An op- amp has an open- loop gain of 100,000. Vsat = +/- 12 V. A differential signal voltage of 150 µVp- p is applied between the inputs. The output voltage is
A)24 Vp- p.
B)12 Vp- p.
C)12 V.
D)- 12 V.

Question

Quizplus · Accepted Answer

The open-loop gain of the op-amp is 100,000, and the input differential signal is 150 µVp-p. Multiplying the input signal by the gain gives an output signal of 150 µV * 100,000 = 15,000,000 µVp-p, or 15 Vp-p. However, since the op-amp's saturation voltage is +/- 12 V, the output voltage will be limited to the saturation levels, resulting in a maximum output voltage swing of 24 Vp-p.

An Op- Amp Has an Open- Loop Gain of 100,000