Effects on negative feedback

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Effects on negative feedback:

Effects on negative feedback 1. Higher input impedance. 2. Better stabilized voltage gain. 3. Improved frequency response. 4. Lower output impedance. 5. Reduced noise. 6. More linear operation.

Effects on negative feedback:

Effects on negative feedback Reduction in Frequency Distortion For a negative-feedback amplifier having A.beta >> 1, the gain with feedback is Af = 1/beta. It follows from this that if the feedback network is purely resistive, the gain with feedback is not dependent on frequency even though the basic amplifier gain is frequency dependent. Practically, the frequency distortion arising because of varying amplifier gain with frequency is considerably reduced in a negative-voltage feedback amplifier circuit.

Effects on negative feedback:

Effects on negative feedback Reduction in Noise and Nonlinear Distortion Signal feedback tends to hold down the amount of noise signal (such as power-supply hum) and nonlinear distortion. The factor (1+ A.Beta ) reduces both input noise and resulting nonlinear distortion for considerable improvement. However, it should be noted that there is a reduction in overall gain (the price required for the improvement in circuit performance). If additional stages are used to bring the overall gain up to the level without feedback, it should be noted that the extra stage(s) might introduce as much noise back into the system as that reduced by the feedback amplifier. This

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