LMC662 CMOS Dual Operational Amplifier datasheet (Rev. C)

1 APRIL1998 REVISEDMARCH2013 LMC662 CMOSDualOperationalAmplifierCheckforSamp les:LMC6621 FEATURESDESCRIPTIONTheLMC662 CMOSD ualoperationalamplifieris2 Rail-to-RailOutputSwingidealforoperation froma operates Specifiedfor2 k and600 Loadsfrom+5 Vto+15 Vandfeaturesrail-to-railoutput LowInputOffsetVoltage:3 mVhaveplaguedCMOS amplifiersinthepastarenota V/ ,drift,and UltraLowInputBiasCurrent:2 fAbroadbandnoiseaswellasvoltagegainintor ealisticloads(2k and600 ) areallequaltoorbetterthan InputCommon-ModeRangeIncludesV widelyacceptedbipolarequivalents.

2 OperatingRangefrom+5 Vto+15 VSupplyThischipisbuiltwithTI'sadvancedDo uble-Poly ISS= 400 A/ Amplifier ;IndependentofV+Silicon-GateC MOS process. High-ImpedanceBufferorPreamplifier PrecisionCurrent-to-VoltageConverter Long-TermIntegrator Sample-and-HoldCircuit PeakDetector MedicalInstrumentation IndustrialControls , ,standardwarranty,andusein 1998 2013, APRIL1998 (1)(2)(3)DifferentialInputVoltage SupplyVoltageSupplyVoltage(V+ V )16 VOutputShortCircuittoV+See(4)OutputShort CircuittoV See(5)LeadTemperature(Soldering,10sec.)

3 260 65 C to+150 CVoltageatInput/OutputPins(V+) + ,(V ) 18mACurrentatInputPin 5 mACurrentatPowerSupplyPin35mAPowerDissip ationSee(6)JunctionTemperature150 CESDT olerance(7)1000V(1) intendedtobefunctional, , (2)A militaryRETS electricaltestspecificationis availableonrequest.(3)If Military/Aerospacespecifieddevicesarereq uired,pleasecontacttheTISalesOffice/Dist ributorsforavailabilityandspecifications .(4)DonotconnectoutputtoV+whenV+is greaterthan13 Vorreliabilitymaybeadverselyaffected.(5) exceedingthemaximumallowedjunctiontemper atureof150 excessof 30mAoverlongtermmayadverselyaffectreliab ility.

4 (6)Themaximumpowerdissipationis a functionofTJ(max), JA, andTA. Themaximumallowablepowerdissipationatany ambienttemperatureis PD= (TJ(max) TA)/ JA.(7)Humanbodymodel, in (1)TemperatureRangeLMC662AI 40 C TJ +85 CLMC662C0 C TJ +70 (2)ThermalResistance( JA)(3)8-PinPDIP101 C/W8-PinSOIC165 C/W(1) intendedtobefunctional, , (2)Foroperatingatelevatedtemperaturesthe devicemustbederatedbasedonthethermalresi stance JAwithPD= (TJ TA)/ JA.(3)Allnumbersapplyforpackagessoldered directlyintoa 1998 2013, APRIL1998 REVISEDMARCH2013 DCElectricalCharacteristicsUnlessotherwi sespecified,alllimitsensuredforTJ= 25 += 5V,V =0V,VCM= ,VO= > (1)UnitsLimit(1)Limit(1) V/ >1 Tera CommonMode0V VCM += 15V6862minPositivePowerSupply5V V+ 15V837063dBRejectionRatioVO= V 10V948474dBRejectionRatio8373minInputCom mon-ModeV+= 5V& 15V 50dB00maxV+ + + + + 2 k (2)2000440300V/mVVoltageGainSourcing4002 00minSinking50018090V/mV12080minRL= 600 (2)

5 1000220150V/mVSourcing200100minSinking10 050V/mV2506040minOutputSwingV+= 2 k toV+ += 600 toV+ += 2 k toV+ += 600 toV+ (1) (2)V+= 15V,VCM= , VO , VO 1998 2013,TexasInstrumentsIncorporatedSubmitD ocumentationFeedback3 ProductFolderLinks: LMC662 LMC662 SNOSC51C APRIL1998 (continued)Unlessotherwisespecified,alll imitsensuredforTJ= 25 += 5V,V =0V,VCM= ,VO= > (1)UnitsLimit(1)Limit(1)OutputCurrentSou rcing,VO= 0V221613mAV+= 5V1411minSinking,VO= 5V211613mA1411minOutputCurrentSourcing,V O= 0V402823mAV+= 15V2521minSinking,VO= 13V392823mASee(3) (3)DonotconnectoutputtoV+whenV+is ,alllimitsensuredforTJ= 25 += 5V,V =0V,VCM= ,VO= > (1)UnitsLimit(1)Limit(1)SlewRateSee(2) (3)

