OPA1656 超低噪声、低失真、FET 输入、Burr-BrownTM

ProductFolderOrderNowDocuments&SoftwareSupport&CommunityOPA1656ZHCSJH0A–MARCH2019–REVISEDJULY201913特性说明•超低噪声：OPA1656是一款Burr-Brown™运算放大器，专门设计–电压噪声：10kHz时为2.9nV/√Hz用于要求信号保真的音频和工业应用。FET输入架构–电流噪声：1kHz时为6fA/√Hz可达到2.9nV/√Hz的低电压噪声密度和6fA/√Hz电流•低失真：噪声密度，能够在各种电路内将噪声降到极低。–1kHz时为0.000029%(–131dB)OPA1656采用高带宽和高开环增益设计，在20kHz时的失真率低至0.000035%(–129dB)并且可提高全

–20kHz时为0.000035%(–129dB)音频带宽内的音频信号保真。该器件还具有出色的输•高开环增益：150dB出电流驱动功能，在Ω负载下提供250mV电源电

•高输出电流：100mA压范围内的轨至轨输出摆幅，并且可以提供100mA输

•低输入偏置电流：10pA出电流。•压摆率：24V/μs•增益带宽积：53MHzOPA1656可在±2.25V至±18V的极宽电源电压范围•轨至轨输出内工作，也可在仅为3.9mA的电源电流（4.5V至•宽电源电压范围：±2.25V至±18V或4.5V至36V•静态电流：每通道3.9mA）下工作，从而可满足许多类型的音频产品的电源限制。它的额定工作温度范围为–40°C至+125°C。该器件采用8引脚SOIC封装。2应用器件信(1)•条形音箱器件型号封装封装尺寸（标称值）•唱盘OPA1656SOIC(8)4.90mm×3.91mm•DJ控制器、混频器和其他DJ设备(1)如需了解所有可用封装，请参阅数据表末尾的封装选项附录。•专业音频混合器或控制平面•高保真数模转换器•吉他效果踏板超低输入电压噪声100•吉他放大器和其他乐器放大器•专业麦克风和无线系统•耳麦和耳机•振动分析主动Baxandall音调控制10±+±+1101001k10k100k1M10MFrequency(Hz)C020本文档旨在为方便起见，提供有关TI产品中文版本的信息，以确认产品的概要。有关适用的官方英文版本的最新信息，请访问，其内容始终优先。TI不保证翻译的准确性和有效性。在实际设计之前，请务必参考最新版本的英文版本。EnglishDataSheet:SBOS901OPA1656ZHCSJH0A–MARCH2019–REVISEDJULY2019目录1性18ApplicationandImplementation18

2应用18.1ApplicationInformation18

3说明1特8.2TypicalApplications199PowerSupplyRecommendations25

4修订历史记录210Layout25

5PinConfigurationandFunctions36Specifications46.1AbsoluteMaximumRatings46.2ESDRatings41110.1LayoutGuidelines2510.2LayoutExample26器件和文档支持2711.1器件支持276.3RecommendedOperatingConditions411.2文档支持276.4ThermalInformation411.3接收文档更新通知286.5ElectricalCharacteristics511.4社区资源286.6TypicalCharacteristics77DetailedDescription147.1Overview147.2FunctionalBlockDiagram147.3FeatureDescription147.4DeviceFunctionalModes171211.5商标2811.6静电放电警告2811.7Glossary28机和可订购信械、封装息284修订历史记录ChangesfromOriginal(March2019)toRevisionAPage•已更改将器件状态从预告信息（预览）更改为生产数据（正在供货）12Copyright©2019,TexasInstrumentsIncorporatedOPA1656ZHCSJH0A–MARCH2019–REVISEDJULY20195PinConfigurationandFunctionsDPackage

