1. An atom is made up of A.

That a glue-type substance is added to

A. protons hold the material together.
B. neutrons B. That impurities are added to increase
C. electrons the resistance of the material.
D. All of the above C. The impurities are added to decrease
the resistance of the material.
2. The maximum number of electrons in each D. That all impurities are removed to get
shell of an atom is pure silicon.
A. 2.
B. 2n2 where n is the number of the shell. 8. The forward bias voltage across a
C. 4. conducting silicon diode is about
D. 8. A. 0.3V
B. 1.7V
3. An n-type semiconductor material C. -0.7V
A. is intrinsic. D. 0.7V
B. has trivalent impurity atoms added.
C. has pentavalent impurity atoms added. 9. You have an unknown type of diode in a
D. requires no doping. circuit. You measure the voltage across it
and find it to be 0.3. The diode might be
4. A diode conducts when it is forward-biased, A. a silicon diode.
and the anode is connected to the B. a germanium diode.
__________ through a limiting resistor. C. a forward-biased silicon diode.
A. positive supply D. a reverse-biased silicon diode.
B. negative supply
C. cathode 10. A reverse-biased diode has the __________
D. anode connected to the positive side of the source,
and the __________ connected to the
5. The wide end arrow on a schematic negative side of the source.
indicates the __________ of a diode. A. cathode, anode
A. ground B. cathode, base
B. direction of electron flow C. base, anode
C. cathode D. anode, cathode
D. anode
11. The movement of free electrons in a
6. The term bias in electronics usually means conductor is called
A. The value of ac voltage in the signal. A. voltage.
B. The condition of current through a pn B. current.
junction. C. recombination.
C. The value of dc voltages for the device D. equilibrium.
to operate properly. 12. A silicon diode is forward-biased. You
D. The status of the diode. measure the voltage to ground from the
7. Doping of a semiconductor material means
 anode at __________ and the voltage from B. A material doped to have some free
the cathode to ground at __________. electrons.
A. 0V, 0.3V C. A material with few free electrons.
B. 2.3V, 1.6V D. No description fits.
C. 1.6V, 2.3V
D. 0.3V, 0V 18. As the forward current through a silicon
diode increases, the internal resistance
13. There is a small-amount of current across A. increases
the barrier of a reverse-biased diode. This B. decreases
current is called C. remains the same
A. forward-bias current. D. none of the above
B. reverse-breakdown current.
C. conventional current. 19. A silicon diode measures a low value of
D. reverse leakage current. resistance with the meter leads in both
positions. The trouble, if any, is
14. The boundary between p-type material and A. the diode is open.
n-type material is called B. the diode is shorted to ground.
A. a diode. C. the diode is internally shorted.
B. a reverse-biased diode. D. the diode is working correctly.
C. a pn junction.
D. a forward-biased diode. 20. Single-element semiconductors are
characterized by atoms with __________
15. Reverse breakdown is a condition in which a valence electrons.
diode A. 3
A. is subjected to a large reverse voltage. B. 4
B. is reverse-biased and there is a small C. 5
leakage current. D. 2
C. has no current flowing at all.
D. is heated up by large amounts of 21. Effectively, how many valence electrons are
current in the forward direction. there in each atom within a silicon crystal?
A. 2
16. As the follower current through a silicon B. 4
diode increases, the voltage across the C. 8
diode D. 16
A. increases to a 0.7V maximum.
B. decreases.
C. is relatively constant. 22. What occurs when a conduction-band
D. decreases and then increases. electron loses energy and falls back into a
hole in the valence band?
17. Which is statement best describes an A. doping
insulator? B. recombination
A. A material with many electrons. C. generation
 D. none of the above 28. An ideal diode presents a(n) __________
when reversed-biased and a(n) __________
23. What types of impurity atoms are added to when forward-biased.
increases the number of conduction-band A. open, short
electrons in intrinsic silicon? B. short, open
A. bivalent C. open, open
B. octavalent D. short, short
C. pentavalent
D. trivalent 29. The most common type of a diode failure is
a(n)
24. What factor(s) do(es) the barrier potential A. open
of a pn junction depend on? B. short
A. type of semiconductive material C. resistive
B. the amount of doping D. none of the above
C. the temperature
D. all of the above 30. Every known element has
A. The same type of atoms
25. Under normal conditions a diode conducts B. The same number of atoms
current when it is C. A unique type of atom
A. reverse-biased D. Several different types of atoms
B. forward-biased
C. avalanched 31. An atom consists of
D. saturated A. One nucleus and only one electron
B. One nucleus and one or more electrons
26. For a forward-biased diode; as temperature C. Protons, electrons and neutrons
is __________ the forward current D. Answers (b) and (c)
__________ for a given value of forward
voltage. 32. The nucleus of an atom is made up of
A. decreased, increases A. Protons and neutrons
B. increased, increases B. Electrons
C. increased, decreases C. Electrons and protons
D. decreased, decreases D. Electrons and neutrons

