封装ipower

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cnZHCS982B–JUNE2012–REVISEDMARCH2013具具有有5V和和3.
3V低低压压降降稳稳压压器器(LDO)双双路路同同步步,,降降压压控控制制器器1特特性性应应用用范范围围2输输入入电电压压范范围围::5V至至24V笔笔记记本本电电脑脑输输出出电电压压::5V和和3.
3V((可可调调范范围围±10%))平平板板电电脑脑内内置置,,100mA,,5V和和3.
3VLDO说说明明用用于于电电荷荷泵泵的的时时钟钟输输出出TPS51275,TPS51275B和TPS51275C是针对笔记±1%基基准准精精度度本系统电源解决方案的经济型,双路同步降压控制器.
自自适适应应接接通通时时间间D-CAP模模式式控控制制架架构构,,此此架架构构它提供5V和3.
3VLDO并且只需要使用极少的外部组支支持持300kHz和和355kHz频频率率设设置置件.
260kHzVCLK输出可被用于驱动一个外部电荷自自动动跳跳跃跃轻轻负负载载运运行行((TPS51275和和TPS51275C))泵,为负载开关生成栅极驱动电压而不会降低主转换器OOA轻轻负负载载运运行行(TPS51275B)的效率.
TPS51275,TPS51275B和TPS51275C支持高效,快速瞬态响应并提供一个组合电源正常信号.
内内部部0.
8ms电电压压伺伺服服器器软软启启动动自适应接通时间,D-CAP控制提供便捷且有效的运低低侧侧RDS(on)电电流流感感测测机机制制行.
此器件运行电源输入电压范围介于5V至24V之内内置置输输出出放放电电功功能能间并且支持5.
0V和3.
3V的输出电压.
用用于于开开关关的的独独立立使使能能输输入入TPS51275,TPS51275B和TPS51275C采用20引专专用用OC设设置置端端子子脚,3mmx3mm,QFN封装,额定运行温度-40°C电电源源正正常常指指示示器器至85°C.
过过压压(OVP),,欠欠压压(UVP)和和过过流流(OCP)保保护护非非锁锁存存欠欠压压闭闭锁锁(UVLO)和和过过热热(OTP)保保护护20引引脚脚,,3mmx3mm,,四四方方扁扁平平无无引引线线(QFN)(RUK)封封装装需需要要一一些些空空白白订订购购信信息息(1)可可订订购购的的使使能能跳跳跃跃模模式式常常开开模模式式-LDO封封装装输输出出电电源源数数量量器器件件号号功功能能TPS51275RUKR卷带封装3000自动跳跃VREG3TPS51275RUKT小型卷带250TPS51275BRUKR卷带封装3000EN1和EN2OOA塑料四方扁平封装TPS51275BRUKT小型卷带250VREG3和VREG5TPS51275CRUKR卷带封装3000自动跳跃TPS51275CRUKT小型卷带250(1)要获得最新的封装和订购信息,请见本文档末尾的封装选项附录,或者访问TI网站www.
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1Pleasebeawarethatanimportantnoticeconcerningavailability,standardwarranty,anduseincriticalapplicationsofTexasInstrumentssemiconductorproductsanddisclaimerstheretoappearsattheendofthisdatasheet.
2D-CAPisatrademarkofTexasInstruments.
PRODUCTIONDATAinformationiscurrentasofpublicationdate.
Copyright2012–2013,TexasInstrumentsIncorporatedProductsconformtospecificationsperthetermsoftheTexasInstrumentsstandardwarranty.
ProductionprocessingdoesnotEnglishDataSheet:SLUSB45necessarilyincludetestingofallparameters.
TPS51275,TPS51275B,TPS51275CZHCS982B–JUNE2012–REVISEDMARCH2013www.
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cnThesedeviceshavelimitedbuilt-inESDprotection.
TheleadsshouldbeshortedtogetherorthedeviceplacedinconductivefoamduringstorageorhandlingtopreventelectrostaticdamagetotheMOSgates.
TYPICALAPPLICATIONDIAGRAM(TPS51275)TYPICALAPPLICATIONDIAGRAM(TPS51275BandTPS51275C)2Copyright2012–2013,TexasInstrumentsIncorporatedTPS51275,TPS51275B,TPS51275Cwww.
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cnZHCS982B–JUNE2012–REVISEDMARCH2013ABSOLUTEMAXIMUMRATINGS(1)overoperatingfree-airtemperaturerange(unlessotherwisenoted)VALUEUNITMINMAXVBST1,VBST2–0.