8-PinSOIC

TopViewOUTA18V+±INA27OUTB+INA36±INBV±45+INBNottoscalePinFunctionsPINNAMENO.I/ODESCRIPTIONA2IInvertinginput,channelA+INA3INoninvertinginput,channelAB6IInvertinginput,channelB+INB5INoninvertinginput,channelBOUTA1OOutput,channelAOUTB7OOutput,channelB4—Negative(lowest)powersupplyV+8—Positive(highest)powersupplyCopyright©2019,TexasInstrumentsIncorporated3OPA1656ZHCSJH0A–MARCH2019–REVISEDJULY20196Specifications6.1AbsoluteMaximumRatingsoveroperatingfree-airtemperaturerange(unlessotherwisenoted)(1)MINMAXUNITVoltageSupplyvoltage,VS=(V+)–(V–)40VInput(V–)–0.5(V+)+0.5VCurrentInput(allpinsexceptpower-supplypins)10mAOutputshort-circuit(2)ContinuousOperating,TA125°CTemperatureJunction,TJ150°CStorage,Tstg150°C(1)StressesbeyondthoselistedunderAbsoluteMaximumRatingsmaycausepermanentdamagetothedevice.Thesearestressratings

only,whichdonotimplyfunctionaloperationofthedeviceattheseoranyotherconditionsbeyondthoseindicatedunder

RecommendedOperatingConditions.Exposuretoabsolute-maximum-ratedconditionsforextendedperiodsmayaffectdevicereliability.

(2)Short-circuittoS/2(groundinsymmetricaldual-supplysetups),oneamplifierperpackage.6.2ESDRatingsVALUEUNIT(ESD)ElectrostaticdischargeHuman-bodymodel(HBM),perANSI/ESDA/JEDECJS-001(1)±2000Charged-devicemodel(CDM),perJEDECspecificationJESD22-C101(2)±1000V(1)JEDECdocumentJEP155statesthat500-VHBMallowssafemanufacturingwithastandardESDcontrolprocess.

