小信号放大电路的探究-毕设论文论文.doc

第页南京师范大学中北学院毕业设计（论文）（2013届）题目：小信号放大电路的探究专业：电子信息工程姓名：XXXX学号：XXXX指导教师：王兴和职称：教授填写日期：2013-04-30南京师范大学中北学院教务处制摘要目前，小信号放大电路的应用极其广泛，小到音箱、收音机等民用行业，大到卫星、火箭等军用行业。它不仅使我们的日常生活更加丰富多彩，而且对经济、国防等做出了不可磨灭的贡献。然而小信号有它自身的缺陷，由于它本身的能量较小，容易被噪声淹没或受到外界的干扰，而且对小信号放大电路设计的难处主要在高性能运算放大器。运算放大器性能的优劣决定该电路的性能。与国外相比国内对运算放大器的研究比较落后，导致对小信号放大电路的研究处于落后状态。基于OPA842ID，本设计介绍了小信号放大电路的探究与设计。该电路由五个OPA842ID组成的输入级差分放大电路、中间级电压放大电路和输出级功率放大电路完成对小信号的采集、电压放大和功率放大。同时有效的抑制或消除电路的温漂和共模信号，使放大后的信号失真度较小。设计好后的电路，使用Multisim电路仿真软件对其进行仿真。通过施加正弦小电压信号，从电路的静态工作点分析，交流分析等方面仿真，得出电路的电压增益、带宽等仿真结果，进一步验证了电路理论设计的正确性和可行性。关键词：小信号放大电路OPA842IDMultisimAbstractCurrently,theapplicationofthesmallsignalcircuitisextremelywide,smalltospeakers,radiosandothercivilianindustry,largetosatellites,rocketsandothermilitaryindustry.Itnotonlymakesourdailylifemorecolorful,butalsomadeanindeliblecontributiontotheeconomic,defenseandothers.However,thesmall-signalhasitsownflaws,becauseofitselfsmallerenergy,itiseasytodrownbythenoiseorinterferencebyoutside.Andthemaindifficultyofsmallsignalamplificationcircuitdesignishigh-performanceoperationalamplifier.Theprosandconsoftheoperationalamplifierperformancedeterminetheperformanceofthecircuit.Comparedwithforeigncountries,thedomesticoperationalamplifierisrelativelybackward,leadtothestudyofthesmall-signalamplifiercircuitinabackwardstate.BasedonOPA842ID，thisdesignintroducesasmallsignalamplificationcircuitofinquiryanddesign.ThecircuitiscomposedbyfiveOPA842IDinputleveldifferentialamplifiercircuit,theintermediatestagevoltageamplifyingcircuitandtheoutputstagepoweramplifyingcircuittocompletetheacquisitionofthesmallsignal,thevoltageamplificationandpoweramplification.Atthesametime,iteffectivelysuppressesoreliminatesthetemperaturedriftofthecircuitandthecommon-modesignal,makingtheamplifiedsignaldistortionsmaller.Aftercompletedthecircuitdesign,usingMultisimcircuitsimulationsoftwaretosimulate.Byapplyingasinusoidalvoltagesignal，fromthequiescentoperatingpointofthecircuitanalysis,ACanalysisandsoontosimulation,todrawthesimulati