Op amps generally have a much higher value of common-mode input resistance than do discrete bipolar diff amps because
A) a current mirror is used.
B) an emitter resistor is used.
C) a compensating capacitor is used.
D) regenerative feedback is used.

Question

Quizplus · Accepted Answer

Op amps typically use a current mirror to reduce the common-mode input resistance, whereas discrete bipolar diff amps require an emitter resistor to provide adequate common-mode input resistance. Therefore, op amps generally have a higher common-mode input resistance than do discrete bipolar diff amps. The other options (B, C, and D) are not correct because they do not relate to the difference in common-mode input resistance between op amps and discrete bipolar diff amps.

Op Amps Generally Have a Much Higher Value of Common-Mode