27. For a forward-biased diode, the barrier 33. Valence electrons are
potential __________ as temperature A. In the closest orbit to the nucleus
increases. B. In the most distant orbit from the
A. decreases nucleus
B. remains constant C. In various orbits around the nucleus
C. increases D. Not associated with a particular atom
D. none of the above
34. A positive ion is formed when
 A. A valence electron breaks away from 40. The atomic number of Germanium is
the atom A. 8
B. There are more holes than electrons in B. 2
the other orbit C. 4
C. Two atoms bond together D. 32
D. An atom gains an extra valence electron
41. The valence shell in a silicon atom has the
35. The most widely used semiconductive number designation of
material in electronic devices is: A. 0
A. Germanium B. 1
B. Carbon C. 2
C. Copper D. 3
D. Silicon
42. Each atom in a silicon crystal has
36. The difference between an insulator and a A. Four valence electrons
semiconductor is B. Four conduction electrons
A. A wider energy gap between the C. Eight valence electrons, four of its own
valence band and the conduction band and four shared
B. The number of free electrons D. No valence electrons because all are
C. The atomic structure shared with other atoms
D. Answers (a), (b) and (c)
43. Electron-hole pairs are produced by
37. The energy band in which the electrons A. Recombination
exist is the B. Thermal energy
A. First band C. Ionization
B. Second band D. Doping
C. Conduction band
D. Valence band

38. In a semiconductor crystal, the atoms are

held together by
A. The interaction of valence electrons
B. Forces of attraction 44. Recombination is when
C. Covalent bonds A. An electron falls into a hole
D. Answers (a), (b) and (c) B. A positive and a negative ion bond
together
39. The atomic number of Silicon is C. A valence electron becomes a
A. 8 conduction electron
B. 2 D. A crystal is formed
C. 4
D. 14 45. The current in a semiconductor is produced
by
 A. Electrons only D. Protons
B. Holes only
C. Negative ions 51. Holes in an n-type semiconductor are
D. Both electrons and holes A. Minority carriers that are thermally
produced
46. In an intrinsic semiconductor, B. Minority carriers are produced by
A. There are no free electrons doping
B. The free electrons are thermally C. Majority carriers that are thermally
produced produced
C. There are only holes D. Majority carriers are produced by
D. There are as many electrons as there doping
are holes
E. Answers (b) and (d) 52. A pn junction is formed by
A. The recombination of electrons and
47. The process of adding an impurity to an holes
intrinsic semiconductor is B. Ionization
A. Doping C. The boundary of a p-type and an n type
B. Recombination material
C. Atomic modification D. The collision of a proton and a neutron
D. Ionization
53. The depletion region is created by
48. A trivalent impurity is added to silicone to A. Ionization
create B. Diffusion
A. Germanium C. Recombination
B. A p-type semiconductor D. Answers (a) (b) and (c)
C. An n-type semiconductor
D. A depletion region 54. The depletion region consists of
A. Nothing but minority carriers
B. Positive and negative ions
C. No majority carriers
D. Answers (b) and (c)
49. The purpose of a pentavalent impurity is to
A. Reduce the conductivity of silicon 55. The term bias means
B. Increase the number of holes A. The ratio of majority carriers to minority
C. Increase the number of free electrons carriers
D. Create minority carriers B. The amount of current across a diode
C. A dc voltage is applied to control the
50. The majority carriers in an n-type operation of a device
semiconductor are D. Neither (a), (b) nor (c)
A. Holes
B. Valence electrons 56. To forward-bias a diode,
C. Conduction electrons
 A. An external voltage is applied that is B. Conducts current
positive at the anode and negative at C. Has a high resistance
the cathode D. Drops a large voltage
B. An external voltage is applied that is
negative at the anode and positive at 61. A diode is normally operated in
the cathode A. Reverse breakdown
C. An external voltage is applied that is B. The forward-bias region
positive at the p-region and negative at C. The reverse-bias region
the n-region D. Either (b) or (c)
D. Answers (a) and (c) d. Protons
62. The dynamic resistance can be important
57. When a diode is forward-biased, when the diode is
A. The only current is hole current A. Reverse-biased
B. The only current is electron current B. Forward-biased
C. The only current is produced by C. In reverse breakdowns
majority carriers D. Unbiased
D. The current is produced by both holes
and electrons 63. The V-I curve for a diode means,
A. The voltage across the diode for a given
58. Although current is blocked to reverse bias, current
A. There is some current due to majority B. The amount of current for a given bias
carriers voltage
B. There is a very small current due to C. The power dissipation
minority carriers D. None of these
C. There is an avalanche current
64. Ideally, a diode can be represented by a
A. Voltage source
B. Resistance
C. Switch
D. All of these

