使用PWM生成模拟输出

PulseWidthModulation(PWM)modules,whichpro-ducebasicallydigitalwaveforms,canbeusedascheap

Digital-to-Analog(D/A)convertersonlyafewexternal

components.Awidevarietyofmicrocontroller

applicationsexistthatneedanalogoutputbutdonot

requirehighresolutionD/Aconverters.Somespeech

applications(talkbackunits,speechsynthesissystems

intoys,etc.)alsodonotrequirehighresolutionD/A

converters.Fortheseapplications,PulseWidth

Modulatedoutputsmaybeconvertedto

analogoutputs.AN538UsingPWMtoGenerateAnalogOutputFIGURE2:FREQUENCYSPECTRUMOFAAuthor:AmarPalacherlaPWMSIGNALMicrochipTechnologyInc.FundamentalcomponentHarmonicsPulseWidthModulation(PWM)modules,whichpro-ducebasicallydigitalwaveforms,canbeusedascheapFrequencyspectrumo