集成电路专业英语 课件汇 1 Introduction to Semiconductor - 7 Analog Integrated Circuits

1IntroductiontoSemiconductorPartIIntegratedCircuitFundamentals-

SemiconductorPhysics

IntroductiontoSemiconductorsPrimarymaterialsforIntegratedCircuits(ICs)anddevicesliketransistorsanddiodesEnableinformationprocessing,speed,efficiency,andpowercontrolAdvancedmaterialsincludeGaNandSiCforcutting-edgeapplicationsDefinition&ElectricalResistivitySemiconductorshaveelectricalpropertiesbetweeninsulatorsandconductorsResistivityrange:10^-4to10^8Ω-cm(e.g.,Silicon,Germanium)CriticalforcontrolledelectronflowinelectronicsClassificationofSemiconductorsElementalsemiconductorsfromGroupIVelementsCompoundsemiconductorsfromcombinationslikeGroupIII-VIntrinsic(pure)vsExtrinsic(doped)materialsElementalvs.CompoundMaterialsElemental:Silicon(Si)andGermanium(Ge)Compound:GaAs,GaPwithsuperioropticalandspeedpropertiesUsedinhigh-speedandoptoelectronicapplicationsAtomicStructureofSiliconSiliconhas4valenceelectronsformingcovalentbondsCreatesastablecrystallatticestructureAt0K,siliconbehavesasaperfectinsulatorThermalGeneration&CarrierMovementThermalenergybreakscovalentbondsatroomtemperatureGeneratesfreeelectronsandholesConductivityincreaseswithtemperatureIntrinsicCarrierConcentrationInintrinsicsilicon:n=p=ninidependsontemperatureandbandgapenergyForSiatroomtemperature:~1.5×10^10cm^-3IntroductiontoDopingIntrinsicsiliconhaslowandtemperature-sensitiveconductivityDopingintroducesimpuritiestocontrolconductivityDonorscreateN-type;AcceptorscreateP-typeExtrinsicSemiconductor:N-TypeDopedwithpentavalentelementslikePhosphorusExtraelectronbecomesfreeandincreasesconductivityElectronsaremajoritycarriersExtrinsicSemiconductor:P-TypeDopedwithtrivalentelementslikeBoronCreatesholesasmajoritycarriersKnownasP-type(positivetype)materialKeyTerminologyIntegratedCircuit:multiplecomponentsononechipBandgapEnergy:energytobreakcovalentbondsRecombination:electron-holeannihilationReview&ExercisesSemiconductorsbalanceconductivitybetweeninsulatorsandconductorsDopingcreatesN-typeandP-typematerialsExercises:resistivityrangeandintrinsicvsextrinsic2EnergyBandsandChargeCarriersinSemiconductorIntroductionElectricalconductivitycanbepreciselymanipulatedControlledbydoping,electricfields,andlightHighlysensitivetotemperatureandexternalstimuliTheFormationofEnergyBandsIsolatedatomshavediscreteenergylevelsInsolids,atomicorbitalsoverlapandformenergybandsInnerorbitelectronsremainlargelyunaffectedKeyEnergyBandClassificationsValenceband:highestoccupiedenergybandConductionband:freeelectronsresponsibleforcurrentForbiddengapseparatesvalenceandconductionbandsMaterialClassificationbyBandGapInsulatorshavelargebandgapspreventingconductionSemiconductorshavesmallgaps(Si:1.1eV,Ge:0.72eV)ConductorshaveoverlappingbandsChargeCarrierDynamics:DriftCurrentDriftiscausedbyanappliedelectricfieldElectronsmoveoppositetothefield;holesmovewithitElectronmobilityis~2.5xholemobilityinsiliconMathematicsofDriftandResistivityDriftvelocityproportionaltoelectricfieldandmobilityCurrentdensitydependsoncarrierconcentrationandmobilityResistivityinverselyrelatedtocarriertransportChargeCarrierDynamics:DiffusionCurrentDiffusiondrivenbynon-uniformcarrierconcentrationCarriersmovefromhightolowconcentrationDiffusionconstantsdifferforelectronsandholesTheEinsteinRelationshipLinksdiffusionconstantandmobilityDefinedbythermalvoltageVT=kT/qAt300K,VT≈25.9mVSummaryofKeyTermsValenceelectronsoccupytheouteratomicshellHolesactaspositivechargecarriersBandgapdeterminesconductioncapability3DiodePartIIIntegratedCircuitFundamentals-SemiconductorDevicesIntroductiontoDiodesFundamentalsemiconductordevicesbasedonthePNjunctionFormedbyjoiningP-typeandN-typeregionsonasinglesubstrateProvideunidirectionalcurrentflowformanyapplicationsPNJunctionFormationP-typehashighholeconcentration;N-typehashighelectronconcentrationDiffusionandrecombinationoccurattheinterfaceIonizedatomsformthespacecharge(depletion)regionInternalElectricField&EquilibriumInternalelectricfieldformsfromN-regiontoP-regionDiffusionanddriftcurrentsopposeeachotherEquilibriumresultsinzeronetcurrentwithoutbiasBiasingConditions:Zero&ReverseBiasZerobias:noexternalvoltage,barrierpreventscurrentflowReversebiaswidensthedepletionregionOnlyaverysmallleakagecurrentflowsBiasingConditions:ForwardBiasForwardbiasreducesdepletionwidthAllowslargecurrentflowwithlowresistanceBarriervoltage:~0.7V(Si),~0.3V(Ge)IVCharacteristicsofaDiodeNon-linear,exponentialcurrent-voltagerelationshipKneepointmarksrapidcurrentincreaseHighreversevoltagecausesavalanchebreakdownSpecialDiodes:ZenerDiodesOperateinreversebreakdownatafixedZenervoltageHeavilydopedtocontrolbreakdownpreciselyWidelyusedforvoltageregulationSpecialDiodes:SchottkyDiodesFormedbyametal–semiconductorjunctionVeryfastswitchingandlowforwardvoltagedropUsedinhigh-speedandRFapplicationsOptoelectronics:LEDs&SolarCellsLEDsemitlightthroughelectroluminescenceSolarcellsconvertlightintoelectricalenergyKeyparametersincludeIscandVocSummaryofKeyTermsSubstrate:basematerialfordevicefabricationSpacechargeregion:depletionlayeratthejunctionMajoritycarriers:holesinP-type,electronsinN-type4BipolarJunctionTransistors(BJTs)IntroductiontoBipolarJunctionTransistors(BJTs)TransistorsaretheprimarybuildingblocksofmodernelectroniccircuitsBJTswerethefirsttransistorsdevelopedandarestillwidelyusedUsedforsignalamplificationandswitching;current-controlleddevicesBJTStructureandTypesThreeterminals:Base(B),Collector(C),andEmitter(E)Constructedfromthreedopedregionsformingtwop–njunctionsTwotypes:npnandpnptransistorsBasicOperationPrinciplesBase–EmittercurrentcontrolsCollectorcurrentCollectorandEmitterarenotinterchangeableduetoasymmetryOperationinvolvesbothmajorityandminoritycarriersBJTvs.MOSFET(FET)BJTiscurrent-controlled;MOSFETisvoltage-controlledBJTisbipolar;MOSFETisunipolarBJTsamplifycurrent;MOSFETscontrolcurrentviavoltageCircuitConfigurationsandVoltagesThreeconfigurations:Common-Base,Common-Emitter,Common-CollectorSupplyvoltages:VCCandVBBTerminalandjunctionvoltagesdefineoperationOperatingRegimesSaturation:maximumcollectorcurrent,bothjunctionsforwardbiasedCutoff:nobase-emitterconduction,zerocurrentUsedasON/OFFswitchindigitalapplicationsTechnicalGlossaryBipolarJunctionTransistor(BJT):双极结型晶体管FieldEffectTransistor(FET):场效应晶体管Common-Emitter,Saturation,Cutoff:keyoperatingterms5Field-EffectTransistors(FETs)IntroductiontoFETsVoltage-controlledunipolardevicesusingmajoritycarriersControlledbyanelectricfieldratherthaninputcurrentHighinputimpedance,lowpower,idealforICsJunctionFET(JFET)StructureThreeterminals:Gate,Drain,andSourceConstructedfromathinsemiconductorbar(SiorGaAs)N-channelandP-channeltypesKeyCharacteristicsofJFETsVeryhighinputimpedanceandlownoiseCurrentcarriedonlybymajoritycarriersTemperature-dependentcharacteristicsJFETOutputCharacteristicsIdvsVdsatconstantVgsOhmic,Saturation,Pinch-off,andBreakdownregionsDraincurrentcontrolledbygatevoltageJFETTransferCharacteristicsRelationshipbetweenIdandVgsatfixedVdsIddecreasesasVgsbecomesmorenegative(N-channel)DefinestransconductanceMOSFETStructure&OperationInsulated-gateFETwithoxidelayerExtremelyhighinputimpedanceChannelformswhenVGSexceedsthresholdvoltageMOSFETModesandScalingEnhancementanddepletionmodesExcellentscalabilityforVLSIDominantdeviceinCPUsandmemoryComplementaryMOS(CMOS)TechnologyUsesbothNMOSandPMOSdevicesVerylowstaticpowerconsumptionGlobalstandardforintegratedcircuitsSummaryofKeyTermsThresholdvoltagedefineschannelformationTransfercharacteristicsdescribegatecontrolGaAsusedasalternativeJFETmaterial6SpecialSemiconductorDevicesIntroductiontoSpecialSemiconductorsDesignedforhigh-stakesrequirementsbeyondbasicdevicesEnablepowercontrolandphotonicapplicationsEssentialtopowerelectronicsandoptoelectronicsThyristors–GateTurn-Off(GTO)Threeterminals:Anode,Cathode,andGateCanbeturnedONandOFFusinggatecontrolUsedininverters,choppers,andtractionsystemsTRIACs(TriodeACSwitch)BidirectionalconductionforACpowercontrolEquivalenttotwoSCRsinantiparallelTurnedoffwhencurrentcrosseszeroDIACs(DiodeforAlternatingCurrent)BidirectionaldiodewithoutagateterminalConductsafterreachingbreakovervoltageCommonlyusedtotriggerTRIACsPhotonicDevices–PhotodiodesConvertincidentlightintophotocurrentOftenusePINjunctionforbetterperformanceBandwidthaffectedbyjunctioncapacitanceSolarCells(PhotovoltaicEnergy)ConvertsunlightintoelectricalenergyBasedonp–njunctioncarrierseparationFuturetrendsincludeadvancedsiliconstructuresPowerDiodesDesignedforhighvoltageandcurrenthandlingUseP+–N−junctionstructuresUsedinrectifiersandprotectioncircuitsPowerTransistorsHigh-powerBJTscontrollargecurrentsSmallbasecurrentcontrolslargecollectorcurrentUsedinSMPS,converters,andinvertersTechnicalSummaryGTO:gate-controlledpowerswitchingTRIAC&DIAC:ACpowercontrolandtriggeringPhotodiodes&SolarCells:optoelectronicenergyconversion7AnalogIntegratedCircuitsPartIIIIntegratedCircuitDesignWhyAnalogICsMatterNotallfunctionscanberealizeddigitallyFront-endsignalconditioningisalwaysanalogHigh-speeddigitalsystemsrelyonanalogprinciplesAnalogvsDigitalProcessingAnalog:continuous-time,sensitivetonoiseanddistortionDigital:discretelevels(0/1),toleranttonoiseModernsystemscombinebothdomainsOperationalAmplifiers(Op-Amps)High-gainmulti-stageamplifiersDifferentialinput,single-endedoutputCorebuildingblockofanalogICdesignOp-AmpSymbolandTerminalsInverting(−)inputNon-inverting(+)inputOutputterminalPositiveandnegativesupplyrailsSimplifiedOp-AmpModelModeledasavoltage-controlledvoltagesourceVeryhighinputresistanceLowoutputresistanceLargeopen-loopgainOp-AmpKeyParametersInputoffsetvoltageInputbiascurrentOpen-loopgainOutputvoltageswingPARAMETERTESTCONDITIONSLF411ALF411UNITMINTYPMAXMINTYPMAXVOSInputOffsetVoltageRS=10kΩ,TA=25℃