59. For a silicone diode, the value of the 65. In the practical diode model,
forward-bias voltage typically A. The barrier potential is taken into
A. Must be greater than 0.3 V account
B. Must be greater than 0.7 V B. The forward dynamic resistance is taken
C. Depends on the width of the depletion into account
regions C. None of these
D. Depends on the concentration of D. Both (a) and (b)
majority carriers
66. In the complete diode model,
60. When forward-biased, a diode, A. The barrier potential is taken into
A. Blocks current account
 B. The forward dynamic resistance is taken
into account
C. The reverse resistance is taken into
account
D. All of these

67. When a silicon diode is working properly in

forward bias, a DMM in the diode test
position will indicate
A. 0 V
B. OL
C. Approximately 0.7 V
D. Approximately 0.3 V

68. When a silicon diode is open, a DMM will

generally indicate
A. 0 V
B. OL
C. Approximately 0.7 V
D. Approximately 0.3 V

1. If the ac supply is 60 Hz, what will be

the ripple frequency out of the half-
wave rectifier?
A. 30 Hz
B. 50 Hz
C. 60 Hz
D. 120 Hz

2. If the ac supply is 50 Hz, what will be

the ripple frequency out of the full-
wave rectifier?
A. 50 Hz
B. 60 Hz
 C. 100 Hz
D. 120 Hz 7. The probable trouble, if any, indicated
by these voltages is
3. A silicon diode in a half-wave rectifier
has a barrier potential of 0.7V. This has
the effect of
A. reducing the peak output voltage by
0.7V.
B. increasing the peak output voltage A. one of the diodes is open.
by 0.7V. B. a diode is shorted.
C. reducing the peak input voltage C. an open transformer secondary.
0.7V. D. the filter capacitor is shorted.
D. no effect.
8. If the voltmeter across the transformer
4. In a regulated supply, what term reads 0V, the probable trouble, if any,
describes how much change occurs in would be
the output voltage for a given change in
the input voltage?
A. Load regulation
B. Voltage regulator
C. Line regulation
D. Ripple voltage A. one of the diodes is open
B. a diode is shorted.
C. an open transformer secondary.
D. the filter capacitor is shorted.

9. Which oscilloscope trace indicates the

5. In a regulated supply, what term output from a properly operating half-
describes how much change occurs in wave rectifier without a filter?
the output voltage over a certain range Assume that each scope has the same
of load current values, from minimum settings
to maximum current? A. a
A. Line regulation B. b
B. Voltage regulator C. c
C. Current regulator D. d
D. Load regulation

6. PIV is which of the following?

A. Peak input voltage
B. Peak inverse voltage
C. Peak immediate voltage
D. Positive input voltage
 10. Which oscilloscope trace indicates the
output from a properly operating full- 12. The oscilloscope trace in (b) could
wave rectifier with a filter? represent the output from

A. a
B. b
C. c
D. d

A. a full-
wave rectifier (no filter) with an
B. a normal half-wave power supply
C. a filtered full-wave rectifier with an
open diode.
D. a full-wave rectifier with a shorted
diode.
11. Which oscilloscope indicates the output
13. Refer to the circuit FIGURE 1 (a). Refer
from a full-wave filtered rectifier with as
to the output waveforms shown in
open diode?
FIGURE 2 and select the correct
A. a
approximate output waveform.
B. B
C. C
D. D

E2
\2
 A. a
B. b A. a
C. c B. b
D. d C. c
D. d

14. Refer to the circuit in FIGURE 1 (b).

Refer to the output waveforms in 16. Refer to the circuit in FIGURE 1 (d).
FIGURE 2 and select the correct Refer to the output waveforms in
approximate output waveform. FIGURE 2 and select the correct
approximate output waveform.