332VBST1,VBST2(3)–0.
36SW1,SW2–6.
026Inputvoltage(2)VIN–0.
326VEN1,EN2–0.
36VFB1,VFB2–0.
33.
6VO1–0.
36DRVH1,DRVH2–6.
032DRVH1,DRVH2(3)–0.
36DRVH1,DRVH2(3)(pulsewidth7V,VVO1=0V,IVREG55.
5V,VVO1=0V,IVREG55V,VVO1=0V,IVREG57V,VVO1=0V,IVREG35.
5V,VVO1=0V,VVREG3VREG3outputvoltageV3.
2673.
3003.
333IVREG35.
5V,VVO1=5V,3.
2673.
3003.
333IVREG35V,VVO1=0V,IVREG3VUVLO5toVOUT=95%0.
91mstSSRAMPSoft-starttime(ramp-up)VOUT=0%toVOUT=95%,VVREG5=5V0.
78msPOWERGOODLower(risingedgeofPG-in)92.
5%95.
0%97.
5%Hysteresis5%VPGTHPGthresholdUpper(risingedgeofPG-out)107.
5%110.
0%112.
5%Hysteresis5%IPGMAXPGsinkcurrentVPGOOD=0.
5V6.
5mAIPGLKPGleakcurrentVPGOOD=5.
5V1AtPGDELPGdelayFromPGlowerthreshold(95%=typ)toPGflaghigh0.
7msCURRENTSENSINGICSCSsourcecurrentTA=25°C,VCS=0.
4V91011μATCCSCScurrenttemperaturecoefficient(1)Onthebasisof25°C4500ppm/°CVCSCSCurrentlimitsettingrange0.
22VVZCZerocrossdetectionoffsetTA=25°C–113mVLOGICTHRESHOLDVENX(ON)ENthresholdhigh-levelSMPSonlevel1.
6VVENX(OFF)ENthresholdlow-levelSMPSofflevel0.
3VIENENinputcurrentVENx=3.
3V–11AOUTPUTOVERVOLTAGEPROTECTIONVOVPOVPtripthreshold112.
5%115.
0%117.
5%tOVPDLYOVPpropagationdelayTA=25°C0.
5sOUTPUTUNDERVOLTAGEPROTECTIONVUVPUVPtripThreshold55%60%65%tUVPDLYUVPpropdelay250stUVPENDLYUVPenabledelayFromENx="Hi",VVREG5=5V1.
35msUVLOWakeup4.
58VVUVL0VINVINUVLOThresholdHysteresis0.
5VWakeup4.
384.
50VVUVLO5VREG5UVLOThresholdHysteresis0.
4VWakeup3.
15VVUVLO3VREG3UVLOThresholdHysteresis0.
15VOVERTEMPERATUREPROTECTIONShutdowntemperature155TOTPOTPthreshold(1)°CHysteresis10(1)Ensuredbydesign.
Notproductiontested.
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cnZHCS982B–JUNE2012–REVISEDMARCH2013DEVICEINFORMATIONRUKPACKAGE20PINS(TOPVIEW)PINFUNCTIONSPINNO.
TPS51275NAMEI/ODESCRIPTIONTPS51275BTPS51275CCS11OSetsthechannel1OCLtriplevel.
CS25OSetsthechannel2OCLtriplevel.
DRVH116OHigh-sidedriveroutputDRVH210OHigh-sidedriveroutputDRVL115OLow-sidedriveroutputDRVL211OLow-sidedriveroutputEN120IChannel1enable.
EN26IChannel2enable.
PGOOD7OPowergoodoutputflag.
Opendrainoutput.
PulluptoexternalrailviaaresistorSW118OSwitch-nodeconnection.
SW28OSwitch-nodeconnection.
VBST117ISupplyinputforhigh-sideMOSFET(bootstrapterminal).
ConnectcapacitorfromthispintoSWterminal.
VBST29IVCLK19OClockoutputforchargepump.
VFB12IVoltagefeedbackInputVFB24IPowerconversionvoltageinput.
Applythesamevoltageasdrainvoltageofhigh-sideMOSFETsofVIN12Ichannel1andchannel2.
VO114IOutputvoltageinput,5-Vinputforswitch-over.
VREG33O3.
3-VLDOoutput.
VREG513O5-VLDOoutput.
ThermalpadGNDterminal,soldertothegroundplaneCopyright2012–2013,TexasInstrumentsIncorporated7TPS51275,TPS51275B,TPS51275CZHCS982B–JUNE2012–REVISEDMARCH2013www.
