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SGx524RegulatingPulse-WidthModulators1FeaturesCompletePulse-WidthModulation(PWM)power-controlcircuitryUncommittedoutputsforsingle-endedorpush-pullapplications8-mA(TYP)standbycurrent2ApplicationsTransformer-coupledDC/DCconvertorsSwitching-regulatorsofanypolarity3DescriptionTheSG2524andSG3524devicesincorporateallthefunctionsrequiredintheconstructionofaregulatingpowersupply,inverter,orswitchingregulatoronasinglechip.
Theyalsocanbeusedasthecontrolelementforhigh-power-outputapplications.
TheSG2524andSG3524weredesignedforswitchingregulatorsofeitherpolarity,transformer-coupleddc-to-dcconverters,transformerlessvoltagedoublers,andpolarity-converterapplicationsemployingfixed-frequency,pulse-widthmodulation(PWM)techniques.
Thecomplementaryoutputallowseithersingle-endedorpush-pullapplication.
Eachdeviceincludesanon-chipregulator,erroramplifier,programmableoscillator,pulse-steeringflip-flop,twouncommittedpasstransistors,ahigh-gaincomparator,andcurrent-limitingandshutdowncircuitry.
DeviceInformationPARTNUMBERPACKAGE(PIN)BODYSIZE(NOM)SGx524SOIC(16)9.
90mm*3.
91mmPDIP(16)9.
90mm*6.
35mmNS(16)10.
30mm*5.
30mmTypicalApplicationSchematicwww.
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comSG2524,SG3524SLVS077F–APRIL1977–REVISEDJANUARY2021Copyright2021TexasInstrumentsIncorporatedSubmitDocumentFeedback1SG2524,SG3524SLVS077F–APRIL1977–REVISEDJANUARY2021AnIMPORTANTNOTICEattheendofthisdatasheetaddressesavailability,warranty,changes,useinsafety-criticalapplications,intellectualpropertymattersandotherimportantdisclaimers.
PRODUCTIONDATA.
TableofContents1Features.
12Applications.
13Description.
14RevisionHistory.
25PinConfigurationsandFunctions.
2PinFunctions.
26Specifications.
46.
1AbsoluteMaximumRatings.
46.
2ESDRatings.
46.
3RecommendedOperatingConditions.
46.
4ThermalInformation.
4757.
1ElectricalCharacteristics.
57.
2ElectricalCharacteristics—Continued,BothParts.
.
.
.
67.
3TypicalCharacteristics.
78ParameterMeasurementInformation.
88.
189DetailedDescription.
99.
1Overview.
99.
2FunctionalBlockDiagram.
99.
3FeatureDescription.
109.
4DeviceFunctionalModes.
1110Layout.
1910.
1LayoutGuidelines.
1910.
2LayoutExample.
2011DeviceandDocumentationSupport.
2111.
1RelatedLinks.
2111.
2Trademarks.
214RevisionHistoryChangesfromRevisionE(January2015)toRevisionF(February2021)PageUpdatedtext.
6ChangesfromRevisionD(February2003)toRevisionE(January2015)PageAddedApplications,DeviceInformationtable,PinFunctionstable,ESDRatingstable,ThermalInformationtable,TypicalCharacteristics,FeatureDescriptionsection,DeviceFunctionalModes,ApplicationandImplementationsection,PowerSupplyRecommendationssection,Layoutsection,DeviceandDocumentationSupportsection,andMechanical,Packaging,andOrderableInformationsection.
1DeletedOrderingInformationtable.
15PinConfigurationsandFunctionsPinFunctionsPINTYPEDESCRIPTIONNAMENO.
COL112OCollectorterminalofBJToutput1COL213OCollectorterminalofBJToutput2COMP9I/OErroramplifiercompensationpinCT7—CapacitorterminalusedtosetoscillatorfrequencyCURRLIM+4IPositivecurrentlimitingamplifierinputCURRLIM-5INegativecurrentlimitingamplifierinputSG2524,SG3524SLVS077F–APRIL1977–REVISEDJANUARY2021www.
ti.
com2SubmitDocumentFeedbackCopyright2021TexasInstrumentsIncorporatedPINTYPEDESCRIPTIONNAMENO.
