequency20mV/DIVCH1TIME–2s/DIVFigure18.
SmallSignalTransientResponse;AV=+1,RL=2k,CL=1000pFOBSOLETEAD707REV.
B–6–OPERATIONWITHAGAINOF100DemonstratingtheoutstandingdcprecisionoftheAD707inpracticalapplications,TableIshowsanerrorbudgetcalculationforthegainof–100configurationshowninFigure21.
TableI.
ErrorBudgetMaximumErrorContributionAv=100(CGrade)ErrorSource(FullScale:VOUT=10V,VIN=100mV)VOS15V/100mV=150ppmIOS(100)(1nA)/100mV=1ppmGain(2kLoad)(100V/8*106)100mV=13ppmNoise0.
35V/100mV=4ppmVOSDrift(0.
1V/°C)/100mV=1ppm/°C=168ppm+1ppm/°CTotalUnadjustedError@+25°C=168ppm>12Bits@–55°Cto+125°C=268ppm>11BitsWithOffsetCalibratedOut@+25°C=17ppm>15Bits@–55°Cto+125°C=117ppm>13Bits623+VSAD7070.
1F–VS499VOUT0.
1F7VIN10k100Figure21.
Gainof–100ConfigurationAlthoughtheinitialoffsetvoltageoftheAD707isverylow,itisnonethelessthemajorcontributortosystemerror.
Incasesrequiringadditionalaccuracy,thecircuitshowninFigure19canbeusedtonullouttheinitialoffsetvoltage.
Thismethodwillalsocanceltheeffectsofinputoffsetcurrenterror.
Withtheoffsetsnulled,theAD707Cwilladdlessthan17ppmoferror.
Thiserrorbudgetassumesnoerrorintheresistorratioandnoerrorsfrompowersupplyvariation(the120dBminimumPSRRoftheAD707Cmakesthisagoodassumption).
Theexternalresistorscancausegainerrorfrommismatchanddriftovertemperature.
OFFSETNULLINGTheinputoffsetvoltageoftheAD707isthelowestavailableinabipolaropamp,butifadditionalnullingisrequired,thecircuitshowninFigure19offersanullrangeof200V.
Forwidernullcapability,omitR1andsubstitutea20kpotenti-ometerforR2.
6238R22k1R110k0.
1F+VS7AD7070.
1F–VS4OFFSETADJUSTFigure19.
ExternalOffsetNullingandPowerSupplyBypassingGAINLINEARITYINTOA1kLOADThegainandgainlinearityoftheAD707arethehighestavailableamongmonolithicbipolaramplifiers.
Unlikeotherdcprecisionamplifiers,theAD707showsnodegradationingainorgainlinearitywhendrivingloadsinexcessof1kovera±10Voutputswing.
Thismeanshighgainaccuracyisassuredovertheoutputrange.
Figure20showsthegainoftheAD707,OP07,andtheOP77amplifierswhendrivinga1kload.
TheAD707willdrive10mAofoutputcurrentwithnosignifi-canteffectonitsgainorlinearity.
OUTPUTVOLTAGE–VCHANGEINOFFSETVOLTAGE–10V/Div–1515–10–50510AD707OP07OP77@+25°CRLOAD=1kFigure20.
GainLinearityoftheAD707vs.
OtherDCPrecisionOpAmpsOBSOLETEAD707REV.
B–7–18-BITSETTLINGTIMEFigure22showstheAD707settlingtowithin80Vofitsfinalvaluefora20Voutputstepinlessthan100s(inthetestcon-figurationshowninFigure23).
Toachievesettlingto18bits,anyamplifierspecifiedtohaveagainof4V/Vwouldappeartobegoodenough,however,thisisnotthecase.
Inordertotrulyachieve18-bitaccuracy,thegainlinearitymustbebetterthan4ppm.
ThegainnonlinearityoftheAD707doesnotcontributetotheerror,andthegainitselfonlycontributes0.
1ppm.
Thegainerror,alongwiththeVOSandVOSdrifterrorsdonotcomprise1LSBoferrorinan18-bitsystemoverthemilitarytemperaturerange.
Ifcalibrationisusedtonulloffseterrors,theAD707resolvesupto20bitsat+25°C.
TIME–50s/DivREFERENCESIGNAL10V/DivD.
U.
T.
OUTPUTERROR50V/DivOUTPUT:10V/DivFigure22.
18-BitSettling–VS623OP27200k2xHP1N6263VERRORx100710F0.
1F+VS10F0.
1F–VS623D.
U.
T.
AD707100710F0.
1F+VS10F0.
1F1.
9k2k42kVINFLAT-TOPPULSEGENERATORDATADYNAMICS5109OREQUIVALENT2k4Figure23.
OpAmpSettlingTimeTestCircuit140dBCMRRINSTRUMENTATIONAMPLIFIERTheextremelytightdcspecificationsoftheAD707enablethedesignertobuildveryhighperformance,highgaininstrumenta-tionamplifierswithouthavingtoselectmatchedopampsforthecrucialfirststage.
Forthesecondstage,thelowestgradeAD707isideallysuited.
TheCMRRistypicallythesameasthehighgradeparts,butdoesnotexactapremiumfordriftperformance(whichislesscriticalinthesecondstage).
Figure24showsanexampleoftheclassicinstrumentationamp.
Figure25showsthatthecircuithasatleast140dBofcommon-moderejectionfora±10Vcommon-modeinputatagainof1001(RG=20).
623A1AD70710k2009.