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cnFUNCTIONALBLOCKDIAGRAM(TPS51275/B/C)8Copyright2012–2013,TexasInstrumentsIncorporatedTPS51275,TPS51275B,TPS51275Cwww.
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cnZHCS982B–JUNE2012–REVISEDMARCH2013SWITCHERCONTROLLERBLOCKDIAGRAMCopyright2012–2013,TexasInstrumentsIncorporated9TPS51275,TPS51275B,TPS51275CZHCS982B–JUNE2012–REVISEDMARCH2013www.
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cnDETAILEDDESCRIPTIONPWMOperationsThemaincontrolloopoftheswitchmodepowersupply(SMPS)isdesignedasanadaptiveon-timepulsewidthmodulation(PWM)controller.
ItsupportsaproprietaryD-CAPmode.
D-CAPmodedoesnotrequireexternalconpensationcircuitandissuitableforlowexternalcomponentcountconfigurationwhenusedwithappropriateamountofESRattheoutputcapacitor(s).
Atthebeginningofeachcycle,thesynchronoushigh-sideMOSFETisturnedon,orenterstheONstate.
ThisMOSFETisturnedoff,orentersthe'OFFstate,aftertheinternal,one-shottimerexpires.
TheMOSFETisturnedonagainwhenthefeedbackpointvoltage,VVFB,decreasedtomatchtheinternal2-Vreference.
Theinductorcurrentinformationisalsomonitoredandshouldbebelowtheovercurrentthresholdtoinitiatethisnewcycle.
Byrepeatingtheoperationinthismanner,thecontrollerregulatestheoutputvoltage.
Thesynchronouslow-side(rectifying)MOSFETisturnedonatthebeginningofeachOFFstatetomaintainaminimumofconductionloss.
Thelow-sideMOSFETisturnedoffbeforethehigh-sideMOSFETturnsonatnextswitchingcycleorwheninductorcurrentinformationdetectszerolevel.
Thisenablesseamlesstransitiontothereducedfrequencyoperationduringlight-loadconditionssothathighefficiencyismaintainedoverabroadrangeofloadcurrent.
AdaptiveOn-Time/PWMFrequencyControlBecausetheTPS51275/B/Cdoesnothaveadedicatedoscillatorforcontrollooponboard,switchingcycleiscontrolledbytheadaptiveon-timecircuit.
Theon-timeiscontrolledtomeetthetargetswitchingfrequencybyfeed-forwardingtheinputandoutputvoltageintotheon-timeone-shottimer.
Thetargetswitchingfrequencyisvariedaccordingtotheinputvoltagetoachievehigherdutyoperationforlowerinputvoltageapplication.
TheswitchingfrequencyofCH1(5-Voutput)is300kHzduringcontinuousconductionmode(CCM)operationwhenVIN=20V.
TheCH2(3.
3-Voutput)is355kHzduringCCMwhenVIN=20V.
(SeeFigure27andFigure28).
Toimproveloadtransientperformanceandloadregulationinlowerinputvoltageconditions,TPS51275/B/Ccanextendtheon-time.
Themaximumon-timeextensionofCH1is4timesforCH2is3times.
Tomaintainareasonableinductorripplecurrentduringon-timeextension,theinductorripplecurrentshouldbesettolessthanhalfoftheOCL(valley)threshold.
(SeeStep2.
ChoosetheInductor).
Theon-timeextensionfunctionprovideshighdutycycleoperationandshowsbetterDC(static)performance.
ACperformanceisdeterminedmostlybytheoutputLCfilterandresistivefactorintheloop.
LightLoadConditioninAuto-SkipOperation(TPS51275/C)TheTPS51275/Cautomaticallyreducesswitchingfrequencyduringlight-loadconditionstomaintainhighefficiency.
Thisreductionoffrequencyisachievedsmoothlyandwithoutanincreaseinoutputvoltageripple.
Amoredetaileddescriptionofthisoperationisasfollows.
Astheoutputcurrentdecreasesfromheavy-loadcondition,theinductorcurrentisalsoreducedandeventuallyapproachesvalleyzerocurrent,whichistheboundarybetweencontinuousconductionmodeanddiscontinuousconductionmode.
TherectifyingMOSFETisturnedoffwhenthiszeroinductorcurrentisdetected.
Astheloadcurrentfurtherdecreases,theconverterrunsindiscontinuousconductionmodeandittakeslongerandlongertodischargetheoutputcapacitortothelevelthatrequiresthenextONcycle.
