# MCQs in Diode Applications

(Last Updated On: December 8, 2017)

This is the Multiple Choice Questions in Diode Applications from the book Electronic Devices and Circuit Theory 10th Edition by Robert L. Boylestad. 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.

### Online Questions and Answers Topic Outline

• MCQs in Diode Approximations
• MCQs in Series Diode Configurations with DC Inputs
• MCQs in Parallel and Series-Parallel Configurations
• MCQs in AND/OR Gates
• MCQs in Sinusoidal Inputs; Half-Wave Rectification
• MCQs in Full-Wave Rectification
• MCQs in Clippers
• MCQs in Clampers
• MCQs in Zener Diodes
• MCQs in Voltage-Multiplier Circuits

### Practice Exam Test Questions

Choose the letter of the best answer in each questions.

1. Use the information provided here to determine the value of IDQ.

• A)    0 mA
• B)    4.3 mA
• C)    5 mA
• D)    10 mA

2. In a particular problem, which mode has the highest level of IDQ?

• A)    Ideal
• B)    Approximate equivalent
• C)    Exact mode using characteristic curve
• D)    None of the above
3. Which diode(s) has (have) a zero level current and voltage drop in the ideal model?
• A)    Si
• B)    Ge
• C)    Both Si and Ge
• D)    Neither Si nor Ge

4. Determine the current level if E = 15 V and R = 3 kΩ.

• A)    0 A
• B)    4.76 mA
• C)    5 mA
• D)    5 A

5. Determine the voltage across the resistor.

• A)    0 V
• B)    0.09 V
• C)    0.2 V
• D)    0.44 V

6. Determine the value of the load resistor.

• A)    RL = 5 kΩ
• B)    RL = 5.5 kΩ
• C)    RL = 6 kΩ
• D)    None of the above

7. Determine ID.

• A)    0 mA
• B)    1.893 mA
• C)    2.036 mA
• D)    2.143 mA

8. Determine V2.

• A)    3.201 V
• B)    0 V
• C)    4.3 V
• D)    1.371 V
9. A diode is in the “_____” state if the current established by the applied sources is such that its direction matches that of the arrow in the diode symbol, and VD ≥ 0.7 V for Si and VD ≥ 0.3 V for Ge.
• A)    off
• B)    on
• C)    neutral
• D)    quiescent
10. An open circuit can have any voltage across its terminals, but the current is always _____.
• A)    5 A
• B)    0 A
• C)    1 A
• D)    ∞
11. A short circuit has a _____ drop across its terminals, and the current is limited only by the surrounding network.
• A)    5 V
• B)    0 V
• C)    1 V
• D)    ∞

12. Determine ID2.

• A)    29.40 mA
• B)    30.30 mA
• C)    14.70 mA
• D)    None of the above

13. Determine ID1.

• A)    0 mA
• B)    29.40 mA
• C)    14.70 mA
• D)    14.09 mA

14. Determine ID2.

• A)    6.061 mA
• B)    0.7 mA
• C)    3.393 mA
• D)    3.571 mA

15. Determine the current through each diode if E1 = E2 = 0 V.

• A)    4.65 mA
• B)    9.3 mA
• C)    18.6 mA
• D)    0.7 mA

16. Determine Vo if E1 = E2 = 10 V.

• A)    9.3 V
• B)    10 V
• C)    –10 V
• D)    0 V

17. What is the logic function of this circuit?

• A)    Positive logic AND gate
• B)    Positive logic OR gate
• C)    Negative logic AND gate
• D)    Negative logic OR gate

18. What is the logic function of this circuit?

• A)    Positive logic AND gate
• B)    Positive logic OR gate
• C)    Negative logic AND gate
• D)    Negative logic OR gate

19. What best describes the circuit?

• A)    Full-wave rectifier
• B)    Half-wave rectifier
• C)    Clipper
• D)    Clamper

20. Determine the peak value of the current through the load resistor.

• A)    2.325 mA
• B)    5 mA
• C)    1.25 mA
• D)    0 mA

21. Determine the average value of the current through the load resistor.

• A)    2.5 mA
• B)    0 mA
• C)    1.37 mA
• D)    1.479 mA

22. What best describes the circuit?

• A)     Full-wave rectifier
• B)    Half-wave rectifier
• C)    Clipper
• D)    Clamper

23. List the categories of clippers.

• A)    Series
• B)    Parallel
• C)    Series and parallel
• D)    None of the above

24. Determine the peak value of the output waveform.

• A)    25 V
• B)    15 V
• C)    –25 V
• D)    –15 V

25. Determine the peak for both half cycles of the output waveform.

• A)    16 V, –4 V
• B)    16 V, 4 V
• C)    –16 V, 4 V
• D)    –16 V, –4 V

26. What best describes the circuit?

• A)    Full-wave rectifier
• B)    Half-wave rectifier
• C)    Clipper
• D)    Clamper
27. Determine the total discharge time for the capacitor in a clamper having C = 0.01 µF and R = 500 kΩ.
• A)    5 ms
• B)    25 ms
• C)    2.5 ms
• D)    50 ms

28. Calculate IL and IZ.

• A)    2 mA, 0 mA
• B)    4 mA, 2 mA
• C)    2 mA, 2 mA
• D)    2 mA, 4 mA
29. With this Zener diode in its “on state,” what is the level of IZ for the maximum load resistance?

