Simple Circuit Doubles Input Frequency

Abstract:Asimplecircuitconsistingofacomparatorandanexclusive-ORgateissufficienttodoublethefrequencyofareferencesignal.Maxim/Dallas>AppNotes>AMPLIFIERANDCOMPARATORCIRCUITSKeywords:comparators,exclusive-ORgates,XORgates,frequencydoublersAug27,2004APPLICATIONNOTE3327SimpleCircuitDoublesInputFrequencyAsimplecircuitconsistingofacomparatorandanexclusive-ORgateissufficienttodoublethefrequencyofareferencesignal.Theversatilephase-lockedloop(PLL)allowsmultiplicationofareferencefrequencywithanoperatingfrequencythatrangesfrom"DCtodaylight."APLLisoverkillforsomeapplications,however,especiallyiftheinputfrequencyneedsonlytobedoubled.Forthosecasesasimplerapproach―suchasthecircuitinFigure1―willdothejobjustaswell.Figure1.Thiscircuitdoublestheinputfrequency.Thereferen