摘要数字逻辑电路的分析与计算是电子课程的基础，在科研，产品开发等方面有十分重要的地位。通过根据实际功能要求，设计电路，通过真值表，转化逻辑表达式，门电路，芯片74138，设计三人表决器，实现当两人或两人以上投支持活着反对时，输出表决结果，显现多数票决断，设计的主要步骤：(1)了解三位表决器的功能及应用和设计数字电路的基本方法和步骤:记住逻辑代数的基本公式和基本定律,识别电路元,器件,掌握电路元器件的检测方法.(2)选择三位表决器的器件和芯片的型号,及芯片的引脚连线(3)合理的画出合适的电路图,且连线正确,能利用合适的门电路设计表决器和对逻辑功能的掌握.(4)运用EWB软件进行逻辑电路的模拟仿真.关键词：三位控制器,74138芯片,模拟仿真AbstractAnalysisandCalculationofdigitallogicisthebasisofelectroniccourses,hasaveryimportantroleinresearch,productdevelopmentandotherareas.Bytheactualfunctionalrequirements,designthecircuit,byatruthtable,transformationlogicexpressions,gates,chip74138,threeofthevotingmachinedesignedtoachieveinvestmentsupportoppositionalivewhentwoormorepeople,theoutputresultofthevote,showmajoritydecision,Themainstepsofthedesign:(1)tounderstandthefunctionofthethreevotingmethodsandbasicapplicationsanddigitalcircuitdesignandsteps:Rememberthebasiclogicalgebraformulasandbasiclaws,identificationcircuitelement,thedevicemasterdetectioncircuitcomponents.Pinconnections(2)selectthethreevotingdevicesandchipmodel,andchips(3)reasonabledrawtheappropriatecircuit,andthewiringiscorrect,cantakeadvantageoftherighttovoteandgatedesignforlogicfunctionstomaster.(4)theuseofEWBsoftwareforlogicsimulation.Keywords:threevoting,74138chip,simulation目录1.三位远程控制器的概述及设计意义------------------------------------------------11.1设计目的及意义-----------------------------------------------------------------------11.2功能介绍--------------------------------------------------------------------------------12.技术指标---------------------------------------------------------------------------------23.原理框图---------------------------------------------------------------------------------34.常用方法的比较------------------------------------------------------------------------44.1触发方案的选择及论证---------------------------------------------------------------44.2表决方案的论证和选择---------------------------------------------------------------44.3显示方案的论证和选择--------------