FIGURE 2
FIGURE 2
1\2\\2
1\2\\2
A. a
B. b A. a
C. c B. b
FIGURE 1
FIGURE 1 D. d C. c
D. d
17. Which diode arrangement will supply a
15. Refer to the circuit in FIGURE 1 (c). negative output voltage?
Refer to the output waveforms in
FIGURE 2 and select the correct
approximate output waveform.

FIGURE 2
1\2\\2

FIGURE 1
 A. a C. equal to
B. b D. none of the above
C. c
D. d 21. Each diode in a center-tapped full wave
rectifier is __________-biased and
conducts for __________ of the input
cycle.
A. forward, 90°
B. reverse, 180°
C. forward, 180°
D. reverse, 90°

18. Which diode arrangement will supply 22. The output frequency of a full-wave
positive output voltage? rectifier is __________ the input
frequency
A. a A. one-half
B. b B. equal to
C. c C. twice
D. d D. one-quarter

23. What is the PIV for each diode in a full-

wave center-tapped rectifier? Note:
Vp(out) = peak output voltage.
A. Vp(out) - 0.7 V
B. Vp(out) + 0.7V
C. 2Vp(out) - 0.7V
D. 2Vp(out) + 0.7V

19. A silicon diode has a voltage to ground

24. In the operation of a half-wave rectifier
of -117 V from the anode. The voltage
with a capacitor-input filter, ripple
to ground from the cathode is -117.7.
factor can be lowered by ____ the value
the diode is
of the filter capacitor or ____ the load
A. open.
resistors.
B. shorted.
A. decreasing, decreasing
C. forward-biased.
B. decreasing, increasing
D. reverse-biased.
C. increasing, decreasing
D. increasing, increasing
20. The output frequency of a half-wave
25. What type of diode circuit is used to clip
rectifier is __________ the input
off portions of signal voltages above or
frequency.
below certain levels?
A. one-half
A. clipper or limiter
B. twice
B. clamper
 C. IC voltage regulator
D. none of the above 31. The peak value of the input to a half-
wave rectifier is 10 V, the diode must be
26. What type of diode circuit is used to able to withstand a reverse voltage of
add or restore a dc level to an electrical A. 10 V
signal B. 5 V
A. clipper or limiter C. 20 V
B. clamper D. 3.18 V
C. IC voltage regulator
D. none of the above 32. When a 60 Hz sinusoidal voltage is
applied to the input of a full-wave
27. what is the VRRM (PIV rating) for the rectifier, the output frequency is
1N4001 rectifier diode? A. 120 Hz
A. 50 V B. 60 Hz
B. 100 V C. 240 Hz
C. 200 V D. 0 Hz
D. 400 V

28. How many terminals do the 7800 series 33. The total secondary voltage in a center
fixed positive voltage regulators have? tapped full-wave rectifier is 125 V rms.
A. 2 Neglecting the diode drop, the rms
B. 3 output voltage is
C. 4 A. 125 V
D. 5 B. 177 V
C. 100 V
D. 62.5 V
29. When a 60Hz sinusoidal voltage is
applied to the input of a half-wave
rectifier, the output frequency is:
A. 120Hz
B. 30Hz
C. 60Hz
D. 0Hz
34. When the peak output voltage is 100 V,
the PIV for each diode in a center-
30. The peak value of the input to a half- tapped full-wave rectifier is (neglecting
wave rectifier is 10 V. The approximate the diode drop)
peak value of the output is: A. 100 V
A. 10 V B. 200 V
B. 3.18 V C. 141 V
C. 10.7 V D. 50 V
D. 9.3 V
35. The ideal dc output voltage of a
capacitor input filter is equal to 39. In a rectifier circuit, if the secondary
A. The peak value of the rectified winding in the transformer opens, the
voltage output is
B. The average value of the rectified A. 0 V
voltage B. 120 V
C. The rms value of the rectified C. Less than it should be
voltage D. Unaffected

36. If the load resistance of a capacitor- 40. If one of the diodes in a bridge full-wave
filtered full-wave rectifier is reduced, rectifier opens, the output is
the ripple voltage A. 0 V
A. Increases B. One-fourth the amplitude of the
B. Decreases input voltage
C. Is not affected C. A half-wave rectified voltage
D. Has a different frequency D. A 120 Hz voltage

37. Line regulation is determined by: 41. If you are checking a 60Hz full-wave
A. Load current bridge rectifier and observe that the
B. Zener current and load current output has a 60 Hz ripple,
C. Changes in load resistance and A. The circuit is working properly
output voltage B. There is an open diode
D. Changes in output voltage and input C. The transformer secondary is
voltage shorted
D. The filter capacitor is leaky

1. The process of emitting photons

from a semiconductive material is
called
38. Load regulation is determined by:
A. photoluminescence
A. Changes in load current and input
B. gallium arsenide
voltage
C. electroluminescence
B. Changes in load current and output
D. gallium phosphide
voltage
C. Changes in load resistance and
2. The normal operating region for a
input voltage
zener diode is the
D. Changes in zener current and load
A. forward-bias region.
current
 B. reverse-bias region.
C. zero-crossing region.
D. reverse-breakdown region.

