通晶体管增强调节器的输出电流

摘要：一个5V线性稳压器与外部晶体管（它提供了一个额外的并行路径，负载电流）提供两倍的输出电流（150mA至300毫安）保持5V调控的同时。Maxim>AppNotes>AutomotivePower-supplycircuitsKeywords:linearregulators,passtransistorsSep24,2004APPLICATIONNOTE3333PassTransistorEnhancesRegulator'sOutputCurrentAbstract:A5Vlinearregulatorwithexternalpasstransistor(whichprovidesanadditional,parallelpathforloadcurrent)deliverstwiceasmuchoutputcurrent(150mAto300mA)whilemaintaining5Vregulation.InFigure1,the5Vlinearregulator(U1)deliversasmuchas150mAofloadcurrentwhenoperatingbyitself.Operatingwiththeexternalpasstransistorshown(Q1),thecircuitmaintains5Vregulationwhiledeliveringmorethan300mA.Figure1.Anexternalpasstransistor(Q1)morethandoublestheoutput-currentc