EMIT111OEmitterterminalofBJToutput1EMIT214OEmitterterminalofBJToutput2GND8—GroundIN+2IPositiveerroramplifierinputIN-1IPositiveerroramplifierinputOSCOUT3OOscillatorOutputREFOUT16OReferenceregulatoroutputRT6—ResistorterminalusedtosetoscillatorfrequencySHUTDOWN10IDeviceshutdownVCC15—Positivesupplywww.
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comSG2524,SG3524SLVS077F–APRIL1977–REVISEDJANUARY2021Copyright2021TexasInstrumentsIncorporatedSubmitDocumentFeedback36Specifications6.
1AbsoluteMaximumRatingsoveroperatingfree-airtemperaturerange(unlessotherwisenoted)(1)MINMAXUNITVCCSupplyvoltage40VICCCollectoroutputcurrent100mAIO(ref)Referenceoutputcurrent50mACurrentthroughCTterminal–5mATJMaximumjunctiontemperature150°CLeadtemperature1,6mm(1/16inch)fromcasefor10seconds260°CTstgStoragetemperaturerange–65150°C(1)StressesbeyondthoselistedunderSection6.
1tablemaycausepermanentdamagetothedevice.
Thesearestressratingsonly,andfunctionaloperationofthedeviceattheseoranyotherconditionsbeyondthoseindicatedunderSection6.
3tablearenotimplied.
Exposuretoabsolute-maximum-ratedconditionsforextendedperiodsmayaffectdevicereliability.
6.
2ESDRatingsVALUEUNITV(ESD)ElectrostaticdischargeHumanbodymodel(HBM),perANSI/ESDA/JEDECJS-001,allpins(1)1000VChargeddevicemodel(CDM),perJEDECspecificationJESD22-C101,allpins(2)1000(1)JEDECdocumentJEP155statesthat500-VHBMallowssafemanufacturingwithastandardESDcontrolprocess.
(2)JEDECdocumentJEP157statesthat250-VCDMallowssafemanufacturingwithastandardESDcontrolprocess.
6.
3RecommendedOperatingConditionsoveroperatingfree-airtemperaturerange(unlessotherwisenoted)MINMAXUNITVCCSupplyVoltage840VReferenceoutputcurrent050mACurrentthroughCTterminal–0.
03–2mARTTimingresistor1.
8100kΩCTTimingcapacitor0.
0010.
1FTAOperatingfree-airtemperatureSG2524–2585°CSG35240706.
4ThermalInformationTHERMALMETRIC(1)SGx524UNITDNNS16PINSRθJAJunction-to-ambientthermalresistance(2)(3)736764°C/W(1)Formoreinformationabouttraditionalandnewthermalmetrics,seetheICPackageThermalMetricsapplicationreport,SPRA953.
(2)MaximumpowerdissipationisafunctionofTJ(max),θJA,andTA.
ThemaximumallowablepowerdissipationatanyallowableambienttemperatureisPD=(TJ(max)–TA)/θJA.
OperationattheabsolutemaximumTJof150°Ccanimpactreliability.
(3)ThepackagethermalimpedanceiscalculatedinaccordancewithJESD51-7.
SG2524,SG3524SLVS077F–APRIL1977–REVISEDJANUARY2021www.
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1ElectricalCharacteristicsoveroperatingfree-airtemperaturerange,VCC=20V,f=20kHz(unlessotherwisenoted)PARAMETERTESTCONDITIONS(2)SG2524SG3524UNITMINTYP(2)MAXMINTYP(1)MAXReferencesectionOutputvoltage4.
855.
24.
655.
4VInputRegulationVCC=8Vto40V10201030mVRipplerejectionf=120Hz6666dBOutputregulationIO=0mAto20mA20502050mVOutputvoltagechangewithtemperatureTA=MINtoMAX0.
3%1%0.
3%1%Short-circuitoutputcurrent(3)Vref=0100100mAErrorAmplifiersectionVIOInputoffsetvoltageVIC=2.
5V0.
55210mVIIBInputbiascurrentVIC=2.
5V210210AOpen-loopvoltageamplification72806080dBVICRCommon-mondeinputvoltagerangeTA=25°C1.
8to3.
41.
8to3.
4VCMMRCommon-moderejectionratio7070dBB1Unity-gainbandwidth33MHzOutputswingTA=25°C0.
53.
80.
53.
8V(1)Alltypicalvalues,exceptfortemperaturecoefficients,areatTA=25°C.
