# The Ideal Operational Amplifiers MCQ’s

This set of Electronic Devices & Circuits Multiple Choice Questions & Answers (MCQs) focuses on “The Ideal Operational Amplifiers”.

1. Which of the following is not a property of an ideal operational amplifier?

a) Zero input impedance

b) Infinite bandwidth

c) Infinite open loop gain

d) Zero common-mode gain or conversely infinite common mode-rejection.

2. In an ideal op amp the open-loop gain is 10^{3}. The op amp is used in a feedback circuit, and the voltages appearing at two of its three signal terminals are measured as v_{2} = 0V and v_{3} = 2V where it is assumed that v_{1} and v_{2} are input terminals and v_{3} is the output terminal. The value of the differential (v_{d}) and common-mode (v_{cm})signal is

a) V_{d} = 2 mV and v_{cm} = 1 mv

b) V_{d} = 2 mV and v_{cm} = -1 mV

c) V_{d} = 2 mV and v_{cm} = 2mV

d) V_{d} = 2 mV and v_{cm} = -2mV

3. What is the minimum number of terminals required in an IC package containing four operational amplifiers (quad op amps)?

a) 12

b) 13

c) 14

d) 15

4. Consider the figure given below. Known that v_{o} = 4V and v_{i} = 2V, determine the gain for the op amp assuming that it is ideal except for the fact that it has finite gain

a) 1001

b) 2002

c) 3003

d) 4004

5. Operational amplifiers are

a) Differential input and single-ended output type amplifier

b) Single-ended input and single-ended output type amplifier

c) Single-ended input and differential output type amplifier

d) Differential input and differential output type amplifier

6. What is the minimum number of pins for a dual operational amplifier IC package?

a) 4

b) 6

c) 8

d) 10

7. Which of the following is not a terminal for the operational amplifier?

a) Inverting terminal

b) Non-inverting terminal

c) Output terminal

d) None of the mentioned

8. Express the input voltages v_{1} and v_{2} in terms of differential input (v_{d}) and common-mode input(v_{c}). Given v_{2} > v_{2}.

a) V_{d} = V_{1} – V_{2}, V_{c} = 0.5(V_{1} + V_{2})

b) V_{d} = V_{2} – V_{1}, V_{c} = V_{1} + V_{2}

c) V_{d} = V_{1} – V_{2}, V_{c} = V_{1} + V_{2}

d) V_{d} = V_{2} – V_{1}, V_{c} = 0.5(V_{1} + V_{2})

9. For an ideal operational amplifier (except for the fact that it has finite gain) one set of the value for the input voltages (v_{2} is the positive terminal v_{1} is the negative terminal) and output voltage (v_{0}) as determined experimentally is v_{1}= 2.01V, v_{2}=2.00V and v_{0}= -0.99V. Experiment was carried with different values of input and output voltages. Which of the following is not possible considering experimental error?

a) v_{1}= 1.99V, v_{2}= 2.00V, v_{0} = 1.00V

b) v_{1}= 1.00V, v_{2}= 1.00V, v_{0} = 0V

c) v_{1}= 1.00V, v_{2}= 1.10V, v_{0} = 10.1V

d) v_{1}= 0.99V, v_{2}= 2.00V, v_{0} = 1.00V

10. What are the units of slew rate?

a) Second/Volt

b) Volt/second

c) It is a ratio, no units

d) Ohm/second