Test 3 Flashcards

(280 cards)

1
Q

The name of pure semiconductor material that has an equal number of electrons and holes

A. n-type
B. pure type
C. intrinsic
D. p-type

A

C. intrinsic

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2
Q

Elements that has four valence electrons are classified as

A. conductor
B. insulator
C. elemental semiconductor
D. compound semiconductor

A

C. elemental semiconductor

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3
Q

An example of an elemental semiconductor.

A. Germanium (Ge)
B. Gallium Arsenide (GaAs)
C. Gallium Phosphide (GaP)
D. Aluminum Arsenide (AlAs)

A

A. Germanium (Ge)

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4
Q

Which of the following is an example of a compound semiconductor?

A. Gallium Arsenide (GaAs)
B. Gallium Phosphide (GaP)
C. Aluminum Arsenide (AlAs)
D. All of the above

A

D. All of the above

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5
Q

Germanium has an atomic number of 32 and an atomic weight of approximately 72 amu. How many electrons, protons and neutrons are there?

A. 32, 32, 40
B. 32, 32, 104
C. 40, 32, 32
D. 40, 32, 104

A

A. 32, 32, 40

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6
Q

The chemical bond that is present in a crystal lattice of silicon atoms.

A. covalent bond
B. electrovalent bond
C. ionic bond
D. metallic bond

A

A. covalent bond

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7
Q

The atomic weight of a silicon atom is approximately 28 amu. How many electrons, protons and neutrons does the atom consist?

A. 14, 42, 14
B. 14, 14, 42
C. 42, 14, 14
D. 14, 14, 14

A

D. 14, 14, 14

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8
Q

What is the total charge at the nucleus of silicon atom?

A. -12e C
B. 12e C
C. -14e C
D. 14e C

A

D. 14e C

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9
Q

In materials, what do you call the area that separates the valence band and the conduction band?

A. energy gap
B. forbidden band
C. insulation band
D. A and B are correct

A

B. forbidden band

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10
Q

At absolute zero temperature, semiconductor acts as

A. an insulator
B. a conductor
C. a semi-insulator
D. usual

A

A. an insulator

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11
Q

The electron flow in a semiconductor material is

A. opposite in direction of hole flow
B. the same direction with hole flow
C. the drift current
D. known as the conventional current

A

A. opposite in direction of hole flow

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12
Q

Typical range of the resistivity of a semiconductor

A. 10-15 – 10-18 Ω-cm
B. 10-5 – 10-8 Ω-cm
C. 10 – 104 Ω-cm
D. 108 – 1015 Ω-cm

A

C. 10 – 104 Ω-cm

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13
Q

Chemical bond that is significant in metals

A. ionic bonding
B. electrovalent bonding
C. covalent bonding
D. metallic bonding

A

D. metallic bonding

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14
Q

A semiconductor that is free from impurities

A. intrinsic semiconductor
B. extrinsic semiconductor
C. compensated semiconductor
D. elemental semiconductor

A

A. intrinsic semiconductor

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15
Q

The process of adding impurities in a semiconductor material.

A. growing
B. diffusion
C. doping
D. depleting

A

C. doping

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16
Q

Impurities with five valence electrons.

A. acceptor
B. donor
C. trivalent
D. pentavalent

A

D. pentavalent

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17
Q

Example of acceptor impurities.

A. pentavalent impurities
B. trivalent impurities
C. tetravalent impurities
D. hexavalent impurities

A

B. trivalent impurities

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18
Q

If the substance used in doping has less than four valence electrons, it is known as

A. acceptor
B. donor
C. trivalent
D. pentavalent

A

A. acceptor

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19
Q

Commonly used as donor impurities.

A. Antimony (Sb)
B. Arsenic (As)
C. Phosphorus (P)
D. all of the above

A

D. all of the above

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20
Q

Example of trivalent impurities.

A. Boron (B)
B. Gallium (Ga)
C. Indium (In)
D. all of the above

A

D. all of the above

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21
Q

Donor-doped semiconductor becomes a

A. N-type semiconductor
B. good conductor
C. p-n semiconductor
D. P-type semiconductor

A

A. N-type semiconductor

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22
Q

What do you call a semiconductor that is doped with both donor and acceptor impurities?

A. double doped semiconductor
B. compensated semiconductor
C. compound semiconductor
D. diffused semiconductor

A

B. compensated semiconductor

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23
Q

The resistance of a semiconductor is known as

A. bulk resistance
B. intrinsic resistance
C. extrinsic resistance
D. dynamic resistance

A

A. bulk resistance

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24
Q

The most extensively used semiconductor.