(2)ForconditionsshownasMINorMAX,usetheappropriatevaluespecifiedunderrecommendedoperatingconditions.
(3)Standarddeviationisameasureofthestatisticaldistributionaboutthemean,asderivedfromtheformula:www.
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comSG2524,SG3524SLVS077F–APRIL1977–REVISEDJANUARY2021Copyright2021TexasInstrumentsIncorporatedSubmitDocumentFeedback57.
2ElectricalCharacteristics—Continued,BothPartsoveroperatingfree-airtemperaturerange,VCC=20V,f=20kHz(unlessotherwisenoted)PARAMETERTESTCONDITIONS(2)MINTYP(1)MAXUNITOscillatorsectionfOSCOscillatorfrequencyCT=0.
001μF,RT=2kΩ450kHzStandarddeviationoffrequency(3)Allvaluesofvoltage,temperature,resistance,andcapacitanceconstant5—ΔfOSCFrequencychangewithvoltageVCC=8Vto40V,TA=25°C1%—FrequencychangewithtemperatureTA=MINtoMAX2%OutputamplitudeatOSCOUTTA=25°C3.
5VtWOutputpulseduration(width)atOSCOUTCT=0.
01μF,TA=25°C0.
5sOutputsectionV(BR)CECollector-emitterbreakdownvoltage40VCollectoroff-statecurrentVCE=40V0.
0150AVsatCollector-emittersaturationvoltageIC=50mA12VVOEmitteroutputvoltageVC=20V,IE=–250μA1718VtrTurn-offvoltagerisetimeRC=2kΩ0.
2stfTurn-onvoltagefalltimeRC=2kΩ0.
1sComparatorsectionMaximumdutycycle,eachoutput45%VITInputthresholdvoltageatCOMPZerodutycycle1VMaximumdutycycle3.
5IIBInputbiascurrent–1ACurrentlimitingsectionVIInputvoltagerange–11VV(SENSE)SensevoltageatTA=25°CV(IN+)–V(IN–)≥50mVV(COMP)2V175200225mVTemperaturecoefficientofsensevoltage0.
2mV/°CTotalDeviceIstStandbycurrentVCC=40V,IN–,CURRLIM+,CT,GND,COMP,EMIT1,EMIT2grounded,IN+at2V,Allotherinputsandoutputsopen810mASG2524,SG3524SLVS077F–APRIL1977–REVISEDJANUARY2021www.
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3TypicalCharacteristicsFigure7-1.
Open-LoopVoltageAmplificationofErrorAmplifiervsFrequencyFigure7-2.
OscillatorFrequencyvsTimingResistancewww.
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1Figure8-1.
GeneralTestCircuitFigure8-2.
SwitchingTimesSG2524,SG3524SLVS077F–APRIL1977–REVISEDJANUARY2021www.
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com8SubmitDocumentFeedbackCopyright2021TexasInstrumentsIncorporated9DetailedDescription9.
1OverviewSGx524isafixed-frequencypulse-width-modulation(PWM)voltage-regulatorcontrolcircuit.
Theregulatoroperatesatafixedfrequencythatisprogrammedbyonetimingresistor,RT,andonetimingcapacitor,CT.
RTestablishesaconstantchargingcurrentforCT.
ThisresultsinalinearvoltagerampatCT,whichisfedtothecomparator,providinglinearcontroloftheoutputpulseduration(width)bytheerroramplifier.
TheSGx524containsanonboard5-Vregulatorthatservesasareference,aswellassupplyingtheSGx524internalregulatorcontrolcircuitry.
Theinternalreferencevoltageisdividedexternallybyaresistorladdernetworktoprovideareferencewithinthecommon-moderangeoftheerroramplifierasshowninFigure10-5,oranexternalreferencecanbeused.
Theoutputissensedbyasecondresistordividernetworkandtheerrorsignalisamplified.
ThisvoltageisthencomparedtothelinearvoltagerampatCT.
Theresultingmodulatedpulseoutofthehigh-gaincomparatorthenissteeredtotheappropriateoutputpasstransistor(Q1orQ2)bythepulse-steeringflip-flop,whichissynchronouslytoggledbytheoscillatoroutput.
Theoscillatoroutputpulsealsoservesasablankingpulsetoensurebothoutputsareneveronsimultaneouslyduringthetransitiontimes.