3. Schottky diodes are also known as A. remain the same, increase

A. PIN diodes. B. decrease, remain the same
B. how carrier diodes. C. increase, remain the same
C. step-recovery diodes. D. remain the same, decrease
D. tunnel diodes.
8. If VIN attempts to increase, VR will
4. A laser diode normally emits
A. coherent light.
B. monochromatic light.
C. coherent and monochromatic
light.
A. increase.
D. neither coherent nor
B. decrease.
monochromatic light.
C. remain the same.
D. none of the above.
5. An 8.2 V has a resistance of 5Ω. The
actual voltage across its terminals
9. IF VIN increases, IZ will
when the current is 25mA is
A. 8.2 V.
B. 125 mV.
C. 8.325 V.
D. 8.075 V.
A. increase.
B. decrease.
C. remain the same.
6. A 6.2 V is rated at 1 watt. The D. none of the above.
maximum safe current the zener
can carry is
A. 1.61 A
B. 161 mA 10. If VIN decreases, IR will
C. 16.1 mA
D. 1.61 mA

7. If the load current increases, I R will

__________ and IZ will __________. A. increase.
B. decrease.
C. remain the same.
D. none of the above.
11. Identify the Schottky diode. D. d
E. e

14. Which symbol is correct for a

photodiode?

A. a
B. b
C. c
D. d
E. e A. a
B. b
12. Which symbol is correct for a zener C. c
diode? D. d
E. e

15. Which symbol is correct for an LED?

A. a
B. b
C. c
D. d A. a
E. e B. b
C. c
D. d
E. e

13. Find the tunnel diode symbol. 16. An LED is forward-biased. The diode
should be on, but no light is
showing. A possible trouble might
be
A. the diode is open.
B. the series resistor is too small.
C. none. The diode should be off if
forward-biased.
A. a
D. the power supply voltage is too
B. b
high.
C. c
17. The Schottky diode is used 22. What type of diode is commonly
A. in high-power circuits. used in electronic tuners in TVs?
B. in circuits requiring negative A. varactor
resistance. B. Schottky
C. in very fast-switching circuits. C. LED
D. in power supply rectifiers. D. Gunn

18. A tunnel diode is used 23. A varactor is a pn junction diode

A. in high-power circuits. that always operate in __________-
B. in circuits requiring negative bias and is doped to __________
resistance. the inherent capacitance of the
C. in very fast-switching circuits. depletion region.
D. in power supply rectifiers. A. forward, maximize
B. reverse, maximize
19. You have an application for a diode C. reverse, minimize
to be used in a tuning circuit. A type D. forward, minimize
of diode to use diode to use might
be 24. LEDs are made out of
A. an LED. A. silicon.
B. a Schottky diode. B. germanium.
C. a Gunn diode C. gallium.
D. a varactor D. silicon and germanium, but not
gallium.
20. Zener diodes with breakdown
voltages less than 5 V operate 25. What type of a diode maintains a
predominantly in what type of constant current?
breakdown? A. LED
A. avalanche B. zener
B. zener C. current regulator
C. varactor D. pin
D. Schottky
26. What diode operates only with
21. Zener diodes with breakdown majority carriers?
voltages greater than 5 V operate A. laser
predominantly in what type of B. tunnel
breakdown? C. Schottky
A. avalanche D. step-recovery
B. zener
C. varactor 27. What kind of diode is formed by
D. Schottky joining a doped semiconductor
region with a metal?
A. laser
 B. tunnel D. avalanche breakdown
C. pin
D. Schottky 33. A no-load condition means that
A. the load has infinite resistance
28. Which diode employs graded B. the load has zero resistance
doping? C. the output terminals are open
A. zener D. answers (a) and (c)
B. LED
C. tunnel 34. A varactor diode exhibits
D. step-recovery A. a variable capacitance that
depends on reverse voltage
29. What diode is used in seven- B. a variable resistance that
segment display? depends on reverse voltage
A. zener C. a variable capacitance that
B. LED depends on forward voltage
C. laser D. a constant capacitance over a
D. Schottky range of reverse voltages