A. silicon
B. germanium
C. gallium phosphide
D. gallium arsenide

A

A. silicon

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25
Semiconductor whose electron and hole concentrations are equal. A. extrinsic semiconductor B. intrinsic semiconductor C. compensated semiconductor D. doped semiconductor
B. intrinsic semiconductor
26
Silicon is widely used over germanium due to its several advantages, what do you think is its most significant advantage? A. abundant B. cheap C. temperature stable D. low leakage current
D. low leakage current
27
Current flow in a semiconductor that is due to the applied electric field. A. diffusion current B. conventional current C. drift velocity D. drift current
D. drift current
28
The movement of charge carriers in a semiconductor even without the application of electric potential. A. diffusion current B. conventional current C. drift current D. saturation current
A. diffusion current
29
Typically, how much energy is required for a valence electron to move to the conduction band for a doped semiconductor? A. 0 eV B. 0.05 eV C. 1.0 eV D. 5.0 eV
B. 0.05 eV
30
Conduction of electrons in a doped semiconductor happens at A. conduction band B. forbidden band C. valence band D. nuclei band
A. conduction band
31
Theoretically, where does the conduction of holes occur in a doped semiconductor? A. conduction band B. forbidden band C. valence band D. empty band
C. valence band
32
In energy band diagram of a doped semiconductor, the donor level A. is near the valence band B. is near the conduction band C. is exactly in between the valence and conduction band D. depends on the amount of doping
B. is near the conduction band
33
The acceptor level in a doped semiconductor A. is near the valence band level B. is near the conduction level C. is exactly in between the conduction and valence band D. will depend on the concentration of doping
A. is near the valence band level
34
In a semiconductor material, what will happen to the number of free electrons when the temperature rises? A. increases B. decreases exponentially C. decreases D. remains the same
A. increases
35
The electrical resistance of a semiconductor material will ________ as the temperature increases. A. increase B. increase exponentially C. decrease D. not change
C. decrease
36
The potential required to removed a valence electron A. valence potential B. threshold potential C. critical potential D. ionization potential
D. ionization potential
37
Among the given elements, which is considered as nonmetal? A. silicon (Si) B. germanium (Ge) C. tin (Sn) D. lead (Pb)
A. silicon (Si)
38
A semiconductor that is classified as a metalloid or semimetal A. silicon (Si) B. germanium (Ge) C. tin (Sn) D. carbon (C)
B. germanium (Ge)
39
Semiconductor that is very rare, it only occurs in minute quantities in many metal sulfides A. silicon (Si) B. germanium (Ge) C. tin (Sn) D. lead (Pb)
B. germanium (Ge)
40
Compound semiconductors are also known as A. compensated semiconductors B. amorphous semiconductors C. organic semiconductors D. inner-mettalic semiconductors
D. inner-mettalic semiconductors
41
What semiconductor that is mostly used in devices requiring the emission or absorption of lights? A. amorphous semiconductor B. organic semiconductor C. compound semiconductor D. elemental semiconductor
C. compound semiconductor
42
For high-speed integrated circuit, which semiconductor material given below is best to be used? A. silicon B. germanium C. carbon D. gallium arsenide
D. gallium arsenide
43
How much impurity concentration is needed for a sample of silicon to change its electrical property from a poor conductor to a good conductor? A. one part per hundred B. one part per thousand C. one part per million D. one part per billion
C. one part per million
44
The restriction of certain discrete energy levels in a semiconductor material can be predicted generally by using what model? A. Bohr model B. string model C. wave model D. particle model
A. Bohr model
45
Is defined as the energy acquired by an electron moving through a potential of one volt. A. electron Joules (eJ) B. electron-potential C. oxidation potential D. electron Volt (eV)
D. electron Volt (eV)
46
At room temperature, in a perfect silicon crystal, the equilibrium concentration of thermally generated electrons in the conduction band is about A. 1.5 x 105 per cubic cm. B. 1.5 x 1010 per cubic cm. C. 1.5 x 1015 per cubic cm. D. 1.5 x 1020 per cubic cm.
B. 1.5 x 1010 per cubic cm.
47
What is the basis in operation of semiconductor photoconductors? A. EHP generation B. EHP degeneration C. EHP optical degeneration D. EHP optical generation
D. EHP optical generation
48
The semiconductor that is used in xerography A. selenium (Se) B. gallium phosphide (GaP) C. cadmium compound D. organic semiconductor
A. selenium (Se)
49
A silicon material has an intrinsic concentration ni=1010 per cubic centimeter at room temperature. If it is doped with 1015 antimony atoms per cubic centimeter, what is now the approximate electron concentration at the conduction band? A. 105 electrons B. 1010 electrons C. 1015 electrons D. 1020 electrons
C. 1015 electrons
50
When an electron at the conduction band falls back to the valence band it will recombine with the hole. This is known as A. regeneration B. reunion C. combination D. recombination
D. recombination
51
Which semiconductor is mostly used to detect near infrared? A. silicon B. germanium C. carbon D. silicon carbide
B. germanium
52
What semiconductor that is good for high-temperature applications? A. indium antimonide (InSb) B. gallium anitmonide(GaSb) C. silicon carbide (SiC) D. diamond (C)
A. indium antimonide (InSb)
53
Among the given semiconductors below, which has the highest mobility? A. silicon B. germanium C. gallium arsenide D. indium antimonide
D. indium antimonide
54
A semiconducting glass is known as A. isomorphous semiconductor B. amorphous semiconductor C. organic semiconductor D. compound semiconductor
B. amorphous semiconductor
55
For an electroluminescent of green and red lights, which semiconductor is best? A. silicon carbide B. gallium arsenide C. indium antimonide D. gallium phosphide
D. gallium phosphide
56
Typical range of power dissipation for a semiconductor to be considered as “low power” or “small signal” A. less than 1 watt B. 5 < P < 10 watts C. 10 < P < 20 watts D. 20 watts above
A. less than 1 watt
57
In the design of high power semiconductor devices, it involves what factors? A. making the size of the semiconductor bigger B. packing the device into a bigger case C. excellent contact between the semiconductor and the case D. all of the above
D. all of the above
58
How to have a better high-frequency response in designing semiconductor devices? A. make the chip as small as possible B. the leads should be made shorter and smaller C. smaller packaging D. all of the above
D. all of the above
59
Before an electron can participate in the conduction of electricity, it must leave from the valence band and transfer to the conduction band. Transferring to the conduction band involves energy acquisition by an electron from external sources and this energy must be greater than the energy gap of the material. Which semiconductor material has the highest energy gap? A. Zinc Sulfide (ZnS) B. silicon (Si) C. germanium (Ge) D. Indium Antimonide (InSb)
A. Zinc Sulfide (ZnS)
60
Which of the following semiconductors has the smallest energy gap? A. ZnS B. Si C. Ge D. InSb
D. InSb
61
The ease with which a charge carrier (electron or hole) moves in a semiconductor material is known as mobility. It is also defined as the average drift velocity of electrons and holes per unit electrostatic field. Which of the semiconductor materials has the highest value of electron-mobility? A. InSb B. Ge C. Si D. AlP
A. InSb
62
In semiconductor materials, electrons have a higher value of mobility than holes, but which semiconductor material has the slowest electron-mobility? A. InSb B. GaP C. GaAs D. AlP