(2)JEDECdocumentJEP157statesthat250-VCDMallowssafemanufacturingwithastandardESDcontrolprocess.6.3RecommendedOperatingConditionsoveroperatingfree-airtemperaturerange(unlessotherwisenoted)MINNOMMAXUNITSupplyvoltage4.5(±2.25)36(±18)VOperatingtemperature,A125°C6.4ThermalInformationOPA1656THERMALMETRIC(1)D(SOIC)UNIT8PINSJAJunction-to-ambientthermalresistance119.9°C/WJC(top)Junction-to-case(top)thermalresistance51.8°C/WJBJunction-to-boardthermalresistance65.4°C/WJTJunction-to-topcharacterizationparameter10.0°C/WJBJunction-to-boardcharacterizationparameter64.2°C/WJC(bot)Junction-to-case(bottom)thermalresistance–°C/W(1)Formoreinformationabouttraditionalandnewthermalmetrics,seetheSemiconductorandICPackageThermalMetricsapplicationreport.4Copyright©2019,TexasInstrumentsIncorporatedOPA1656ZHCSJH0A–MARCH2019–REVISEDJULY20196.5ElectricalCharacteristicsatTA=25°C,VS=±18V,RL=2kΩ,andVCM=OUT=S/2(unlessotherwisenoted)PARAMETERTESTCONDITIONSMINTYPMAXUNITAUDIOPERFORMANCEG=1,RL=600Ω,VO=3.5RMS,f=1kHz,80-kHzmeasurementbandwidth0.000029%dBTHD+NTotalharmonicdistortion+noiseG=1,R=600Ω,V=3.5V,f=20kHz,LORMS80-kHzmeasurementbandwidthG=1,RL=2Ω,VO=3.5RMS,f=1kHz,80-kHzmeasurementbandwidth0.0001%dB0.000029%dBG=1,RL=2Ω,VO=3.5RMS,f=20kHz,80-kHzmeasurementbandwidth0.000035%dBIMDIntermodulationdistortionG=1O=3.5RMSSMPTE/DINtwo-tone,4:1(60Hzand7kHz)CCIFtwin-tone(19kHzand20kHz)0.000018%dB0.000020%dBFREQUENCYRESPONSEGBWGain-bandwidthproductG=10053MHzUnitygainbandwidthG=120MHzSRSlewrateG=–1,10-Vstep24V/µsFullpowerbandwidth(1)O=1P3.8MHzOverloadrecoverytimeG=–10100nsChannelseparationf=1kHzdBSettlingtime0.01%,G=–1,10-Vstep800nsNOISEInputvoltagenoisef=20Hzto20kHz0.53RMSf=0.1Hzto10Hz1.9PPf=100Hz11.8nV/HznInputvoltagenoisedensityf=1kHz4.3f=10kHz2.9nV/HznInputcurrentnoisedensityf=1kHz6fA/√HzOFFSETVOLTAGEOSInputoffsetvoltageS=±2.25Vto±18V±0.5mVOS/dTInputoffsetvoltagedriftS=±2.25Vto±18VA=–40°Cto+125°C(2)0.32µV/°CPSRRPower-supplyrejectionratioS=±2.25Vto±18V0.35µV/VINPUTBIASCURRENTBInputbiascurrentCM=0V(3)±10±20pAOSInputoffsetcurrentCM=0V±10±20pAINPUTVOLTAGERANGECMCommon-modevoltagerange(V+)–2.25VCMRRCommon-moderejectionratio≤CM≤(V+)–2.25106120dBINPUTIMPEDANCEDifferential100||9.1Ω||pFCommon-mode6||1.912Ω||pFOPEN-LOOPGAINOLOpen-loopvoltagegain+1.3V≤O≤(V+)–1.3VL=600Ω+0.5V≤O≤(V+)–0.5VL=2Ω134150dB134154dB(1)Full-powerbandwidth=SR/π×VP),whereSR=slewrate.(2)Specifiedbydesignandcharacterization.(3)Inputbiascurrenttestconditionscanvaryfromnominalambientconditionsasaresultofjunctiontemperaturedifferences.Copyright©2019,TexasInstrumentsIncorporated5OPA1656ZHCSJH0A–MARCH2019–REVISEDJULY2019ElectricalCharacteristics(continued)atTA=25°C,VS=±18V,RL=2kΩ,andVCM=OUT=S/2(unlessotherwisenoted)PARAMETERTESTCONDITIONSMINTYPMAXUNITOUTPUTOVoltageoutputL=2Ω+0.25(V+)–0.25VOOpen-loopoutputimpedancef=1MHz26ΩSCShort-circuitcurrent(4)±100mALCapacitiveloaddrive100pFPOWERSUPPLYQQuiescentcurrent(perchannel)O=0A,S=±2.25Vto±18V3.94.6mAO=0A,A=–40°Cto+125°C(2)5.0mA(4)Onechannelatatime.6版权©2019,TexasInstrumentsIncorporatedOPA1656ZHCSJH0A–MARCH2019–REVISEDJULY20196.6TypicalCharacteristicsatTA=25°C,VS=±15V,RL=2kΩ,andVCM=S/2(unlessotherwisenoted)1C020Time(1s/div)D029图1.InputVoltageNoiseDensityvsFrequency图2.0.1-Hzto10-HzNoisesrVsrVsrV5(:)D1200D113图3.VoltageNoisevsSourceResistance图4.MaximumOutputVoltagevsFrequency180180GainPhase1501501201206040G=

1G=1G=

10G=+10090902060603030000-30-30100m1101001k10k100k1M10MFrequency(Hz)D104L=10pF-201001k10k100k1M10MFrequency(Hz)L=10pFD106图5.Open-LoopGainandPhasevsFrequency图6.Closed-LoopGainvsFrequency版权©2019,TexasInstrumentsIncorporated7OPA1656ZHCSJH0A–MARCH2019–REVISEDJULY2019TypicalCharacteristics()atTA=25°C,VS=±15V,RL=2kΩ,andVCM=S/2(unlessotherwisenoted)1G=:G=:G=:G=

:G=

:G=

:G=:G=:G=:G=

:G=

:G=

:1)OUT=3RMSBandwidth=80kHzf=1kHzBandwidth=80kHz图7.THD+NRatiovsFrequency图8.THD+NRatiovsOutputAmplitudeG=G=G=G=G=

