Malvino: MCQ in Operational Amplifiers

(Last Updated On: February 7, 2020)

This is the Multiple Choice Questions in Chapter 18: Operational Amplifiers from the book Electronic Principles 7th Edition by Albert Malvino. If you are looking for a reviewer in Electronics Engineering this will definitely help. I can assure you that this will be a great help in reviewing the book in preparation for your Board Exam. Make sure to familiarize each and every questions to increase the chance of passing the ECE Board Exam.

Topic Outline

• MCQ in Introduction to Operational Amplifiers
• MCQ in 741 Op Amp
• MCQ in Inverting Amplifier
• MCQ in Non-inverting Amplifier
• MCQ in two Op Amp Appplications
• MCQ in Linear ICs
• MCQ in Op Amp as Surface-Mount Devices

Start Practice Exam Test Questions

Choose the letter of the best answer in each questions.

1. What usually controls the open-loop cutoff frequency of an op amp?

• a. Stray-wiring capacitance
• b. Base-emitter capacitance
• c. Collector-base capacitance
• d. Compensating capacitance

2. A compensating capacitor prevents

• a. Voltage gain
• b. Oscillations
• c. Input offset current
• d. Power bandwidth

3. At the unity-gain frequency, the open-loop voltage gain is

• a. 1
• b. Amid
• c. Zero
• d. Very large

4. The cutoff frequency of an op amp equals the unity-gain frequency divided by

• a. the cutoff frequency
• b. Closed-loop voltage gain
• c. Unity
• d. Common-mode voltage gain

5. If the cutoff frequency is 15 Hz and the midband open-loop voltage gain is 1,000,000, the unity-gain frequency is

• a. 25 Hz
• b. 1 MHz
• c. 1.5 MHz
• d. 15 MHz

6. If the unity-gain frequency is 5 MHz and the midband open loop voltage gain is 200,000, the cutoff frequency is

• a. 25 Hz
• b. 1 MHz
• c. 1.5 MHz
• d. 15 MHz

7. The initial slope of a sine wave is directly proportional to

• a. Slew rate
• b. Frequency
• c. Voltage gain
• d. Capacitance

8. When the initial slope of a sine wave is greater than the slew rate,

• a. Distortion occurs
• b. Linear operation occurs
• c. Voltage gain is maximum
• d. The op amp works best

9. The power bandwidth increases when

• a. Frequency decreases
• b. Peak value decreases
• c. Initial slope decreases
• d. Voltage gain increases

10. A 741C uses

• a. Discrete resistors
• b. Inductors
• c. Active-load resistors
• d. A large coupling capacitor

11. A 741C cannot work without

• a. Discrete resistors
• b. Passive loading
• c. Dc return paths on the two bases
• d. A small coupling capacitor

12. The input impedance of a BIFET op amp is

• a. Low
• b. Medium
• c. High
• d. Extremely high

13. An LF157A is a

• a. Diff amp
• b. Source follower
• c. Bipolar op amp
• d. BIFET op amp

14. If the two supply voltages are plus and minus 15 V, the MPP value of an op amp is closest to

• a. 0
• b. +15V
• c. -15 V
• d. 30 V

15. The open-loop cutoff frequency of a 741C is controlled by

• a. A coupling capacitor
• b. The output short circuit current
• c. The power bandwidth
• d. A compensating capacitor

16. The 741C has a unity-gain frequency of

• a. 10 Hz
• b. 20 kHz
• c. 1 MHz
• d. 15 MHz

17. The unity-gain frequency equals the product of closed-loop voltage gain and the

• a. Compensating capacitance
• b. Tail current
• c. Closed-loop cutoff frequency
• d. Load resistance

18. If the unity frequency is 10 MHz and midband open-loop voltage gain is 1,000,000, then the open-loop cutoff frequency of the op amp is

• a. 10 Hz
• b. 20 Hz
• c. 50 Hz
• d. 100 Hz

19. The initial slope of a sine wave increases when

• a. Frequency decreases
• b. Peak value increases
• c. Cc increases
• d. Slew rate decreases

20. If the frequency is greater than the power bandwidth,

• a. Slew-rate distortion occurs
• b. A normal output signal occurs
• c. Output offset voltage increases
• d. Distortion may occur

21. An op amp has an open base resistor. The output voltage will be

• a. Zero
• b. Slightly different from zero
• c. Maximum positive or negative
• d. An amplified sine wave

22. An op amp has a voltage gain of 500,000. If the output voltage is 1 V, the input voltage is

• a. 2 microvolts
• b. 5 mV
• c. 10 mV
• d. 1 V

23. A 741C has supply voltages of plus and minus 15 V. If the load resistance is large, the MPP value is

• a. 0
• b. +15 V
• c. 27 V
• d. 30 V

24. Above the cutoff frequency, the voltage gain of a 741C decreases approximately

• a. 10 dB per decade
• b. 20 dB per octave
• c. 10 dB per octave
• d. 20 dB per decade

25. The voltage gain of an op amp is unity at the

• a. Cutoff frequency
• b. Unity-gain frequency
• c. Generator frequency
• d. Power bandwidth

26. When slew-rate distortion of a sine wave occurs, the output

• a. Is larger
• b. Appears triangular
• c. Is normal
• d. Has no offset

27. A 741C has

• a. A voltage gain of 100,000
• b. An input impedance of 2 Mohm
• c. An output impedance of 75 ohm
• d. All of the above

28. The closed-loop voltage gain of an inverting amplifier equals

• a. The ratio of the input resistance to the feedback resistance
• b. The open-loop voltage gain
• c. The feedback resistance divided by the input resistance
• d. The input resistance

29. The non-inverting amplifier has a

• a. Large closed-loop voltage gain
• b. Small open-loop voltage gain
• c. Large closed-loop input impedance
• d. Large closed-loop output impedance

30. The voltage follower has a

• a. Closed-loop voltage gain of unity
• b. Small open-loop voltage gain
• c. Closed-loop bandwidth of zero
• d. Large closed-loop output impedance

31. A summing amplifier can have

• a. No more than two input signals
• b. Two or more input signals
• c. A closed-loop input impedance of infinity
• d. A small open-loop voltage gain

Check your work.

Complete List of MCQ in Electronic Principles by Albert Malvino