D. AlP
63
Solar cell is a semiconductor electric-junction device, which absorbs the radiant energy of sunlight and converts it directly and efficiently into electrical energy. This device, uses what type of semiconductor materials? A. single-crystal silicon B. amorphous or polycrystalline silicon C. GaAs, CdS, CdTe, CuS D. all of the above
D. all of the above
64
What is formed when n-type and p-type semiconductors are brought together? A. pn junction B. semiconductor junction C. energy band gap D. semiconductor diode
A. pn junction
65
PN junction acts as a one way valve for electrons because _________. A. the circuit in which the diode is used, only attempts to pump electrons in one diode B. electrons tend to follow the direction of the hole C. there is a little mechanical switch inside a diode D. when electrons are pump from P to N, free electrons and holes are force apart leaving no way for electrons to cross the junction
D. when electrons are pump from P to N, free electrons and holes are force apart leaving no way for electrons to cross the junction
66
The device that is formed when an n-type and p-type semiconductors are brought together A. pn junction B. semiconductor junction C. depletion region D. junction diode
D. junction diode
67
An external voltage applied to a junction reduces its barrier and aid current to flow through the junction A. reverse bias B. external bias C. junction bias D. forward bias
D. forward bias
68
A device containing an anode and a cathode or a pn junction of a semiconductor as the principal elements and provides unidirectional conduction. A. diode B. diac C. triode D. triac
A. diode
69
Unidirectional conduction in two-electrodes in any device other than a diode, such that rectification between the grid and cathode of a triode, or asymmetrical conduction between the collector and base of a transistor is called A. rectification B. diode action C. clipping D. clamping
B. diode action
70
The p-type material in a semiconductor junction diode is technically termed as A. positive terminal B. negative terminal C. cathode D. anode
D. anode
71
Cathode in a semiconductor junction diode is referred to the A. positive terminal B. junction C. p-type terminal D. n-type terminal
D. n-type terminal
72
The area in the semiconductor diode where there are no charge carriers A. depletion layer B. depletion region C. depletion mode D. depletion area
B. depletion region
73
Depletion region is an area in a semiconductor device where there are no charge carriers exist. This will be always near the junction of n-type and p-type materials. What causes this junction to be depleted by charge carriers? A. Due to the recombination of holes and electrons at the junction B. Due to the cancellation of positively charge protons and negatively charge electrons C. Due to the annihilation of charge carriers D. Due to the combination of positively charge holes and negatively charge electrons
D. Due to the combination of positively charge holes and negatively charge electrons
74
A junction diode is said to be forward-biased if A. Anode is supplied more positive than the cathode. B. Anode is supplied more negative than the cathode. C. A voltage greater than threshold is applied, with cathode less positive than anode. D. A voltage greater than threshold is applied, with cathode less negative than anode.
C. A voltage greater than threshold is applied, with cathode less positive than anode.
75
What do you call the very small amount of current that will flow in the diode when it is reverse biased? A. saturation current B. reverse saturation current C. cut-off current D. holding current
B. reverse saturation current
76
When the diode is supplied with forward direction potentials but with a magnitude less than the threshold voltage of the diode, still it will not “turn-on” and will only allow a very small amount of current to pass. This very small current is known A. as leakage current B. as forward saturation current C. as holding current D. as cut-off current
D. as cut-off current
77
The minimum voltage required before a diode can totally conduct in a forward direction. A. triggering voltage B. breakdown voltage C. saturation voltage D. threshold voltage
D. threshold voltage
78
What will happen to the threshold voltage of the diode when it operates at higher temperatures. A. increases B. increases exponentially C. decreases D. decreases exponentially
C. decreases
79
The forward current in a conducting diode will ______________ as the operating temperature increases. A. not be affected B. decrease C. decrease exponentially D. increase
D. increase
80
As the operating temperature of a reverse-biased diode is increased, its leakage or reverse saturation current will A. Increase B. increase exponentially C. decrease D. decrease exponentially
B. increase exponentially
81
The small value of direct current that flows when a semiconductor device has reverse bias A. surge current B. bias current C. reverse current D. current limit
C. reverse current
82
Normally, diodes will not conduct when reverse-biased, but if the reverse voltage is increased further, a point will be reached where the diode gives up and allowing the current to surge. This voltage is one of the limiting parameter of diodes and is known as A. breakdown voltage (VBR) B. peak inverse voltage (PIV) C. peak reverse voltage (PRV) D. all are correct
D. all are correct
83
For a silicon diode, calculate the current at room temperature if the forward voltage VF = 0.3 V and the reverse saturation current IS = 100 nA. A. 32.8 μA B. 10.8 μA C. 32.8 mA D. 10.8 mA
A. 32.8 μA
84
The breakdown voltage of a junction diode will ___________ A. Increase as operating temperature rises. B. Increase exponentially as operating temperature rises. C. Decrease as operating temperature rises. D. Not change as operating temperature rises.
C. Decrease as operating temperature rises.
85
Calculate the new threshold voltage of a germanium diode when it operates at 100 0C. A. 0.113 V B. 0.188 V C. 0.215 V D. 0.513 V
A. 0.113 V
86
A silicon diode has a reverse saturation current of 50 nA at room temperature. If the operating temperature is raised by 50°C, what is now the reverse saturation current? A. 105.56 nA B. 287.73 nA C. 827.89 nA D. 1.66 µA
D. 1.66 µA
87
In every increase of 10°C in the operating temperature of a diode will cause its reverse saturation current to A. decrease B. double C. triple D. quadruple
B. double
88
What do you call the resistance of the diode when operating at a steady state voltage? A. dc resistance B. dynamic resistance C. ac resistance D. average resistance
A. dc resistance
89
The resistance of the diode that is significant when operating with a small ac signal A. dc resistance B. static resistance C. dynamic resistance D. average resistance
C. dynamic resistance
90
When a diode is used in large ac voltages, the resistance that is to be considered is A. dc resistance B. static resistance C. dynamic resistance D. average resistance
D. average resistance
91
At forward bias condition, what will happen to the diode resistance when the applied voltage is increased? A. will also increase B. will increase exponentially C. will decrease D. will not change
C. will decrease
92
The primary use of Zener diode in electronic circuits. A. resistance regulator B. rectifier C. voltage regulator D. current regulator
C. voltage regulator
93
What phenomenon in electronics does an avalanche breakdown primarily dependent? A. Doping B. Recombination C. Ionization D. Collision
C. Ionization
94
When a diode is reverse biased the depletion region widens, since it is in between positively charge holes and negatively charge electrons, it will have an effect of a capacitor, this capacitance is called what? A. diffusion capacitance B. storage capacitance C. stray capacitance D. transition capacitance
