TSM1052中文资料

February2007Rev11/1515TSM1052ConstantvoltageandconstantcurrentcontrollerforbatterychargersandadaptersFeatures■Secondary-sideconstantvoltageandconstantcurrentcontrol■Verylowvoltageoperation■Verylowquiescentconsumption■High-accuracyinternalreference■Lowexternalcomponentcount■Wired-oropen-drainoutputstage■Easyfrequencycompensation■SOT23-6LmicropackageApplications■Batterychargers■AC-DCadaptersDescriptionTheTSM1052isahighlyintegratedsolutionforSMPSapplicationsrequiringadualcontrollooptoperformCV(constantvoltage)andCC(constantcurrent)regulation.TheTSM1052integratesavoltagereference,twoOp-Amps(withOR-edopen-drainoutputs),andalow-sidecurrentsensingcircuit.Thevoltagereference,alongwithoneOp-Amp,isthecoreofthevoltagecontrolloop;thecurrentsensingcircuitandtheotherOp-Ampmakeupthecurrentcontrolloop.Theexternalcomponentsneededtocompletethetwocontrolloopsare:■Aresistordividerthatsensestheoutputofthepowersupply(adapter,batterycharger)andfixesthevoltageregulationsetpointatthespecifiedvalue;■Asenseresistorthatfeedsthecurrentsensingcircuitwithavoltageproportionaltothedcoutputcurrent;thisresistordeterminesthecurrentregulationsetpointandmustbeadequatelyratedintermsofpowerdissipation;■Frequencycompensationcomponents(R-Cnetworks)forbothloops.TheTSM1052,housedinoneofthesmallestpackageavailable,isidealforspace-shrunkapplicationssuchasadaptersandchargers.SOT23-6L(topview)1.2PindescriptionVccVsenseIctrlVctrlOUTGND123654VccVsenseIctrlVccVsenseIctrlVctrlOUTGNDVctrlOUTGND123654123654123654VccVsenseIctrlVctrlOUTGND123654VccVsenseIctrlVccVsenseIctrlVctrlOUTGNDVctrlOUTGND123654123654123654Table2.PindescriptionN.NameFunction1VctrlInvertinginputofthevoltageloopOp-Amp.Thepinwillbetiedtothemid-pointofaresistordividerthatsensestheoutputvoltage.2GNDGround.Returnofthebiascurrentofthedevice.0Vreferenceforallvoltages.Thepinshouldbetiedasclosetothegroundoutputterminaloftheconverteraspossibletominimizeloadcurrenteffectonthevoltageregulationsetpoint.3OUTCommonopen-drainoutputofthetwointernalOp-Amps.Thepin,abletosinkcurrentonly,willbeconnectedtothebranchoftheoptocoupler’sphotodiodetotransmittheerrorsignaltotheprimaryside.4IctrlNon-invertinginputofthecurrentloopOp-Amp.Itwillbetieddirectlytothehot(negative)endofthecurrentsenseresistor5VsenseInvertinginputofthecurrentloopOp-Amp.Thepinwillbetiedtothecoldendofthecurrentsenseresistorthroughadecouplingresistor.6VccSupplyVoltageofthedevice.Asmallbypasscapacitor(0.1µFtyp.)toGND,locatedasclosetoIC’spinsaspossible,mightbeusefultogetacleansupplyvoltage.DescriptionTSM10524/151.3InternalschematicFigure2.Internalschematic1.4Absolutemaximumratings1.5ThermaldataVctrlGNDVsenseIctrlOUTVcc1.238V200mV+-+-+123546VctrlGNDVsenseIctrlOUTVcc1.238V200mV+-+-+1235461.21VVctrlGNDVsenseIctrlOUTVcc1.238V200mV+-+-+123546VctrlGNDVsenseIctrlOUTVcc1.238V200mV+-+-+1235461.21VTable3.AbsolutemaximumratingsSymbolPinParameterValueUnitVCC6DCsupplyvoltage-0.3to20VVOUT3Open-drainvoltage-0.3toVCCVIOUT3Maxsinkcurrent100mAV1,4,5Analoginputs-0.3to3.3VTable4.ThermaldataSymbolParameterValueUnitRthJAThermalresistance,junction-to-ambient250°C/WTOPJunctiontemperatureoperatingrange-10to85°CTjmaxMaximumjunctiontemperature150TSTGStoragetemperature-55to150TSM1052Electricalcharacteristics5/152ElectricalcharacteristicsTJ=25°CandVCC=5V,unlessotherwisespecifiedTable5.ElectricalcharacteristicsSymbolParameterTestconditionsMinTypMaxUnitDevicesupplyVCCVoltageoperatingrange1.718VICCQuiescentcurrent(Ictrl=Vsense=Vctr=0,OUT=open)150µA(1)1.Specificationreferredto-10°CTA85°C300VoltagecontrolloopOp-AmpGmvTransconductance(sinkcurrentonly)(2)2.IfthevoltageonVctrl(thenegativeinputoftheamplifier)ishigherthanthepositiveamplifierinput(Vref=1.21V),anditisincreasedby1mV,thesinkingcurrentattheoutputOUTwillbeincreasedby3.5mA.13.5S(1)2.5VrefVoltage