G=

G=

G=

-100-120-140-160-1800.0050.0030.0020.0010.00070.00050.00030.00020.00017E-55E-5G=1,V=1V(0.354)G=1,V=5V(1.768)G=+1,V=1V(0.354)G=+1,V=5V(1.768)-100-120-200(Hz)3E-52E-5r5r10r18VS(V)OUT=3RMSBandwidth=80kHzf=1kHzL=2kΩBandwidth=80kHz图9.IndividualHarmonicAmplitudevsFrequency图10.THD+NvsSupplyVoltage-600-20-80-40-60-80-100-100-120-120-140-160-180-1401(V)-200201001k10k50kFrequency(Hz)Bandwidth=80kHzG=1,VOUT=3RMSL=2kΩBandwidth=80kHz图11.IntermodulationDistortionvsAmplitude图12.FFT,1-kHzSineWave8版权©2019,TexasInstrumentsIncorporatedOPA1656ZHCSJH0A–MARCH2019–REVISEDJULY2019TypicalCharacteristics()atTA=25°C,VS=±15V,RL=2kΩ,andVCM=S/2(unlessotherwisenoted)00-20-20-40-40-60-60-80-80-100-100-120-120-140-140-160-160-180-180-200-2001k10k80k020k40k60k80kFrequency(Hz)D143Frequency(Hz)D143G=1,VOUT=3RMSL=2kΩBandwidth=80kHzOUT=3RMSL=2kΩBandwidth=80kHz图13.FFT,10-kHzSineWave图14.FFT,CCIFInput(19kHz+20kHz)

01D114D107OUT=3RMSG=1图15.ChannelSeparationvsFrequency图16.CMRRandPSRRvsFrequency(ReferredtoInput)55(qD028(qD027图17.PowerSupplyRejectionRatiovsTemperature(ReferredtoInput)图18.CommonModeRejectionRatiovsTemperature(ReferredtoInput)版权©2019,TexasInstrumentsIncorporated9OPA1656ZHCSJH0A–MARCH2019–REVISEDJULY2019TypicalCharacteristics()atTA=25°C,VS=±15V,RL=2kΩ,andVCM=S/2(unlessotherwisenoted)550012

PD001PqD004Count=7955Count=32图19.InputOffsetVoltageDistribution图20.InputOffsetVoltageDriftDistribution1qC00qCqCqC5-9-6-30369qD017D0195typicalunitsshown图21.InputOffsetvsTemperature图22.InputOffsetvsCommonModeVoltageINOUTINOUTPPD137D135G=1L=20pFG=–1L=100pF图23.Small-SignalStepResponse(100mV)图24.Small-SignalStepResponse(100mV)10版权©2019,TexasInstrumentsIncorporatedOPA1656ZHCSJH0A–MARCH2019–REVISEDJULY2019TypicalCharacteristics()atTA=25°C,VS=±15V,RL=2kΩ,andVCM=S/2(unlessotherwisenoted)INOUTINOUTPPD136G=1L=2kΩL=100pFG=–1L=100pFD139图25.Large-SignalStepResponse图26.Large-SignalStepResponse521IB+IB-IOS55qD033(qD024图27.Open-LoopGainvsTemperature图28.BandOSvsTemperature4B-IIS=VS=V00369D0235(qD031图29.BandOSvsCommon-ModeVoltage图30.SupplyCurrentvsTemperature版权©2019,TexasInstrumentsIncorporated11OPA1656ZHCSJH0A–MARCH2019–REVISEDJULY2019TypicalCharacteristics()atTA=25°C,VS=±15V,RL=2kΩ,andVCM=S/2(unlessotherwisenoted)4qCqC3qC2qC0480D030D025图31.SupplyCurrentvsSupplyVoltage图32.OutputVoltagevsOutputCurrent(Sourcing)qCqCqCqC05D026(qD041图33.OutputVoltagevsOutputCurrent(Sinking)图34.Short-CircuitCurrentvsTemperatureISO=0:ISO=:ISO=:0LD105CLD037G=1G=1图35.PhaseMarginvsCapacitiveLoad图36.PercentOvershootvsCapacitiveLoad12版权©2019,TexasInstrumentsIncorporatedOPA1656ZHCSJH0A–MARCH2019–REVISEDJULY2019TypicalCharacteristics()atTA=25°C,VS=±15V,RL=2kΩ,andVCM=S/2(unlessotherwisenoted)ISO=0:ISO=:ISO=:0CLD131G=–1G=–10INOUTD134图37.PercentOvershootvsCapacitiveLoad图38.NegativeOverloadRecoveryINOUT1G=–10D1381D112图39.PositiveOverloadRecovery图40.Open-LoopOutputImpedancevsFrequencyINOUTD138G=1图41.NoPhaseReversal版权©2019,TexasInstrumentsIncorporated13OPA1656ZHCSJH0A–MARCH2019–REVISEDJULY20197DetailedDescription7.1OverviewTheOPA1656usesathree-gain-stagearchitecturetoachieveverylownoiseanddistortion.TheFunctional

