Question 4 a) Derive an expression for the close loop gain of an amplifier if negative feedback is employed. b) The gain of an amplifier system is frequency dependent and is given by: A(F) = for f > fn and A(f) = and f < fi, where fn and fi are the high and low cut off frequencies and Ao is open loop gain of the amplifier. Show how the cut off frequencies are affected when negative feedback is employed in an amplifier circuit. 1+4 c) The open loop gain of an amplifier changes by 30% due to changes in parameters of the active amplifying device. If a change of gain by 2% is allowed and the gain with feedback is 10, find the minimum value of the open loop gain.

Question 4 a) Derive an expression for the close loop gain of an amplifier if negative feedback is employed. b) The gain of an amplifier system is frequency dependent and is given by: A(F) = for f > fn and A(f) = and f < fi, where fn and fi are the high and low cut off frequencies and Ao is open loop gain of the amplifier. Show how the cut off frequencies are affected when negative feedback is employed in an amplifier circuit. 1+4 c) The open loop gain of an amplifier changes by 30% due to changes in parameters of the active amplifying device. If a change of gain by 2% is allowed and the gain with feedback is 10, find the minimum value of the open loop gain.

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter12: Power System Controls

Section: Chapter Questions

Problem 12.3P

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