9kR210k–INR410kRG10kR110k623A3AD707623A2AD707+INR2RCMCIRCUITGAIN1RG20,000Figure24.
A3OpAmpInstrumentationAmplifierHighCMRRisobtainedbyfirstadjustingRCMuntiltheoutputdoesnotchangeastheinputissweptthroughthefullcommon-moderange.
ThevalueofRG,shouldthenbeselectedtoachievethedesiredgain.
MatchedresistorsshouldbeusedfortheoutputstagesothatRCMisassmallaspossible.
ThesmallerthevalueOfRCM,thelowerthenoiseintroducedbypotentiometerwipervibrations.
TomaintaintheCMRRat140dBovera20°Crange,theresistorratiosintheoutputstage,R1/R2andR3/R4,musttrackeachotherbetterthan10ppm/°C.
TIME–2sec/DivCH1CH2INPUTCOMMON-MODESIGNAL:10V/DivCOMMON-MODEERRORREFERREDTOINPUT:5V/DivFigure25.
InstrumentationAmplifierCommon-ModeRejectionOBSOLETEAD707REV.
B–8–C1164a–2–12/95PRINTEDINU.
S.
A.
OUTLINEDIMENSIONSDimensionsshownininchesand(mm).
8-PinMetalCan(H-08A)45°BSC0.
100(2.
54)BSC0.
034(0.
86)0.
027(0.
69)0.
045(1.
14)0.
027(0.
69)0.
160(4.
06)0.
110(2.
79)0.
100(2.
54)BSC0.
200(5.
08)BSC68571423REFERENCEPLANEBASE&SEATINGPLANE0.
335(8.
51)0.
305(7.
75)0.
370(9.
40)0.
335(8.
51)0.
750(19.
05)0.
500(12.
70)0.
045(1.
14)0.
010(0.
25)0.
050(1.
27)MAX0.
040(1.
02)MAX0.
019(0.
48)0.
016(0.
41)0.
021(0.
53)0.
016(0.
41)0.
185(4.
70)0.
165(4.
19)0.
250(6.
35)MIN8-PinCerdip(Q-8)0.
320(8.
13)0.
290(7.
37)0.
015(0.
38)0.
008(0.
20)15°0°0.
005(0.
13)MIN0.
055(1.
4)MAX1PIN14580.
310(7.
87)0.
220(5.
59)0.
405(10.
29)MAX0.
200(5.
08)MAXSEATINGPLANE0.
023(0.
58)0.
014(0.
36)0.
070(1.
78)0.
030(0.
76)0.
060(1.
52)0.
015(0.
38)0.
150(3.
81)MIN0.
200(5.
08)0.
125(3.
18)0.
100(2.
54)BSC8-PinPlasticDIP(N-8)81450.
430(10.
92)0.
348(8.
84)0.
280(7.
11)0.
240(6.
10)PIN1SEATINGPLANE0.
022(0.
558)0.
014(0.
356)0.
060(1.
52)0.
015(0.
38)0.
210(5.
33)MAX0.
130(3.
30)MIN0.
070(1.
77)0.
045(1.
15)0.
100(2.
54)BSC0.
160(4.
06)0.
115(2.
93)0.
325(8.
25)0.
300(7.
62)0.
015(0.
381)0.
008(0.
204)0.
195(4.
95)0.
115(2.
93)8-LeadSOIC(SO-8)0.
1968(5.
00)0.
1890(4.
80)85410.
2440(6.
20)0.
2284(5.
80)PIN10.
1574(4.
00)0.
1497(3.
80)0.
0688(1.
75)0.
0532(1.
35)SEATINGPLANE0.
0098(0.
25)0.
0040(0.
10)0.
0192(0.
49)0.
0138(0.
35)0.
0500(1.
27)BSC0.
0098(0.
25)0.
0075(0.
19)0.
0500(1.
27)0.
0160(0.
41)8°0°0.
0196(0.
50)0.
0099(0.
25)x45°PRECISIONCURRENTTRANSMITTERTheAD707'sexcellentdcperformance,especiallythelowoffsetvoltage,lowoffsetvoltagedriftandhighCMRR,makesitpossibletomakeahighprecisionvoltage-controlledcurrenttransmitterusingavariationoftheHowlandCurrentSourcecircuit(Figure26).
Thiscircuitprovidesabidirectionalloadcurrentwhichisderivedfromadifferentialinputvoltage.
623+VSAD7070.
1F–VS40.
1F7R4100kR3100kR2100kR1100kRLILRSCALEVINVINRSCALEtL()R2R1Figure26.
PrecisionCurrentSource/SinkTheperformanceandaccuracyofthiscircuitwilldependalmostentirelyonthetoleranceandselectionoftheresistors.
Thescaleresistor(RSCALE)andthefourfeedbackresistorsdirectlyaffecttheaccuracyoftheloadcurrentandshouldbechosencarefullyortrimmed.
Asanexampleoftheaccuracyachievable,assumeILmustbe10mA,andtheavailableVINisonly10mV.
RSCALE=10mV/10mA=1IERRORduetotheAD707C:MaximumIERROR=2(VOS)/RSCALE+2(VOSDrift)/RSCALE+IOS(100k/RSCALE)=2(15V)/l+2(0.
1V/°C)/l+1nA(100k)/l(1.
5nA@125°C)=30A+0.
2A/°C+100A(150A@125°C)=130A/10mA=1.
3%@25°C=180A/10mA=1.
8%@125°CLowdrift,highaccuracyresistorsarerequiredtoachievehighprecision.
OBSOLETE