LM1117800-mA,Low-DropoutLinearRegulator
1Features
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3Description
TheLM1117isalowdropoutvoltageregulatorwithadropoutof1.2Vat800mAofloadcurrent.
TheLM1117isavailableinanadjustableversion,whichcansettheoutputvoltagefrom1.25to13.8Vwithonlytwoexternalresistors.Inaddition,itisavailableinfivefixedvoltages,1.8V,2.5V,3.3V,and5V.
TheLM1117offerscurrentlimitingandthermalshutdown.ItscircuitincludesaZenertrimmedbandgapreferencetoassureoutputvoltageaccuracytowithin±1%.
Aminimumof10-μFtantalumcapacitorisrequiredattheoutputtoimprovethetransientresponseandstability.
DeviceInformation(1)
PARTNUMBER
PACKAGESOT-223(4)TO-220(3)
LM1117,LM1117I
TO-252(3)WSON(8)TO-263(3)
BODYSIZE(NOM)6.50mm×3.50mm14.986mm×10.16mm6.58mm×6.10mm4.00mm×4.00mm10.18mm×8.41mm
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Foranewerdrop-inalternative,seetheTLV1117Availablein1.8V,2.5V,3.3V,5V,andAdjustableVersions
Space-savingSOT-223andWSONpackagesCurrentlimitingandthermalprotectionOutputcurrent:800mA
Lineregulation:0.2%(maximum)Loadregulation:0.4%(maximum)Temperaturerange:
–LM1117:0°Cto125°C–LM1117I:?40°Cto125°C
2Applications
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ACdrivepowerstagemodulesMerchantnetworkandserverPSUIndustrialAC/DCUltrasoundscanners
Servodrivecontrolmodules
(1)Forallavailablepackages,seetheorderableaddendumat
theendofthedatasheet.
AdjustableOutputRegulator
LM1117
SNOS412O–FEBRUARY2000–REVISEDJUNE2020
7Specifications
7.1AbsoluteMaximumRatings
overoperatingfree-airtemperaturerange(unlessotherwisenoted)(1)
MIN
MaximumInputVoltage(VINtoGND)PowerDissipation(2)
JunctionTemperature(TJ)(2)StorageTemperature,Tstg(1)(2)
–65
MAX20
InternallyLimited
150150
°C°CUNITV
StressesbeyondthoselistedunderAbsoluteMaximumRatingsmaycausepermanentdamagetothedevice.Thesearestressratingsonly,whichdonotimplyfunctionaloperationofthedeviceattheseoranyotherconditionsbeyondthoseindicatedunderRecommendedOperatingConditions.Exposuretoabsolute-maximum-ratedconditionsforextendedperiodsmayaffectdevicereliability.
ThemaximumpowerdissipationisafunctionofTJ(max),RθJA,andTA.ThemaximumallowablepowerdissipationatanyambienttemperatureisPD=(TJ(max)–TA)/RθJA.AllnumbersapplyforpackagessoldereddirectlyintoaPCB.
7.2ESDRatings
VALUE
V(ESD)(1)
Electrostaticdischarge
Human-bodymodel(HBM),perANSI/ESDA/JEDECJS-001(1)
±2000
UNITV
JEDECdocumentJEP155statesthat500-VHBMallowssafemanufacturingwithastandardESDcontrolprocess.Pinslistedas±2000Vmayactuallyhavehigherperformance.
7.3RecommendedOperatingConditions
overoperatingfree-airtemperaturerange(unlessotherwisenoted)
MIN
InputVoltage(VINtoGND)JunctionTemperature(TJ)(1)(1)
LM1117LM1117I
0?40
MAX15125125
UNITV°C
ThemaximumpowerdissipationisafunctionofTJ(max),RθJA,andTA.ThemaximumallowablepowerdissipationatanyambienttemperatureisPD=(TJ(max)–TA)/RθJA.AllnumbersapplyforpackagessoldereddirectlyintoaPCB.
7.4ThermalInformation
LM1117,LM1117I
THERMALMETRIC(1)
DCY(SOT-223)4PINS
RθJARθJC(top)RθJBψJTψJBRθJC(bot)
Junction-to-ambientthermalresistanceJunction-to-case(top)thermalresistanceJunction-to-boardthermalresistanceJunction-to-topcharacterizationparameterJunction-to-boardcharacterizationparameterJunction-to-case(bottom)thermalresistance
61.642.510.42.910.3—
NDE(TO-220)3PINS23.816.65.33.15.31.5
NDP(TO-252)3PINS45.152.129.84.529.41.3
NGN(WSON)8PINS39.331.416.50.316.75.6
KTT(TO-263)3PINS41.344.124.210.923.21.3
°C/W°C/W°C/W°C/W°C/W°C/WUNIT
(1)
Formoreinformationabouttraditionalandnewthermalmetrics,seetheSemiconductorandICpackagethermalmetricsapplicationreport.
7.5LM1117ElectricalCharacteristics
unlessotherwisespecified,TJ=25°C.
PARAMETER
TESTCONDITIONS
LM1117-ADJ
IOUT=10mA,VIN–VOUT=2V,TJ=25°C
VREF
ReferenceVoltage
LM1117-ADJ
10mA≤IOUT≤800mA,1.4V≤VIN–VOUT≤10V
TJ=25°C
overthejunctiontemperaturerange0°Cto125°C
1.225MIN(1)1.238
TYP(2)1.251.25
1.27MAX(1)1.262
VUNIT
(1)(2)Alllimitsareensuredbytestingorstatisticalanalysis.
TypicalValuesrepresentthemostlikelyparametricnormal.
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Copyright?2000–2020,TexasInstrumentsIncorporated
LM1117
SNOS412O–FEBRUARY2000–REVISEDJUNE2020
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LM1117
SNOS412O–FEBRUARY2000–REVISEDJUNE2020
10PowerSupplyRecommendations
TheinputsupplytotheLM1117mustbekeptatavoltagelevelsuchthatitsmaximumratingisnotexceeded.TheminimumdropoutvoltagemustalsobemetwithextraheadroomwhenpossibletokeeptheLM1117inregulation.Aninputcapacitorisrecommended.Formoreinformationregardingcapacitorselection,refertoExternalCapacitors.
11Layout
11.1LayoutGuidelines
Somelayoutguidelinesmustbefollowedtoensureproperregulationoftheoutputvoltagewithminimumnoise.TracescarryingtheloadcurrentmustbewidetoreducetheamountofparasitictraceinductanceandthefeedbackloopfromVOUTtoADJmustbekeptasshortaspossible.ToimprovePSRR,abypasscapacitorcanbeplacedattheADJpinandmustbelocatedascloseaspossibletotheIC.IncaseswhenVINshortstoground,anexternaldiodemustbeplacedfromVOUTtoVINtodivertthesurgecurrentfromtheoutputcapacitorandprotecttheIC.ThediodemustbeplacedclosetothecorrespondingICpinstoincreasetheireffectiveness.11.1.1HeatsinkRequirements
Whenanintegratedcircuitoperateswithanappreciablecurrent,itsjunctiontemperatureiselevated.Itisimportanttoquantifyitsthermallimitsinordertoachieveacceptableperformanceandreliability.Thislimitisdeterminedbysummingtheindividualpartsconsistingofaseriesoftemperaturerisesfromthesemiconductorjunctiontotheoperatingenvironment.Aone-dimensionalsteady-statemodelofconductionheattransferisdemonstratedinFigure22.Theheatgeneratedatthedevicejunctionflowsthroughthedietothedieattachpad,throughtheleadframetothesurroundingcasematerial,totheprintedcircuitboard,andeventuallytotheambientenvironment.Belowisalistofvariablesthatmayaffectthethermalresistanceandinturntheneedforaheatsink.
Table1.ComponentandApplicationVariables
RθJC(COMPONENTVARIABLES)
LeadframeSizeandMaterialNo.ofConductionPinsDieSize
DieAttachMaterial
MoldingCompoundSizeandMaterial
RθJA(APPLICATIONVARIABLES)
MountingPadSize,Material,andLocationPlacementofMountingPadPCBSizeandMaterialTracesLengthandWidthAdjacentHeatSourcesVolumeofAirAmbientTemperatueShapeofMountingPad
Thecasetemperatureismeasuredatthepointwheretheleadscontactwiththemountingpadsurface
Figure22.Cross-SectionalViewofIntegratedCircuitMountedonaPrintedCircuitBoard
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LM1117
SNOS412O–FEBRUARY2000–REVISEDJUNE2020
TheLM1117regulatorshaveinternalthermalshutdowntoprotectthedevicefromover-heating.Underallpossibleoperatingconditions,thejunctiontemperatureoftheLM1117mustbewithintherangeof0°Cto125°C.Aheatsinkmayberequireddependingonthemaximumpowerdissipationandmaximumambienttemperatureoftheapplication.Todetermineifaheatsinkisneeded,thepowerdissipatedbytheregulator,PD,mustbecalculated:
IIN=IL+IG
PD=(VIN-VOUT)IL+VINIG
(2)(3)
Figure23showsthevoltagesandcurrentswhicharepresentinthecircuit.
Figure23.PowerDissipationDiagram
Thenextparameterwhichmustbecalculatedisthemaximumallowabletemperaturerise,TR(max):
TR(max)=TJ(max)-TA(max)
where
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TJ(max)isthemaximumallowablejunctiontemperature(125°C)whichwillbeencounteredintheapplicationTA(max)isthemaximumambienttemperaturewhichwillbeencounteredintheapplication(4)
UsingthecalculatedvaluesforTR(max)andPD,themaximumallowablevalueforthejunction-to-ambient
thermalresistance(RθJA)canbecalculated:
RθJA=TR(max)/PD
(5)
ForthemaximumallowablevalueforθJA,refertotheThermalInformationtable.
Asadesignaid,Table2showsthevalueoftheθJAofSOT-223andTO-252fordifferentheatsinkarea.Figure24andFigure25reflectsthesametestresultsaswhatareintheTable2
Figure26andFigure27showsthemaximumallowablepowerdissipationvs.ambienttemperaturefortheSOT-223andTO-252device.Figure28andFigure29showsthemaximumallowablepowerdissipationvs.copperarea(in2)fortheSOT-223andTO-252devices.PleaseseeAN1028forpowerenhancementtechniquestobeusedwithSOT-223andTO-252packages.
TheAN-1187LeadlessLeadframePackage(LLP)applicationnotediscussesimprovedthermalperformanceandpowerdissipationfortheWSON.
Table2.RθJADifferentHeatsinkArea
LAYOUT
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(1)
0.01230.0660.30.530.7610000
COPPERAREA
TopSide(in2)(1)
BottomSide(in2)
0000000.20.40.60.8
THERMALRESISTANCE
(θJA,°C/W)SOT-223
13612384756966115988982
(θJA,°C/W)TO-252
103876054524784706357
Tabofdeviceattachedtotopsidecopper
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MEMORY存储芯片LM1117IMPX-3.3-NOPB中文规格书 - 图文
