三极管多级音频放大器自激振荡研究与仿真

Research and Simulation of Self-excited Oscillation of Triode Multistage Audio Amplifier

从一个三极管多级音频放大器调试出现的问题出发,针对输出信号存在严重的自激振荡现象,分析电路中可能引起寄生反馈的原因,结合实际电路调试,通过Multisim软件仿真确定是由公共电源内阻引起,并给出了解决措施。充实了反馈、自激振荡内容的教学案例,为分析电路、排查故障提供了一种有效的方法。

Starting from the debugging problem of a multistage audio amplifier with triode,and aiming at the serious self-excited oscillation phenomenon of the output signal,the reason of parasitic feedback in the circuit is analyzed,and the internal resistance of the power supply is determined by the simulation software Multisim,and the solutions are given.The teaching case of feedback and self-excited oscillation is enriched,and an effective method is provided for circuit analysis and troubleshooting.