©SemiconductorComponentsIndustries,LLC,2007February,2007−Rev.11PublicationOrderNumber:NCP1605/DNCP1605Enhanced,HighVoltageandEfficientStandbyMode,PowerFactorControllerTheNCP1605isacontrollerthatexhibitsnear−unitypowerfactorwhileoperatinginfixedfrequency,DiscontinuousConductionMode(DCM)orinCriticalConductionMode(CRM).HousedinaSOIC−16package,thecircuitincorporatesallthefeaturesnecessaryforbuildingrobustandcompactPFCstages,withaminimumofexternalcomponents.Inaddition,itintegratestheskipcyclecapabilitytolowerthestandbylossestoaminimum.GeneralFeatures•Near−UnityPowerFactor•FixedFrequency,DiscontinuousConductionModeOperation•CriticalConductionModeAchievableinMostStressfulConditions•LosslessHighVoltageCurrentSourceforStartup•SoftSkipCycleforLowPowerStandbyMode•SwitchingFrequencyupto250kHz•SynchronizationCapability•FastLine/LoadTransientCompensation•ValleyTurnOn•HighDriveCapability:−500mA/+800mA•SignaltoIndicatethatthePFCisReadyforOperation(“pfcOK”Pin)•VCCrange:from10Vto20V•FollowerBoostOperation•ThisisaPb−FreeDeviceSafetyFeatures•OutputUnderandOvervoltageProtection•Brown−OutDetection•Soft−StartforSmoothStartupOperation•OvercurrentLimitation•ZeroCurrentDetectionProtectingthePFCstagefromInrushCurrents•ThermalShutdown•LatchedOffCapabilityTypicalApplications•PCPowerSupplies•AllOffLineAppliancesRequiringPowerFactorCorrection−16DSUFFIXCASE751BDevicePackageShipping†ORDERINGINFORMATIONMARKINGDIAGRAMA=AssemblyLocationWL=WaferLotY=YearWW=WorkWeekG=Pb−FreePackage1NCP1605AWLYWWG123456781615141211109(TopView)CSinSTBYBOVcontrolFBCSout/ZCDCtOSC/SYNCHVNCpfcOK/REF5VVCCGNDOVP/UVPDRV13STDWNPINCONNECTIONS†Forinformationontapeandreelspecifications,includingpartorientationandtapesizes,pleaserefertoourTapeandReelPackagingSpecificationBrochure,BRD8011/D.1NCP1605DR2GSOIC−16(Pb−Free)2500/Tape&Reel16NCP1605−0.3,+20V10Themaximumtransientvoltage(Note1)VCC−0.3,+25V1,2,4,6,7,8,13and14InputVoltageVI−0.3,+9V3VCONTROLPinVCONTROL−0.3,VCONTROLMAX(Note1)V16HighVoltagePinHV−0.3,+500VPowerDissipationandThermalCharacteristics:MaximumPowerDissipation@TA=70°CThermalResistanceJunction−to−AirPDRJA550145mW°C/WOperatingJunctionTemperatureRangeTJ−40,+125°CMaximumJunctionTemperatureTJmax150°CStorageTemperatureRangeTSmax−65to150°°CLeadTemperature(Soldering,10s)TLmax300°CStressesexceedingMaximumRatingsmaydamagethedevice.MaximumRatingsarestressratingsonly.FunctionaloperationabovetheRecommendedOperatingConditionsisnotimplied.ExtendedexposuretostressesabovetheRecommendedOperatingConditionsmayaffectdevicereliability.1.“VCONTROLMAX”isthepinclampvoltageNCP1605(typically,aportionofthefeedbacksignalofthedownstreamconverterorafilteredportionoftheSMPSdrivepulses)shouldbeappliedtoPin1.WhenthePin3voltagegoesbelow300mV,thecircuitentersaburstmodeoperationwherethebulkvoltagevariesbetweentheregulationvoltageand95.5%ofthislevel.2Brown−Out/InhibitionApplyaportionoftheaveragedinputvoltagetodetectbrown−outconditions.IfVPin2islowerthan0.5V,thecircuitstopspulsinguntilVPin2exceeds1V(0.5Vhysteresis).GroundPin6todisablethepart.3VCONTROL/Soft−StartTheerroramplifieroutputisavailableonthisPin.Thecapacitorconnectedbetweenthispinandgroundadjuststheregulationloopbandwidththatistypicallysetbelow20HztoachievehighPowerFactorratios.Pin3isgroundedwhenthecircuitisoffsothatwhenitstartsoperation,thepowerincreasesslowly(soft−start).4FeedbackThispinreceivesaportionofthepre−converteroutputvoltage.Thisinformationisusedfortheregulationandthe“outputlow”detection(VOUTL)thatdrasticallyspeeduptheloopresponsewhentheoutputvoltagedropsbelow95.5%ofthewishedlevel.5CurrentSenseInputThispinmonitorsanegativevoltageproportionaltothecoilcurrent.Thissignalissensedtolimitthemaximumcoilcurrentanddetectthecorereset(coildemagnetization).6CurrentSenseOutputThispinsourcesthePin5current.PlacearesistorbetweenPin6andgroundtobuildthevoltageproportionaltothecoilcurrentanddetectthecorereset.TheimpedancebetweenPin6andgroundshouldnotexceed3timesthatofthePin5toground.YoucanfurtherapplythevoltagefromanauxiliarywindingtoimprovethevalleydetectionoftheMOSFETdrainsourcevoltage.7Ct(Ramp)Thecircuitcontrolsthepowerswitchon−timebycomparingthePin7ramptoaninternalvoltage(“Vton”)derivedfromtheregulationblockandthesensed“dcycle”(relativedurationofthecurrentcycleoverthecorrespondingswitchingperiod).Pin7sourcesacurrentproportionaltothesquaredoutputvoltagetoallowtheFollowerBoostoperation(optional)wherethePFCoutputvoltagestabilizesatalevelthatvarieslinearlyversustheaclineamplitude.Thistechniquereducesthedifferencebetweentheoutputandinputvoltages,tooptimizetheboostefficiencyandminimizethesizeandcostofthePFCstage8Oscillator/synchronizationConnectacapacitororapplyasynchronizationsignaltothispintosett