BlockDiagramshowsasimplifiedschematicoftheOPA1656(onechannelshown).Thedeviceconsistsofalow

noiseinputstageandfeedforwardpathwaycoupledtoahigh-currentoutputstage.Thistopologyexhibits

superiordistortionperformanceunderawiderangeofloadingconditionscomparedtootheroperational

amplifiers.7.2FunctionalBlockDiagramFeed-

forward

PathCC+INInputStageGainStageOutputStageOUT-IN7.3FeatureDescription7.3.1PhaseReversalProtectionTheOPA1656hasinternalphase-reversalprotection.Manyopampsexhibitphasereversalwhentheinputis

drivenbeyondthelinearcommon-moderange.Thisconditionismostoftenencounteredinnoninvertingcircuits

whentheinputisdrivenbeyondthespecifiedcommon-modevoltagerange,causingtheoutputtoreverseinto

theoppositerail.TheinputoftheOPA1656preventsphasereversalwithexcessivecommon-modevoltage.

Instead,theappropriateraillimitstheoutputvoltage.Thisperformanceisshownin图42.50-10-15-20Times/div)VINVOUT图42.OutputWaveformDevoidofPhaseReversalDuringanInputOverdriveCondition7.3.2ElectricalOverstressDesignersoftenaskquestionsaboutthecapabilityofanoperationalamplifiertowithstandelectricaloverstress.

Thesequestionstendtofocusonthedeviceinputs,butcaninvolvethesupplyvoltagepinsoreventheoutput

pin.Eachofthesedifferentpinfunctionshaveelectricalstresslimitsdeterminedbythevoltagebreakdown

characteristicsoftheparticularsemiconductorfabricationprocessandspecificcircuitsconnectedtothepin.

Additionally,internalelectrostaticdischarge(ESD)protectionisbuiltintothesecircuitstoprotectthemfrom

accidentalESDeventsbothbeforeandduringproductassembly.14版权©2019,TexasInstrumentsIncorporatedOPA1656ZHCSJH0A–MARCH2019–REVISEDJULY2019FeatureDescription()AgoodunderstandingofthisbasicESDcircuitryandtherelevancetoanelectricaloverstresseventishelpful.图

43illustratestheESDcircuitscontainedintheOPA1656(indicatedbythedashedlinearea).TheESD

protectioncircuitryinvolvesseveralcurrent-steeringdiodesconnectedfromtheinputandoutputpinsandrouted

backtotheinternalpower-supplylines,wherethediodesmeetatanabsorptiondeviceinternaltotheoperational

amplifier.Thisprotectioncircuitryisintendedtoremaininactiveduringnormalcircuitoperation.TVSRF+VSR1IN±20ŸRSIN+20Ÿ+Power-SupplyESDCellRL+VIN±±VSTVS图43.EquivalentInternalESDCircuitryRelativetoaTypicalCircuitApplicationAnESDeventproducesashort-duration,high-voltagepulsethatistransformedintoashort-duration,high-

currentpulsewhendischargingthroughasemiconductordevice.TheESDprotectioncircuitsaredesignedto

provideacurrentpatharoundtheoperationalamplifiercoretopreventdamage.Theenergyabsorbedbythe

protectioncircuitryisthendissipatedasheat.WhenanESDvoltagedevelopsacrosstwoormoreamplifierdevicepins,currentflowsthroughoneormore

steeringdiodes.Dependingonthepaththatthecurrenttakes,theabsorptiondevicecanactivate.Theabsorption

devicehasatrigger,orthresholdvoltage,thatisabovethenormaloperatingvoltageoftheOPA1656butbelow

thedevicebreakdownvoltagelevel.Whenthisthresholdisexceeded,theabsorptiondevicequicklyactivates

andclampsthevoltageacrossthesupplyrailstoasafelevel.Whentheoperationalamplifierconnectsintoacircuit,asshownin图43,theESDprotectioncomponentsare

intendedtoremaininactiveanddonotbecomeinvolvedintheapplicationcircuitoperation.However,

