Question

4 a) List the advantages and disadvantages of using negative feedback in electronic systems b) Draw a block diagram of an amplifier with feedback, labelling clearly the open loop gain Aol and feedback fraction, ?. Show that the gain with feedback is given by Under what conditions is the closed loop gain insensitive to variations in the open loop gain? c) Identify the feedback topology of the amplifier shown in Figure Q6c and hence the amplifier type. Represent the circuit as a negative feedback system and hence estimate the appropriate gain State approximations used in your analysis.

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