final Flashcards
(121 cards)
1
Q
What is the bandgap of a semiconductor?
A) The energy difference between the valence band and the conduction band
B) The energy difference between the conduction band and the Fermi level
C) The energy difference between the Fermi level and the valence band
D) The energy of an electron in the conduction band
A
A) The energy difference between the valence band and the conduction band
2
Q
Which of the following materials is a commonly used intrinsic semiconductor?
A) Silicon (Si)
B) Copper (Cu)
C) Aluminum (Al)
D) Gallium (Ga)
A
A) Silicon (Si)
3
Q
The majority charge carriers in an n-type semiconductor are:
A) Holes
B) Electrons
C) Ions
D) Neutrons
A
B) Electrons
4
Q
Which of the following elements is typically used to dope silicon to create an n-type semiconductor?
A) Phosphorus (P)
B) Boron (B)
C) Gallium (Ga)
D) Arsenic (As)
A
A) Phosphorus (P)
5
Q
The Fermi level in an intrinsic semiconductor is located:
A) Above the conduction band
B) Below the valence band
C) In the middle of the bandgap
D) At the edge of the conduction band
A
C) In the middle of the bandgap
6
Q
What is the effect of increasing temperature on the conductivity of an intrinsic semiconductor?
A) Conductivity decreases
B) Conductivity remains constant
C) Conductivity increases
D) Conductivity fluctuates
A
C) Conductivity increases
7
Q
Which of the following is a property of a semiconductor in its intrinsic form?
A) It has a very high electrical conductivity
B) It has a very low electrical conductivity
C) It behaves as a good insulator
D) It has an infinite number of free electrons
A
B) It has a very low electrical conductivity
8
Q
In an n-type semiconductor, what is the role of the donor impurity?
A) To donate holes to the conduction band
B) To donate electrons to the conduction band
C) To accept electrons from the conduction band
D) To increase the bandgap
A
B) To donate electrons to the conduction band
9
Q
What is the term for a material that has both p-type and n-type regions in close proximity, forming a junction?
A) P-N junction
B) Metal-semiconductor junction
C) Bipolar junction
D) Diode junction
A
A) P-N junction
10
Q
Which of the following is true about a p-type semiconductor?
A) The majority charge carriers are electrons
B) The majority charge carriers are holes
C) It is created by doping with an element such as phosphorus
D) It is a poor conductor of electricity
A
B) The majority charge carriers are holes
11
Q
The process of adding impurities to a semiconductor to modify its electrical properties is called:
A) Diffusion
B) Doping
C) Ionization
D) Deposition
A
B) Doping
12
Q
At absolute zero (0 K), an intrinsic semiconductor behaves as:
A) A perfect conductor
B) A perfect insulator
C) A good conductor
D) A perfect dielectric
A
B) A perfect insulator
13
Q
Which of the following is the main reason that a semiconductor behaves differently from an insulator?
A) The conduction band is empty in a semiconductor at 0 K
B) The conduction band overlaps with the valence band in a semiconductor
C) The energy gap between the valence band and conduction band is small in a semiconductor
D) The Fermi level is at the middle of the conduction band in a semiconductor
A
C) The energy gap between the valence band and conduction band is small in a semiconductor
14
Q
What happens when a forward bias is applied to a p-n junction?
A) The depletion region widens
B) The current increases as charge carriers move across the junction
C) The current becomes zero
D) The junction behaves like an insulator
A
B) The current increases as charge carriers move across the junction
15
Q
In a diode, the forward voltage drop is typically around:
A) 0.3 V
B) 0.7 V
C) 1.2 V
D) 1.5 V
A
B) 0.7 V
16
Q
Which of the following statements is true about an intrinsic semiconductor?
A) The number of holes is greater than the number of electrons
B) The number of free electrons equals the number of holes
C) The number of free electrons is less than the number of holes
D) It has zero electrical conductivity at room temperature
A
B) The number of free electrons equals the number of holes
17
Q
Which of the following is NOT a semiconductor material?
A) Silicon (Si)
B) Gallium arsenide (GaAs)
C) Germanium (Ge)
D) Copper (Cu)
A
D) Copper (Cu)
18
Q
Which of the following is a key difference between intrinsic and extrinsic semiconductors?