ThedurationoftheblankingpulseiscontrolledbythevalueofCT.
Theoutputsmaybeappliedinapush-pullconfigurationinwhichtheirfrequencyisone-halfthatofthebaseoscillator,orparalleledforsingle-endedapplicationsinwhichthefrequencyisequaltothatoftheoscillator.
Theoutputoftheerroramplifiersharesacommoninputtothecomparatorwiththecurrent-limitingandshut-downcircuitryandcanbeoverriddenbysignalsfromeitheroftheseinputs.
ThiscommonpointispinnedoutexternallyviatheCOMPpin,whichcanbeemployedtoeithercontrolthegainoftheerroramplifierortocompensateit.
Inaddition,theCOMPpincanbeusedtoprovideadditionalcontroltotheregulator.
9.
2FunctionalBlockDiagramA.
Resistorvaluesshownarenominal.
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3FeatureDescription9.
3.
1BlankingTheoutputpulseoftheoscillatorisusedasablankingpulseattheoutput.
ThispulsedurationiscontrolledbythevalueofCTasshowninFigure7-2.
IfsmallvaluesofCTarerequired,theoscillatoroutputpulsedurationcanbemaintainedbyapplyingashuntcapacitancefromOSCOUTtoground.
9.
3.
2ErrorAmplifierTheerroramplifierisadifferential-inputtransconductanceamplifier.
TheoutputisavailableforDCgaincontrolorACphasecompensation.
Thecompensationnode(COMP)isahigh-impedancenode(RL=5MΩ).
ThegainoftheamplifierisAV=(0.
002Ω–1)RLandeasilycanbereducedfromanominal10,000byanexternalshuntresistancefromCOMPtoground.
RefertoFigure7-1fordata.
9.
3.
3CompensationCOMP,aspreviouslydiscussed,ismadeavailableforcompensation.
Sincemostoutputfiltersintroduceoneormoreadditionalpolesatfrequenciesbelow200Hz,whichisthepoleoftheuncompensatedamplifier,introductionofazerotocanceloneoftheoutputfilterpolesisdesirable.
ThiscanbeaccomplishedbestwithaseriesRCcircuitfromCOMPtogroundintherangeof50kΩand0.
001μF.
Otherfrequenciescanbecanceledbyuseoftheformulaf≈1/RC.
9.
3.
4OutputCircuitrySGx524containstwoidenticalnpntransistors,thecollectorsandemittersofwhichareuncommitted.
Eachtransistorhasantisaturationcircuitrythatlimitsthecurrentthroughthattransistortoamaximumof100mAforfastresponse.
9.
3.
5CurrentLimitingAcurrent-limitingsenseamplifierisprovidedintheSGx524device.
Thecurrent-limitingsenseamplifierexhibitsathresholdof200mV±25mVandmustbeappliedinthegroundlinesincethevoltagerangeoftheinputsislimitedto1Vto–1V.
Cautionshouldbetakentoensurethe–1-Vlimitisnotexceededbyeitherinput,otherwise,damagetothedevicemayresult.
FoldbackcurrentlimitingcanbeprovidedwiththenetworkshowninFigure9-1.
Thecurrent-limitschematicisshowninFigure9-2.
Figure9-1.
FoldbackCurrentLimitingforShortedOutputConditionsSG2524,SG3524SLVS077F–APRIL1977–REVISEDJANUARY2021www.
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com10SubmitDocumentFeedbackCopyright2021TexasInstrumentsIncorporatedFigure9-2.
Current-LimitSchematic9.
4DeviceFunctionalModes9.
4.
1SynchronousOperationWhenanexternalclockisdesired,aclockpulseofapproximately3Vcanbeapplieddirectlytotheoscillatoroutputterminal.
Theimpedancetogroundatthispointisapproximately2kΩ.
Inthisconfiguration,RTCTmustbeselectedforaclockperiodslightlygreaterthanthatoftheexternalclock.
IftwoormoreSGx524regulatorsareoperatedsynchronously,alloscillatoroutputterminalsmustbetiedtogether.
TheoscillatorprogrammedfortheminimumclockperiodisthemasterfromwhichalltheotherSGx524soperate.
Inthisapplication,theCTRTvaluesoftheslavedregulatorsmustbesetforaperiodapproximately10%longerthanthatofthemasterregulator.