TheONtimeismaintainedthesameasthatintheheavy-loadcondition.
Inreverse,whentheoutputcurrentincreasefromlightloadtoheavyload,theswitchingfrequencyincreasestothepresetvalueastheinductorcurrentreachestothecontinuousconduction.
ThetransitionloadpointtothelightloadoperationIOUT(LL)(i.
e.
thethresholdbetweencontinuousanddiscontinuousconductionmode)canbecalculatedasshowninEquation1.
wherefSWisthePWMswitchingfrequency(1)Switchingfrequencyversusoutputcurrentduringlight-loadconditionsisafunctionofinductance(L),inputvoltage(VIN)andoutputvoltage(VOUT),butitdecreasesalmostproportionaltotheoutputcurrentfromtheIOUT(LL).
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cnZHCS982B–JUNE2012–REVISEDMARCH2013Light-LoadConditioninOut-of-AudioOperation(TPS51275B)Out-of-Audio(OOA)light-loadmodeisauniquecontrolfeaturethatkeepstheswitchingfrequencyaboveacousticaudiblefrequenciestowardavirtualno-loadcondition.
DuringOut-of-Audiooperation,theOOAcontrolcircuitmonitorsthestatesofbothhigh-sideandlow-sideMOSFETsandforcesthemswitchingifbothMOSFETsareoffformorethan40s.
Whenbothhigh-sideandlow-sideMOSFETsareofffor40sduringalight-loadcondition,theoperationmodeischangedtoFCCM.
Thismodechangeinitiatesonecycleofthelow-sideMOSFETandthehigh-sideMOSFETturningon.
Then,bothMOSFETsstayturnedoffwaitingforanother40s.
Table1.
SKIPModeOperation(TPS51275/B/C)SKIPMODEOPERATIONTPS51275Auto-skipTPS51275BOOATPS51275CAuto-skipD-CAPModeFromsmall-signalloopanalysis,abuckconverterusingD-CAPmodecanbesimplifiedasshowninFigure1.
Figure1.
SimplifyingtheModulatorTheoutputvoltageiscomparedwithinternalreferencevoltageafterdividerresistors,R1andR2.
ThePWMcomparatordeterminesthetimingtoturnonthehigh-sideMOSFET.
ThegainandspeedofthecomparatorishighenoughtokeepthevoltageatthebeginningofeachONcyclesubstantiallyconstant.
Fortheloopstability,the0dBfrequency,0,definedinEquation2mustbelowerthan1/4oftheswitchingfrequency.
(2)As0isdeterminedsolelybytheoutputcapacitorcharacteristics,theloopstabilityduringD-CAPmodeisdeterminedbythecapacitorchemistry.
Forexample,specialtypolymercapacitorshaveoutputcapacitanceintheorderofseveralhundredmicro-FaradsandESRinrangeof10milli-ohms.
Theseyieldanf0valueontheorderof100kHzorlessandtheloopisstable.
However,ceramiccapacitorshave0atmorethan700kHz,whichisnotsuitableforthisoperationalmode.
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cnEnableandPowergoodVREG3isanalways-onregulator(TPS51275),VREG3/VREG5arealways-onregulators(TPS51275B/C),whentheinputvoltageisbeyondtheUVLOthresholditturnsON.
VREG5isturnedONwheneitherEN1orEN2enterstheONstate(TPS51275).
TheVCLKsignalinitiateswhenEN1enterstheONstate(TPS51275/B/C).
EnablestatesareshowninTable2throughTable3.
Table2.
Enabling/PGOODState(TPS51275)EN1EN2VREG5VREG3CH1(5Vout)CH2(3.
3Vout)VCLKPGOODOFFOFFOFFONOFFOFFOFFLowONOFFONONONOFFONLowOFFONONONOFFONOFFLowONONONONONONONHighTable3.
Enabling/PGOODState(TPS51275B/C)EN1EN2VREG5VREG3CH1(5Vout)CH2(3.
3Vout)VCLKPGOODOFFOFFONONOFFOFFOFFLowONOFFONONONOFFONLowOFFONONONOFFONOFFLowONONONONONONONHighFigure2.
TPS51275Timing12Copyright2012–2013,TexasInstrumentsIncorporatedTPS51275,TPS51275B,TPS51275Cwww.
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cnZHCS982B–JUNE2012–REVISEDMARCH2013Figure3.