6 130dBInput-ReferredVoltageNoiseF = 1 kHz22nV HzInput-ReferredCurrentNoiseF = 1 HzTotalHarmonicDistortionF = 10kHz,AV= 10RL= 2 k , VO= 8 += 15V(1) (2)V+= theslowerofthepositiveandnegativeslewrat es.(3) += 15 VandRL= 10k connectedtoV+ turnwith1 kHztoproduceVO= 1998 2013, APRIL1998 REVISEDMARCH2013 TypicalPerformanceCharacteristicsVS= ,TA= 25 C 1998 2013,TexasInstrumentsIncorporatedSubmitD ocumentationFeedback5 ProductFolderLinks: LMC662 LMC662 SNOSC51C APRIL1998 (continued)VS= ,TA= 25 C :Avoidresistiveloads< 500.

7 Avoidresistiveloads< 500 , 1998 2013, APRIL1998 REVISEDMARCH2013 APPLICATIONHINTSAMPLIFIERTOPOLOGYT hetopologychosenfortheLMC662,showninFigu re15, is unconventional(comparedtogeneral-purpose opamps)inthatthetraditionalunity-gainbuf feroutputstageis notused;instead,theoutputis takendirectlyfromtheoutputoftheintegrato r, ,whilemaintaininghighopampgainandstabili ty,andmustwithstandshortstoeitherrail, resultofthesedemands,theintegratoris a compoundaffairwithanembeddedgainstagetha tis doublyfedforward(viaCfandCff) bya ,theoutputportionoftheintegratoris a , (EachAmplifier)Thelargesignalvoltagegain whilesourcingis comparabletotraditionalbipolaropamps,eve nwitha 600 ,duetotheadditionalgainstage.

8 However,underheavyload(600 ) thegainwillbereducedasindicatedin , , ,thisinputcapacitance(alongwithanyadditi onalcapacitanceduetocircuitboardtraces,t hesocket,etc.)andthefeedbackresistorscre atea polein ,Figure16, thefrequencyofthispoleis(1)where:CSisthe totalcapacitanceattheinvertinginput,incl udingamplifierinputcapacitanceandanystra ycapacitancefromtheICsocket(ifoneis used),circuitboardtraces,etc.,andRPis theparallelcombinationofRFandRIN. Thisformula,aswellasallformulaederivedbe low, fewk , thefrequencyofthefeedbackpolewillbequite high, thefrequencyofthefeedbackpoleismuchhighe rthanthe ideal closed-loopbandwidth(thenominalclosed-lo opbandwidthintheabsenceofCS), thepolewillhavea negligibleeffectonstability,asit willaddonlya 1998 2013,TexasInstrumentsIncorporatedSubmitD ocumentationFeedback7 ProductFolderLinks.

9 LMC662 LMC662 SNOSC51C APRIL1998 ,if thefeedbackpoleis lessthanapproximately6 to10timesthe ideal 3 dBfrequency,a feedbackcapacitor,CF, termsoftheamplifier'slow-frequencynoiseg ain:Tomaintainstability,a feedbackcapacitorwillprobablybeneededif: (2)where:(3)is theamplifier'slow-frequencynoisegainandG BWis theamplifier' 'slow-frequencynoisegainis representedbytheformula:(4) feedbackcapacitoris morelikelytobeneededwhenthenoisegainis lowand/orthefeedbackresistoris theaboveconditionismet(indicatinga feedbackcapacitorwillprobablybeneeded),a ndthenoisegainislargeenoughthat:(5)thefo llowingvalueoffeedbackcapacitoris recommended:(6)If(7)thefeedbackcapacitor shouldbe:(8)Notethatthesecapacitorvalues areusuallysignificantlysmallerthanthoseg ivenbytheolder,moreconservativeformula.

10 (9)CSconsistsoftheamplifier's 1998 2013, APRIL1998 maybenecessaryinanyoftheabovecasestousea somewhatlargerfeedbackcapacitortoallowfo runexpectedstraycapacitance,ortotolerate additionalphaseshiftsintheloop,orexcessi vecapacitiveload,ortodecreasethenoiseorb andwidth, ,a printedcircuitboard'sstraycapacitancemay belargerorsmallerthanthebreadboard's, ,thevalueofCFshouldbecheckedontheactualc ircuit, , ' thispolefrequencyis sufficientlylow,it willdegradetheopamp'sphasemarginsothatth eamplifieris , theadditionofa smallresistor(50 to100 ) inserieswiththeopamp'soutput,anda capacitor(5pFto10pF)frominvertinginputto outputpins,returnsthephasemargintoa , ,theoutputwillringheavilywhentheloadcapa citanceis ,CxImproveCapacitiveLoadToleranceCapacit iveloaddrivingcapabilityisenhancedbyusin ga pullupresistortoV+Figure18.