D. transition capacitance
95
In a semiconductor diode, the total capacitance, that is the capacitance between terminals and electrodes, and the internal voltage variable capacitance of the junction is called A. diffusion capacitance B. transition capacitance C. depletion-region capacitance D. diode capacitance
D. diode capacitance
96
What capacitance is significant when the diode is forward biased? A. diffusion capacitance or storage capacitance B. transition capacitance C. depletion-region capacitance D. stray capacitance
A. diffusion capacitance or storage capacitance
97
A diode that is especially designed to operate as a voltage-variable capacitor. It utilizes the junction capacitance of a semiconductor diode. A. varactor B. varicap C. varistor D. A and B are correct
D. A and B are correct
98
The capacitance of a varactor will _______ when the forward bias voltage is increased. A. increase B. decrease C. exponentially decrease D. not change
A. increase
99
The time taken by the diode to operate in the reverse condition from forward conduction A. reverse recovery time B. forward recovery time C. reverse holding time D. reverse time constant
A. reverse recovery time
100
In operating a diode at high-speed switching circuits, one of the most important parameters to be considered is A. ac resistance B. diode capacitance C. noise figure D. reverse recovery time (trr)
D. reverse recovery time (trr)
101
The time required for forward voltage or current to reach a specified value after switching the diode from its reverse-to-forward-biased state. A. reverse recovery time B. forward recovery time (tfr) C. saturation time D. conduction time
B. forward recovery time (tfr)
102
The maximum power the diode can handle. A. maximum derating power B. maximum consumption power C. breakdown power D. maximum dissipation power
D. maximum dissipation power
103
What is the most important specification for semiconductor diode? A. Forward resistance B. Reverse resistance C. Peak inverse voltage D. Current capacity
D. Current capacity
104
What will happen to the power handling capability of the diode if it is to be operated at a higher temperature? A. decreases B. increases C. increases exponentially D. will not be affected
A. decreases
105
Diode parameter that will inform the user as to what factor does the power handling capability of the diode is reduced as the operating temperature is increased. A. power derating factor B. power dissipating factor C. power reduction constant D. all of the above
A. power derating factor
106
A certain diode has a maximum power dissipation of 500 mW at room temperature and a linear power derating factor of 5.0 mW/°C. How much power the diode can handle if operated at 50°C. A. 625 mW B. 505 mW C. 495 mW D. 375 mW
D. 375 mW
107
A semiconductor device especially fabricated to utilize the avalanche or zener breakdown region. This is normally operated in the reverse-region and its application is mostly for voltage reference or regulation. A. varactor diode B. zener diode C. shockley diode D. Schottky barrier diode
B. zener diode
108
Refers to a special type of diode which is capable of both amplification and oscillation. A. Junction diode B. Tunnel diode C. Point contact diode D. Zener diode
B. Tunnel diode
109
The effect obtain when the electric field across a semiconductor is strong enough which causes the free electrons to collide with valence electrons, thereby releasing more electrons and a cumulative multiplication of charge carriers occur. A. Gunn B. avalanche C. tunneling D. diffusion
B. avalanche
110
A negative resistance diode commonly used in microwave oscillators and detectors, it is sometimes used as amplifiers. This device is also known as Esaki diode. A. varactor diode B. Schottky diode C. IMPATT diode D. tunnel diode
D. tunnel diode
111
A rectifying metal-semiconductor junction A. Schottky barrier diode B. surface barrier diode C. hot-carrier or hot-electron diode D. all of the above are correct
D. all of the above are correct
112
Diode whose negative resistance depends on a specific form of quantum-mechanical bond structure of the material A. Gunn diode B. tunnel diode C. TRAPATT diode D. backward diode
A. Gunn diode
113
One of the electronic semiconductor devices known as diac, function as A. Four terminal multi-directional switch B. Two terminal bi-directional switch C. Two terminal unidirectional switch D. Three terminal bi-directional switch
C. Two terminal unidirectional switch
114
Another name of a three-layer diode. This is also considered as an ac diode. A. Shockley diode B. thyrector C. thyristor D. diac
D. diac
115
A diode whose negative resistance is dependent on the classical effects of phase shift introduced by the time lag between maximum field and maximum avalanche current, and by the transit time through the device. A. Read diode B. IMPATT diode C. TRAPATT diode D. all of the above
D. all of the above
116
What semiconductor diode that have a fine wire (called a cat-whisker) whose point is in permanent contact with the surface of a wafer of semiconductor material such as silicon, germanium or gallium arsenide? A. point-contact diode B. diac C. PiN diode D. thyrector
A. point-contact diode
117
When the p-n junction of a semiconductor diode is inserted with an intrinsic material, the diode becomes a A. backward diode B. Read diode C. Schokley diode D. PiN diode
D. PiN diode
118
A four layer semiconductor diode whose characteristic at the first quadrant is similar to that of a silicon-controlled rectifier (SCR). A. Shockley diode B. thyrector C. Schottky diode D. diac
A. Shockley diode
119
A diode that is especially processed so that its high-current flow takes place when the junction is reverse-biased. It is a variation of a tunnel diode. A. Esaki diode B. Read diode C. zener diode D. backward diode
D. backward diode
120
A silicon diode that exhibits a very high resistance in both directions up to certain voltage, beyond which the unit switches to a low-resistance conducting state. It can be viewed as two zener diodes connected back-to-back in series. A. bizener diode B. diac C. thyristor D. thyrector
D. thyrector
121
A type of Read diode that uses a heavily doped n-type material as its drift region A. IMPATT diode B. TRAPATT diode C. TUNNETT diode D. MITATT
A. IMPATT diode
122
A device containing more than one diode. An example is the full-wave bridge-rectifier integrated circuit. A. diode array B. diode IC C. diode pack D. combined diode
C. diode pack
123
Is the combination of the inductance of the leads and electrodes, capacitance of the junction, and the resistance of the junction of a semiconductor diode. A. diode impedance B. diode ac resistance C. diode reactance D. diode ac parameter
A. diode impedance
124
In a reverse-biased pn junction, the sudden large increase in current that occurs when a particular value of reversed voltage is reached, and which is due to ionization by the high intensity electric field in the depletion region. A. Zener effect B. Hall effect C. breakdown voltage D. ionization
A. Zener effect
125
The appearance of RF current oscillations in a dc-biased slab of n-type gallium arsenide in a 3.3 kV electric field A. Gunn effect B. Hall effect C. Zener effect D. avalanche
A. Gunn effect
126
The impedance presented by a junction operating in its zener breakdown region. A. diode impedance B. zener impedance C. breakdown impedance D. critical impedance
B. zener impedance
127
A curve showing the relationship between the voltage and the current of the diode at any given temperature A. characteristic curve B. transfer curve C. transfer characteristic curve D. all are correct
A. characteristic curve
128
The line that is plotted in the diode characteristic curve which represents the load A. linear line B. operating line C. load line D. transfer load line
C. load line
129
