标签: 可调滤波器

Themostcommonfilterfoundinadataacquisitionsystemsignalpathisalow-passfilter.ThistypeoffilterisusuallyusedtoreduceA/DConverter(ADC)aliasingerrors.IfthereismorethanonesignalthatisappliedtotheA/Dconverterthroughamultiplexer,eachsignalsourcemayhaveitsownsetoffilterrequirements(i.e.,settlingtime,fasttransitionregion,etc.).Consequently,avarietyoffiltersmayberequiredinthecircuitpriortothemultiplexer.Usuallythesefiltersareimplementedwithoperationalamplifiers(opamps)incombinationwithfixedresistorsandcapacitors.MAN737UsingDigitalPotentiometerstoDesignLow-PassAdjustableFiltersblecornerfrequencyrangeof1:100.AnexampleoftheAuthor:BonnieC.BakerdigitalpotentiometersettingforthesedesignsisMicrochipTechnologyInc.summarizedinTables1,2and3.Thefourthscenariowillshowthesamecircuitdesign,whereallthreeINTRODUCTION……