circumstancesmayarisewhereanappliedvoltageexceedstheoperatingvoltagerangeofagivenpin.Ifthis

conditionoccurs,thereisariskthatsomeinternalESDprotectioncircuitscanturnonandconductcurrent.Any

suchcurrentflowoccursthroughsteering-diodepathsandrarelyinvolvestheabsorptiondevice.图43showsaspecificexamplewheretheinputvoltage(VIN)exceedsthepositivesupplyvoltage(V+)by500

mVormore.Muchofwhathappensinthecircuitdependsonthesupplycharacteristics.IfV+cansinkthe

current,oneoftheupperinputsteeringdiodesconductsanddirectscurrenttoV+.ExcessivelyhighcurrentlevelscanflowwithincreasinglyhigherIN.Asaresult,thedatasheetspecificationsrecommendthat

applicationslimittheinputcurrentto10mA.版权©2019,TexasInstrumentsIncorporated15OPA1656ZHCSJH0A–MARCH2019–REVISEDJULY2019FeatureDescription()Ifthesupplyisnotcapableofsinkingthecurrent,VINcanbeginsourcingcurrenttotheoperationalamplifierand

thentakeoverasthesourceofpositivesupplyvoltage.Thedangerinthiscaseisthatthevoltagecanriseto

levelsthatexceedtheoperationalamplifierabsolutemaximumratings.Anothercommonquestioninvolveswhathappenstotheamplifierifaninputsignalisappliedtotheinputwhen

thepowersupplies(V+orV–)areat0V.Again,thisquestiondependsonthesupplycharacteristicwhenat0V,

oratalevelbelowtheinputsignalamplitude.Ifthesuppliesappearashighimpedance,thentheinputsource

suppliestheoperationalamplifiercurrentthroughthecurrent-steeringdiodes.Thisstateisnotanormalbias

condition;mostlikely,theamplifierdoesnotoperatenormally.Ifthesuppliesarelowimpedance,thenthecurrent

throughthesteeringdiodescanbecomequitehigh.Thecurrentleveldependsontheabilityoftheinputsource

todelivercurrent,andanyresistanceintheinputpath.Ifthereisanyuncertaintyabouttheabilityofthesupplytoabsorbthiscurrent,addexternalZenerdiodestothe

supplypins;see图43.SelecttheZenervoltagesothatthediodedoesnotturnonduringnormaloperation.

However,theZenervoltagemustbelowenoughsothattheZenerdiodeconductsifthesupplypinbeginstorise

abovethesafe-operating,supply-voltagelevel.7.3.3EMIRejectionRatio(EMIRR)Theelectromagneticinterference(EMI)rejectionratio,orEMIRR,describestheEMIimmunityofoperational

amplifiers.Anadverseeffectthatiscommontomanyoperationalamplifiersisachangeintheoffsetvoltageasa

resultofRFsignalrectification.Anoperationalamplifierthatismoreefficientatrejectingthischangeinoffsetas

aresultofEMIhasahigherEMIRRandisquantifiedbyadecibelvalue.MeasuringEMIRRcanbeperformedin

manyways,butthisdocumentprovidestheEMIRRIN+,whichspecificallydescribestheEMIRRperformance

whentheRFsignalisappliedtothenoninvertinginputpinoftheoperationalamplifier.Ingeneral,onlythe

noninvertinginputistestedforEMIRRforthefollowingthreereasons:•OperationalamplifierinputpinsareknowntobethemostsensitivetoEMI,andtypicallyrectifyRFsignals

betterthanthesupplyoroutputpins.•Thenoninvertingandinvertingoperationalamplifierinputshavesymmetricalphysicallayoutsandexhibit

nearlymatchingEMIRRperformance.•EMIRRiseasiertomeasureonnoninvertingpinsthanonotherpinsbecausethenoninvertinginputpincan

beisolatedonaprinted-circuit-board(PCB).ThisisolationallowstheRFsignaltobeapplieddirectlytothe

noninvertinginputpinwithnocomplexinteractionsfromothercomponentsorconnectingPCBtraces.AmoreformaldiscussionoftheEMIRRIN+definitionandtestmethodisprovidedintheEMIRejectionRatioof

