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

- MCQs in Introduction to Operational Amplifiers
- MCQs in 741 Op Amp
- MCQs in Inverting Amplifier
- MCQs in Non-inverting Amplifier
- MCQs in two Op Amp Appplications
- MCQs in Linear ICs
- MCQs 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