最近在一篇关于全差分开关电容放大器的论文中看到的一个问题,在运放的共模检测上并联了两个电容,如下图。
关于这两个电容的作用原文中有下面一段描述:
C3 and C4 are for high frequency compensation.When signal reaches very high frequency, the parasitic capacitors of M13 and M14 will significantly influence operation of OTA. With C3 and C4 dominates than those parasitic ones, this high frequency effect can be weaken considerably.