LM2940低压差稳压器

January2007LM2940/LM2940C1ALowDropoutRegulatorGeneralDescriptionTheLM2940/LM2940Cpositivevoltageregulatorfeaturestheabilitytosource1Aofoutputcurrentwithadropoutvoltageoftypically0.5Vandamaximumof1Vovertheentiretemper-aturerange.Furthermore,aquiescentcurrentreductioncir-cuithasbeenincludedwhichreducesthegroundcurrentwhenthedifferentialbetweentheinputvoltageandtheoutputvoltageexceedsapproximately3V.Thequiescentcurrentwith1Aofoutputcurrentandaninput-outputdifferentialof5Visthereforeonly30mA.Higherquiescentcurrentsonlyexistwhentheregulatorisinthedropoutmode(VIN−VOUT≤3V).Designedalsoforvehicularapplications,theLM2940/LM2940Candallregulatedcircuitryareprotectedfromre-versebatteryinstallationsor2-batteryjumps.Duringlinetransients,suchasloaddumpwhentheinputvoltagecanmomentarilyexceedthespecifiedmaximumoperatingvolt-age,theregulatorwillautomaticallyshutdowntoprotectboththeinternalcircuitsandtheload.TheLM2940/LM2940Ccan-notbeharmedbytemporarymirror-imageinsertion.Familiarregulatorfeaturessuchasshortcircuitandthermaloverloadprotectionarealsoprovided.Features■Dropoutvoltagetypically0.5V@IO=1A■Outputcurrentinexcessof1A■Outputvoltagetrimmedbeforeassembly■Reversebatteryprotection■Internalshortcircuitcurrentlimit■Mirrorimageinsertionprotection■P+ProductEnhancementtestedTypicalApplication882203*Requiredifregulatorislocatedfarfrompowersupplyfilter.**COUTmustbeatleast22μFtomaintainstability.Maybeincreasedwithoutboundtomaintainregulationduringtransients.Locateascloseaspossibletotheregulator.ThiscapacitormustberatedoverthesameoperatingtemperaturerangeastheregulatorandtheESRiscritical;seecurve.OrderingInformationTempRangeOutputVoltagePackage5.08.09.01012150°C≤TJ≤125°CLM2940CT-5.0–LM2940CT-9.0–LM2940CT-12LM2940CT-15TO-220LM2940CS-5.0–LM2940CS-9.0–LM2940CS-12LM2940CS-15TO-263LM2940CSX-5.0–LM2940CSX-9.0–LM2940CSX-12LM2940CSX-15−40°C≤TJ≤125°CLM2940LD-5.0LM2940LD-8.0LM2940LD-9.0LM2940LD-10LM2940LD-12LM2940LD-15LLP1kUnitsTapeandReelLM2940LDX-5.0LM2940LDX-8.0LM2940LDX-9.0LM2940LDX-10LM2940LDX-12LM2940LDX-15LLP4.5kUnitsTapeandReel−40°C≤TJ≤125°CLM2940T-5.0LM2940T-8.0LM2940T-9.0LM2940T-10LM2940T-12–TO-220LM2940S-5.0LM2940S-8.0LM2940S-9.0LM2940S-10LM2940S-12–TO-263LM2940SX-5.0LM2940SX-8.0LM2940SX-9.0LM2940SX-10LM2940SX-12–©2007NationalSemiconductorCorporation8822−40°C≤TA≤85°CLM2940IMP-5.0LM2940IMP-8.0LM2940IMP-9.0LM2940IMP-10LM2940IMP-12LM2940IMP-15SOT-223LM2940IMPX-5.0LM2940IMPX-8.0LM2940IMPX-9.0LM2940IMPX-10LM2940IMPX-12LM2940IMPX-15SOT-223inTapeandReelMarkingL53BL54BL0EBL55BL56BL70BThephysicalsizeoftheSOT-223istoosmalltocontainthefulldevicepartnumber.Thepackagemarkingsindicatedarewhatwillappearontheactualdevice.Mil-AeroOrderingInformationTemperatureRangeOutputVoltagePackage5.08.01215−55°C≤TJ≤125°CLM2940J-5.0/8835962-8958701EA–LM2940J-12/8835962-9088401QEALM2940J-15/8835962-9088501QEAJ16ALM2940WG5.0/8835962-8958701XA–LM2940WG5-12/883LM2940WG5-15/883WG16AForinformationonmilitarytemperaturerangeproducts,pleasegototheMil/AeroWebSiteat(T)PlasticPackage882202FrontViewSeeNSPackageNumberTO3BSOT-223(MP)3-Lead882242FrontViewSeeNSPackageNumberMP04A16-LeadDual-in-LinePackage(J)882243TopViewSeeNSPackageNumberJ16A16-LeadCeramicSurface-MountPackage(WG)882244TopViewSeeNSPackageNumberWG16ATO-263(S)Surface-MountPackage882211TopViewLLP(LD)8-Lead882246Pin2andpin7arefusedtocenterDAPPin5and6needtobetiedtogetheronPCBboardTopViewSeeNSPackageNumberLDC08A882212SideViewSeeNSPackageNumberTS3B(Note1)IfMilitary/Aerospacespecifieddevicesarerequired,pleasecontacttheNationalSemiconductorSalesOffice/Distributorsforavailabilityandspecifications.LM2940S,J,WG,T,MP≤100ms60VLM2940CS,T≤1ms45VInternalPowerDissipation (Note2)InternallyLimitedMaximumJunctionTemperature150°CStorageTemperatureRange−65°C≤TJ≤+150°CSolderingTemperature(Note3)TO-220(T),Wave260°C,10sTO-263(S)235°C,30sSOT-223(MP)260°C,30sLLP-8(LD)235°C,30sESDSusceptibility(Note4)2kVOperatingConditions(Note1)InputVoltage26VTemperatureRangeLM2940T,LM2940S−40°C≤TJ≤125°CLM2940CT,LM2940CS0°C≤TJ≤125°CLM2940IMP−40°C≤TA≤85°CLM2940J,LM2940WG−55°C≤TJ≤125°CLM2940LD−40°C≤TJ≤125°CElectricalCharacteristicsVIN=VO+5V,IO=1A,CO=22μF,unlessotherwisespecified.Boldfacelimitsapplyovertheentireoperatingtemperaturerangeoftheindicateddevice.AllotherspecificationsapplyforTA=TJ=25°C.OutputVoltage(VO)5V8VUnitsLM2940LM2940/883LM2940LM2940/883ParameterConditionsTypLimitLimitTypLimitLimit(Note5)(Note6)(Note5)(Note6)6.25V≤VIN≤26V9.4V≤VIN≤26VOutputVoltage5mA≤IO≤1A5.004.85/4.754.85/4.758.007.76/7.607.76/7.60VMIN5.15/5.255.15/5.258.24/8.408.24/8.40VMAXLineRegulationVO+2V≤VIN≤26V,205040/50208050/80mVMAXIO=5mALoadRegulation50mA≤IO≤1ALM2940,LM2940/8833550/8050/1005580/13080/130mVMAXLM2940C35505580Output100mADCandImpedance20mArms,351000/1000551000/1000mΩfO=120HzQuiescentVO+2V≤VIN≤26V,CurrentIO=5mALM2940,LM2940/8831015/2015/201015/2015/20mA