OperationalAmplifiersapplicationreport,availablefordownloadat.TheEMIRRIN+oftheOPA1656isplottedversusfrequencyin图44.Ifavailable,anydualandquadoperational

amplifierdeviceversionshavenearlyidenticalEMIRRIN+performance.TheOPA1656unity-gainbandwidthis

20MHz.EMIRRperformancebelowthisfrequencydenotesinterferingsignalsthatfallwithintheoperational

amplifierbandwidth.1401201008060402010M100M1G10GFrequency(Hz)D115图44.OPA1656EMIRRvsFrequency16版权©2019,TexasInstrumentsIncorporatedOPA1656ZHCSJH0A–MARCH2019–REVISEDJULY2019FeatureDescription()表1liststheEMIRRIN+valuesfortheOPA1656atparticularfrequenciescommonlyencounteredinreal-world

applications.Applicationslistedin表1canbecenteredonoroperatedneartheparticularfrequencyshown.This

informationcanbeofspecialinteresttodesignersworkingwiththesetypesofapplications,orworkinginother

fieldslikelytoencounterRFinterferencefrombroadsources,suchastheindustrial,scientific,andmedical(ISM)

radioband.表1.OPA1656EMIRRIN+forFrequenciesofInterestFREQUENCYAPPLICATIONORALLOCATIONEMIRRIN+400MHzMobileradio,mobilesatellite,spaceoperation,weather,radar,UHF36dB900MHzGSM,radiocommunicationandnavigation,GPS(to1.6GHz),ISM,

aeronauticalmobile,UHF42dB1.8GHzGSM,mobilepersonalcomm.broadband,satellite,L-band52dB2.4GHz802.11b/g/n,Bluetooth™,mobilepersonalcomm.,ISM,amateurradioandsatellite,S-band64dB3.6GHzRadiolocation,aerocomm./nav.,satellite,mobile,S-band67dB5GHz802.11a/n,aerocommunicationandnavigation,mobilecommunication,

spaceandsatelliteoperation,C-band77dBEMIRRIN+TestConfiguration图45showsthecircuitconfigurationfortestingtheEMIRRIN+.AnRFsourceisconnectedtotheoperational

amplifiernoninvertinginputpinusingatransmissionline.Theoperationalamplifierisconfiguredinaunity-gain

buffertopologywiththeoutputconnectedtoalow-passfilter(LPF)andadigitalmultimeter(DMM).Alarge

impedancemismatchattheoperationalamplifierinputcausesavoltagereflection;however,thiseffectis

characterizedandaccountedforwhendeterminingtheEMIRRIN+.Theresultingdcoffsetvoltageissampled

andmeasuredbythemultimeter.TheLPFisolatesthemultimeterfromresidualRFsignalsthatcaninterferewith

multimeteraccuracy.SeetheEMIRejectionRatioofOperationalAmplifiersapplicationreportformoredetails.Ambienttemperature:25Û&+VS±50Low-PassFilter+RFsourceDCBias:0VModulation:None(CW)FrequencySweep:201pt.Log-VSNotshown:0.1µFand10µFsupplydecouplingSample/AveragingDigitalMultimeter图45.EMIRRIN+TestConfigurationSchematic7.4DeviceFunctionalModes7.4.1OperatingVoltageTheOPA1656operatesfrom±2.25Vto±18Vsupplieswhilemaintainingexcellentperformance.TheOPA1656

canoperatewithaslittleas4.5Vbetweenthesuppliesandwithupto36Vbetweenthesupplies.However,

someapplicationsdonotrequireequalpositiveandnegativeoutputvoltageswing.WiththeOPA1656,power-

supplyvoltagesarenotrequiredtobeequal.Forexample,thepositivesupplycanbesetto25Vwiththe

negativesupplyat–5V.Inallcases,thecommon-modevoltagemustbemaintainedwithinthespecifiedrange.Inaddition,key

parametersarespecifiedoverthetemperaturerangeofTA=–40°Cto125°C.版权©2019,TexasInstrumentsIncorporated17OPA1656ZHCSJH0A–MARCH2019–REVISEDJULY20198ApplicationandImplementation注InformationinthefollowingapplicationssectionsisnotpartoftheTIcomponent

