Chapter 12, Problem 12.9P

(a) The open-loop low-frequency voltage gain of an amplifier is $A_v=$ $5\times {10}^4$ and the open-loop 3 dB frequency is $f_H=10\text{Hz}$ . If the closed-loop low-frequency gain is $A_{vf}=25,$ what is the closed-loop bandwidth? (b) The minimum closed-loop bandwidth of a feedback amplifier is to be $20\text{kHz}$ . The open-loop low-frequency voltage gain is $A_v={10}^5$ and the open-loop $3\text{dB}$ frequency is $f_H=8\text{Hz}.$ What is the maximum closed-loop voltage gain?