• A)    0 mA
• B)    Undefined
• C)    Equal to IRL
• D)    IZM
30. In a voltage regulator network with fixed RL and R, what element dictates the minimum level of source voltage?
• A)    VZ
• B)    IZ
• C)    IZM
• D)    None of the above

31. Which element dictates the maximum level of source voltage?

• A)    VZ
• B)    IZM
• C)    IZ
• D)    None of the above
32. What is the peak inverse voltage across each diode in a voltage doubler?
• A)    Vm
• B)    2Vm
• C)    0.5Vm
• D)    0.25Vm
33. What is the voltage measured from the negative terminal of C4 to the negative terminal of the transformer?

• A)    –10 V
• B)    –20 V
• C)    10 V
• D)    20 V
34. In a voltage-multiplier circuit, the number of diodes is directly proportional to the multiplicative voltage factor.
• A)    True
• B)    False

35. Rectifiers are commonly used in battery chargers.

• A)    True
• B)    False

### Fill-in-the-blanks Questions

1. The intersection of the load line with the characteristic curve determines the _____ of the system.
• A)    point of operation
• C)    characteristic curve
• D)    forward bias

2. The slope of the load line depends on the _____.

• A)    type of the diode used
• B)    characteristic curve
• D)    source voltage

3. The load line is defined by the _____ and a characteristic curve is defined by the _____.

• A)    quiescent point, device
• B)    device, network
• C)    network, device
• D)    None of the above

4. The quiescent point (Q-point) is defined by a(n) _____.

• A)    ac network
• B)    dc network
• C)    ac and dc network
• D)    None of the above
5. The x-intercept of the load line with the characteristic curve is determined by the _____.
• B)    diode
• C)    source voltage and the load resistor
• D)    source voltage
6. The source voltage must be _____ the voltage drop across the diode to conduct the diode.
• A)    larger than
• B)    smaller than
• C)    the same as
• D)    None of the above
7. As the load resistor increases, the slope of the dc load line and the levels of diode current _____.
• A)    increase
• B)    decrease
• C)    remain unchanged
• D)    are unpredictable
8. A germanium diode is approximated by _____ equivalent for voltages less than 0.3 V.
• A)    a short circuit
• B)    a series circuit
• C)    a parallel circuit
• D)    an open circuit
9. A diode is in the _____ state if the current established by the applied sources is such that its direction matches that of the arrow in the diode symbol and VD > 0.7 V.
• A)    off
• B)    reverse bias
• C)    on
• D)    transition
10. The combination of a short circuit in series with an open circuit always results in a(n) _____ circuit.
• A)    open
• B)    short
• C)    neither short nor open
• D)    unknown
11. The absence of the Si or Ge and VD label on a diode denotes _____ notation.
• A)    approximate model
• B)    ideal model
• C)    exact model
• D)    None of the above
12. The process of removing one-half the input signal to establish a dc level is called _____.
• A)    rectifier
• B)    full-wave rectifier
• C)   half-wave rectifier
• D)    filtering

13. The dc voltage level of a silicon diode is _____ its ideal model.

• A)    smaller than
• B)    larger than
• C)    the same as
• D)    None of the above
14. The PIV rating of the diodes in a full-wave rectifier must be larger than _____ Vm.
• A)    0.318
• B)    0.636
• C)    2
• D)    1
15. For the ideal diode the transition between states will occur at the point on the characteristic curve when VD = _____ V and ID = _____ A.
• A)    0.3, 0
• B)    0, 0
• C)    0.7, 0
• D)    0.7, 0.3

16. A clamping network must have _____.

• A)    a capacitor
• B)    a diode
• C)    a resistive element
• D)    All of the above
17. The ratio of the total swing of the output of a clamper to its input total swing is _____.
• A)    1
• B)    2
• C)    0.5
• D)    0
18. For the “off” state of a Zener diode, the voltage across the diode should be _____.
• A)    greater than VZ
• B)    zero
• C)    less than VZ but greater than zero
• D)    None of the above

19. Once the Zener diode is in the “on” state, VZ is always _____ VL.

• A)    larger than
• B)    smaller than
• C)    the same as
• D)    None of the above

20. Zener diodes are used in regulator networks to _____.

• A)    generate voltage
• B)    consume power
• C)    maintain a fixed voltage across the load resistor
21. With the Zener diode in the “on” state, increasing IL will _____ IZ and _____IR.

• A)    decrease, increase
• B)    increase, decrease
• C)    decrease, keep the same level of
• D)    increase, keep the same level of
22. A Zener diode is in a _____ impedance region in the forward bias while it has a _____ impedance region in the reverse bias.
• A)    very large, low
• B)    very large, very large
• C)    low, low
• D)    low, very large
23. In a half-wave voltage doubler, the voltage across output capacitor C2 drops across the load during the _____ half cycle and the capacitor is recharged up to _____ during the _____ half cycle.

• A)    negative, 2Vm, positive
• B)    positive, Vm, negative
• C)    positive, 2Vm, negative
• D)    negative, Vm, positive
24. The full-wave voltage doubler provides _____ filtering action than (as) the half-wave voltage doubler.
• A)    better
• B)    poorer
• C)    the same
• D)    None of the above
25. In this voltage multiplier, measuring from the top of the transformer winding will provide _____ multiples of Vm at the output, whereas measuring the output voltage from the bottom of the transformer will provide _____ multiples of the peak Vm.

• A)    odd, even
• B)    even, odd
• C)    odd, odd
• D)    even, even