TITPS2552精密电源分配方案

TITPS2552精密电源分配方案关键词：电源管理,DC/DC转换器,TPS2552/53,TPS2552-1/53-1TI公司的TPS2552/53和TPS2552-1/53-1是电源分配开关,主要用于需要精密限流或大容性负载与可能出现短路的地方.器件通过外接电阻可编程限流阈值在75mA和1.3A之间.限流精度在1.3A时为+/-6%.2us快速过流响应时间,高边MOSFET的导通电阻为85毫欧姆.内置了软起动,工作电压为2.5V到6.5V,待机电流小于1uA,可用于数字电视(DTV(,机顶盒(STB),手机和网络电话(VoIP).本文介绍了TPS2552/53和TPS2552-1/53-1的主要特性与优势,功能方框图以及评估板的电路图和所用元件列表.TheTPS2552/53andTPS2552-1/53-1power-distributionswitchesareintendedforapplicationswhereprecisioncurrentlimitingisrequiredorheavycapacitiveloadsandshortcircuitsareencountered.Thesedevicesofferaprogrammablecurrent-limitthresholdbetween75mAand1.3A(typ)viaanexternalresistor.Current-limitaccuracyastightas+/-6%canbeachievedatthehighercurrent-limitsettings.Thepower-switchriseandfalltimesarecontrolledtominimizecurrentsurgesduringturnon/off.TPS2552/53deviceslimittheoutputcurrenttoasafelevelbyswitchingintoaconstant-currentmodewhentheoutputloadexceedsthecurrent-limitthreshold.TPS2552-1/53-1devicesprovidecircuitbreakerfunctionalitybylatchingoffthepowerswitchduringovercurrentorreverse-voltagesituations.Aninternalreverse-voltagedetectioncomparatordisablesthepower-switchintheeventthattheoutputvoltageisdrivenhigherthantheinputtoprotectdevicesontheinputsideoftheswitch.TheFAULTlogicoutputassertslowduringovercurrentandreverse-voltageconditions.TPS2552/53主要特性:±6%Current-LimitAccuracyat1.3AMeetsUSBCurrent-LimitingRequirementsBackwardsCompatiblewithTPS2550/51AdjustableCurrentLimit,75mA—1300mA(typ)Constant-Current(TPS2552/53)andLatch-off(TPS2552-1/53-1)VersionsFastOvercurrentResponse-2-µS(typ)85-mΩHigh-SideMOSFET(DBVPackage)ReverseInput-OutputVoltageProtectionOperatingRange:2.5Vto6.5V1-µAMaximumStandbySupplyCurrentBuilt-inSoft-Start15kVESDProtectionperIEC61000-4-2(withExternalCapacitance)TPS2552/53主要优势:+/-6percentcurrent-limitaccuracyat1.3AMeetsUSBcurrent-limitingrequirementsAdjustablecurrentlimitfrom75mAto1,300mAConstantcurrent(TPS2552/3)andlatch-off(TPS2552-1/3-1)versionsCompatiblewithTPS2550/1Wide,2.5-Vto6.5-VinputrangeFast2-uSover-currentresponse-40degreeCto85degreeCoperatingtemperaturerangeTPS2552/53应用:USBPorts/HubsDigitalTVSet-TopBoxesMobilePhonesVOIPPhones图1.TPS2552/53功能方框图TPS2552/53评估板TheTPS2552/3DBVEVMandTPS2552/3DRVEVMareevaluationmodules(EVM)forTexasInstruments’familyofpower-distributionswitcheswithadjustablecurrent-limit.TheseEVMsoperateovera2.5-Vto6.5-Vrange.Anonboardjumpersetstheoutputcurrent-limittoeither0.5Aor1A.Testpointsprovideconvenientaccesstoallcriticalnodevoltages.ThesilkscreenoutlineonthePCBtop-sideenclosescomponentsfoundinatypicalUSBapplication.ThePCBtop-sideacceptsapower-distributionswitchinaSOT23-6package;thePCBbottomsideacceptsapower-distributionswitchinthesmallerSONpackagewithathermalpad.Theseswitcheshaveanenableinput,anovercurrentstatusoutput,andovertemperatureshutdown.图2.TPS2552/53评估板电路图AO-Electronics傲壹电子官网：中文网：评估板材料列表: