PWM比较器电路仿真设计

论文题目：PWM比较器电路仿真设计本科生毕业论文，绝对原创，2011年06月01日I摘要脉冲宽度调制（PWM）是利用微处理器的数字输出来对模拟电路进行控制的一种非常有效的技术，广泛应用在从测量、通信到功率控制与变换的许多领域中。脉冲宽度调制是一种模拟控制方式，其根据相应载荷的变化来调制晶体管栅极或基极的偏置，来实现开关稳压电源输出晶体管或晶体管导通时间的改变，这种方式能使电源的输出电压在工作条件变化时保持恒定，是利用微处理器的数字输出来对模拟电路进行控制的一种非常有效的技术。本文通过对PWM发展现状的了解，在掌握PWM反相器原理的基础上，比较分析了几种常见的比较器电路结构，根据PWM中对比较器的性能要求，设计了一种具有高增益和适当带宽、小的失调电压、在低功耗情况下具有较短响应时间的比较器；利用集成电路EDA设计软件，对各子模块电路进行了参数设计及仿真分析，同时进行了PWM比较器整体电路的仿真，并绘制了整体的电路版图。本文所设计PWM比较器的增益达80dB以上，总版图面积为5674um2。关键词PWM；比较器；增益；时延IIAbstractPWMisinEnglishPulseWidthModulationabbreviation,Itisuseddigitaloutputofmicroprocessortocontroloftheanalogcircuitthisisaveryeffectivetechnology,Usedforeverythingfrommeasuring,communicationstopowercontrolandconversionofmanyareas.PWMisananalogcontrolmethod,Thechangesundertheappropriateloadmodulationtransistorgateorbasebias,Toachievetheswitchingpowersupplyoutputtransistorsortransistorconductiontimechange,Thisapproachenablesmakethepowersupplyoutputvoltagechangesinworkingconditions,constant,Itisuseddigitaloutputtomicroprocessortocontroloftheanalogcircuitaveryeffectivetechnique.ThispaperisbasedonthePWMcomparatorDevelopmentofunderstanding.InthecontrolbasedonPWMprinciple,Comparativeanalysisofseveralcommoncomparatorcircuitstructure,PWMcomparatorbasedonperformancerequirements,Designasuitablebandwidth,highgainandsmalloffsetvoltage,lowpowerconsumptionincaseofashortresponsetimecomparator;UsingintegratedcircuitdesignEDAsoftware,eachofsub-modulecircuitdesignandsimulationparameters,PWMcomparatorandtheoverallsimulationofthewholecircuit.PWMcomparatordesigninthispapergainofupto100dB.Fortheoveralllayoutofthedrawing,thetotallayoutareas5674um2.KeywordsPWM;comparator;gain;delay目录摘要...........................................................................................................................................IAbstract..........................................................................................................................................II第一章引言..................................................................................................................................11.1PWM介绍........................................................................................................................11.2PWM的发展现状及应用领域........................................................................................11.3PWM技术........................................................................................................................31.4论文背景和选题意义......................................................................................................51.5本论文主要工作..............................................................................................................6第二章PWM比较器...................................................................................................................82.1几种常见比较器结构......................................................................................................82.1.1反相比较器............................................................................................................92.1.2二级比较器............................................................................................................92.1.3可驱动大电容性负载的比较器..........................................................................102.1.4迟滞比较器..........................................................................................................102.1.5离散时间比较器..................................................................................................112.2比较器参数....................................................................................................................122.2.1增益......................................................................................................................122.2.2失调电压..............................................................................................................132.2.3时延......................................................................................................................14第三章PWM比较器设计.........................................................................................................173.1设计指标........................................................................................................................173.2电流镜的设计................................................................................................................183.3前置差分放大电路设计................................................................................................203.4中间级放大器设计........................................................................................................223.5输出级设计....................................................................................................................223.6PWM比较器整体电路..................................................................................................24第四章仿真结果及分析............................................................................................................264.1电流镜的仿真及分析......................................................