引脚兼容双极型LDO的CMOS升级

Bipolarlowdropoutregulators(LDOs)havebecome

commonplaceinavarietyofportableapplications,

suchascellphones,pagersandPDAs.Their

popularitystemsfromsmallpackaging,highoutput

currentcapabilityandprecisionoutputvoltage

specifications.However,thebipolarprocess

technologyfromwhichthesedevicesarefabricated

bringsinherentdisadvantages,suchasexcessive

supplycurrent.Thisapplicationnoteoutlinesthe

advantagesofsmallgeometryCMOSLDOsover

bipolarLDOsandprovidescomparativetestdataof

keyregulatorspecificationsforapopular

pin-compatiblebipolarLDOoverMicrochip’sCMOS

LDOs.MAN766Pin-CompatibleCMOSUpgradestoBipolarLDOsAuthor:DonAlfano,DannyAlred,SUPPLYCURRENT:AbidHussainandPaulPaglia,CMOSVS.BIPOLARMicrochipTechnologyInc.Figure1(A)andFigure1(B)comparetheblockdia-gramforacommonbipolarregulatorwiththatofanINTRODUCTIONequivalentregulatorfabricatedinCMOS.Thesupplycurrenttothebipolardeviceisco