Question

In an RC coupled CE amplifier, when the input frequency increases, which of these are incorrect?

(a) Reactance CSH decreases

(b) Voltage gain increases

(c) Voltage gain decreases due to shunt capacitance

(d) An RC coupled amplifier behaves like a low pass filter

This question was addressed to me in a job interview.

Question is taken from High Frequency Response in division Transistor Frequency Response of Analog Circuits

Answer 1

Correct answer is (b) Voltage gain increases

Explanation: When frequency increases, shunt reactance decreases. The voltage drop across shunt capacitance decreases and net voltage gain decrease. RC coupled amplifier acts as a low pass filter at high frequencies.