Diode is said to be operating at a point where the characteristic curve and the load line intersect. This point is technically termed as A. Q-point B. operating point C. quiescent point D. all are correct
D. all are correct
130
What will happen to the magnitude of the load-line slope when the load resistance is decreased? A. it will also decrease B. it will increase C. it will increase exponentially D. is not affected by the load
B. it will increase
131
Quiescent or Q-point position is dependent on A. the supply voltage B. the load resistance C. the type of diode D. all of the above
D. all of the above
132
A germanium diode is connected to a load resistance of 1.5 kΩ and is supplied with 12-V such that the diode will be forward biased. What is the voltage across the diode? A. approximately 12 V B. approximately 0.7 V C. approximately 0.3 V D. lack of data and can’t be solved
C. approximately 0.3 V
133
What is the drop across the diode when it is connected in series to a resistor of 1.8 kΩ and a supply voltage of 50 V. The supply voltage causes the diode to be reverse-biased. A. 50 V B. 0.7 V C. 0.3 V D. can not be solve, lack of data
A. 50 V
134
Two germanium diodes are connected in series and have a load resistance of 10 kΩ and a forward supply voltage of 5 V. Calculate the voltage across the load resistor. A. 4.7 V B. 4.4 V C. 0.6 V D. 0.3 V
B. 4.4 V
135
A silicon diode is in parallel with a germanium diode and is connected to a load resistor having a value of 20 kΩ and a forward supply voltage of 10 V. What is the approximate voltage across the silicon diode? A. 10 V B. 1.0 V C. 0.7 V D. 0.3 V
D. 0.3 V
136
136. What is the output voltage across a load resistor if it is paralleled with a forward biased silicon diode? The resistor network is supplied with 10 V. A. 0.7 V B. 9.3 V C. 10 V D. Can’t be solve, lack of data
A. 0.7 V
137
Diode circuit that is used to cut a portion of the input signal A. clipper B. clamper C. peak detector D. level shifter
A. clipper
138
A clipper circuit wherein the diode is connected in series with the load A. series clipper B. parallel clipper C. shunt clipper D. series feed clipper
A. series clipper
139
What do you call a clipper circuit wherein the diode is shunted with the load? A. series clipper B. parallel clipper C. cascade clipper D. cascade clipper
B. parallel clipper
140
A network with a diode and a capacitor that is used to shift the dc-level of the input signal A. clipper B. clamper C. shifter D. level inverter
B. clamper
141
Half-wave rectifier is a good example of A. a series clamper B. a parallel clamper C. a parallel clipper D. a series clipper
D. a series clipper
142
Which of the given circuit below must have a capacitor? A. rectifier B. clipper C. clamper D. all of the above
C. clamper
143
How many capacitors are used in a diode-capacitor half- wave voltage doubler? A. 1 B. 2 C. 3 D. 4
B. 2
144
An improvement of a diode-capacitor half-wave voltage doubler is the full-wave doubler, this circuit uses how many capacitors? A. 1 B. 2 C. 3 D. 4
B. 2
145
In a diode-capacitor voltage quadrupler, what is the voltage across the third stage capacitor? A. Vmax B. 2 Vmax C. 3 Vmax D. 4 Vmax
B. 2 Vmax
146
A combination of several diodes in a single housing A. diode array B. diode network C. diode IC D. diode matrix
A. diode array
147
A chopper, employing an alternately biased diodes as the switching element. A. diode chopper B. active chopper C. junction chopper D. all are correct
A. diode chopper
148
A light emitting diode (LED) is to be used in a circuit with a supply voltage of 5 V. What should be the value of the resistor needed by the LED to operate normally? A. 25 Ω B. 250 Ω C. 25 kΩ D. 250 kΩ
B. 250 Ω
149
A simple voltage-regulator whose output is the constant voltage drop developed across a zener diode conducting in the reverse breakdown region. The regulator circuit consists of a zener diode in parallel with the load and an appropriate limiting resistor. A. ordinary voltage regulator B. zener voltage regulator C. series voltage regulator D. switching voltage regulator
B. zener voltage regulator
150
Logic circuitry in which a diode is the logic element and a transistor acts as an inverting amplifier. A. RTL B. DTL C. HDTL D. ECL
B. DTL
151
What is a bridge rectifier having diodes in two arms and resistors in the other two? A. full-wave bridge B. half-wave bridge C. half-bridge D. full bridge
C. half-bridge
152
An over-voltage protection circuit employing a zener diode and an SCR whose function is to produce high overload by-pass current on a circuit. A. regulator B. current enhancer C. crowbar D. shunted zener
C. crowbar
153
The flow of electron in a NPN transistor when used in electronic circuit is from _______. A. collector to base B. collector to base C. emitter to collector D. base to emitter
C. emitter to collector
154
A three terminal, three layer semiconductor device that has the ability to multiply charge carriers. This device was first introduced at Bell Laboratories, by Brattain and Bardeen in 1947 and which opens a completely new direction of interest and development in the field of electronics. A. triode B. triac C. SCR D. transistor
D. transistor
155
An active semiconductor device, capable of amplification, oscillation, and switching action. It is an acronym for transfer resistor and had replaced the tube in most applications. A. thyristor B. thyrector C. SBS D. transistor
D. transistor
156
Transistor replaces the old vacuum tubes because it has several obvious advantages, what are they? A. smaller, lightweight and rugged construction B. no heater loss, low operating voltage and therefore efficient C. low power consumption and low power dissipation D. all of the above
D. all of the above
157
Which of the three regions/areas in a transistor that is the smallest in construction? A. emitter B. collector C. base D. all are equal
C. base
158
The region or area in a transistor that is heavily doped A. at the junction B. emitter C. collector D. base
B. emitter
159
A transistor in which the base is diffused and the emitter is alloyed. The collector is provided by the semiconductor substrate into which alloying and diffusion are affected. A. alloy-transistor B. alloy-diffused transistor C. alloy junction transistor D. diffused junction transistor
B. alloy-diffused transistor
160
A transistor whose junctions are created by alloying A. alloy transistor B. alloy-diffused transistor C. diffused transistor D. alloy junction
A. alloy transistor
161
In a semiconductor device, a p-n junction formed by alloying a suitable material such as indium with the semiconductor. A. alloy junction B. diffused junction C. depletion junction D. storage junction
A. alloy junction
162
A transistor in which one or both electrodes are created by diffusion A. diffused transistor B. alloy transistor C. planar transistor D. mesa transistor
A. diffused transistor
163
A two-junction transistor whose construction takes the form of a pnp or a npn. Such device uses both electron and hole conduction and is current-driven. A. bipolar transistor B. unipolar transistor C. bi-directional transistor D. double junction transistor
A. bipolar transistor
164
The predecessor of the junction transistor, and is characterized by a current amplification factor, alpha of greater than one. A. surface-charge transistor B. surface-barrier transistor C. schottky transistor D. point-contact transistor
D. point-contact transistor
165
For a transistor, the outer layers are A. lightly doped semiconductors B. heavily doped semiconductors C. no doping at all D. A and B above
B. heavily doped semiconductors
166
The ratio of the total width of the outer layers to that of the center layer A. 100:1 B. 150:5 C. 150:1 D. 1:150
C. 150:1
167
The ratio of the doping level of the outer layers to that of the sandwiched material A. 10:3 or more B. 10:2 or more C. 10:3 D. 10:1 or less
D. 10:1 or less
168