Inaddition,CT(master)=2CT(slave)toensurethatthemasteroutputpulse,whichoccursfirst,hasalongerpulsedurationand,subsequently,resetstheslaveregulators.
9.
4.
2ShutdownCircuitryCOMPalsocanbeemployedtointroduceexternalcontroloftheSGx524.
Anycircuitthatcansink200μAcanpullthecompensationterminaltogroundand,thus,disabletheSGx524.
Inadditiontoconstant-currentlimiting,CURRLIM+andCURRLIM–alsocanbeusedintransformer-coupledcircuitstosenseprimarycurrentandshortenanoutputpulseshouldtransformersaturationoccur.
CURRLIM–alsocanbegroundedtoconvertCURRLIM+intoanadditionalshutdownterminal.
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TI'scustomersareresponsiblefordeterminingsuitabilityofcomponentsfortheirpurposes.
Customersshouldvalidateandtesttheirdesignimplementationtoconfirmsystemfunctionality.
10.
1ApplicationInformationThereareawidevarietyofoutputconfigurationspossiblewhenconsideringtheapplicationoftheSG2524asavoltage-regulatorcontrolcircuit.
Theycanbesegregatedintothreebasiccategories:Capacitor-diode-coupledvoltagemultipliersInductor-capacitor-implementedsingle-endedcircuitsTransformer-coupledcircuitsExamplesofthesecategoriesareshowninFigure10-1,Figure10-2,andFigure10-3,respectively.
Section10.
2demonstrateshowtosetuptheSG2524foracapacitor-diodeoutputdesign.
ThesametechniquesforsettinguptheinternalcircuitryoftheICmayalsobeusedfortheothertwooutputstageexamplesshownSection10.
3.
Figure10-1.
Capacitor-Diode-CoupledVoltage-MultiplierOutputStagesSG2524,SG3524SLVS077F–APRIL1977–REVISEDJANUARY2021www.
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com12SubmitDocumentFeedbackCopyright2021TexasInstrumentsIncorporatedFigure10-2.
Single-EndedInductorCircuitFigure10-3.
Transformer-CoupledOutputswww.
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2TypicalApplication10.
2.
1Capacitor-DiodeOutputFigure10-4.
Capacitor-DiodeOutputCircuitSchematic10.
2.
1.
1DesignRequirements15-Vsupplyvoltage–5-Voutputvoltage10.
2.
1.
2DetailedDesignProcedure10.
2.
1.
2.
1OscillatorTheoscillatorcontrolsthefrequencyoftheSG2524andisprogrammedbyRTandCTasshowninFigure10-6.
(1)whereRTisinkΩCTisinμFfisinkHzPracticalvaluesofCTfallbetween0.
001μFand0.
1μF.
PracticalvaluesofRTfallbetween1.
8kΩand100kΩ.
Thisresultsinafrequencyrangetypicallyfrom130Hzto722kHz.
10.
2.
1.
2.
2VoltageReferenceThe5-Vinternalreferencecanbeemployedbyuseofanexternalresistordividernetworktoestablishareferencecommon-modevoltagerange(1.
8Vto3.
4V)withintheerroramplifiers(seeFigure10-5),oranexternalreferencecanbeapplieddirectlytotheerroramplifier.
Foroperationfromafixed5-Vsupply,theinternalreferencecanbebypassedbyapplyingtheinputvoltagetoboththeVCCandVREFterminals.
Inthisconfiguration,however,theinputvoltageislimitedtoamaximumof6V.
SG2524,SG3524SLVS077F–APRIL1977–REVISEDJANUARY2021www.
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com14SubmitDocumentFeedbackCopyright2021TexasInstrumentsIncorporatedFigure10-5.
Error-AmplifierBiasCircuits10.
2.
1.
3ApplicationCurvesFigure10-6.
OutputDeadTimevsTimingCapacitancewww.
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3ExamplesofOtherOutputStages10.
3.
1FlybackConverterFigure10-7.
FlybackConverterCircuitSchematic10.
3.
2Single-EndedLCFigure10-8.
Single-EndedLCCircuitSchematicSG2524,SG3524SLVS077F–APRIL1977–REVISEDJANUARY2021www.
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3.
3Push-PullTransformer-CoupledFigure10-9.
Push-PullTransformer-CoupledCircuitSchematicwww.
