MCQs in Microelectronics Part II

This is the Multiples Choice Questions Part 2 of the Series in Microelectronics as one of the Electronics Engineering topic. In Preparation for the ECE Board Exam make sure to expose yourself and familiarize in each and every questions compiled here taken from various sources including but not limited to past Board Exam Questions in Electronics Engineering field, Electronics Books, Journals and other Electronics References.

Multiple Choice Questions Topic Outline

• MCQs in Microelectronics
• MCQs in Integrated Circuits components
• MCQs in Characteristics and products (ICs)
• MCQs in Operational Amplifiers
• MCQs in Multivibrators

The  Series

Following is the list of multiple choice questions in this brand new series:

Microelectronics MCQs

PART 1: MCQs from Number 1 – 50                        Answer key: PART I

PART 2: MCQs from Number 51 – 100                   Answer key: PART II

PART 3: MCQs from Number 101 – 150                 Answer key: PART III

Continue Practice Exam Test Questions Part 2 of the Series

51. What is the typical input bias current of a 741 operational amplifier?

• A. 70 nA
• B. 80 nA
• C. 90 nA
• D. 100 nA

52. The ______ of an op amp is its voltage gain when there is no negative feedback

• A. CMRR
• B. Unity gain
• C. Close-loop
• D. Open-loop

53. The term monolithic is derived tom a combination of the Greek words monos and lithos which means

• A. Single-element
• B. Single-water
• C. Single-stone
• D. Single-chip

54. A technique used to eliminate the need for inductive elements in monolithic integrated circuits.

• A. Projection printing
• B. Photolithographic
• C. LC synthesis
• D. RC synthesis

55. Most linear ICs are low-power devices with power dissipation ratings of

• A. 5 W
• B. 1 µW
• C. Less than 1 W
• D. More than 1 W but less than 2 W

56. An integrated circuit for both astable and monostable applications

• A. 741 op-amp
• B. Discrete ICs
• C. Monolithic ICs
• D. 555 timer

57. Astable multivibrator is

• A. A square wave clock
• B. Equivalent to a flip-flop
• C. A one-shot multivibrator
• D. Monostable in nature

58. In a 5 V level detector circuit

• A. The noninverting input is connected to +5V
• B. The input signal is connected to +5V
• C. The inverting input is connected to +5V
• D. The input signal must be riding on a +5V dc level

59. To convert a summing amplifier of an averaging amplifier

• A. All inputs must be of the same value
• B. The ratio of Rf/R must equal to the reciprocal of the number of inputs
• C. All input resistors must be of different value
• D. The ratio of Rf/R must equal to the number of inputs

60. An oscillator is described by

• A. Regenerative feedback
• B. No feedback
• C. An integrator or differentiator
• D. Unity gain and zero phase shift around the feedback loop

61. To use a comparator for zero-level detection, the inverting input is connected to

• A. Ground
• B. A positive reference voltage
• C. The dc supply voltage
• D. A negative reference voltage

62. In most modern IC op-amps, the 741 requires ______ power supplies

• A. 1
• B. 2
• C. 3
• D. 4

63. In an op-amp integrator, the feedback path consist of

• A. A capacitor
• B. An inductor
• C. A resistor and a capacitor in series
• D. A resistor and a capacitor in parallel

64. Microwave ICs cover the frequency range from

• A. 0.5 to 15 GHz
• B. 15 to 30 GHz
• C. 30 to 45 GHz
• D. 45 to 100 GHz

65. Considered as the fundamental form of IC

• A. Hybrid
• B. MSI
• C. VLSI
• D. Monolithic

66. Plastic dual-in-line for insertion into sockets has a package suffix code of

• A. N
• B. P
• C. Both a and b
• D. J

67. What is the specific application of µA741C op-amp

• A. For commercial
• B. For industrial
• C. For military
• D. For experimental

68. What is the most common method used for growth of single crystals for IC fabrication?

• A. Epitaxial growth
• B. Czochralsky pulling technique
• C. Film deposition
• D. Photolithography

69. The charge-coupled device (CCD) is a unique and versatile semiconductor structure invented in 1969 by

• A. W.S Boyle and G.E Smith
• B. W.F Davis and R.C Huntington
• C. D. Cave and W. Blood Jr.
• D. H.H Strellrecht and C.S. Meyer

70. The value of the input voltage that switches the output of a comparator or Schmitt trigger

• A. Trip point
• B. Firing voltage
• C. Threshold voltage
• D. All of the choices

71. A type of ground that appears at the inverting input of an op-amp that uses negative feedback.

• A. Earth ground
• B. Equipment ground
• C. True ground
• D. Virtual ground

72. The intel i486 32-bit microprocessor incorporates _______ transistors on a single chip.

• A. 1 million
• B. 100 thousand
• C. 2 million
• D. 200 thousand

73. In IC op-amps, the input bias current is defined as the

• A. Average of the two base currents
• B. Total of the base currents
• C. Inverse of the base currents
• D. Difference of the base currents

