毕业设计（论文）-运放-差分电压串联负反馈的理论计算与仿真分析.doc

运放-差分电压串联负反馈的理论计算与仿真分析
摘要放大电路是电子线路中的重要组成部分,也是现代通信系统的基本组成电路,在电子电气产品中占有十分重要的位置。本文设计直接耦合方式下的运放-差分电压串联负反馈放大电路,根据多级放大增益的计算方法,采用方框图分析法,计算出基本放大器的电压增益和输出电阻的值。另外,对所构建运放-差分电路,采用微变等效电路方法,经计算节点电压,进而得到反馈放大器的电压增益,两者满足负反馈放大电路中的基本关系。同时,启用仿真软件EWB,分别对基本放大器、负反馈放大器及输出电阻仿真分析,结果与理论计算一致,说明方框图分析法在分析负反馈放大器中的应用是正确的。
关键词负反馈;运放-差分放大电路;EWB;方框图分析法
Theoretica
l Calculation and Simulation Analysis of Series Negative Feedback of Operational-differential Amplifier Voltage
Abstract Amplifying circuit not only is an important part of the electronic circuits but also is the foundation of munications system, which occupies a very important position of electrical and electronic products. In this paper, a series negative feedback amplifying circuit of the op-amp differential voltage under the direct coupled modes is designed in this paper. The voltage gain of basic amplifier and the value of the output resistance are calculated with graphic methods according to the calculating method for a multistage amplifier. Moreover, the voltage gain of a feedback amplifier is also derived by solving the node equations of small signal equivalent circuit. The results show that the basic relationship of a negative feedback amplifier circuit is satisfied in the two methods. Furthermore, the basic amplifier voltage gain, the feedback amplifier gain and the output resistance are simulated with EWB software. The results indicate that they are same as the theoretical values. The effectiveness of graphic methods applied to feedback amplifier is proved.
Keywords negative feedback; operational-differential amplifying circuit; EWB; graphic methods
目录
1引言............................................................4
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3运放-差分电压串联负反馈放大电路设计......................6
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