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comSG2524,SG3524SLVS077F–APRIL1977–REVISEDJANUARY2021Copyright2021TexasInstrumentsIncorporatedSubmitDocumentFeedback17PowerSupplyRecommendationsSGx524isdesignedtooperatefromaninputvoltagesupplyrangebetween8Vand40V.
Thisinputsupplyshouldbewellregulated.
Iftheinputsupplyislocatedmorethanafewinchesfromthedevice,additionalbulkcapacitancemayberequiredinadditiontotheceramicbypasscapacitors.
Atantalumcapacitorwithavalueof47μFisatypicalchoice,howeverthismayvarydependingupontheoutputpowerbeingdelivered.
SG2524,SG3524SLVS077F–APRIL1977–REVISEDJANUARY2021www.
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1LayoutGuidelinesAlwaystrytousealowEMIinductorwithaferritetypeclosedcore.
SomeexampleswouldbetoroidandencasedEcoreinductors.
OpencorecanbeusediftheyhavelowEMIcharacteristicsandarelocatedabitmoreawayfromthelowpowertracesandcomponents.
MakethepolesperpendiculartothePCBaswellifusinganopencore.
Stickcoresusuallyemitthemostunwantednoise.
10.
1.
1FeedbackTracesTrytorunthefeedbacktraceasfarfromtheinductorandnoisypowertracesaspossible.
Youwouldalsolikethefeedbacktracetobeasdirectaspossibleandsomewhatthick.
Thesetwosometimesinvolveatrade-off,butkeepingitawayfrominductorEMIandothernoisesourcesisthemorecriticalofthetwo.
RunthefeedbacktraceonthesideofthePCBoppositeoftheinductorwithagroundplaneseparatingthetwo.
10.
1.
2Input/OutputCapacitorsWhenusingalowvalueceramicinputfiltercapacitor,itshouldbelocatedasclosetotheVINpinoftheICaspossible.
ThiswilleliminateasmuchtraceinductanceeffectsaspossibleandgivetheinternalICrailacleanervoltagesupply.
Somedesignsrequiretheuseofafeed-forwardcapacitorconnectedfromtheoutputtothefeedbackpinaswell,usuallyforstabilityreasons.
InthiscaseitshouldalsobepositionedasclosetotheICaspossible.
Usingsurfacemountcapacitorsalsoreducesleadlengthandlessensthechanceofnoisecouplingintotheeffectiveantennacreatedbythrough-holecomponents.
10.
1.
3CompensationComponentsExternalcompensationcomponentsforstabilityshouldalsobeplacedclosetotheIC.
Surfacemountcomponentsarerecommendedhereaswellforthesamereasonsdiscussedforthefiltercapacitors.
Theseshouldnotbelocatedveryclosetotheinductoreither.
10.
1.
4TracesandGroundPlanesMakeallofthepower(high-current)tracesasshort,direct,andthickaspossible.
ItisgoodpracticeonastandardPCBboardtomakethetracesanabsoluteminimumof15mils(0.
381mm)perampere.
Theinductor,outputcapacitors,andoutputdiodeshouldbeasclosetoeachotherpossible.
ThishelpsreducetheEMIradiatedbythepowertracesduetothehighswitchingcurrentsthroughthem.
Thiswillalsoreduceleadinductanceandresistanceaswell,whichinturnreducesnoisespikes,ringing,andresistivelossesthatproducevoltageerrors.
ThegroundsoftheIC,inputcapacitors,outputcapacitors,andoutputdiode(ifapplicable)shouldbeconnectedclosetogetherdirectlytoagroundplane.
ItwouldalsobeagoodideatohaveagroundplaneonbothsidesofthePCB.
ThiswillreducenoiseaswellbyreducinggroundlooperrorsaswellasbyabsorbingmoreoftheEMIradiatedbytheinductor.
Formulti-layerboardswithmorethantwolayers,agroundplanecanbeusedtoseparatethepowerplane(wherethepowertracesandcomponentsare)andthesignalplane(wherethefeedbackandcompensationandcomponentsare)forimprovedperformance.
Onmulti-layerboardstheuseofviaswillberequiredtoconnecttracesanddifferentplanes.
Itisgoodpracticetouseonestandardviaper200mAofcurrentifthetracewillneedtoconductasignificantamountofcurrentfromoneplanetotheother.
Arrangethecomponentssothattheswitchingcurrentloopscurlinthesamedirection.