A) Intrinsic semiconductors have no charge carriers, while extrinsic semiconductors have free electrons or holes due to doping
B) Intrinsic semiconductors are non-conductive, while extrinsic semiconductors conduct electricity
C) Extrinsic semiconductors have an equal number of electrons and holes, while intrinsic semiconductors do not
D) Intrinsic semiconductors are created by doping, while extrinsic semiconductors are pure materials
A
D) Intrinsic semiconductors are pure materials, while extrinsic semiconductors are created by doping
19
Q
Which of the following materials is commonly used for optoelectronic devices such as LEDs and laser diodes?
A) Silicon (Si)
B) Gallium arsenide (GaAs)
C) Germanium (Ge)
D) Copper oxide (CuO)
A
B) Gallium arsenide (GaAs)
20
Q
What is the typical energy bandgap for a silicon semiconductor?
A) 0.1 eV
B) 0.5 eV
C) 1.1 eV
D) 2.5 eV
A
C) 1.1 eV
21
Q
In a p-n junction diode, when reverse bias is applied, the current is:
A) Zero or very small
B) Equal to the forward current
C) Increases significantly
D) Fluctuates with time
A
A) Zero or very small
22
Q
In a p-type semiconductor, the majority carriers are:
A) Electrons
B) Holes
C) Ions
D) Neutrons
A
B) Holes
23
Q
Which of the following is a characteristic of an n-type semiconductor?
A) The majority charge carriers are holes
B) The conductivity increases with doping with a Group III element
C) The majority charge carriers are electrons
D) The Fermi level lies close to the valence band
A
C) The majority charge carriers are electrons
24
Q
In the context of semiconductors, the term “depletion region” refers to:
A) A region where there are no free charge carriers due to recombination
B) A region where the majority carriers are concentrated
C) A region with high density of charge carriers
D) A region that is full of mobile electrons
A
A) A region where there are no free charge carriers due to recombination
25
What happens when a semiconductor is doped with a Group V element such as phosphorus?
A) It becomes a p-type semiconductor
B) It becomes an n-type semiconductor
C) It behaves as an insulator
D) It creates a high-energy bandgap
B) It becomes an n-type semiconductor
26
Which of the following is the primary function of a diode?
A) To amplify signals
B) To allow current to flow in both directions
C) To allow current to flow in one direction only
D) To store electrical energy
C) To allow current to flow in one direction only
27
In a p-n junction diode, when the p-type is connected to the positive terminal of the battery and the n-type to the negative terminal, the diode is in:
A) Reverse bias
B) Forward bias
C) Breakdown region
D) No bias
B) Forward bias
28
What happens to the current in a diode when it is reverse biased?
A) The current increases exponentially
B) The current remains zero (except for leakage current)
C) The current is very high
D) The diode starts to conduct freely
B) The current remains zero (except for leakage current)
29
Which of the following is true for a diode in forward bias?
A) The p-type is connected to the negative terminal of the battery
B) The n-type is connected to the positive terminal of the battery
C) The current flows easily through the diode
D) The diode behaves like an open circuit
C) The current flows easily through the diode
30
What is the typical voltage drop across a silicon diode when it is forward biased and conducting?
A) 0.2 V
B) 0.7 V
C) 1.1 V
D) 2.0 V
B) 0.7 V
31
In a p-n junction diode, what causes the depletion region to form?
A) High temperature
B) Movement of charge carriers (electrons and holes) across the junction
C) External bias
D) None of the above
B) Movement of charge carriers (electrons and holes) across the junction
32
Which of the following is true for a Zener diode in reverse bias?
A) It conducts current only when the reverse voltage exceeds the Zener breakdown voltage
B) It behaves like a regular diode in reverse bias
C) It always blocks the current in reverse bias
D) It always conducts current in both directions
A) It conducts current only when the reverse voltage exceeds the Zener breakdown voltage
33
A diode that allows current to flow in both directions, but in a controlled manner, is known as:
A) A Schottky diode
B) A Zener diode
C) A Tunnel diode
D) A Light Emitting Diode (LED)
B) A Zener diode
34
What happens when a diode is in its breakdown region?