74. CMRR means

• A. Common-mode rejection ratio
• B. The ratio of the differential voltage gain to common-mode voltage gain
• C. Both a and b
• D. The difference between the two base voltages

75. The typical dimension of a MOSFET in a single IC ship is

• A. 4 mils x 6.5 mils
• B. 2 mils x 12 mils
• C. 3 mils x 4.5 mils
• D. 1.5 mils x 3 mils

76. The maximum rate that an output voltage of an op-amp can change

• A. Slew rate
• B. CMRR
• C. Input offset voltage
• D. Tail current

77. The unwanted capacitance between connecting wires and ground.

• A. Summer capacitor
• B. Stray wiring capacitance
• C. Biasing capacitance
• D. Feedback capacitance

78. The typical dimension of a BJT in a single IC chip is

• A. 4 mils x 6.5 mils
• B. 2 mils x 12 mils
• C. 3 mils x 4.5 mils
• D. 1.5 mils x 3 mils

79. The typical dimension of a diode in a single IC chip is

• A. 4 mils x 6.5 mils
• B. 2 mils x 12 mils
• C. 3 mils x 4.5 mils
• D. 1.5 mils x 3 mils

80. Which of the items below is equivalent to a relaxation oscillator?

• A. Astable multivibrator
• B. Flip-flop
• C. Monostable multivibrator
• D. Bistable multivibrator

81. The unity gain frequency of an op-amp

• A. Is the frequency where the voltage gain of an op-amp is 1
• B. Indicates the highest usable frequency
• C. It equals the gain bandwidth product
• D. All of the above

82. If the base 10 is called decimal number system, then the base 12 is called

• A. Bidecimal number system
• B. Dodecimal number system
• C. Duodecimal number system
• D. All of the above

83. What is the principal method used in the fabrication of semiconductor devices for hybrid and monolithic ICs?

• A. Epitaxial growth
• B. Photolithographic process
• C. Isolation diffusion
• D. Planar technology

84. The gain reduction in operational amplifier is known as

• A. Roll-off
• B. Back-off
• C. Gain-off
• D. Attenuation

85. The rate of gain reduction in operational amplifiers

• A. 5 db per decade (-5db/decade)
• B. 6 db per decade (-6db/decade)
• C. 10 db per decade (-10db/decade)
• D. 20 db per decade (-20db/decade)

86. A capacitor inside an op-amp that prevents oscillations

• A. Compensating capacitor
• B. Limiting capacitor
• C. Biasing capacitor
• D. Coupling capacitor

87. A device that contains its own transistors, resistors and diodes

• A. Integrated circuit
• B. CMOS
• C. Logic gates
• D. All of the above

88. What provides a parameter specifying the maximum rate of change of the output when driven by a large step-input signal?

• A. Step rate
• B. Slew rate
• C. Step rate
• D. Dynamic rate

89. The absolute maximum rating for op-amps interval power dissipation is

• A. 500 mW
• B. 300 mW
• C. 200 mW
• D. 100 mW

90. What is the absolute maximum rating for an op-amps differential input voltage?

• A. ± 10 V
• B. ± 20 V
• C. ± 30 V
• D. ± 50 V

91. The amplifier CMRR of µA 741 op-amplifier is

• A. 60 dB
• B. 70 dB
• C. 80 dB
• D. 90 dB

92. The letter prefix LM identifies which of the following manufacturers?

• A. National semiconductor corporation
• B. Texas instrument
• C. Motorola
• D. Signetics

93. What is the letter prefix used by the Fairchild Semiconductor on their op-amp product?

• A. µA
• B. FS
• C. SG
• D. NE

94. Which of the following is not part of the three temperature range codes of op amps for commercial, industrial and military applications?

• A. -30 to 200ºC
• B. 0 to 70 ºC
• C. -25 to 85 ºC
• D. -55 to 125 ºC

95. What identifies the package style that houses the op amp chip?

• A. Letter suffix
• B. Letter prefix
• C. Circuit designator
• D. Military specification code

96. The package suffix code for ceramic dual-in-line is

• A. J
• B. D
• C. N
• D. P

97. The summing amplifier has two or more inputs, and its output voltage is proportional to the _____ of the algebraic sum of its input voltages.

• A. Positive
• B. Negative
• C. Reciprocal
• D. Inverse

98. When higher power ICs are needed, we can use

• A. Monolithic ICs
• B. Thin film ICs
• C. Thick film ICs
• D. Both b and c

99. In IC op-amps, one of the most important input characteristics is the _________ which is defined as the difference between the base currents.

• A. Input bias current
• B. Input offset current
• C. Total base current
• D. All of the choices

100. Monolithic ICs are

• A. Forms of discrete circuits
• B. Combination of thin-film and thick-film circuits
• C. Also called hybrid ICs
• D. Used for high power application

Complete List of MCQs in Electronics Engineering per topic

Series of Multiple Choice Questions in Electronics Engineering

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