Limiting the number of “free” carriers will A. increase the conductivity but decreases the resistance B. decrease the conductivity but increases the resistance C. increase the conductivity as well as resistivity D. decrease the conductivity as well as resistivity
B. decrease the conductivity but increases the resistance
169
The term ________ reflects the fact that holes and electrons participate in the injection process into the oppositely polarized material. A. unipolar B. bipolar C. tetrode D. pentode
B. bipolar
170
What device, that employs only electron or hole? A. unipolar B. bipolar C. tetrode D. pentode
A. unipolar
171
At forward-biased junction of pnp transistor, majority carriers flow heavily A. from p- to the n-type material B. from n- to the p-type material C. from p- to p-type material D. A and B above
A. from p- to the n-type material
172
The minority-current component of a transistor is called A. leakage current B. emitter current C. cut-off current D. all of the above
A. leakage current
173
For general-purpose transistors, IC is measured in ____, while ICO is measured in ____. A. micro and nanoamperes B. milliamperes and microamperes C. milliamperes and nanoamperes D. b and c above
D. b and c above
174
Is temperature sensitive, and can severely affect the stability of the system, when not carefully examined during design A. IC B. ICO C. IS D. IE
B. ICO
175
For the transistor, the arrow in the graphic symbol defines the direction of _______ through the device A. leakage current flow B. emitter electron flow C. majority carrier flow D. emitter conventional current flow
D. emitter conventional current flow
176
In the dc mode, the levels of IC and IE due to the majority carriers are related by the quantity A. alpha (α) B. beta (β) C. gamma (γ) D. A and B above
A. alpha (α)
177
In the ac mode, alpha α is formally called A. common-base, short-circuit, amplification factor B. common-emitter, amplification factor C. common-collector, amplification factor D. all of the above are correct
A. common-base, short-circuit, amplification factor
178
Phrases “not pointing in” and “pointing in” simply mean A. npn and pnp B. pnp and npn C. npn only D. pnp only
A. npn and pnp
179
In the dc mode, the levels of IC and IB are related by a quantity called A. α B. β C. γ D. A and B above
B. β
180
For practical transistor devices, the level of β typically ranges A. from about 25 to over 400 B. less than 1 C. mostly in midrange of 50 to 400 D. A or C above
C. mostly in midrange of 50 to 400
181
The formal name of βac A. Common-collector reverse-current amplification factor B. Common-collector forward-current amplification factor C. Common-emitter forward-current amplification factor D. Common-emitter reverse-current amplification factor
C. Common-emitter forward-current amplification factor
182
It is a particularly important parameter that provides a direct link between current levels of the input and output circuits for a common-emitter configuration. A. α B. β C. A and B above D. none of the above
B. β
183
The _______ id defined as that area below IC= ICEO. A. active region B. cutoff region C. saturation region D. none of the above
B. cutoff region
184
It is referred to as the communication link between the manufacturer and user A. specification sheet B. characteristic manual C. characteristic curve D. all of the above
D. all of the above
185
The information that can be found in most specification sheets? A. maximum ratings B. thermal characteristics C. electrical characteristics D. all of the above
D. all of the above
186
With an ohmmeter, a large or small resistance in either junction of an npn or pnp transistor indicates A. faulty device B. well functioning device C. leaky device D. either A or C
A. faulty device
187
At base-emitter junction, using an ohmmeter, if the positive (+) lead is connected to the base and the negative (-) lead to the emitter, a low resistance reading would indicate A. npn transistor B. pnp transistor C. germanium transistor D. silicon transistor
A. npn transistor
188
At base-emitter junction, if the positive (+) lead is connected to the base and the negative (-) lead to the emitter, a high resistance reading would indicate A. npn transistor B. pnp transistor C. germanium transistor D. silicon transistor
B. pnp transistor
189
Transistors of heavy duty construction A. high-power devices B. low-power devices C. medium-power devices D. all of the above
A. high-power devices
190
On a voltage-current condition curve, the point belong to which a further increase in voltage produces no (or very little) further increase in current. A. saturation flux B. saturation value C. saturation point D. all of the above
C. saturation point
191
It is applied to any system where levels have reached their maximum values A. saturation B. active C. cutoff D. quiescent point
A. saturation
192
For an “on” transistor, the voltage VBE should be in the neighborhood of A. 0.3 V B. 0.55 V C. 0.7 V D. 1.7 V
C. 0.7 V
193
Among the three characteristics of a transistor amplifier, which region is normally employed for linear (undistorted) amplifiers? A. active region B. cutoff region C. saturation region D. capital region
A. active region
194
In the active region, the collector-base junction is ________, while the base-emitter junction is ________. A. forward and forward-biased B. forward and reverse-biased C. reverse and reverse biased D. reverse and forward-biased
D. reverse and forward-biased
195
It is necessary, in order to establish the proper region of operation for ac amplification. A. ac biasing B. dc biasing C. A and B above D. none of the above
B. dc biasing
196
At cutoff region, the collector-base and base-emitter junctions of a transistor are A. both reverse-biased B. forward and reverse-biased C. both forward-biased D. reverse and forward-biased
A. both reverse-biased
197
In saturation region, the collector-base and base-emitter junctions of a transistor are A. both reverse-biased B. forward and reverse-biased C. both forward-biased D. reverse and forward-biased
C. both forward-biased
198
If the base-emitter junction is reverse biased and the base-collector junction is forward biased, the transistor will be at what region of operation? A. active region B. cut-off region C. saturation region D. breakdown region
B. cut-off region
199
Under what region does the transistor operate if both the base-emitter and base-collector junctions are reverse-biased? A. active region B. cut-off region C. saturation region D. breakdown region
B. cut-off region
200
What region the transistor should be operating to have minimum distortion at the output signal? A. active region B. cut-off region C. saturation region D. none of the above
A. active region
201
In dc biasing, it means quiet, still, inactive A. passive B. quench C. static D. quiescent
D. quiescent
202
The transistor terminal that handles most current A. base B. collector C. emitter D. collector and emitter
C. emitter
203
Which indicates the degree of change, in operating-point due to temperature variation in the dc biasing? A. temperature coefficient B. factor of safety C. merit factor D. stability factor
D. stability factor
204
What best describes the transistor current that flows between the collector and emitter terminals when the base is open? A. leakage current B. cut-off current C. reverse saturation current D. all of the above
B. cut-off current
205
Solve for the base current if collector current is 600 mA and the current gain is 20. A. 30 mA B. 3 mA C. 12 mA D. 1.2 mA
A. 30 mA
206
When the transistor is saturated, VCE is approximately A. 0 V B. ½ VCC C. VCC D. infinite
A. 0 V
207
Collector-emitter resistance of ideal transistor at cut-off A. 0 Ω B. infinite C. a function of the load resistance D. a function of the collector current
B. infinite
208
The leakage current that flows at the collector-base junction when the emitter is open A. ICO B. ICBO C. ICEO D. ICBE