0.30.5

0.82.0mVΔVOS/ΔTAverageTCofInputOffsetVoltageRS=10kΩ

7

7

μV/℃IOSInputOffsetCurrentVS=±15V(2)(3)Tj=25℃

25100

25100pATj=70℃

2

2nATj=125℃

25

25nAIBInputBiasCurrentVS=±15V(2)(3)Tj=25℃

50200

50200pATj=70℃

4

4nATj=125℃

50

50nARINInputResistanceTj=25℃

1012

1012

ΩAVOLLargeSignalVoltageGainVS=±15V,VO=±10V,RL=2k,TA=25℃50200

25200

V/mVOverTemperature25200

15200

V/mVVOOutputVoltageSwingVS=±15V,RL=2k±12±13.5

±12±13.5

VVCMInputCommon-ModeVoltageRange

±16+19.5

±11+14.5

V

-16.5

-11.5

VCMRRCommon-ModeRejectionRatioRS≤10k80100

70100

dBPSRRSupplyVoltageRejectionRatioSee(4)80100

70100

dBISSupplyCurrent

1.82.8

1.83.4mAOp-AmpACCharacteristicsSlewrateGain-bandwidthproduct(GBW)InputnoisevoltageandcurrentTotalharmonicdistortion(THD)PARAMETER(1)(2)TESTCONDITIONSLF411ALF411UNITMINTYPMAXMINTYPMAXSRSlewRateVS=±15V,TA=25℃1015

815

V/μsGBWGain-BandwidthProductVS=±15V,TA=25℃34

2.74

MHzenEquivalentInputNoiseVoltageTA=25℃,RS=100Ω,f=1kHz

25

25

nV/√HzinEquivalentInputNoiseCurrentTA=25℃,f=1kHz

0.01

0.01

pA/√HzTHDTotalHarmonicDistortionAV=+10,RL=10k,VO=20Vp-p,BW=20Hz-20kHz

<0.02%

<0.02%

VoltageReferencesProvidestable,accuratevoltagesCriticalforADCandDACaccuracyAccuracydirectlylimitssystemresolutionTypesofVoltageReferencesSeries(three-terminal)referencesShunt(two-terminal)referencesTrade-offsinaccuracy,current,andflexibilityDiode-BasedReferencesForward-biaseddiodereferencesZener/avalanchediodereferencesSimplebutlimitedaccuracyandnoiseperformanceBandgapVoltageReferencesBasedonsiliconbandgap(~1.205V)ExcellenttemperaturestabilityOperatesatlowsupplyvoltagesBrokawBandgapCellUsesΔVBEandVBEsummationTemperaturecoefficientminimizedFoundationofmodernprecisionreferencesAnalogFiltersFrequency-selectivesignalprocessingSuppressinterferenceandnoiseEssentialincommun