TPS51275B/CTimingCopyright2012–2013,TexasInstrumentsIncorporated13TPS51275,TPS51275B,TPS51275CZHCS982B–JUNE2012–REVISEDMARCH2013www.
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cnSoft-StartandDischargeTheTPS51275/B/Coperatesaninternal,0.
8-ms,voltageservosoft-startforeachchannel.
WhentheENxpinbecomeshigherthantheenablethresholdvoltage,aninternalDACbeginsrampingupthereferencevoltagetothePWMcomparator.
Smoothcontroloftheoutputvoltageismaintainedduringstart-up.
WhenENxbecomeslowerthanthelowerlevelofthresholdvoltage,TPS51275/B/CdischargesoutputsusinginternalMOSFETsthroughVO1(CH1)andSW2(CH2).
VREG5/VREG3LinearRegulatorsTherearetwosetsof100-mAstandbylinearregulatorswhichoutput5Vand3.
3V,respectively.
TheVREG5pinprovidesthecurrentforthegatedrivers.
TheVREG3pinfunctionsasthemainpowersupplyfortheanalogcircuitryofthedevice.
VREG3isanAlwaysONLDOandTPS51275B/ChasAlwaysONVREG5.
(SeeTable2andTable3)Addceramiccapacitorswithavalueof1Forlarger(X5Rgradeorbetter)placedclosetotheVREG5andVREG3pinstostabilizeLDOs.
TheVREG5pinswitchoverfunctionisassertedwhenthreeconditionsarepresent:CH1internalPGOODishighCH1isnotinOCLconditionVO1voltageishigherthanVREG5-1VInthisswitchoverconditionthreethingsoccur:theinternal5-VLDOregulatorisshutofftheVREG5outputisconnectedtoVO1byinternalswitchoverMOSFETVREG3inputpassischangedfromVINtoVO1VCLKforChargePumpThe260-kHzVCLKsignalcanbeusedinthechargepumpcircuit.
TheVCLKsignalbecomesavailablewhenEN1isonstate.
TheVCLKdriverisdrivenbyVO1voltage.
InadesignthatdoesnotrequireVCLKoutput,leavetheVCLKpinopen.
OvercurrentProtectionTPS51275/B/Chascycle-by-cycleovercurrentlimitingcontrol.
TheinductorcurrentismonitoredduringtheOFFstateandthecontrollermaintainstheOFFstateduringtheinductorcurrentislargerthantheovercurrenttriplevel.
Inordertoprovidebothgoodaccuracyandcosteffectivesolution,TPS51275/B/CsupportstemperaturecompensatedMOSFETRDS(on)sensing.
TheCSxpinshouldbeconnectedtoGNDthroughtheCSvoltagesettingresistor,RCS.
TheCSxpinsourcesCScurrent(ICS)whichis10Atypicallyatroomtemperature,andtheCSxterminalvoltage(VCS=RCS*ICS)shouldbeintherangeof0.
2Vto2Voveralloperationtemperatures.
ThetriplevelissettotheOCLtripvoltage(VTRIP)asshowninEquation3.
(3)TheinductorcurrentismonitoredbythevoltagebetweenGNDpinandSWxpinsothatSWxpinshouldbeconnectedtothedrainterminalofthelow-sideMOSFETproperly.
TheCSpincurrenthasa4500ppm/°CtemperatureslopetocompensatethetemperaturedependencyoftheRDS(on).
GNDisusedasthepositivecurrentsensingnodesothatGNDshouldbeconnectedtothesourceterminalofthelow-sideMOSFET.
AsthecomparisonisdoneduringtheOFFstate,VTRIPsetsthevalleyleveloftheinductorcurrent.
Thus,theloadcurrentattheovercurrentthreshold,IOCP,canbecalculatedasshowninEquation4.
(4)Inanovercurrentcondition,thecurrenttotheloadexceedsthecurrenttotheoutputcapacitorthustheoutputvoltagetendstofalldown.
Eventually,itendsupwithcrossingtheundervoltageprotectionthresholdandshutdownbothchannels.
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cnZHCS982B–JUNE2012–REVISEDMARCH2013OutputOvervoltage/UndervoltageProtectionTPS51275/B/Cassertstheovervoltageprotection(OVP)whenVFBxvoltagereachesOVPtripthresholdlevel.
WhenanOVPeventisdetected,thecontrollerchangestheoutputtargetvoltageto0V.
ThisusuallyturnsoffDRVHandforcesDRVLtobeon.
Whentheinductorcurrentbeginstoflowthroughthelow-sideMOSFETandreachesthenegativeOCL,DRVListurnedoffandDRVHisturnedon.
