Question

What happens to the non-linear distortion due to the initiation of the negative feedback?

(a) level of non- linear distortion increases

(b) level of non- linear distortion decreases

(c) level of non- linear distortion remains stable

(d) level of non-linear distortion changes sinusoidal

The question was posed to me in a job interview.

I'd like to ask this question from Properties of Negative Feedback topic in division Differential and Multistage Amplifiers of Electronic Devices & Circuits

Answer 1

The correct choice is (b) level of non- linear distortion decreases

The explanation: Non- linear distortion generally happens because of essence of non linearity in the exchange qualities of transistor.

If a large amplitude signal is connected to an amplifier to extend the operation of a device beyond the linear operational range, then it also generates the non – linear distortion.

The effective input to an amplifier starts to reduce as the negative feedback is introduced; which eventually helps it to operate in the linear region.

This ability of negative feedback turns out to be beneficial in minimizing the level of non-linear distortion.