30. Back-to-back varactor diodes are 35. An LED

used for what reason? A. emits light when reversed bias
A. over- voltage protection B. senses light when reversed bias
B. a wider tuning range C. emits light when forward bias
C. to eliminate harmonic D. acts as a variable resistance
distortion
D. no reason: only zeners are used
in a back-to-back configuration

36. Compared to a visible red LED, an

infrared LED
31. The cathode of a zener diode in a A. produces light with shorter
voltage regulator is normally wavelengths
A. more positive than anode B. produces light of all
B. more negative than anode wavelengths
C. at +0.7 V C. produces only one color of light
D. grounded D. produces light with longer
wavelengths
32. If a certain zener diode has a zener
voltage of 3.6 V, it operates in 37. Compared to incandescent bulb,
A. regulated breakdown high intensity LEDs
B. zener breakdown A. are brighter
C. forward conduction B. have a much longer life
 C. use less power C. monochromatic light
D. all of the above D. both (b) and (c)

38. An OLED differs from a conventional 42. A diode that has negative resistance
LED in that it characteristic in the
A. requires no bias voltage A. Schottky diode
B. has layers of organic material in B. tunnel diode
the place of a pn junction C. laser diode
C. can be implemented by inkjet D. hot-carrier diode
printing process
D. both (b) and (c) 43. In order for a system to function
properly, the various type of circuits
39. An infrared LED is optically coupled that make up the system must be
to a photodiode. When LED is A. properly biased
turned off, the reading on an B. properly connected
ammeter in series with the reverse- C. properly interfaced
biased photodiode will D. all of the above
A. not change E. answers (a) and (b)
B. decrease
C. increase
D. fluctuate

40. The internal resistance of a 1. The dc load line on a family of collector

photodiode characteristic curves of a transistor
A. increases with light intensity shows the
when reverse-biased A. saturation region.
B. decreases with light intensity B. cutoff region.
when reverse-biased C. active region.
C. increases with light intensity D. all of the above.
when forward-biased
D. decreases with light intensity 2. A transistor data sheet usually identifies
when forward-biased βDC as
A. hre
41. A laser diode produces B. hfe
A. incoherent light C. IC
B. coherent light D. VCE
3. When a transistor is used as a switch, it
is stable in which two distinct regions?
A. saturation and active
B. active and cutoff
C. saturation and cutoff A. saturation.
D. none of the above B. cutoff.
C. normal.
4. For a silicon transistor, when a base- D. not enough data.
emitter junction is forward-biased, it
has a nominal voltage drop of 9. You measure VCE and find it nearly equal
A. 0.7 V to zero. You now know that the
B. 0.3 V transistor is
C. 0.2 V
D. VCC

5. The value of βDC

A. is fixed for any particular transistor
B. varies with temperature
C. varies with IC A. operating in cutoff.
D. varies with temperature B. operating normally.
C. operating in saturation.
6. The term BJT is short for D. operating below cutoff.
A. base junction transistor
B. binary junction transistor 10. What is the order of doping, from
C. both junction transistor heavily to lightly doped, for each
D. bipolar junction transistor region?
7. For normal operation of a pnp BJT, the A. base, collector, emitter
base must be __________ with respect B. emitter, collector, base
to the emitter and __________ with C. emitter, base collector
respect to the collector. D. collector, emitter, base
A. positive, negative 11. What are the two types of bipolar
B. positive, positive junction transistors?
C. negative, positive A. npn and pnp
D. negative, negative B. pnn and nnp
C. ppn and nnp
8. The measured voltage, VCE is 20 V. The D. pts and stp
transistor is in
12. Which of the following is true for npn or
pnp transistor?
A. IE = IB + IC
B. IB = IC + IE
 C. IC = IB + IE B. TO-92
D. none of the above C. TO-39
D. TO-52
13. What is the ratio of IC to IB? E. all of the above
A. βDC
B. hFE 19. The magnitude of dark current in a
C. αDC phototransistor usually falls in what
D. either βDC or hFE but not αDC range?
A. mA
14. What is the ratio of IC to IE? B. µA
A. βDC C. nA
B. βDC / (βDC + 1) D. pA
C. αDC
D. either βDC / (βDC + 1) or αDC but not 20. The three terminals of a bipolar junction
βDC transistor are called:
A. p,n,p
15. In what range of voltages is the B. n,p,n
transistor in the linear region of its C. input, output, ground
operation? D. base, emitter, collector
A. 0 < VCE
B. 0.7 < VCE < VCE (max) 21. In a pnp transistor, the p regions are:
C. VCE (max) > VCE A. base and emitter
D. none of the above B. base and collector
C. emitter and collector
16. What does DC vary with? D. base, emitter, collector
A. IC
B. °C
C. Both IC and °C
D. I’C, but not °C 22. For operation as an amplifier, the base
of an npn transistor must be:
17. What is (are) common fault(s) in a BJT- A. positive with respect to emitter
biased circuit? B. negative with respect to emitter
A. opens or shorts internal to the C. positive with respect to collector
transistor D. 0 V
B. open bias resistor(s)
C. external opens and shorts on the 23. The emitter current is always:
circuit board A. greater than the base current
D. all of the above B. less than the collector current
C. greater than the collector current
18. What is (are) general-purpose/small- D. answer (a) and (c)
signal transistors case type(s)?
A. TO-18 24. The βDC of a transistor is its:
 A. current gain B. Minimum
B. voltage gain C. Maximum
C. power gain D. equal to VCC
D. internal resistance E. answer (c) and (d)

