+1 vote
in Linear Integrated Circuits by (39.8k points)
Which of the following has the same characteristic as that of non-inverting amplifier with feedback?

(a) Perfect feedback amplifier

(b) Voltage follower

(c) Perfect voltage amplifier

(d) All of the mentioned

I had been asked this question in a job interview.

The query is from Voltage Series Feedback Amplifier topic in chapter Operational Amplifier Characteristics of Linear Integrated Circuits

1 Answer

0 votes
by (6.5k points)

The correct answer is (b) Voltage follower.

Here’s why:

A non-inverting amplifier with feedback has a configuration where the input signal is applied to the non-inverting input of the operational amplifier (op-amp). The output is in phase with the input, and the voltage gain is greater than or equal to 1. When the feedback is designed to make the gain exactly equal to 1, this configuration is referred to as a voltage follower or buffer amplifier.

A voltage follower (also called a unity-gain amplifier) provides the same voltage at the output as the input, with no amplification (gain = 1), which essentially mirrors the behavior of a non-inverting amplifier with feedback when the gain is set to 1.

Let's review the options:

  • (a) Perfect feedback amplifier: This is a more general term and doesn’t specifically imply unity gain, so it doesn’t exactly match the non-inverting amplifier with feedback in this context.

  • (b) Voltage follower: This is correct. It has the same characteristic as a non-inverting amplifier with feedback when the feedback ensures a unity gain (i.e., the output equals the input).

  • (c) Perfect voltage amplifier: This generally refers to an amplifier with very high gain, which isn’t necessarily the same as a non-inverting amplifier with feedback (especially at unity gain).

  • (d) All of the mentioned: Since not all the options are correct, this is not the correct choice.

Thus, the correct answer is (b) Voltage follower.

Related questions

We welcome you to Carrieradda QnA with open heart. Our small community of enthusiastic learners are very helpful and supportive. Here on this platform you can ask questions and receive answers from other members of the community. We also monitor posted questions and answers periodically to maintain the quality and integrity of the platform. Hope you will join our beautiful community
...