共射极放大电路失真问题分析

Analysis of Waveform Distortion Problem in Common-emitter Amplifier

该文针对共射极放大电路实验过程中出现的输入信号u_i波形失真现象进行了阐述,分析了失真问题产生的原因,并通过Multisim进行了仿真。通过分析及仿真可知,三极管工作在饱和区时,由于发射结输入电流过大,等效电阻r_(be)近似为0,发射结为一正向导通的PN结,输入信号u_i出现截顶失真;当三极管工作在截止区时,发射结反向偏置,基极虚断,输入信号u_i不会产生明显的失真现象。

Waveform Distortion Problem of input signal ui in the Common - emitter amplifier is analyzed in this paper. In actual cases, the input waveform will be top distortion if triode operates in the saturation region, because the input current is too large and the emitter junction is deemed as a positive onset PN junction. On the other hands, when the transistor work in the cut - off area, the emission junction reverse bias, base virtual, the input signal ui will not produce significant distortion.