Aftertheon-timeexpires,DRVHisturnedoffandDRVListurnedonagain.
ThisactionminimizestheoutputnodeundershootduetoLCresonance.
WhentheVFBxreaches0V,thedriveroutputislatchedasDRVHoff,DRVLon.
Theundervoltageprotection(UVP)latchissetwhentheVFBxvoltageremainslowerthanUVPtripthresholdvoltagefor250sorlonger.
Inthisfaultcondition,thecontrollerlatchesDRVHlowandDRVLlowanddischargestheoutputs.
UVPdetectionfunctionisenabledafter1.
35msofSMPSoperationtoensurestartup.
UndervoltageLockout(UVLO)ProtectionTPS51275/B/ChasundervoltagelockoutprotectionatVIN,VREG5andVREG3.
WheneachvoltageislowerthantheirUVLOthresholdvoltage,bothSMPSareshut-off.
Theyarenon-latchprotections.
Over-TemperatureProtectionTPS51275/B/Cfeaturesaninternaltemperaturemonitor.
Ifthetemperatureexceedsthethresholdvalue(typically155°C),TPS51275/B/CisshutoffincludingLDOs.
Thisisnon-latchprotection.
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cnExternalComponentsSelectionTheexternalcomponentsselectionisrelativelysimpleforadesignusingD-CAPmode.
Step1.
DeterminetheValueofR1andR2TherecommendedR2valueisbetween10kΩand20kΩ.
DetermineR1usingEquation5.
(5)Step2.
ChoosetheInductorTheinductancevalueshouldbedeterminedtogivetheripplecurrentofapproximately1/3ofmaximumoutputcurrentandlessthanhalfofOCL(valley)threshold.
Largerripplecurrentincreasesoutputripplevoltage,improvessignal/noiseratio,andhelpsensurestableoperation.
(6)TheinductoralsoneedstohavelowDCRtoachievegoodefficiency,aswellasenoughroomabovepeakinductorcurrentbeforesaturation.
ThepeakinductorcurrentcanbeestimatedasshowninEquation7.
(7)Step3.
ChooseOutputCapacitor(s)Organicsemiconductorcapacitor(s)orspecialtypolymercapacitor(s)arerecommended.
DetermineESRtomeetrequiredripplevoltage.
AquickapproximationisasshowninEquation8.
whereDastheduty-cyclefactortherequiredoutputripplevoltageslopeisapproximately20mVpertSW(switchingperiod)intermsofVFBterminal(8)Figure4.
RippleVoltageSlopeandJitterPerformance16Copyright2012–2013,TexasInstrumentsIncorporatedTPS51275,TPS51275B,TPS51275Cwww.
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cnZHCS982B–JUNE2012–REVISEDMARCH2013LayoutConsiderationsGoodlayoutisessentialforstablepowersupplyoperation.
FollowtheseguidelinesforanefficientPCBlayout.
PlacementPlacevoltagesettingresistorsclosetothedevicepins.
PlacebypasscapacitorsforVREG5andVREG3closetothedevicepins.
Routing(Sensitiveanalogportion)UsesmallcopperspaceforVFBx.
Thereareshortandnarrowtracestoavoidnoisecoupling.
ConnectVFBresistortracetothepositivenodeoftheoutputcapacitor.
Routinginnerlayerawayfrompowertracesisrecommended.
UseshortandwidetracefromVFBresistortoviastoGND(internalGNDplane).
Routing(Powerportion)Usewider/shortertracesofDRVLforlow-sidegatedriverstoreducestrayinductance.
UsetheparalleltracesofSWandDRVHforhigh-sideMOSFETgatedriveinasamelayeroronadjoinlayers,andkeepthemawayfromDRVL.
Usewider/shortertracesbetweenthesourceterminalofthehigh-sideMOSFETandthedrainterminalofthelow-sideMOSFETThermalpadistheGNDterminalofthisdevice.
Fiveormoreviaswith0.
33-mm(13-mils)diameterconnectedfromthethermalpadtotheinternalGNDplaneshouldbeusedtohavestrongGNDconnectionandhelpheatdissipation.
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cnTYPICALCHARACTERISTICSFigure5.
VINSupplyCurrent1vs.
JunctionTemperatureFigure6.
VINSupplyCurrent2vs.
JunctionTemperatureFigure7.
VO1SupplyCurrent1vs.
JunctionTemperatureFigure8.
VINStand-ByCurrentvs.
