Chegg Solutions for Microelectronic Circuits (Adel S Sedra, Kenneth C Smith) (Z-Library)_parte_1531

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Step 1 of 3 13.059P Refer to Figure 12.23 in the text book for the 741 input stage. Since the negative feedback increases the resistance at node Y by an amount of negative feedback, break the loop at Y and connect a resistance, between the common base connection of and ground. Write the node equation at Y. 2i = i = Since the loop gain is approximately equal to , substitute for Thus, the current is, Step 2 of 3 Determine the common-mode transconductance at the input stage, G From the circuit, the current is, Here, is the error due to mismatches in the current-mirror load Therefore, Substituting for Thus, the common-mode transconductance of the input stage is Step 3 of 3 Determine the CMRR as the ratio of the differential transconductance and the common-mode transconductance CMRR = Here, 8ml is the transconductance of Substitute for CMRR= Thus, the CMRR is The result agrees with the equation 12.95 in the text