25. If IC is 50 times larger than IB, then βDC is: 31. In saturation, VCE is;
A. 0.02 A. 0.7 V
B. 100 B. equal to VCC
C. 50 C. minimum
D. 500 D. maximum

26. The approximate voltage across the 32. To saturate a BJT:

forward biased base-emitter junction of A. IB = IC (sat)
a silicon BJT is: B. IB > IC (sat) / βDC
A. 0 V C. VCC must be at least 10 V
B. 0.7 V D. the emitter must be grounded
C. 0.3 V
D. VBB 33. Once in saturation, a further increase in
base current will:
27. The bias condition for a transistor to be A. cause the collector current to
used as a linear amplifier is called: increase
A. forward-reverse B. not affect the collector current
B. forward-forward C. cause the collector current to
C. reverse-reverse decrease
D. collector bias D. turn the transistor off
34. In a phototransistor, base current is:
28. When a lowercase r’ is used to a A. set by a bias voltage
transistor, it refers to: B. directly proportional to light
A. a low resistance intensity
B. a wire resistance C. inversely proportional to light
C. an internal ac resistance intensity
D. a source resistance D. not a factor

29. When operated in cutoff saturation, the 35. The relationship between the collector
transistor acts like a: current and a light-generated base
A. linear amplifier current is:
B. switch A. IC = βDC Iλ
C. variable capacitor B. IC = αDC Iλ
D. variable resistor C. IC = λ Iλ
D. IC = β2DC Iλ
30. In cutoff, VCE is:
A. 0 V 36. An optocoupler usually consists of:
 A. two LEDs
B. an LED and a photodiode
C. an LED and a phototransistor
D. both (b) and (c)

37. In a transistor amplifier, if the base

emitter junction is open, the collector
voltage is:
A. VCC
B. 0 V
C. Floating
D. 0.2 V

38. A DMM measuring on open transistor

junction shows:
A. 0 V
B. 0.7 V
C. OL
D. VCC

1. Voltage-divider bias has a relatively

stable Q-point, as does
A. base bias.
B. collector-feedback bias.
C. both of the above.
D. none of the above.

2. Emitter bias requires

A. only a positive supply.
B. only a negative supply.
C. no supply voltage.
D. both positive and negative supply
voltages.

3. Clipping is the result of

A. the input signal being too large.
B. the transistor being driven into
saturation.
 C. the transistor being driven into C. a short from collector to emitter.
cutoff. D. no problems.
D. all of the above.
8. The most probable cause of trouble, if
4. Changes in βDC result in changes in any, from these voltage measurements
A. IC. is
B. VCE.
C. the Q-point.
D. all of the above.

5. The input resistance at the base of a

voltage-divider biased transistor can be
neglected A. the base-emitter junction is open.
A. at all times. B. RE is open.
B. only if the base current is much C. a short from collector to emitter.
smaller than the current through RZ D. no problems.
(the lower bias resistor).
C. at no time
D. only if the base current is much
larger than the current through R Z
(the lowest bias resistor).

6. Ideally for linear operation, a transistor

should be biased so that the Q-point is 9. The most probable cause of trouble, if
A. near saturation. any, from these voltage measurements
B. near cutoff. is
C. where IC is maximum.
D. halfway between cutoff and
saturation.

7. The most probable cause of trouble, if

any, from there voltage measurements
would be
A. the base-emitter junction is open.
B. RE is open.
C. a short from collector to emitter.
D. no problems.

