摘要
针对耦合电容和旁路电容在电路中的作用进行了分析和探讨,使用波特图法,可知电容耦合放大电路中耦合电容会在低频造成放大倍数十倍频20dB的下降。转折频率是fbreak=1/(2πRC),R是与电容串接的总等效电阻。同样,旁路电容也在低频造成放大倍数十倍频20dB的下降。
By Bode - plot techniques, each coupling capacitor in an RC - coupled amplifier contributes a 20 dB - per - decade in gain at low frequencies. The break frequency for each capacitor is fbreak = 1/ （2πRC）, where R is the total equivalent resistance in series with the capacitor. IdentiCally ,bypass capacitors cause the gains of common - emitter or common - source amplifiers to decline at low frequencies. The break frequency at which the gain begins to fall is given by fb^ak = 1/（ 2＇nRC）, where R is the resistance ＂seen＂ by the bypass capacitor. Finally, this paper estimates the lower half - power frequency by finding the break fre- quency for each coupling and bypass capacitors.
出处
《常州工学院学报》
2008年第4期42-44,共3页
Journal of Changzhou Institute of Technology
关键词
波特图
转折频率
下限频率
低频渐近线
Bode plot
break frequency
lower half - power frequency
low - frequency asymptote