specification,andTIdoesnotwarrantitsaccuracyorcompleteness.TI’scustomersare

responsiblefordeterminingsuitabilityofcomponentsfortheirpurposes.Customersshould

validateandtesttheirdesignimplementationtoconfirmsystemfunctionality.8.1ApplicationInformation8.1.1BasicNoiseCalculationsLow-noisecircuitdesignrequirescarefulanalysisofallnoisesources.Externalnoisesourcescandominatein

manycases;considertheeffectofsourceresistanceonoverallopampnoiseperformance.Totalnoiseofthe

circuitistheroot-sum-squarecombinationofallnoisecomponents.图46showsnoninverting(A)andinverting(B)opampcircuitconfigurationswithgain.Incircuitconfigurations

withgain,thefeedbacknetworkresistorscontributenoise.Ingeneral,thecurrentnoiseoftheopampreactswith

thefeedbackresistorstocreateadditionalnoisecomponents.Theselectedfeedbackresistorvaluesmakethesenoisesourcesnegligible.Lowimpedancefeedbackresistors

loadtheoutputoftheamplifier.Theequationsfortotalnoiseareshownforbothconfigurations.(A)NoiseinNoninvertingGainConfigurationNoiseattheoutputisgivenasEO,whereRR12GND±+EO44„421222+:E:1;'=l1+1p„:A;+:A;+kAo„4;+lE„dhp¨222504æ40501244+4112:2;5=¥4„G$„6(-)„5d8¾*VhThermalnoiseofRS>4/5?RS1„28:3;41æ2=¨4„G$„6(-)„dhdh1+2¾*VThermalnoiseofR1||R2+±VSSource,:4;G$=1.38065„1023dh-:5;6(-)=237.15+6(°%)>-?BoltzmannConstantTemperatureinkelvinsGND(B)NoiseinInvertingGainConfigurationNoiseattheoutputisgivenasEO,whereRSR1R2±242:5+1;„422+FEIG:6;1=l1+p„¨:0;2+k41+45æ42o0„H5+15+1+42>4/5?+EO:5+1;„428:7;4145æ42=¨4„G$„6(-)„HIdh5+1+42¾*VThermalnoiseof(R1+RS)||R2

+VS±SourceGND:8;G$=1.38065„10F23d,h-BoltzmannConstantGND:9;6(-)=237.15+6(°%)>-?TemperatureinkelvinsCopyright©2017,TexasInstrumentsIncorporated(1)Nisthevoltagenoiseoftheamplifier.FortheOPA1656,eN=4.3nV/Hzat1kHz.(2)Nisthecurrentnoiseoftheamplifier.FortheOPA1656,iN=6fA/Hzat1kHz.(3)Foradditionalresourcesonnoisecalculations,seePrecisionLabsSeries.图46.NoiseCalculationinGainConfigurations18版权©2019,TexasInstrumentsIncorporatedOPA1656ZHCSJH0A–MARCH2019–REVISEDJULY20198.2TypicalApplications8.2.1PreamplifierCircuitforVinylRecordPlaybackWithMoving-MagnetPhonoCartridgesThenoiseanddistortionperformanceoftheOPA1656isexceptionalinapplicationswithhighsource

impedances,whichmakesthesedevicesanexcellentchoiceinpreamplifiercircuitsformovingmagnetphono

cartridges.Thehighsourceimpedanceofthecartridge,andhighgainrequiredbytheRIAAplaybackcurveat

lowfrequency,requiresanamplifierwithbothlowinputcurrentnoiseandlowinputvoltagenoise.15VMMPhonoInputR147kC1150pFV+V±R2118k+±-15VOPA1656VOUTR310kR5100C5100uFR6100kOutputR4127C227nFC37.5nFC4100FCopyright©2018,TexasInstrumentsIncorporated图47.PreamplifierCircuitforVinylRecordPlaybackWithMoving-MagnetPhonoCartridges(SingleChannelShown)DesignRequirements•Gain:40dB(1kHz)•RIAAAccuracy:±0.5dB(100Hzto20kHz)

•PowerSupplies:±15V版权©2019,TexasInstrumentsIncorporated19OPA1656ZHCSJH0A–MARCH2019–REVISEDJULY2019TypicalApplications()DetailedDesignProcedureVinylrecordsarerecordedusinganequalizationcurvespecifiedbytheRecordingInstituteAssociationof

America(RIAA)