TheADF4002frequencysynthesizerisusedtoimplementlocaloscillatorsintheup-conversionanddown-conversionsectionsofwirelessreceiversandtransmitters.Itconsistsofalow-noisedigitalphasefrequencydetector(PFD),aprecisionchargepump,aprogrammablereferencedividerandprogrammableNdivider.The14-bitreferencecounter(Rcounter),allowsselectableREFINfrequenciesatthePFDinput.
Acompletephase-lockedloop(PLL)canbeimplementedifthesynthesizerisusedwithanexternalloopfilterandvoltagecontrolledoscillator(VCO).Inaddition,byprogrammingR&Nto1,thepartcanbeusedasastandalonePFDandchargepump.