JunctionTemperatureFigure9.
CSSourceCurrentvs.
JunctionTemperatureFigure10.
ClockFrequencyvs.
JunctionTemperature18Copyright2012–2013,TexasInstrumentsIncorporatedTPS51275,TPS51275B,TPS51275Cwww.
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cnZHCS982B–JUNE2012–REVISEDMARCH2013TYPICALCHARACTERISTICS(continued)Figure11.
Efficiencyvs.
OutputCurrentFigure12.
Efficiencyvs.
OutputCurrentFigure13.
LoadRegulationFigure14.
LoadRegulationFigure15.
Efficiencyvs.
OutputCurrentFigure16.
Efficiencyvs.
OutputCurrentCopyright2012–2013,TexasInstrumentsIncorporated19TPS51275,TPS51275B,TPS51275CZHCS982B–JUNE2012–REVISEDMARCH2013www.
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cnTYPICALCHARACTERISTICS(continued)Figure17.
LoadRegulationFigure18.
LoadRegulationFigure19.
SwitchingFrequencyvs.
OutputCurrentFigure20.
SwitchingFrequencyvs.
OutputCurrentFigure21.
SwitchingFrequencyvs.
OutputCurrentFigure22.
SwitchingFrequencyvs.
OutputCurrent20Copyright2012–2013,TexasInstrumentsIncorporatedTPS51275,TPS51275B,TPS51275Cwww.
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cnZHCS982B–JUNE2012–REVISEDMARCH2013TYPICALCHARACTERISTICS(continued)Figure23.
Start-UpFigure24.
OutputDischargeFigure25.
5-VLoadTransientFigure26.
3.
3-VLoadTransientFigure27.
SwitchingFrequencyvs.
InputVoltageFigure28.
SwitchingFrequencyvs.
InputVoltageCopyright2012–2013,TexasInstrumentsIncorporated21TPS51275,TPS51275B,TPS51275CZHCS982B–JUNE2012–REVISEDMARCH2013www.
ti.
com.
cnAPPLICATIONDIAGRAM(TPS51275/TPS51275B/TPS51275C)Table4.
KeyExternalComponents(APPLICATIONDIAGRAM(TPS51275/TPS51275B/TPS51275C))REFERENCEFUNCTIONMANUFACTURERPARTNUMBERDESIGNATORL1OutputInductor(5-VOUT)AlpsGLMC3R303AL2OutputInductor(3.
3-VOUT)AlpsGLMC2R203AC1OutputCapacitor(5-VOUT)SANYO6TPE220MAZBx2C2OutputCapacitor(3.
3-VOUT)SANYO6TPE220MAZBx2Q1MOSFET(5-VOUT)TICSD87330Q3DQ2MOSFET(3.
3-VOUT)TICSD87330Q3D22Copyright2012–2013,TexasInstrumentsIncorporatedTPS51275,TPS51275B,TPS51275Cwww.
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com.
cnZHCS982B–JUNE2012–REVISEDMARCH2013REVISIONHISTORYChangesfromOriginal(JUNE2011)toRevisionAPageChangedtypographicalerrorinVVREG3conditioninELECTRICALCHARACTERISTICStable5AddedVVREG3specificationinELECTRICALCHARACTERISTICStable5ChangedupdatedinductorvaluesinAPPLICATIONDIAGRAM(TPS51275/TPS51275B/TPS51275C)andTable4.
.
.
.
.
.
22ChangesfromRevisionA(September2012)toRevisionBPageChanged修订版本日期,从2012年9月改为2013年3月.
同时将TPS51275B添加至器件型号1Added(TPS151275/B/C)至"特性"部分中的自动跳跃列表项1Added全新的OOA列表项至"特性"部分1Changed整个文档内的TPS51275/C至TPS51275/B/C1Changed订购信息表.
1ChangedthedevicenumberfromTPS51275CTOTPS51275B/Cintheeleccharatable2places5AddedTPS51275BtothePINNO.
column7AddedOOAsectionaftertheAuto-Skipsection11ChangedtheAPPLICATIONDIAGRAM.
