IIR数字滤波器实现
Thisapplicationnotedescribestheimplementationof
variousdigitalfiltersusingthePIC17C42,thefirst
memberofMicrochip’s2ndgenerationof8-bit
microcontrollers.ThePIC17C42isaveryhighspeed
8-bitmicrocontrollerwithaninstructioncycletimeof
250ns(@16MHzinputclock).Eventhoughthe
PIC17C42isan8-bitdevice,it’shighspeedandeffi-
cientinstructionsetallowsimplementationofdigitalfil-
tersforpracticalapplications.Traditionallydigitalfilters
havebeenimplementedusingexpensiveDigitalSignal
Processors(DSPs).InasystemtheDSPisnormallya
slaveprocessorbeingcontrolledbyeitheran8-bitor
16-bitmicrocontroller.Wheresamplingratesarenot
high(especiallyinmechanicalcontrolsystems),asin-
glechipsolutionispossibleusingthePIC17C42.AN540ImplementingIIRDigitalFiltersTHEORYOFOPERATIONAuthor:AmarPalacherlaMicrochipTechnologyInc.DigitalltersinmostcasesassumethefollowingformofrelationshipbetweentheoutputandinputINTRODUCTIONsequences.ThisapplicationnotedescribestheimplementationofvariousdigitalltersusingthePIC17C42,therstmemberofMicrochip’s2ndgenerationof8-bit