Comment on the effect of negative feedback on the gain, input and output resistance of the feedback amplifiers.Describe the gain bandwidth product term used in this context and its importance.

Comment on the effect of negative feedback on the gain, input and output resistance of the feedback amplifiers.Describe the gain bandwidth product term used in this context and its importance.
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1 Answer

Answer :

Effect of negative feedback:

1. Gain decreases with negative feedback.

2. Input resistance increases with negative feedback.

3. Output resistance decreases with negative feedback.

Explanation of significance of Gain bandwidth product

* Bandwidth measure at 3db voltage gain. As Gain and bandwidth product is always constant, and it is unity gain bandwidth.

* The gain decreases with negative feedback bandwidth increases which means it is stable output on more range of frequency.


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