10. The most probable cause of trouble, if

any, from these voltage measurements
A. the base-emitter junction is open.
is
B. RE is open.
 A. base bias
B. collector-feedback bias
C. voltage-divider bias
D. emitter bias

16. Which transistor bias circuit

arrangement provides good Q-point
A. the base-emitter junction is open.
stability, but requires both positive and
B. RE is open.
negative supply voltages?
C. a short from collector to emitter.
A. base bias
D. no problems.
B. collector-feedback bias
C. voltage-divider bias
11. The most stable biasing technique used
D. emitter bias
is the
A. voltage-divider bias.
17. Which transistor bias circuit
B. base bias.
arrangement provides good stability
C. emitter bias.
using negative feedback from collector
D. collector bias.
to base?
A. base bias
12. At saturation the value of VCE is nearly
B. collector-feedback bias
__________ and IC = __________.
C. voltage-divider bias
A. zero, zero
D. emitter bias
B. VCC, IC (sat)
C. zero, I(sat)
18. In the voltage-divider biased npn
D. VCC, zero
transistor circuit, if RC opens, the
transistor is
13. What is the most common bias circuit?
A. base
B. collector
C. emitter
D. voltage-divider

14. What is the dc input resistance at the

A. saturated.
base of a BJT?
B. cutoff.

B. βDC · (RC ∥ RE)

A. βDC RC
C. nonconducting.
D. none of the above.
C. βDC · re’
D. βDC RE
19. In the voltage-divider biased npn
transistor circuit, if R2 opens, the
15. Which transistor bias circuit
transistor is
arrangement has poor stability because
its Q-point varies widely with βDC?
 resulting sinusoidal collector voltage is
clipped near zero volts, the transistor is
A. Being driven into saturation
B. Being driven into cutoff
C. Operating nonlinearly
D. Answers (a) and (c)
A. saturated. E. Answers (b) and (c)
B. cutoff.
C. nonconducting. 24. The input resistance at the base of a
D. none of the above. biased transistor depends mainly on
A. βDC
20. In the voltage-divider biased npn B. RB
transistor circuit, if R1 opens, the C. RE
transistor is D. βDC and RE

25. Voltage-divider bias

A. Cannot be independent of βDC
B. Can be essentially independent of
βDC
C. Is not widely used
A. saturated. D. Requires fewer components than all
B. cutoff. the other methods
C. nonconducting.
D. none of the above.
21. The maximum value of collector current
in a biased transistor is 26. In a voltage-divider transistor circuit,
A. βDC IB RIN(BASE) can generally be neglected in
B. IC (sat) calculations when
C. greater than IE
D. IE – IB

22. Ideally, a dc load line is a straight line

drawn on the collector characteristic
curves between
A. The Q-point and cutoff A. RIN(BASE) > R2
B. the Q-point and saturation B. R2 > 10RIN(BASE)
C. VCE (cutoff) and IC (sat) C. RIN(BASE) > 10 R2
D. IB = 0 and IB = IC / βDC D. R1 << R2

23. If a sinusoidal voltage is applied to the 27. Voltage-divider bias

base of a biased npn transistor and the E. Cannot be independent of βDC
 F. Can be essentially independent of B. The transistor may be driven into
βDC cutoff
G. Is not widely used C. The transistor may be driven into
H. Requires fewer components than all saturation
the other methods D. The collector current will decrease

33. In a voltage-divider biased pnp

28. Emitter bias is transistor, there is no base current, but
A. Essentially independent of βDC the base voltage is approximately
B. very dependent on βDC correct. The most likely problem(s) is
C. provides stable bias point A. A bias resistor is open
D. answers (a) and (c) B. The collector resistor is open
C. The base-emitter junction is open
29. The disadvantage of biased is that D. The emitter resistor is open
A. It is very complex E. Answers (a) and (c)
B. It produces low gain F. Answers (c) and (d)
C. It is too beta dependent
D. It produces high leakage current

30. Collector-feedback bias is

A. Based on the principle of positive
feedback
B. Based on beta multiplication
C. Based on the principle of negative
feedback
D. Not very stable

31. In a voltage-divider biased npn

transistor, if the upper voltage-divider
resistor (the one connected to VCC)
opens,
A. The transistor goes into cutoff
B. The transistor goes into saturation
C. The transistor burns out
D. The supply voltage is too high

32. In a voltage-divider biased npn

transistor, if the lower voltage-divider
resistor (the one connected to the
ground) opens,
A. The transistor is not affected