负反馈放大电路的稳定性分析与设计

Stability Analysis and Design of Negative Feedback Amplifier Circuit

在三级及以上的负反馈放大电路中引入深度负反馈时,首先要分析电路是否产生了自激振荡现象而不稳定,电路的稳定性将直接影响电路的放大性能。本文从电路产生自激振荡现象分析,用稳定裕度要求判断电路的状态,指出文献[1]中分析的不严谨之处,进而设计消除自激振荡现象的补偿电路。

When introducing the depth of negative feedback into negative feedback amplifier circuit with 3 or more stages,whether the circuit is instable because of the phenomenon of self-exciting oscillation must be analyzed,as the stability of the circuit will directly influence the performance of the circuit.From the analysis of self-exciting oscillation,this article uses stability margin to judge the state of circuit,points out that the analysis in literature[1]is not rigorous,and design a compensation circuit which eliminates the phenomenon of self-exciting oscillation.