# Malvino: MCQ in Negative Feedback

(Last Updated On: February 6, 2020)

This is the Multiple Choice Questions in Chapter 19: Negative Feedback 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 Four Types of Negative Feedback
• MCQs in VCVS Voltage Gain
• MCQs in ICVS Amplifier
• MCQs in VCIS Amplifier
• MCQs in ICIS Amplifier
• MCQs in Bandwidth

### Start Practice Exam Test Questions

Choose the letter of the best answer in each questions.

1. With negative feedback, the returning signal

• a. Aids the input signal
• b. Opposes the input signal
• c. Is proportional to output current
• d. Is proportional to differential voltage gain

2. How many types of negative feedback are there?

• a. One
• b. Two
• c. Three
• d. Four

3. A VCVS amplifier approximates an ideal

• a. Voltage amplifier
• b. Current-to-voltage converter
• c. Voltage-to-current converter
• d. Current amplifier

4. The voltage between the input terminals of an ideal op amp is

• a. Zero
• b. Very small
• c. Very large
• d. Equal to the input voltage

5. When an op amp is not saturated, the voltages at the non-inverting and inverting inputs are

• a. Almost equal
• b. Much different
• c. Equal to the output voltage
• d. Equal to +15 V

6. The feedback fraction B

• a. Is always less than 1
• b. Is usually greater than 1
• c. May equal 1
• d. May not equal 1

7. An ICVS amplifier has no output voltage. A possible trouble is

• a. No negative supply voltage
• b. Shorted feedback resistor
• c. No feedback voltage

8. In a VCVS amplifier, any decrease in open-loop voltage gain produces an increase in

• a. Output voltage
• b. Error voltage
• c. Feedback voltage
• d. Input voltage

9. The open-loop voltage gain equals the

• a. Gain with negative feedback
• b. Differential voltage gain of the op amp
• c. Gain when B is 1
• d. Gain at funity

10. The loop gain AOLB

• a. Is usually much smaller than 1
• b. Is usually much greater than 1
• c. May not equal 1
• d. Is between 0 and 1

11. The closed-loop input impedance with an ICVS amplifier is

• a. Usually larger than the open-loop input impedance
• b. Equal to the open-loop input impedance
• c. Sometimes less than the open-loop impedance
• d. Ideally zero

12. With an ICVS amplifier, the circuit approximates an ideal

• a. Voltage amplifier
• b. Current-to-voltage converter
• c. Voltage-to-current converter
• d. Current amplifier

13. Negative feedback reduces the

• a. Feedback fraction
• b. Distortion
• c. Input offset voltage
• d. Loop gain

14. A voltage follower has a voltage gain of

• a. Much less than 1
• b. 1
• c. More than 1
• d. A

15. The voltage between the input terminals of a real op amp is

• a. Zero
• b. Very small
• c. Very large
• d. Equal to the input voltage

16. The transresistance of an amplifier is the ratio of its

• a. Output current to input voltage
• b. Input voltage to output current
• c. Output voltage to input voltage
• d. Output voltage to input current

17. Current cannot flow to ground through

• a. A mechanical ground
• b. An ac ground
• c. A virtual ground
• d. An ordinary ground

18. In a current-to-voltage converter, the input current flows

• a. Through the input impedance of the op amp
• b. Through the feedback resistor
• c. To ground
• d. Through the load resistor

19. The input impedance of a current-to-voltage converter is

• a. Small
• b. Large
• c. Ideally zero
• d. Ideally infinite

20. The open-loop bandwidth equals

• a. funity
• b. f2(OL)
• c. funity/ACL
• d. fmax

21. The closed-loop bandwidth equals

• a. funity
• b. f2(OL)
• c. funity/ACL
• d. fmax

22. For a given op amp, which of these is constant?

• a. f2(CL)
• b. Feedback voltage
• c. ACL
• d. ACLf2(CL)

23. Negative feedback does not improve

• a. Stability of voltage gain
• b. Nonlinear distortion in later stages
• c. Output offset voltage
• d. Power bandwidth

24. An ICVS amplifier is saturated. A possible trouble is

• a. No supply voltages
• b. Open feedback resistor
• c. No input voltage

25. A VCVS amplifier has no output voltage. A possible trouble is

• b. Open feedback resistor
• c. Excessive input voltage

26. An ICIS amplifier is saturated. A possible trouble is

• b. R2 is open
• c. No input voltage

27. An ICVS amplifier has no output voltage. A possible trouble is

• a. No positive supply voltage
• b. Open feedback resistor
• c. No feedback voltage

28. The closed-loop input impedance in a VCVS amplifier is

• a. Usually larger than the open-loop input impedance
• b. Equal to the open-loop input impedance
• c. Sometimes less than the open-loop input impedance
• d. Ideally zero