苏州科技学院天平学院本科生毕业设计（论文）
密勒补偿运算放大器的设计与优化
摘 要
电子工业在如今飞速的发展，集成电路在各行各业中起到了越来越重要的作用，从而促使需求量越来越高。高速、高精度、多功能、低功耗等等的指标已经逐渐走进人们的视野。本次设计主要阐述了放大器的基本组成，简单电阻负载放大器和共源放大器以及二级密勒补偿运算放大器的设计。设计中我们采用Cadence软件在虚拟机中运行来实现电路的仿真。关注运算放大器的各项指标：开环直流增益，单位增益带宽，相位裕度，转换速率，负载电容，静态功耗，共模抑制比等等。根据提供的指标参数进行设计，最终通过改变晶体管参数和元器件参数进行分析，进而可以达到优化电路的目的。
关键词 运算放大器；电路设计；Cadence仿真；性能指标
I
苏州科技学院天平学院本科生毕业设计（论文）
The design and optimization of Miller compensation
operational amplifier
Abstract
With the rapid development of the electronics industry nowadays, IC has played an increasingly important role in all walks of life, contributing to the demand for it becoming higher and higher. This design mainly elaborated the basic components of the amplifier, a simple resistive load amplifier and a common-source amplifier, and the design of a secondary Miller compensation arithmetic amplifiers. In the design, we use Cadence software running in a virtual machine to achieve the emulation of a circuit. Concern about the indicators of the operational amplifier: DC gain, GBW, PM, SR,CL, Static power consumption, CMRR and so on. Design the circuit according to indicators and parameters provided, eventually analyzed by changing transistor parameters and component parameters and then you can achieve the purpose of optimizing the circuit.
Keywords Operational Amplifiers; Circuit Design; Emulation of Cadence ; Performance indicators
II
苏州科技学院天平学院本科生毕业设计（论文）
目 录
第1章 绪论 .......................................................... 1 1.1 引言 ............................................................................................................................. 1 1.2 设计思路、运放介绍和软件运用 ............................................................................. 1 1.2.1 运算放大器的基本设计思路 .............................................................................. 1 1.2.2 关于模拟集成运算放大器 .................................................................................. 2 1.2.3 仿真软件的介绍 .................................................................................................. 3 1.2.4 运算放大器的性能指标 ...................................................................................... 3 1.3 章节内容概述 ............................................................................................................. 4 第2章 简单的电阻负载共源放大器 ...................................... 5 2.1 电路原理分析 ............................................................................................................. 5 2.2 电路仿真过程与原理 ................................................................................................. 6 2.3 SMIC 0.18UM3.3V厚氧化栅工艺PMOS管电阻负载共源放大器影响因素仿真与分析 ................................................................................................................................. 13 2.3.1 设定电阻RD=165kΩ，L=10u不变，改变W ................................................. 13 2.3.2 设定Rds=165kΩ不变，W=5u不变，改变L .................................................. 13 2.3.3 设定W/L=40u/10u=4不变，RD=165kΩ不变，改变Vgs ............................. 14 2.3.4 设定W/L=40u/10u=4不变，改变RD的大小 .................................................. 15 2.3.5 设定RD=165kΩ不变，W/L=4不变，改变W，L的值 ................................. 15 第3章 简单共源放大器的设计 ......................................... 17 3.1 单级共源放大器的设计 ........................................................................................... 17
3.1.1 设计原理图与指标 ............................................................................................ 17 3.1.2 参数的估计 ........................................................................................................ 17 3.1.3 仿真验证 ............................................................................................................ 18 3.2 共源共栅电路 ........................................................................................................... 24 3.2.1 设计原理图与指标 ............................................................................................ 24 3.2.2 参数估计 ............................................................................................................ 25 3.3 参数比对分析 ........................................................................................................... 31 第4章 二级密勒补偿运算放大器的设计和分析 ........................... 32 4.1 电路原理和参数估计 ............................................................................................... 32 4.1.1 电路原理分析 .................................................................................................... 32 4.1.2 设计指标 ............................................................................................................ 33 4.2 电路设计与参数估算 ............................................................................................... 33 4.2.1 分配各级的增益 ................................................................................................ 33 4.2.2 确定密勒电容Cc的大小 .................................................................................. 33 4.2.3 确定各级工作电流 ............................................................................................ 34 4.2.4 确定第一级输出摆幅和静态工作点 ................................................................ 34 4.2.5 估算第一级宽长比 ............................................................................................ 35
III