A) The diode blocks all current
B) The diode allows very little current to pass
C) The diode allows a large current to pass in reverse bias
D) The diode starts emitting light
C) The diode allows a large current to pass in reverse bias
35
The I-V characteristic curve of a diode shows that in reverse bias, the current:
A) Increases exponentially with reverse voltage
B) Remains zero until breakdown voltage is reached
C) Decreases exponentially with reverse voltage
D) Is unaffected by the applied reverse voltage
B) Remains zero until breakdown voltage is reached
36
Which of the following diodes is specifically designed for light emission?
A) Zener diode
B) Schottky diode
C) Light Emitting Diode (LED)
D) Tunnel diode
C) Light Emitting Diode (LED)
37
What is the main difference between a Zener diode and a regular diode?
A) A Zener diode only works in forward bias
B) A regular diode works in reverse bias, while a Zener diode does not
C) A Zener diode is designed to operate in reverse breakdown for voltage regulation
D) A Zener diode has a higher forward voltage drop
C) A Zener diode is designed to operate in reverse breakdown for voltage regulation
38
What is the typical use of a Schottky diode?
A) To regulate voltage in power supplies
B) For fast switching applications
C) As a light source in displays
D) To amplify signals in audio circuits
B) For fast switching applications
39
Which of the following is true for a diode in the "cut-off" region?
A) The diode conducts current freely
B) The diode is reverse biased and does not conduct
C) The diode is forward biased and conducting
D) The diode behaves like an ideal switch
B) The diode is reverse biased and does not conduct
40
In a P-N junction diode, which region contains the majority charge carriers (electrons in n-type and holes in p-type)?
A) Depletion region
B) Conduction band
C) Valence band
D) Both the n-type and p-type regions
D) Both the n-type and p-type regions
41
Which type of diode is used in reverse bias to protect circuits from high voltage spikes?
A) Zener diode
B) Schottky diode
C) LED
D) Light Detector Diode
A) Zener diode
42
In a p-n junction diode, which of the following occurs when it is forward biased?
A) Electrons from the n-region flow toward the p-region
B) Electrons from the p-region flow toward the n-region
C) The depletion region expands
D) The majority carriers in the n-region are recombined in the p-region
A) Electrons from the n-region flow toward the p-region
43
What is the purpose of a rectifier diode in a power supply circuit?
A) To regulate voltage
B) To prevent reverse current flow
C) To convert AC voltage to DC voltage
D) To amplify the signal
C) To convert AC voltage to DC voltage
44
What is the main characteristic of a Tunnel diode?
A) It has a high forward voltage drop
B) It can conduct current in both directions
C) It exhibits quantum tunneling and has a very small breakdown region
D) It is used for voltage regulation
C) It exhibits quantum tunneling and has a very small breakdown region
45
Which diode is most commonly used in voltage regulation?
A) Zener diode
B) Light Emitting Diode (LED)
C) Schottky diode
D) Rectifier diode
A) Zener diode
46
In a diode, the term "reverse recovery time" refers to:
A) The time taken for the diode to transition from forward bias to reverse bias
B) The time it takes for the diode to recover from reverse breakdown
C) The time the diode takes to switch from conducting to non-conducting state in reverse bias
D) The recovery time after breakdown
C) The time the diode takes to switch from conducting to non-conducting state in reverse bias
47
Which of the following is true for an ideal diode?
A) It conducts current in both directions
B) It has no forward voltage drop
C) It has an infinite reverse current
D) It behaves as an open circuit when forward biased
B) It has no forward voltage drop
48
Which of the following diodes is used for switching applications due to its very fast switching time?
A) Zener diode
B) Schottky diode
C) Light Emitting Diode (LED)
D) Tunnel diode
B) Schottky diode
49
In the I-V characteristic curve of a diode, what is the region where the current increases rapidly with a small increase in voltage after the threshold?
A) Reverse bias region
B) Forward bias region
C) Breakdown region
D) Cut-off region
B) Forward bias region
50
What is the effect of increasing temperature on the reverse current in a diode?
A) The reverse current decreases
B) The reverse current remains constant
C) The reverse current increases exponentially
D) The reverse current fluctuates
C) The reverse current increases exponentially
51
What is the primary function of a Bipolar Junction Transistor (BJT)?
A) To amplify signals
B) To store charge
C) To switch digital signals
D) To control voltage
A) To amplify signals
52
In a BJT, the base current (Ib) is:
A) Always equal to the collector current (Ic)
B) Proportional to the emitter current (Ie)
C) Larger than the emitter current
D) Unrelated to the collector current
B) Proportional to the emitter current (Ie)
53
Which of the following is the correct relationship between the collector current (Ic), base current (Ib), and emitter current (Ie) in a BJT?
A) Ie = Ic + Ib
B) Ie = Ic - Ib
C) Ic = Ie + Ib
D) Ic = Ie - Ib
A) Ie = Ic + Ib
54
In an NPN transistor, the collector current (Ic) is primarily due to the movement of:
A) Holes
B) Electrons
C) Protons
D) Ions
B) Electrons
55
Which of the following statements is true for a BJT in the active region?
A) The base-emitter junction is forward-biased, and the base-collector junction is reverse-biased
B) Both the base-emitter and base-collector junctions are forward-biased
C) Both the base-emitter and base-collector junctions are reverse-biased
D) The base-emitter junction is reverse-biased, and the base-collector junction is forward-biased
A) The base-emitter junction is forward-biased, and the base-collector junction is reverse-biased
56
In a PNP transistor, the majority charge carriers in the emitter are:
A) Electrons
B) Holes
C) Ions
D) Neutrons
B) Holes
57
What is the typical current gain (β) for a BJT?
A) 1
B) 100
C) 10,000
D) Varies widely but typically between 20 and 1000
D) Varies widely but typically between 20 and 1000
58
In a BJT, the relationship between the collector current (Ic) and the base current (Ib) can be expressed as:
A) Ic = β * Ib
B) Ic = α * Ib
C) Ic = Ib / β
D) Ic = Ib / α
A) Ic = β * Ib
59
The region of a BJT where both the base-emitter and base-collector junctions are reverse-biased is called:
A) Active region
B) Cutoff region
C) Saturation region
D) Breakdown region
B) Cutoff region
60
What is the typical voltage drop across a forward-biased base-emitter junction of a silicon BJT?
A) 0.1 V
B) 0.7 V
C) 1.1 V
D) 1.5 V
B) 0.7 V
61
Which of the following is true for a BJT in saturation mode?
A) The base-emitter junction is forward-biased, and the base-collector junction is forward-biased
B) The collector current is zero
C) The transistor operates as a switch in the "off" state
D) The base-emitter junction is reverse-biased
A) The base-emitter junction is forward-biased, and the base-collector junction is forward-biased
62
In a common-emitter configuration, the input signal is applied to the:
A) Emitter
B) Collector
C) Base
D) Both base and emitter
C) Base
63
In a common-emitter configuration, the output signal is taken from the:
A) Emitter
B) Base
C) Collector
D) Both base and emitter
C) Collector
64
For a BJT, what happens to the collector current (Ic) if the base current (Ib) is increased?
A) Ic increases proportionally
B) Ic decreases
C) Ic becomes constant
D) Ic becomes zero
A) Ic increases proportionally
65
Which of the following factors influences the current gain (β) of a BJT?
A) The size of the base
B) The temperature
C) The emitter doping level
D) All of the above
D) All of the above
66
Which configuration of a BJT is most commonly used for amplification?
A) Common-base configuration
B) Common-emitter configuration
C) Common-collector configuration
D) Common-gate configuration
B) Common-emitter configuration
67
The small-signal model of a BJT in the active region is characterized by:
A) A large resistance between the base and emitter
B) A resistance between the collector and emitter
C) A dynamic resistance between the base and emitter
D) A current source between the base and collector
C) A dynamic resistance between the base and emitter
68
In the common-emitter configuration, the output voltage is inverted with respect to the input voltage. This inversion occurs because of:
A) The negative feedback in the transistor
B) The forward-biasing of the base-emitter junction
C) The phase shift introduced by the transistor's active region
D) The saturation region effect
C) The phase shift introduced by the transistor's active region
69
Which of the following is a characteristic of a BJT in the cutoff region?
A) The transistor acts as a closed switch
B) The base-emitter junction is forward-biased
C) The collector current is almost zero
D) The transistor operates in amplification mode
C) The collector current is almost zero
70
The maximum collector current (Ic) that a BJT can handle is determined by:
A) The base-emitter voltage
B) The thermal limitations of the device
C) The collector-base voltage
D) The supply voltage
B) The thermal limitations of the device
71
In a BJT, what is the main role of the base region?
A) To provide a low-resistance path for current flow
B) To control the flow of charge carriers between the collector and emitter
C) To store charge
D) To act as a power dissipation element
B) To control the flow of charge carriers between the collector and emitter
72
Which of the following is true for a transistor in the saturation region?
A) The transistor is completely "on," with both junctions forward-biased
B) The transistor is completely "off," with both junctions reverse-biased
C) The base-emitter junction is reverse-biased, and the base-collector junction is forward-biased
D) The base-emitter junction is forward-biased, and the base-collector junction is reverse-biased
A) The transistor is completely "on," with both junctions forward-biased
73
The term "β" for a BJT refers to the:
A) Base current
B) Current gain
C) Transistor's breakdown voltage
D) Emitter current
B) Current gain
74
What is the effect of increasing the base-emitter voltage (Vbe) in a BJT?
A) The collector current decreases
B) The collector current remains constant
C) The collector current increases exponentially
D) The emitter current decreases
C) The collector current increases exponentially
75
What is the approximate value of β (current gain) for an average BJT?
A) 10
B) 50
C) 100
D) 1000
C) 100
76
1. In a transistor biasing circuit, the purpose of biasing is to:
a) Ensure the transistor operates in the active region
b) Keep the transistor in saturation mode
c) Ensure the transistor is turned off
d) Control the gain of the transistor
a) Ensure the transistor operates in the active region
77
2. Which of the following biasing techniques is most commonly used for small signal amplifiers due to its stability?
a) Fixed bias
b) Emitter bias
c) Voltage divider bias
d) Base bias
c) Voltage divider bias
78
3. What is the primary drawback of the fixed bias method for transistor biasing?
a) Poor stability of operating point
b) High cost
c) Complex circuit design
d) Requires multiple power supplies
a) Poor stability of operating point
79
4. In the voltage divider biasing method, what determines the stability of the operating point?
a) The collector resistor
b) The emitter resistor
c) The resistors in the voltage divider network
d) The transistor's β (beta) value
c) The resistors in the voltage divider network
80
5. In the emitter bias circuit, the emitter resistor improves the circuit’s:
a) Voltage gain
b) Stability against temperature variations
c) Input impedance
d) Collector current
b) Stability against temperature variations
81
6. For a transistor operating in the active region, which of the following conditions is true?
a) VBE > 0.7V for a silicon transistor
b) VCE > VBE
c) VBE = VBC
d) VCE = 0V
a) VBE > 0.7V for a silicon transistor
82
7. In the voltage divider bias circuit, the stability factor (S) is defined as:
a) The ratio of the change in base voltage to the change in emitter current
b) The ratio of the change in collector current to the change in base current
c) The ratio of the change in collector current to the change in base voltage
d) The ratio of the change in quiescent current to the change in ambient temperature
a) The ratio of the change in base voltage to the change in emitter current
83
8. In a transistor biasing circuit, the quiescent point (Q-point) is defined by which of the following?
a) The collector-emitter voltage (VCE) and collector current (IC)
b) The base-emitter voltage (VBE) and base current (IB)
c) The collector-emitter voltage (VCE) and base current (IB)
d) The base-emitter voltage (VBE) and emitter current (IE)
a) The collector-emitter voltage (VCE) and collector current (IC)
84
9. Which transistor configuration is most commonly used for high-gain voltage amplification, requiring a high input impedance and low output impedance?
a) Common emitter (CE)
b) Common base (CB)
c) Common collector (CC)
d) Common gate (CG)
a) Common emitter (CE)
85
10. In the collector feedback biasing circuit, the feedback resistor is connected between the:
a) Collector and base
b) Emitter and collector
c) Base and emitter
d) Base and ground
a) Collector and base
86
11. In the voltage divider biasing method, the emitter resistor (RE) is primarily used to:
a) Stabilize the operating point against temperature variations
b) Control the base current
c) Set the collector current
d) Provide negative feedback for gain control
a) Stabilize the operating point against temperature variations
87
12. In a common emitter transistor amplifier, the voltage gain is mainly determined by:
a) The transistor’s base-emitter resistance
b) The load resistor and the transistor’s current gain
c) The emitter resistor
d) The collector resistor and the emitter current
d) The collector resistor and the emitter current
88
13. Which of the following is the most important factor affecting the stability of the operating point in a transistor amplifier?
a) The power supply voltage
b) The temperature of the transistor
c) The transistor's gain (β)
d) The emitter resistor (RE)
d) The emitter resistor (RE)
89
14. In a voltage divider bias circuit, what is the typical function of the resistors R1 and R2?
a) Provide a stable supply voltage for the collector
b) Provide a stable base bias voltage to the transistor
c) Control the collector current
d) Increase the transistor's current gain
b) Provide a stable base bias voltage to the transistor
90
15. The fixed bias circuit is most sensitive to changes in which of the following?
a) Base-emitter voltage (VBE)
b) Collector resistor (RC)
c) Emitter resistor (RE)
d) Power supply voltage
a) Base-emitter voltage (VBE)
91
16. In a transistor amplifier circuit, which of the following is used to provide stabilization for the Q-point?
a) A capacitor in the feedback loop
b) A resistor in the emitter leg
c) A resistor in the collector leg
d) A capacitor bypassing the emitter resistor
b) A resistor in the emitter leg
92
17. For voltage-divider biasing, the voltage divider resistors R1 and R2 should be chosen such that:
a) R1 is much larger than R2
b) R11 and R2 are equal
c) The ratio R1/R2R1 is close to the required base bias voltage
d) The total power dissipation is minimized
c) The ratio R1/R2R1 is close to the required base bias voltage
93
18. In a common emitter amplifier, what happens to the collector current if the emitter resistor (RE) is bypassed by a capacitor?
a) The collector current decreases
b) The collector current increases
c) The collector current remains unchanged
d) The amplifier's gain increases
b) The collector current increases
94
19. In the voltage divider bias configuration, if the temperature increases, what happens to the collector current (IC)?
a) The collector current decreases
b) The collector current remains constant
c) The collector current increases
d) The collector current fluctuates unpredictably
a) The collector current decreases
95
20. Which of the following methods is used to improve the thermal stability of a transistor amplifier?
a) Adding a bypass capacitor across the emitter resistor
b) Using negative feedback
c) Increasing the collector resistor
d) Reducing the base resistor value
b) Using negative feedback
96
21. In a common emitter amplifier, the gain is typically defined as:
a) The ratio of output voltage to input voltage
b) The ratio of collector current to base current
c) The ratio of emitter voltage to base voltage
d) The ratio of input power to output power
a) The ratio of output voltage to input voltage
97
22. In the voltage divider biasing circuit, the current through the voltage divider resistors R1 and R2 should ideally be:
