LTC4412

1LTC44124412fAPPLICATIOSUFEATURESDESCRIPTIOUTYPICALAPPLICATIOULowLossPowerPathTMControllerinThinSOTnVeryLowLossReplacementforPowerSupplyOR’ingDiodesnMinimalExternalComponentsnAutomaticSwitchingBetweenDCSourcesnSimplifiesLoadSharingwithMultipleBatteriesnLowQuiescentCurrent:11mAn3Vto28VAC/DCAdapterVoltageRangen2.5Vto28VBatteryVoltageRangenReverseBatteryProtectionnDrivesAlmostAnySizeMOSFETforWideRangeofCurrentRequirementsnMOSFETGateProtectionClampnManualControlInputnLowProfile(1mm)ThinSOTTMPackagenCellularPhonesnNotebookandHandheldComputersnDigitalCamerasnUSB-PoweredPeripheralsnUninterruptablePowerSuppliesnLogicControlledPowerSwitchTheLTC®4412controlsanexternalP-channelMOSFETtocreateanearidealdiodefunctionforpowerswitchoverorloadsharing.ThispermitshighlyefficientOR’ingofmul-tiplepowersourcesforextendedbatterylifeandlowself-heating.Whenconducting,thevoltagedropacrosstheMOSFETistypically20mV.Forapplicationswithawalladapterorotherauxiliarypowersource,theloadisauto-maticallydisconnectedfromthebatterywhentheauxiliarysourceisconnected.TwoormoreLTC4412smaybeinterconnectedtoallowloadsharingbetweenmultiplebatteriesorchargingofmultiplebatteriesfromasinglecharger.ThewidesupplyoperatingrangesupportsoperationfromonetosixLi-Ioncellsinseries.Thelowquiescentcurrent(11mAtypical)isindependentoftheloadcurrent.ThegatedriverincludesaninternalvoltageclampforMOSFETprotection.TheSTATpincanbeusedtoenableanauxiliaryP-channelMOSFETpowerswitchwhenanauxiliarysupplyisdetected.Thispinmayalsobeusedtoindicatetoamicrocontrollerthatanauxiliarysupplyisconnected.Thecontrol(CTL)inputenablestheusertoforcetheprimaryMOSFEToffandtheSTATpinlow.TheLTC4412isavailableinalowprofile(1mm)ThinSOTpackage.,LTCandLTareregisteredtrademarksofLinearTechnologyCorporation.PowerPathandThinSOTaretrademarksofLinearTechnologyCorporation.VINGNDCTLSENSEGATESTAT123654LTC4412COUTTOLOADSTATUSOUTPUTLOWWHENWALLADAPTERPRESENT470k4412F01VCC1N5819FDN306PBATTERYCELL(S)WALLADAPTERINPUTFigure1.AutomaticSwitchoverofLoadBetweenaBatteryandaWallAdapterFORWARDVOLTAGE(V)0.020CURRENT(A)1CONSTANTRON4412F01b0.5CONSTANTVOLTAGESCHOTTKYDIODELTC4412LTC4412vsSchottkyDiodeForwardVoltageDrop2LTC44124412f(Note1)SupplyVoltage(VIN)..................................–14Vto36VVoltagefromVINtoSENSE........................–28Vto28VInputVoltageCTL........................................................–0.3Vto36VSENSE....................................................–14Vto36VOutputVoltageGATE.....................–0.3VtotheHigherofVIN+0.3VorSENSE+0.3VSTAT.....................................................–0.3Vto36VOperatingAmbientTemperatureRange(Note2).............................................–40Cto85COperatingJunctionTemperature.........–40Cto125CStorageTemperatureRange.................–65Cto150CLeadTemperature(Soldering,10sec)..................300CABSOLUTEMAXIMUMRATINGS=125C,qJA=230C/WTheldenotesspecificationswhichapplyoverthefulloperatingtemperaturerange,unlessotherwisenotedspecificationsareatTA=25C,VIN=12V,CTLandGND=0V.Currentintoapinispositiveandcurrentoutofapinisnegative.AllvoltagesarereferencedtoGND,unlessotherwisespecified.ConsultLTCMarketingforpartsspecifiedwithwideroperatingtemperatureranges.ELECTRICALCHARACTERISTICSVIN1GND2CTL36SENSE5GATE4STATTOPVIEWS6PACKAGE6-LEADPLASTICTSOT-23S6PARTMARKINGLTA2SYMBOLPARAMETERCONDITIONSMINTYPMAXUNITSVIN,OperatingSupplyRangeVINand/orVSENSEMustBeinThisRangel2.528VVSENSEforProperOperationIQFLQuiescentSupplyCurrentatLowSupplyVIN=3.6V.MeasureCombinedCurrentl1119mAWhileinForwardRegulationatVINandSENSEPinsAveragedwithVSENSE=3.5VandVSENSE=3.6V(Note3)IQFHQuiescentSupplyCurrentatHighSupplyVIN=28V.MeasureCombinedCurrentl1526mAWhileinForwardRegulationatVINandSENSEPinsAveragedwithVSENSE=27.9VandVSENSE=28V(Note3)IQRLQuiescentSupplyCurrentatLowSupplyVIN=3.6V,VSENSE=3.7V.Measure1019mAWhileinReverseTurn-OffCombinedCurrentofVINandSENSEPinsIQRHQuiescentSupplyCurrentatHighSupplyVIN=27.9V,VSENSE=28V.Measure1628mAWhileinReverseTurn-OffCombinedCurrentofVINandSENSEPinsIQCLQuiescentSupplyCurrentatLowSupplyVIN=3.6V,VSENSE=0V,VCTL=1V713mAwithCTLActiveIQCHQuiescentSupplyCurrentatHighSupplyVIN=28V,VSENSE=0V,VCTL=1V1220mAwithCTLActiveILEAKVINandSENSEPinLeakageCurrentsVIN=28V,VSENSE=0V;VSENSE=28V,VIN=0V–301mAWhenOtherPinSuppliesPowerVIN=14V,VSENSE=–14V;VSENSE=14V,VIN=–14VPowerPathControllerVFRPowerPathSwitchForwardRegulationVIN–VSENSE,2.5V£VIN£28Vl102032mVVoltageVRTOPowerPathSwitchReverseTurn-OffVSENSE–VIN,2.5V£VIN£28Vl102032mVThresholdVoltage3LTC44124412fTheldenotesspecificationswhichapplyoverthefulloperatingtemperaturerange,unlessotherwisenotedspecificationsareatTA=25C,VIN=12V,CTLandGND=0V.Currentintoapinispositiveandcurrentoutofapinisnegative.AllvoltagesarereferencedtoGND,unlessotherwisespecified.ELECTRICALCHARACTERISTICSNote1:AbsoluteMaximumRatingsarethosevaluesbeyondwhichthelifeofadevicemaybeimpaired.Note2:TheLTC4412Eisguaranteedtomeetperformancespecificationsfrom0Cto70Coperatingambienttemperaturerange.Specific