第3章组合逻辑电路设计.ppt

****完成下列练****其中标为红色的要用Multisim完成:52,54,55,56,58,62.(第5章)3,4,5,28,29,(续)Chapter3-Part1*OverviewPart1–DesignProcedureStepsSpecificationFormulationOptimizationTechnologyMappingBeginningHierarchicalDesignTechnologyMapping-AND,OR,andNOTtoNANDorNORVerificationManualSimulationChapter3-Part1*Overview(continued)binationalFunctionswithMultiplexersChapter3-ircuithas:AsetofmBooleaninputs,AsetofnBooleanoutputs,andnswitchingfunctions,binationstoanoutputsuchthatthecurrentoutputdependsonlyonthecurrentinputvaluesAblockdiagram:ircuitChapter3-Part1*herequiredrelationshipsbetweentheinputsandoutputs,ifnotinthespecificationApplyhierarchicaldesignifappropriateOptimizationApply2-levelandmultiple-listfortheresultingcircuitusingANDs,ORs,andinvertersChapter3-Part1*listtotheimplementationtechnologyselectedVerificationVerifythecorrectnessofthefinaldesignmanuallyorusingsimulationChapter3-Part1*DesignExampleSpecificationBCDtoExcess-3codeconverterTransformsBCDcodeforthedecimaldigitstoExcess-3codeforthedecimaldigitsBCDcodewordsfordigits0through9:4-bitpatterns0000to1001,respectivelyExcess-3codewordsfordigits0through9:4-bitpatternsconsistingof3(binary0011)addedtoeachBCDcodewordImplementation:multiple-levelcircuitNANDgates(includinginverters)Chapter3-Part1*DesignExample(continued)FormulationConversionof4-bitcodescanbemosteasilyformulatedbyatruthtableVariables-BCD:A,B,C,DVariables-Excess-3W,X,Y,ZDon’tCares-BCD1010to1111Chapter3-Part1*DesignExample(continued)Optimization2-levelusingK-mapsW=A+BC+BDX=C+D+BY=CD+Z=BCDA01324576121315148911101111XXXXXX1BCDA01324576121315148911101111XXXXXX1BCDA01324576121315148911101111XXXXXX1BCDA01324576121315**********XXXXXX11wzyxBCDBCDDChapter3-Part1*DesignExample(continued)Optimization(continued)Multiple-levelusingtransformationsW=A+BC+BD X=C+D+BY=CD+Z= G=7+10+6+0=23Performextraction,findingfactor:T1=C+DW=A+BT1X=T1+BY=CD+Z= G=2+1+4+7+6+0=19BCDBCDDBCDCDD