a) Very small compared to the base current of the transistor
b) Equal to the base current
c) Very large to provide enough current for the transistor
d) Much larger than the emitter current
a) Very small compared to the base current of the transistor
98
23. The emitter follower (common collector) amplifier configuration is known for:
a) High voltage gain and low current gain
b) Low voltage gain and high current gain
c) High voltage and high current gain
d) Low voltage gain and low current gain
b) Low voltage gain and high current gain
99
24. In a transistor's common base configuration, the input current is supplied to the:
a) Emitter
b) Collector
c) Base
d) Base-collector junction
a) Emitter
100
25. What is the primary disadvantage of the fixed biasing method for transistor biasing?
a) Difficulty in setting the operating point
b) Poor temperature stability
c) High cost
d) Requires complex components
b) Poor temperature stability
101
27. In a common emitter amplifier, increasing the emitter resistor (RE) will result in:
a) Increased voltage gain
b) Decreased voltage gain
c) Increased current gain
d) No effect on the voltage gain
b) Decreased voltage gain
102
1. Which of the following is the primary characteristic of a Common Emitter (CE) amplifier?
a) High input impedance and high output impedance
b) Low input impedance and high output impedance
c) High input impedance and low output impedance
d) Low input impedance and low output impedance
b) Low input impedance and high output impedance
103
2. In a Common Emitter (CE) amplifier, the voltage gain is mainly determined by:
a) The collector resistor (RC)
b) The emitter resistor (RE)
c) The base resistor (RB)
d) The coupling capacitor
a) The collector resistor (RC)
104
3. In a common emitter amplifier with negative feedback, the feedback resistor is usually placed:
a) Between the emitter and ground
b) Between the base and ground
c) Between the collector and the base
d) Between the emitter and base
c) Between the collector and the base
105
4. In a common base amplifier, the input signal is applied to the:
a) Base of the transistor
b) Emitter of the transistor
c) Collector of the transistor
d) Both the emitter and base
b) Emitter of the transistor
106
5. The gain of a Common Collector (CC) amplifier is:
a) High voltage gain and low current gain
b) Low voltage gain and high current gain
c) High voltage gain and high current gain
d) Low voltage gain and low current gain
b) Low voltage gain and high current gain
107
6. In a common emitter amplifier circuit, the coupling capacitor is used to:
a) Block the DC component of the input signal
b) Provide feedback to the base
c) Stabilize the operating point of the transistor
d) Limit the maximum output voltage
a) Block the DC component of the input signal
108
7. What is the primary function of the emitter resistor (RE) in a common emitter amplifier?
a) To increase the voltage gain
b) To stabilize the biasing point and reduce distortion
c) To set the operating point of the collector
d) To reduce the current gain of the transistor
b) To stabilize the biasing point and reduce distortion
109
8. In a common emitter amplifier, if the emitter resistor (RE) is bypassed by a capacitor, what effect does this have on the amplifier?
a) It increases the voltage gain at high frequencies
b) It decreases the voltage gain at high frequencies
c) It reduces the distortion in the output signal
d) It increases the input impedance
a) It increases the voltage gain at high frequencies
110
9. Which of the following configurations of BJT amplifier is typically used as a voltage buffer with unity gain?
a) Common base
b) Common emitter
c) Common collector
d) Common gate
c) Common collector
111
10. For a common emitter amplifier, increasing the collector resistor (RC) results in:
a) Increased voltage gain
b) Decreased voltage gain
c) Decreased output voltage
d) Increased current gain
a) Increased voltage gain
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11. In a common emitter amplifier, the output voltage swing is most limited by:
a) The emitter resistor (RE)
b) The collector resistor (RC)
c) The DC biasing conditions
d) The transistor’s saturation voltage (VCE(sat))
d) The transistor’s saturation voltage (VCE(sat))
113
12. Which of the following factors primarily determines the bandwidth of a common emitter amplifier?
a) The emitter resistor (RE)
b) The transistor’s gain (β)
c) The coupling and bypass capacitors
d) The input and output resistances of the circuit
c) The coupling and bypass capacitors
114
13. The input impedance of a common emitter amplifier is mainly determined by:
a) The emitter resistor (RE)
b) The collector resistor (RC)
c) The base resistor (RB)
d) The load resistor
a) The emitter resistor (RE)
115
14. In a common base amplifier, the input signal is applied to the:
a) Base of the transistor
b) Emitter of the transistor
c) Collector of the transistor
d) Base-collector junction
b) Emitter of the transistor
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15. The primary disadvantage of using a common base amplifier is:
a) It has very high input impedance
b) It has very low voltage gain
c) It has low input impedance
d) It is not suitable for high-frequency applications
c) It has low input impedance
117
16. In a common emitter amplifier, the presence of a bypass capacitor across the emitter resistor will:
a) Decrease the voltage gain at all frequencies
b) Increase the current gain but not affect the voltage gain
c) Increase the voltage gain at high frequencies
d) Have no effect on the voltage gain
c) Increase the voltage gain at high frequencies
118
17. The purpose of negative feedback in a common emitter amplifier is to:
a) Increase the gain
b) Reduce distortion and improve stability
c) Increase input impedance
d) Decrease output impedance
b) Reduce distortion and improve stability
119
18. In a common emitter amplifier, what happens to the output signal if the base of the transistor is bypassed?
a) The output signal is amplified in-phase
b) The output signal is inverted and amplified
c) The output signal is unaffected
d) The output signal is reduced in magnitude
b) The output signal is inverted and amplified
120
19. In a common collector amplifier, the output voltage is taken from the:
a) Collector
b) Emitter
c) Base
d) Base-emitter junction
b) Emitter
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20. In a common emitter amplifier, which of the following is true about the phase relationship between the input and output signals?
a) The input and output signals are in-phase
b) The input and output signals are 180 degrees out of phase
c) The output signal leads the input signal
d) There is no phase difference between input and output
b) The input and output signals are 180 degrees out of phase
