An Amplifier with an Open-Loop Gain Of $1000 \mathrm{~V} / \mathrm{V}$

Essay

An amplifier with an open-loop gain of $1000 \mathrm{~V} / \mathrm{V}$ is connected in a feedback loop with the result that the closed-loop gain obtained is $10 \mathrm{~V} / \mathrm{V}$ .
(a) Find the value of the amount of feedback, the loop gain, and the feedback factor.
(b) If the open-loop gain varies by $\pm 10 \%$ , what is the corresponding variation of the closedloop gain?
(c) If the open-loop amplifier has 3-dB frequencies $f_{L}=1 \mathrm{kHz}$ and $f_{H}=100 \mathrm{kHz}$ , and the gain rolls off at the low and high frequency ends with a slope of $20 \mathrm{~dB} / \mathrm{decade}$ , find the $3-\mathrm{dB}$ frequencies of the closed-loop gain and sketch the Bode magnitude plot of both the open-loop and closed-loop gains (on the same axes).