LinearLTR3741大功率20A降压电源控制方案

LinearLTR3741大功率20A降压电源控制方案关键词：电源管理,DC/DC转换器Linear公司的LTR3741是大功率恒流恒压20A降压电源控制器，输入电压VIN从6V到36V，输出电压高达VIN-2V，稳压精度1.5%,稳流精度±6%，效率高达94%，主要应用在通用工业领域，超电容充电，恒压或恒流源。本文介绍LTR3741主要特性，方框图，以及典型应用电路，包括10V/20A恒压恒流降压转换器电路图，20A超电容充电器电路图，20ALED驱动器电路图以及10A单个锂离子电池充电器电路图等。LT3741-HighPower,ConstantCurrent,ConstantVoltage,Step-DownControllerTheLTR3741isafixedfrequencysynchronousstep-downDC/DCcontrollerdesignedtoaccuratelyregulatetheoutputcurrentatupto20A.Theaveragecurrent-modecontrollerwillmaintaininductorcurrentregulationoverawideoutputvoltagerangeof0Vto(VIN–2V).TheregulatedcurrentissetbyananalogvoltageontheCTRLpinsandanexternalsenseresistor.Duetoitsuniquetopology,theLT3741iscapableofsourcingandsinkingcurrent.TheregulatedvoltageandovervoltageprotectionaresetwithavoltagedividerfromtheoutputtotheFBpin.Soft-Startisprovidedtoallowagradualincreaseintheregulatedcurrentduringstartup.Theswitchingfrequencyisprogrammablefrom200kHzto1MHzthroughanexternalresistorontheRTpinorthroughtheuseoftheSYNCpinandanexternalclocksignal.AdditionalFeaturesincludeanaccurateexternalreferencevoltageforusewiththeCTRLpins,anaccurateUVLO/ENpinthatallowsforprogrammableUVLOhysteresis,andthermalshutdown.LTR3741主要特性:ControlPinProvidesAccurateControlofRegulatedOutputCurrent1.5%VoltageRegulationAccuracy±6%CurrentRegulationAccuracy6Vto36VInputVoltageRangeWideOutputVoltageRangeUpto(VIN–2V)AverageCurrentModeControl1μAShutdownCurrentUpto94%EfficiencyAdditionalPinforThermalControlofLoadCurrent4mmQFNand20-PinFEPackageThermallyEnhanced4mmxLTR3741应用:GeneralPurposeIndustrialSuper-CapChargingApplicationsNeedingExtremeShort-CircuitProtectionand/orAccurateOutputCurrentLimitConstantCurrentorConstantVoltageSource图1。LTR3741方框图图2。LTR374110V/20A恒压恒流降压转换器电路图AO-Electronics傲壹电子官网：中文网：。LTR37415V稳压输出的20A超电容充电器电路图图4。LTR374120ALED驱动器电路图图5。LTR374110A单个锂离子电池充电器电路图