Duetothewayswitchingregulatorsoperate,therearetwopowerstates.
Onestatewhentheswitchisonandonewhentheswitchisoff.
Duringeachstatetherewillbeacurrentloopmadebythepowercomponentsthatarecurrentlyconducting.
Placethepowercomponentssothatduringeachofthetwostatesthecurrentloopisconductinginthesamedirection.
Thispreventsmagneticfieldreversalcausedbythetracesbetweenthetwohalf-cyclesandreducesradiatedEMI.
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2LayoutExampleFigure10-1.
LayoutExampleforSG2524SG2524,SG3524SLVS077F–APRIL1977–REVISEDJANUARY2021www.
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1RelatedLinksThetablebelowlistsquickaccesslinks.
Categoriesincludetechnicaldocuments,supportandcommunityresources,toolsandsoftware,andquickaccesstosampleorbuy.
Table11-1.
RelatedLinksPARTSPRODUCTFOLDERSAMPLE&BUYTECHNICALDOCUMENTSTOOLS&SOFTWARESUPPORT&COMMUNITYSG2524ClickhereClickhereClickhereClickhereClickhereSG3524ClickhereClickhereClickhereClickhereClickhere11.
2TrademarksAlltrademarksarethepropertyoftheirrespectiveowners.
Mechanical,Packaging,andOrderableInformationThefollowingpagesincludemechanical,packaging,andorderableinformation.
Thisinformationisthemostcurrentdataavailableforthedesignateddevices.
Thisdataissubjecttochangewithoutnoticeandrevisionofthisdocument.
Forbrowser-basedversionsofthisdatasheet,refertotheleft-handnavigation.
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com29-Jan-2021Addendum-Page1PACKAGINGINFORMATIONOrderableDeviceStatus(1)PackageTypePackageDrawingPinsPackageQtyEcoPlan(2)Leadfinish/Ballmaterial(6)MSLPeakTemp(3)OpTemp(°C)DeviceMarking(4/5)SamplesSG2524DACTIVESOICD1640RoHS&GreenNIPDAULevel-1-260C-UNLIM-25to85SG2524SG2524DRACTIVESOICD162500RoHS&GreenNIPDAULevel-1-260C-UNLIM-25to85SG2524SG2524DRE4ACTIVESOICD162500RoHS&GreenNIPDAULevel-1-260C-UNLIM-25to85SG2524SG2524DRG4ACTIVESOICD162500RoHS&GreenNIPDAULevel-1-260C-UNLIM-25to85SG2524SG2524NACTIVEPDIPN1625RoHS&GreenNIPDAUN/AforPkgType-25to85SG2524NSG3524DACTIVESOICD1640RoHS&GreenNIPDAULevel-1-260C-UNLIM0to70SG3524SG3524DRACTIVESOICD162500RoHS&GreenNIPDAULevel-1-260C-UNLIM0to70SG3524SG3524DRE4ACTIVESOICD162500RoHS&GreenNIPDAULevel-1-260C-UNLIM0to70SG3524SG3524NACTIVEPDIPN1625RoHS&GreenNIPDAUN/AforPkgType0to70SG3524NSG3524NE4ACTIVEPDIPN1625RoHS&GreenNIPDAUN/AforPkgType0to70SG3524NSG3524NSRACTIVESONS162000RoHS&GreenNIPDAULevel-1-260C-UNLIM0to70SG3524(1)Themarketingstatusvaluesaredefinedasfollows:ACTIVE:Productdevicerecommendedfornewdesigns.
LIFEBUY:TIhasannouncedthatthedevicewillbediscontinued,andalifetime-buyperiodisineffect.
NRND:Notrecommendedfornewdesigns.
Deviceisinproductiontosupportexistingcustomers,butTIdoesnotrecommendusingthispartinanewdesign.
PREVIEW:Devicehasbeenannouncedbutisnotinproduction.
Samplesmayormaynotbeavailable.
OBSOLETE:TIhasdiscontinuedtheproductionofthedevice.
(2)RoHS:TIdefines"RoHS"tomeansemiconductorproductsthatarecompliantwiththecurrentEURoHSrequirementsforall10RoHSsubstances,includingtherequirementthatRoHSsubstancedonotexceed0.
1%byweightinhomogeneousmaterials.
Wheredesignedtobesolderedathightemperatures,"RoHS"productsaresuitableforuseinspecifiedlead-freeprocesses.
TImayreferencethesetypesofproductsas"Pb-Free".
RoHSExempt:TIdefines"RoHSExempt"tomeanproductsthatcontainleadbutarecompliantwithEURoHSpursuanttoaspecificEURoHSexemption.
Green:TIdefines"Green"tomeanthecontentofChlorine(Cl)andBromine(Br)basedflameretardantsmeetJS709Blowhalogenrequirementsof<=1000ppmthreshold.
Antimonytrioxidebasedflameretardantsmustalsomeetthe<=1000ppmthresholdrequirement.
(3)MSL,PeakTemp.
-TheMoistureSensitivityLevelratingaccordingtotheJEDECindustrystandardclassifications,andpeaksoldertemperature.
PACKAGEOPTIONADDENDUMwww.
ti.
com29-Jan-2021Addendum-Page2(4)Theremaybeadditionalmarking,whichrelatestothelogo,thelottracecodeinformation,ortheenvironmentalcategoryonthedevice.
(5)MultipleDeviceMarkingswillbeinsideparentheses.
OnlyoneDeviceMarkingcontainedinparenthesesandseparatedbya"~"willappearonadevice.
IfalineisindentedthenitisacontinuationofthepreviouslineandthetwocombinedrepresenttheentireDeviceMarkingforthatdevice.
(6)Leadfinish/Ballmaterial-OrderableDevicesmayhavemultiplematerialfinishoptions.
Finishoptionsareseparatedbyaverticalruledline.
Leadfinish/Ballmaterialvaluesmaywraptotwolinesifthefinishvalueexceedsthemaximumcolumnwidth.
ImportantInformationandDisclaimer:TheinformationprovidedonthispagerepresentsTI'sknowledgeandbeliefasofthedatethatitisprovided.
TIbasesitsknowledgeandbeliefoninformationprovidedbythirdparties,andmakesnorepresentationorwarrantyastotheaccuracyofsuchinformation.
Effortsareunderwaytobetterintegrateinformationfromthirdparties.
TIhastakenandcontinuestotakereasonablestepstoproviderepresentativeandaccurateinformationbutmaynothaveconducteddestructivetestingorchemicalanalysisonincomingmaterialsandchemicals.
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TAPEANDREELINFORMATION*AlldimensionsarenominalDevicePackageTypePackageDrawingPinsSPQReelDiameter(mm)ReelWidthW1(mm)A0(mm)B0(mm)K0(mm)P1(mm)W(mm)Pin1QuadrantSG2524DRSOICD162500330.
016.
46.
510.
32.
18.
016.
0Q1SG2524DRG4SOICD162500330.
016.
46.
510.
32.
18.
016.
0Q1SG3524DRSOICD162500330.
016.
46.
510.
32.
18.
016.
0Q1SG3524NSRSONS162000330.
016.
48.
210.
52.
512.
016.
0Q1PACKAGEMATERIALSINFORMATIONwww.
ti.
com29-Jan-2021PackMaterials-Page1*AlldimensionsarenominalDevicePackageTypePackageDrawingPinsSPQLength(mm)Width(mm)Height(mm)SG2524DRSOICD162500333.
2345.
928.
6SG2524DRG4SOICD162500333.
2345.
928.
6SG3524DRSOICD162500333.
2345.
928.
6SG3524NSRSONS162000853.
0449.
035.
0PACKAGEMATERIALSINFORMATIONwww.
ti.
com29-Jan-2021PackMaterials-Page2IMPORTANTNOTICEANDDISCLAIMERTIPROVIDESTECHNICALANDRELIABILITYDATA(INCLUDINGDATASHEETS),DESIGNRESOURCES(INCLUDINGREFERENCEDESIGNS),APPLICATIONOROTHERDESIGNADVICE,WEBTOOLS,SAFETYINFORMATION,ANDOTHERRESOURCES"ASIS"ANDWITHALLFAULTS,ANDDISCLAIMSALLWARRANTIES,EXPRESSANDIMPLIED,INCLUDINGWITHOUTLIMITATIONANYIMPLIEDWARRANTIESOFMERCHANTABILITY,FITNESSFORAPARTICULARPURPOSEORNON-INFRINGEMENTOFTHIRDPARTYINTELLECTUALPROPERTYRIGHTS.
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