22Copyright2012–2013,TexasInstrumentsIncorporated23PACKAGEOPTIONADDENDUMwww.
ti.
com10-Dec-2020Addendum-Page1PACKAGINGINFORMATIONOrderableDeviceStatus(1)PackageTypePackageDrawingPinsPackageQtyEcoPlan(2)Leadfinish/Ballmaterial(6)MSLPeakTemp(3)OpTemp(°C)DeviceMarking(4/5)SamplesHPA02239RUKRACTIVEWQFNRUK203000RoHS&GreenNIPDAULevel-2-260C-1YEAR-40to8551275TPS51275BRUKRACTIVEWQFNRUK203000RoHS&GreenNIPDAULevel-2-260C-1YEAR-40to1251275BTPS51275BRUKTACTIVEWQFNRUK20250RoHS&GreenNIPDAULevel-2-260C-1YEAR-40to1251275BTPS51275CRUKRACTIVEWQFNRUK203000RoHS&GreenNIPDAULevel-2-260C-1YEAR-40to1251275CTPS51275CRUKTACTIVEWQFNRUK20250RoHS&GreenNIPDAULevel-2-260C-1YEAR-40to1251275CTPS51275RUKRACTIVEWQFNRUK203000RoHS&GreenNIPDAULevel-2-260C-1YEAR-40to8551275TPS51275RUKTACTIVEWQFNRUK20250RoHS&GreenNIPDAULevel-2-260C-1YEAR-40to8551275(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.
(4)Theremaybeadditionalmarking,whichrelatestothelogo,thelottracecodeinformation,ortheenvironmentalcategoryonthedevice.
(5)MultipleDeviceMarkingswillbeinsideparentheses.
OnlyoneDeviceMarkingcontainedinparenthesesandseparatedbya"~"willappearonadevice.
IfalineisindentedthenitisacontinuationofthepreviouslineandthetwocombinedrepresenttheentireDeviceMarkingforthatdevice.
PACKAGEOPTIONADDENDUMwww.
ti.
com10-Dec-2020Addendum-Page2(6)Leadfinish/Ballmaterial-OrderableDevicesmayhavemultiplematerialfinishoptions.
Finishoptionsareseparatedbyaverticalruledline.
Leadfinish/Ballmaterialvaluesmaywraptotwolinesifthefinishvalueexceedsthemaximumcolumnwidth.
ImportantInformationandDisclaimer:TheinformationprovidedonthispagerepresentsTI'sknowledgeandbeliefasofthedatethatitisprovided.
TIbasesitsknowledgeandbeliefoninformationprovidedbythirdparties,andmakesnorepresentationorwarrantyastotheaccuracyofsuchinformation.
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TIhastakenandcontinuestotakereasonablestepstoproviderepresentativeandaccurateinformationbutmaynothaveconducteddestructivetestingorchemicalanalysisonincomingmaterialsandchemicals.
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TAPEANDREELINFORMATION*AlldimensionsarenominalDevicePackageTypePackageDrawingPinsSPQReelDiameter(mm)ReelWidthW1(mm)A0(mm)B0(mm)K0(mm)P1(mm)W(mm)Pin1QuadrantTPS51275BRUKRWQFNRUK203000330.
012.
43.
33.
31.
18.
012.
0Q2TPS51275BRUKTWQFNRUK20250180.
012.
43.
33.
31.
18.
012.
0Q2TPS51275CRUKRWQFNRUK203000330.
012.
43.
33.
31.
18.
012.
0Q2TPS51275CRUKTWQFNRUK20250180.
012.
43.
33.
31.
18.
012.
0Q2TPS51275RUKRWQFNRUK203000330.
012.
43.
33.
31.
18.
012.
0Q2TPS51275RUKRWQFNRUK203000330.
012.
43.
33.
31.
18.
012.
0Q2TPS51275RUKTWQFNRUK20250180.
012.
43.
33.
31.
18.
012.
0Q2TPS51275RUKTWQFNRUK20250180.
012.
43.
33.
31.
18.
012.
0Q2PACKAGEMATERIALSINFORMATIONwww.
ti.
com7-Feb-2020PackMaterials-Page1*AlldimensionsarenominalDevicePackageTypePackageDrawingPinsSPQLength(mm)Width(mm)Height(mm)TPS51275BRUKRWQFNRUK203000367.
0367.
035.
0TPS51275BRUKTWQFNRUK20250210.
0185.
035.
0TPS51275CRUKRWQFNRUK203000367.
0367.
035.
0TPS51275CRUKTWQFNRUK20250210.
0185.
035.
0TPS51275RUKRWQFNRUK203000367.
0367.
035.
0TPS51275RUKRWQFNRUK203000367.
0367.
035.
0TPS51275RUKTWQFNRUK20250210.
0185.
035.
0TPS51275RUKTWQFNRUK20250210.
0185.
035.
0PACKAGEMATERIALSINFORMATIONwww.
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