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Fig. Q2a shows a current source constructed using M1 and RS . Assuming λ ≠ 0, (i) Analyse the circuit using small-signal approach to obtain the impedance looking into the drain of M1. (ii) Identify the advantage(s) and disadvantage(s) of the circuit. (iii) With the aid of schematic circuit diagram and graph, determine a circuit technique to mitigate the disadvantages of the circuit discussed above.

Fig. Q2a shows a current source constructed using M1 and RS . Assuming λ ≠ 0, (i) Analyse the circuit using small-signal approach to obtain the impedance looking into the drain of M1. (ii) Identify the advantage(s) and disadvantage(s) of the circuit. (iii) With the aid of schematic circuit diagram and graph, determine a circuit technique to mitigate the disadvantages of the circuit discussed above.

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Fig. Q2a shows a current source constructed using M1 and RS . Assuming λ ≠ 0, (i) Analyse the circuit using small-signal approach to obtain the impedance looking into the drain of M1. (ii) Identify the advantage(s) and disadvantage(s) of the circuit. (iii) With the aid of schematic circuit diagram and graph, determine a circuit technique to mitigate the disadvantages of the circuit discussed above.

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