ESD EMI介绍与分析

IntegratedSolutionsESDTypesESD类型-DirectESDstress直接ESD应力•Generatedbycontactdischarge,upto8kVinIEC61000-4-2standard接触放电产生，IEC61000-4-2标准中最高为8kV•Generatedbyairdischarge,upto15kVinIEC61000-4-2standard空气放电产生，IEC61000-4-2标准中最高为15kV-IndirectESDstress间接ESD应力•ESDconditionsarecharacterizedbyfastrisetime(nsecs).ESD状况的特点是快速上升时间(nsecs)。•PCBlayersinducesparasiticcapacitancethentheC*dV/dteffectinducesaparasiticcurrent.PCB布局产生寄生电容，然后C*dV/dt的影响产生寄生电流。MostIC’sarenotprotectedforESDconditionshigherthan2kV大多数IC不能保护高于2kV的ESD状况。IEC61000IEC61000--44--2standard2standardIntegratedSolutionsESDWaveform:IEC61000-4-2Time(ns)Current(A)Risetime=0.7to1.0ns100%SeverityLevelDischarge放电Initial初始30ns60ns强度Voltage电压Current电流CurrentCurrent12kV7.5A4A2A24kV15.0A8A4A36kV22.5A12A6A48kV30.0A16A8A30ns60nsIntegratedSolutionsESDTestMethods,cont’dESDSurgeGeneratorESDDischargeWaveform3)IEC61000-4-2:EuropeanstandardIntegratedSolutions各种器件对静电的敏感程度SusceptibilityofElectronicComponentstoESDDeviceTechnologyESDSusceptibilityVMOS30-1,200VMOSFET,GaAsFet,EPROM100-300VJFET150-7000VOp-Amp190-2,500VSchottkyDiodes300-2,500VFilmResistors300-3,000VSchottkyTTL1,000-3,000VIntegratedSolutionsCatastrophicESDFailureModes静电损坏种类JunctionBurnout(半导体)结烧坏OxidePunch-through氧化硅击穿MetallizationBurnout电导线熔断AlloySpikeJunctionShortECBAlSiO2SiOxideShortAlSiO2SiTransistorsDielectricsInterconnectsIntegratedSolutionsMultiLayerVaristor-MLV多层压敏变阻器FiredCeramic(ZnO)陶瓷(氧化锌)MetalInnerElectrodes金属栅极EndTermination端头Intergranular颗粒间Boundary边界(R=109Ω,variable变量)ZnOGrain颗粒(R=1-10Ω)IntegratedSolutionsIR@5VDegradationWhenAppliedRepetitiveSurge8x20usec,ONSemivsVaristors施加8x20usec的重复浪涌时，安森美半导体和变阻器IR@5V的衰变Ipp=10A(Surge8x20usec)Ipp=10A(浪涌8x20usec)IR@5VDegrationvsNumberofPulsesIR@5V衰变和脉冲数量的关系0.010.111002004006008001000PulseIR@5V,uAONSemi‘sSMF05C安森美半导体SMF05CVaristor变阻器IntegratedSolutionsEMITypesandGeneration1.-ConductedEMIisnoisefedbackfromasystemontotheACorDCpowerlineorsignallines.Itusuallyhasacommonmodecomponentandadifferentialmodecomponent.Thecommonmodecomponentappearsasavoltageonbothlineandneutralleadswithrespecttogroundorearthwhilethedifferentialmodeappearsbetweenthelineandneutralleads.TosuppressconductedEMI,LCnetworksareusuallyused.2.-RadiatedEMIcomesintheformofelectromagneticwavesradiatingdirectlyfromthecircuitryandleadsofasystem.AcommonexampleistheACpowercordofthesystemwhichcanactasatransmittingantennaforradiatedEMI.Rangingfrom30MHzto1GHz,thistypeofnoisecanbeeffectivelysuppressedbymetalshieldingaroundthesource.ConductedEMI,acpowerline60HzRadiatedEMI,highfrequencyclockIntegratedSolutionsHowEMIfilterfunctionsIntegratedSolutionsHowEMIfilterfunctions(cont)IntegratedSolutionsEMIfilteringforPortableElectronicsLCDDiskDriveSIM/MMcardKeypadTouchpadRS232ConnectorUSBFirewireMicroPhoneHeadsetSpeakerCameraDigitalCameraWirelessHandsetGPSPDAMP3IntegratedSolutionsPerformancecomparisonbetweendiscreteandintegratedFiltersFrequency100KHz1.0MHz10MHz100MHz1.0GHz10GHz20*LOG10(2*V(R-Receiver:1))-80-60-40-20-0Frequency100KHz1.0MHz10MHz100MHz1.0GHz10GHz20*LOG10(2*V(R-Receiver:1))-60-40-20-0DiscretePi-FilterSharpRiseSmoothRiseC10R1C2L1,parasitic12GroundparasiticL12.8nHusuallyIntegratedPi-Filter0R1L2,parasitic12NZF22OTT1ReducedparasiticL20.5nHIntegratedSolutionsTypicalparasiticinductancevspackageQFN/DFN800pH500pH100pH50pHDiscretecapacitorLeadedpackageFlipchipbumpeddieIntegratedSolutionsImportanceoftheparasiticinductanceRSCLSC=33pFRs=0.4Ω-40-35-30-25-20-15-10-5010100100010000F(MHz)S21(dB)Ls=900pHLs=500pHLs=100pHLowerparasiticinductanceenablebroadbandfilteringEquivalentcircuitofdiscretecapacitorIntegratedSolutionsBenchmarkingIntegratedSolutionsHowtoselectEMIfilterLineCapacitance–pFCapatitanceinyourdataline.Smallitbetterfordigitalsignal.Butlargeonecanhelpinsertionloss.Exp10pF,21pF,45pF……Resistance-ΩResistanceindataline.Valueismeetyourdriverbility.Largeonecanhelpinsertionloss.Exp100R,200RBreakdownVoltage–vESDprotection,nearsystemworkingvoltage.Exp5.6v6.8v……LeakageCurrent-uAPackageInordertominyourPCBarea.ExpFlipchip,DFNInsertionlossEMIattenuation.30dB–40dB@900MHzIntegratedSolutionsNUF4402MN(1.6X1.6MM)4ChannelEMIfilterDescriptionThisdeviceisa4lineEMIfilterarrayforwirelessapplications.ItalsooffersESDprotection–clampingtransientsfromstaticdischarges.ESDprotectionisprovidedacrossallcapacitors.FeaturesƒEMIFilteringandESDProtectionƒQFN1.6x1.6mmƒMoistureSensitivityLevel1ƒCapacitance(Cd):12pF@2.5VoltsƒRstarget100Ohms„Benefits•ReducesEMI/RFIEmissionsonaDataLine•IntegratedSolutionoffersCostandSpaceSavings•ReducesParasiticInductancesWhichOfferaMore“Ideal”LowPassFilterResponse•IntegratedSolutionImprovesSystemReliabilityScheduleƒPhase0approvedƒEngineeringSampleNowƒProductionDec2004Applications•WirelessPhones•PDAProducts•MP3•PortablesElectronicsIntegratedSolutionsNUF8401MN(1.6X4.0mm)8ChannelEMIfilterDescriptionThisdeviceisa8lineEMIfilterarrayforwirelessapplications.Greaterthan-25dBattenuationisobtainedatfrequenciesfrom800MHzto2.4GHz.ItalsooffersESDprotection–clampingtransientsfromstaticdischarges.ESDprotectionisprovidedacrossallcapacitors.Features