B. ICBO
209
A transistor with β = 100 is connected as common base, was found to have a leakage current ICBO = 1µA. If the transistor is configured as common emitter, what is the approximate value of its ICEO? A. 0.01 µA B. 1.0 µA C. 100 µA D. 10 mA
C. 100 µA
210
The most correct technical term of the reverse leakage current that flows between the collector and base junctions when the emitter is open circuited. A. leakage current B. saturation current C. reverse saturation current D. cut-off current
C. reverse saturation current
211
How is the collector cut-off or reverse saturation current ICBO related to the emitter cut-off current IEBO? A. ICBO β IEBO p B. ICBO IEBO/β C. ICBO IEBO(1-α) D. ICBO IEBO
D. ICBO IEBO
212
ICBO of an ideal transistor A. increases as temperature increases B. increases as temperature decreases C. is not affected by a temperature change D. is zero (0) mA
D. is zero (0) mA
213
The maximum voltage that can be applied across the collector-emitter terminal for a given transistor is specified as A. VCEO B. VECO C. V(BR)BEO D. V(BR)CEO
D. V(BR)CEO
214
If the current-gain-bandwidth product of transistor is 250 MHz and is operated at 100 MHz, what is the effective current gain of the transistor? A. 2.5 B. 25 C. 250 D. 350
A. 2.5
215
The current gain of a transistor decreases as the operating frequency increases. As the operating frequency is increased continuously, a point occurs where the current gain becomes unity. This point, is best described by what transistor parameter? A. unity gain frequency B. 0 dB frequency C. cut-off frequency D. unity gain bandwidth product or unity current gain bandwidth product
D. unity gain bandwidth product or unity current gain bandwidth product
216
When base is common to both the input and output sides of the configuration and is usually the terminal closes to, or at ground potential, it is called what? A. common-emitter terminology B. common-collector terminology C. common-base terminology D. all of the these
D. all of the these
217
Which transistor configuration has the highest input resistance? A. common base B. common emitter C. common collector D. common transistor
C. common collector
218
One of the following amplifier characteristic refers to that of a common-base (C-B) as compared to common-emitter (C-E) and common-collector (C-C) amplifiers. A. Has larger current gain B. Has lower input resistance C. Has higher input resistance D. Has larger voltage gain
B. Has lower input resistance
219
A transistor is said to be configured as common emitter if the emitter terminal is A. grounded B. connected to V+ C. floating D. not used as an input nor output
D. not used as an input nor output
220
Most frequently used transistor configuration for pnp and npn A. common-base B. common-collector C. common-emitter D. A and C above
C. common-emitter
221
Calculate the common-emitter amplification factor β of a transistor with a common-base amplification factor α=0.99. A. 10 B. 50 C. 100 D. 200
C. 100
222
Which transistor configuration hybrid parameters, that is usually specified by the manufacturers? A. for common-base B. for common-collector C. for common-emitter D. a combination of the three configurations
C. for common-emitter
223
For a common-emitter transistor configuration, the hybrid parameter hfe stands for forward transfer current ratio. This parameter is approximately equal to A. HFE B. βac C. β D. all of the above
D. all of the above
224
Hybrid parameter that is usually neglected in circuit analysis A. hi and ho B. hr and hf C. hi and hf D. hr and ho
D. hr and ho
225
The input impedance of a common-base configuration is hib, and its magnitude is approximately equal to A. hie/hfe B. hie/(1+β) C. re for dynamic model D. all of these
D. all of these
226
In most transistor input equivalent circuit it comprises of a resistor and a A. voltage source B. stiff voltage source C. current source D. stiff current source
A. voltage source
227
Which transistor configuration has the highest input resistance? A. common-base B. common-collector C. common-emitter D. emitter follower
B. common-collector
228
Common-base configuration has a high voltage gain and a current gain of A. low B. moderate C. high D. approximately equal to one (1)
D. approximately equal to one (1)
229
Common-collector has the lowest power gain and a voltage gain of approximately one. In contrast to this, what configuration has the highest power gain? A. common-base B. common-collector C. common-emitter D. emitter follower
C. common-emitter
230
Which of the following transistor characteristic curves that is most useful? A. input characteristic curve B. output characteristic curve C. transfer characteristic curve D. all of the above
B. output characteristic curve
231
The graph of the product of collector-emitter voltage VCE and collector current IC in the transistor output characteristic curve. A. maximum power curve B. minimum power curve C. saturation power curve D. breakdown curve
A. maximum power curve
232
The base of a transistor serves a purpose to what element of the FET? A. source B. ground C. substrate D. gate
D. gate
233
What is the primary difference between the BJT and the FET? A. current-controlled device and voltage-controlled device, respectively B. voltage-controlled device and current-controlled device, respectively C. impedance transformed device and conductance transformed device, respectively D. A and C above are correct
A. current-controlled device and voltage-controlled device, respectively
234
Another difference between a BJT and a FET with regards to its normal biasing. A. The input circuit is forward-biased for BJT while reverse for FET. B. The input circuit is reverse-biased for BJT while forward for FET. C. The output circuit is forward-biased for BJT while reverse for FET. D. The output circuit is reverse-biased for BJT while forward for FET.
A. The input circuit is forward-biased for BJT while reverse for FET.
235
Field-effect transistors (FETs) offer high input impedance than BJT. What makes FETs have high input impedance? A. The way FETs are constructed. B. Because of the materials used. C. Due to the level of doping D. Due to the reverse-biased input circuit of FETs
D. Due to the reverse-biased input circuit of FETs
236
The operation of BJT involves both the flow of electrons and holes and is therefore, considered as a bipolar device. Unlike BJT, FET’s operation involves only either electrons or holes and is considered as a _________ device. A. single polar B. unipolar C. unpolar D. polarized
B. unipolar
237
Considered as the basic FET or the simplest form of FET A. JFET B. MOS-FET C. IGFET D. VMOS-FET
A. JFET
238
Junction field effect transistor or JFET has three terminals, which corresponds to the E-B-C of the BJT? A. D-S-G B. D-G-S C. S-G-D D. S-D-G
C. S-G-D
239
One obvious advantage of a JFET over BJT is its A. high voltage gain B. high current gain C. high input resistance D. high output resistance
C. high input resistance
240
A BJT is a current-controlled current-source device while JFET is a _________ device. A. current-controlled voltage-source B. voltage-controlled voltage-source C. voltage-controlled current-source D. voltage-controlled transconductance-source
C. voltage-controlled current-source
241
What do you call the area in a JFET where current passes as it flows from source (S) to drain (D). A. channel B. substrate C. depletion D. drift
A. channel
242
What will happen to the channel of a JFET as current flows to it? A. widens B. narrows C. skews D. nothing
C. skews
243
For a normal operation of an n-channel JFET, how do you bias the gate-source junction? A. positive-negative respectively B. negative-positive respectively C. forward-biased D. any of the above
B. negative-positive respectively
244
The voltage across the gate-source terminal of a FET that causes drain current ID equal to zero. A. saturation voltage B. threshold voltage C. cut-off voltage D. pinch-off voltage
D. pinch-off voltage
245
The current that flows into the channel of a JFET when the gate-source voltage is zero. A. drain-source saturation current B. drain-source cut-off current C. drain-source leakage current D. drain-source pinch-off current
A. drain-source saturation current
246
The graph of the drain current ID versus drain-source voltage VDS with VGS as the parameter. A. transfer characteristic curve B. output characteristic curve C. input characteristic curve D. current-voltage characteristic curve
D. current-voltage characteristic curve
247
In FET, the conduction path of the output is controlled by the electric field as its name implies. How does an electric field in FET established? A. By the charges present at the gate due to the reverse-biased junction. B. By the application of reverse-biased between the gate and drain. C. By the charges produced due to the applied potential between drain and source VDS. D. By the charges present at each terminal due to the applied potential.
A. By the charges present at the gate due to the reverse-biased junction.
248
An early version of the field effect transistor in which limited control of current carriers near the surface of a semiconductor bar or film was obtained by an external electric field applied transversely. A. fieldistor B. JFET C. IGFET D. MOSFET
A. fieldistor
249
A FET in which the gate electrode consists of a pn junction A. JFET B. fieldistor C. MOS-FET D. IGFET
A. JFET
250
Which type of FET has the lowest input resistance? A. JFET B. MOS-FET C. IGFET D. VMOSFET
251
In order to increase further the input resistance of a FET, its gate is insulated. An example of this type is the A. fieldistor B. JFET C. MOS-FET D. A and B above
C. MOS-FET
252
What is the insulator used in most MOS-FET? A. CO2 B. SiO2 C. mica D. plastic
B. SiO2
253
An n-channel JFET has a drain-source saturation current IDSS = 10 mA and a gate-source pinch-off voltage Vp = -4 V. If the applied reverse gate-source voltage VGS = 2 V, calculate the drain current ID. A. 2.5 mA B. 5.0 mA C. 10.0 mA D. 22.5 mA
A. 2.5 mA
254
Base from Shockley’s equation of a JFET, what is the drain current when the applied voltage VGS is exactly equal to the pinch-off voltage Vp? A. IDSS B. maximum C. minimum D. zero
D. zero
255
The transconductance of a JFET is defined as A. dID/dVGS B. dVGS/dID C. dIDSS/dVGS D. dID/dVp
A. dID/dVGS
256
A field-effect transistor in which the gate electrode is not a pn junction (as in the junction field-effect transistor) but a thin metal film insulated from the semiconductor channel by a thin oxide film. A. MOSFET (enhancement type) B. MOSFET (depletion type) C. IGFET D. all of the above
D. all of the above
257
In MOSFET, it is the foundation upon which the device will be constructed and is formed from a silicon base A. substrate B. slab C. source D. base
A. substrate
258
A type of MOSFET wherein originally there is no channel between the drain and the source A. depletion type B. enhancement type C. break type D. insulated type
B. enhancement type
259
What type of MOSFET whose channel is originally thick but narrows as the proper gate bias is applied? A. enhancement B. depletion C. transverse D. all of the above
B. depletion
260
The amount of voltage needed at the gate-source terminal for an enhancement type MOSFET so that a channel can be formed for the current to flow. A. “ON” voltage B. pinch-off voltage C. threshold voltage D. trigger voltage
C. threshold voltage
261
To switch off the depletion type MOSFET, the channel should be depleted. Depletion of the channel is done by applying enough voltage across the gate-source terminal. What do you call this voltage? A. pinch-off voltage B. trigger voltage C. holding voltage D. threshold voltage
A. pinch-off voltage
262
The substrate of a MOSFET is usually connected internally to A. source B. gate C. drain D. channel
A. source
263
In an n-channel enhancement type MOSFET, the gate voltage should be ________ with respect to the source in order to produce or enhance a channel. A. the same B. positive C. negative D. either positive or negative
B. positive
264
To deplete a channel from a p-channel IGFET depletion type, the gate voltage should be ________ with respect to the source. A. the same B. positive C. negative D. either positive or negative as long as it is greater
B. positive
265
The substrate used in a p-channel IGFET enhancement type A. n -type material B. n+ -type material C. p -type material D. p+ -type material
A. n -type material
266
The base material of a MOSFET which extends as an additional terminal A. source (S) B. channel (C) C. drain (D) D. substrate (SS)
D. substrate (SS)
267
Which FET that has a substrate? A. MOSFET enhancement type B. IGFET C. MOSFET depletion type D. all of the above
D. all of the above
268
What is the difference between a JFET and a MOSFET? A. The gate of a MOSFET is insulated. B. MOSFET uses a substrate in its construction. C. MOSFET can work in both forward and reverse gate-source voltages. D. all of the above
D. all of the above
269
Calculate the transconductance of a p-channel MOSFET enhancement type if the gate-source voltage VGS = -8 V, threshold voltage VT = -4 and a constant k = 0.3 mA/V2. A. 1.2 mS B. 2.4 mS C. 3.6 mS D. 7.2 mS
B. 2.4 mS
270
One drawback of JFET devices is the strong dependence of the devices’ parameters on the channel geometry. Which parameter is an example of this? A. drain saturation current (IDSS) B. pinch-off voltage (VP) C. transconductance (gm) D. all of the above
D. all of the above
271
JFET cutoff frequency is dependent on channel length by a factor of A. 1/L B. 1/L2 C. 1/L3 D. 1/L4
B. 1/L2
272
Which FET operates as close as BJT in terms of switching? A. JFET B. MOSFET depletion type C. MOSFET enhancement type D. IGFET
C. MOSFET enhancement type
273
Generally, MOSFET has low power handling capability than BJT. To increase MOSFET power, the channel should be made A. narrow and long B. narrow and short C. wide and long D. wide and short
D. wide and short
274
Which FET has a wide and short effective channel? A. JFET B. MOSFET C. IGFET D. V-MOSFET
D. V-MOSFET
275
A type of FET wherein the channel is formed in the vertical direction rather than horizontal A. JFET B. MOSFET C. IGFET D. V-MOSFET
D. V-MOSFET
276
Advantage or advantages of V-MOS over BJT A. No stored charge and therefore faster in switching action. B. A negative temperature dependence of output current which eliminates thermal runaway. C. High input impedance and therefore high current gain. D. all of the above
D. all of the above
277
In general, which of the transistors is particularly more useful in integrated-circuit (IC) chips? A. BJTs B. FETs C. UJTs D. all of the above
B. FETs
278
A monolithic semiconductor-amplifying device in which a high-impedance GATE electrode controls the flow of current carriers through a thin bar of semiconductor called the CHANNEL. Ohmic connections made to the ends of the channel constitute SOURCE and DRAIN electrodes. A. BJT B. UJT C. FET D. UPT
C. FET
279
A junction field effect transistor has a drain saturation current of 10 mA and a pinch-off voltage of -4 V. Calculate the maximum transconductance. A. 2.5 mS B. 5.0 mS C. 25.0 mS D. 50.0 mS
B. 5.0 mS
280
In semiconductor application, which of the following statement is not true? A. An ohmmeter test across the base-collector terminal of a transistor should show low resistance in one polarity and high resistance in the opposite polarity. B. A triac is a bidirectional device. C. An ohmmeter test across a diode shows low resistance in one polarity and high resistance in the opposite polarity. D. An ohmmeter test across the base-collector of a transistor should show low resistance for both polarities.
D. An ohmmeter test across the base-collector of a transistor should show low resistance for both polarities.