差分-共射负反馈放大电路的理论计算与仿真

Theoretic Calculation and Simulation for Differential-common Emitter Amplify Circuit with Negative Feedback

构建直接耦合差分-共射电压串联负反馈放大电路,采用多级放大器的分析方法,对其进行理论计算以及仿真分析.在合理的近似处理下,静态工作点的理论计算与EWB软件对各点电位的直流仿真结果基本一致;开环和闭环放大倍数的理论计算与仿真相对误差分别为0.82%和0.28%,验证了负反馈放大电路中的基本关系式Af=A/(1+AF).

The direct coupled differential-common emitter amplify circuit with series negative feedback of voltage is designed, and the analytical method for poly-stage amplifier is adopted to theoretic calculating and simulating the circuit, With approximate dealing with the circuit on a reasonable condition, the theoretic values of static working point are almost similar to the direct current simulating results for voltage in every point of the circuit with EWB software, The relative errors between theoretic values and simulation of open loop and close loop magnification times are 0. 82% and 0.28%, and the basic relative formula Af = A/（1 ＋ AF） in negative feedback amply circuit is validated.