Op Amp(Electrical Engineering ) Questions and Answers
Question 1. The common mode gain is ___________
very high
very low
always unity
unpredictable
Explanation:-
Answer: Option B. -> very low
Question 2. Current cannot flow to ground through .
a mechanical ground
an a.c. ground
a virtual ground
an ordinary ground
Explanation:-
Answer: Option C. -> a virtual ground
Question 3. An amplifier using an opamp with slew rate SR=1v/sec has a gain of 40db.If this amplifier has to faithfully amplify sinusoidal signals from dc to 20KHz without introducing any slew-rate induced distortion, then the input signal level exceed
795mV
395mV
795mV
39.5mV
Explanation:-
Answer: Option C. -> 795mV
Question 4. When a step-input is given to an OP-amp integrator, the output will be
A ramp
A sinusoidal wave
A rectangular wave
A triangular wave with dc bias
Explanation:-
Answer: Option A. -> A ramp
Question 5. An OPAMP has a slew rate of 5 V/μS. The largest sine wave output voltage possible at a frequency of 1 MHZ is [Hint: Slew rate is defined as the max. rate of change of output voltage. Its unit is V/μS.]
$$10\pi {\text{V}}$$
$$5{\text{V}}$$
$$\frac{5}{\prod }{\text{V}}$$
$$\frac{5}{{2\prod }}{\text{V}}$$
Explanation:-
Answer: Option D. -> $$\frac{5}{{2\prod }}{\text{V}}$$
Question 6. A certain OP-amp has bias currents of 50 µA. The input offset current is
700 nA
99.3 µA
49.7 µA
none of these
Explanation:-
Answer: Option A. -> 700 nA
Question 7. The input stage of an OP-amp is usually a ___________
differential amplifier
class B push-pull amplifier
CE amplifier
swamped amplifier
Explanation:-
Answer: Option A. -> differential amplifier
Question 8. For an OP-amp having differential gain Av and common mode gain Ac the CMRR is given by
