Chegg Solutions for Microelectronic Circuits (Adel S Sedra, Kenneth C Smith) (Z-Library)_parte_102

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Step of 9 8.070P Refer Figure P7.29 in the textbook for the circuits (b). and (c). (a) Given drain current kept constant (1) = 2 From the (a), the drain current is, (1) From the given circuit (b), the drain current is, (2) Step 2 of 9 Equate equations (1) and 2 2 4L 4 on (3) over drive voltage of circuit (b) is double that the original circuit (a) proved. Step 3 of 9 The transcond is, Since drain current is kept constant, Transconductance varies inversely with the over drive voltage. Since from equation (3), Therefore, the transconductance of circuit (b) is halved that of the original circuit (a) proved. Step 4 of 9 The voltage = 2V'L The voltage gain proportional to gate length and proportional to overdrive voltage. Since, Therefore, the voltage gain of circuit (b) double that of the original circuit (a) is Step 5 of 9 (b) Since there is no change in gate width to length ratio each transistor circuit (c) have same over drive voltage as circuit (a) Therefore, over drive voltage of circuit (c) is same as that of the original circuit (a) is Step The transcond of circuit Step For the circuit (c), the small signal model shown in Figure 1. + it + v, Figure Step From Figure the output current is, (4) Write the nodal equation for the Since Substitute for equation (4). Hence, equivalent transconductance of circuit (c) is equal to for which input voltage applied. That is Hence, transcondu uctance of circuit same that of the original circuit (a). Step Voltage gain for cascaded transistor is, The overall voltage gain is proportional to gate length and inversely proportional to overdrive voltage. In circuit (c) overdrive voltage and channel length are same as that of original circuit. on Hence voltage gain of circuit (c) increased by factor of to the gain of original circuit (a).