Differentiate between positive and negative feedback.

1 Answer

Answer :

PARAMETER
POSITIVE FEEDBACK
NEGATIVE FEEDBACK
Overall phase shift
0° or 360°
180°
Feedback and input signal
Are in phase
Are out of phase
Input signal
Increases due to feedback
Decreases due to feedback
Output signal
Increases due to feedback
Decreases due to feedback
Gain
Increases due to feedback
Decreases due to feedback
Stability
Becomes poor as feedback increases
Becomes better as feedback increases
Application
Oscillators, Schmitt trigger
Amplifier, regulated power supply, bootstrapping
Noise
Increases with feedback
Decreases with feedback
Bandwidth
Decreases
Increases
Input impedance
Decreases
Increases
Output impedance
Increases
Decreases

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