Multiple Choice Questions and Correct Answers :-
1. Any number with an exponent of zero is equal to:
A.zero
B.one
C.that number
D.ten
Correct Answers : Option B
2. In the decimal numbering system, what is the MSD?
A.The middle digit of a stream of numbers
B.The digit to the right of the decimal point
C.The last digit on the right
D.The digit with the most weight
Correct Answers : Option D
3. Which of the following statements does NOT describe an advantage of digital technology?
A.The values may vary over a continuous range.
B.The circuits are less affected by noise.
C.The operation can be programmed.
D.Information storage is easy.
Correct Answers : Option A
4. The generic array logic (GAL) device is ________.
A.one-time programmable
B.reprogrammable
C.a CMOS device
D.reprogrammable and a CMOS device
Correct Answers : Option B
5. The range of voltages between VL(max) and VH(min) are ________.
A.unknown
B.unnecessary
C.unacceptable
D.between 2 V and 5 V
Correct Answers : Option C
6. What is a digital-to-analog converter?
A.It takes the digital information from an audio CD and converts it to a usable form.
B.It allows the use of cheaper analog techniques, which are always simpler.
C.It stores digital data on a hard drive.
D.It converts direct current to alternating current.
Correct Answers : Option A
7. What are the symbols used to represent digits in the binary number system?
A.0,1
B.0,1,2
C.0 through 8
D.1,2
Correct Answers : Option A
8. A full subtracter circuit requires ________.
A.two inputs and two outputs
B.two inputs and three outputs
C.three inputs and one output
D.three inputs and two outputs
Correct Answers : Option D
9. The output of an AND gate is LOW ________.
A.all the time
B.when any input is LOW
C.when any input is HIGH
D.when all inputs are HIGH
Correct Answers : Option B
10. Give the decimal value of binary 10010.
A.610
B.910
C.1810
D.2010
Correct Answers : Option C
11. Parallel format means that:
A.each digital signal has its own conductor.
B.several digital signals are sent on each conductor.
C.both binary and hexadecimal can be used.
D.no clock is needed.
Correct Answers : Option A
12. A decoder converts ________.
A.noncoded information into coded form
B.coded information into noncoded form
C.HIGHs to LOWs
D.LOWs to HIGHs
Correct Answers : Option B
13. A DAC changes ________.
A.an analog signal into digital data
B.digital data into an analog signal
C.digital data into an amplified signal
D.none of the above
Correct Answers : Option B
14. The output of a NOT gate is HIGH when ________.
A.the input is LOW
B.the input is HIGH
C.the input changes from LOW to HIGH
D.voltage is removed from the gate
Correct Answers : Option A
15. The output of an OR gate is LOW when ________.
A.all inputs are LOW
B.any input is LOW
C.any input is HIGH
D.all inputs are HIGH
Correct Answers : Option A
16. Which of the following is not an analog device?
A.Thermocouple
B.Current flow in a circuit
C.Light switch
D.Audio microphone
Correct Answers : Option C
17. A demultiplexer has ________.
A.one data input and a number of selection inputs, and they have several outputs
B.one input and one output
C.several inputs and several outputs
D.several inputs and one output
Correct Answers : Option A
18. A flip-flop has ________.
A.one stable state
B.no stable states
C.two stable states
D.none of the above
Correct Answers : Option C
19. Digital signals transmitted on a single conductor (and a ground) must be transmitted in:
A.slow speed.
B.parallel.
C.analog.
D.serial.
Correct Answers : Option D
20. In a certain digital waveform, the period is four times the pulse width. The duty cycle is ________.
A.0%
B.25%
C.50%
D.100%
Correct Answers : Option B
21. Select the statement that best describes the parity method of error detection:
A.Parity checking is best suited for detecting double-bit errors that occur during the transmission of codes from one location to another.
B.Parity checking is not suitable for detecting single-bit errors in transmitted codes.
C.Parity checking is best suited for detecting single-bit errors in transmitted codes.
D.Parity checking is capable of detecting and correcting errors in transmitted codes.
Correct Answers : Option C
22. A logic circuit that provides a HIGH output for both inputs HIGH or both inputs LOW is a(n):
A.Ex-NOR gate
B.OR gate
C.Ex-OR gate
D.NAND gate
Correct Answers : Option A
23. A logic circuit that provides a HIGH output if one input or the other input, but not both, is HIGH, is a(n):
A.Ex-NOR gate
B.OR gate
C.Ex-OR gate
D.NAND gate
Correct Answers : Option C
24. Identify the type of gate below from the equation
A.Ex-NOR gate
B.OR gate
C.Ex-OR gate
D.NAND gate
Correct Answers : Option C
25. How is odd parity generated differently from even parity?
A.The first output is inverted.
B.The last output is inverted.
Correct Answers : Option B
26. Parity systems are defined as either________ or ________ and will add an extra ________ tothe digital information being transmitted.
A.positive, negative, byte
B.odd, even, bit
C.upper, lower, digit
D.on, off, decimal
Correct Answers : Option B
27. Which type of gate can be used to add two bits?
A.Ex-OR
B.Ex-NOR
C.Ex-NAND
D.NOR
Correct Answers : Option A
28. Why is an exclusive-NOR gate also called an equality gate?
A.The output is false if the inputs are equal.
B.The output is true if the inputs are opposite.
C.The output is true if the inputs are equal.
Correct Answers : Option C
29. Show from the truth table how an exclusive-OR gate can be used to invert the data on one input if the other input is a special control function.
A.Using A as the control, when A = 0, X is the same as B. When A = 1, X is the same as B.
B.Using A as the control, when A = 0, X is the same as B. When A = 1, X is the inverse of B.
C.Using A as the control, when A = 0, X is the inverse of B. When A = 1, X is the same as B.
D.Using A as the control, when A = 0, X is the inverse of B. When A = 1, X is the inverse of B.
Correct Answers : Option B
30. Determine odd parity for each of the following data words:
1011101 11110111 1001101
A.P = 1, P = 1, P = 0
B.P = 0, P = 0, P = 0
C.P = 1, P = 1, P = 1
D.P = 0, P = 0, P = 1
Correct Answers : Option D
31. In a flash analog-to-digital converter, the output of each comparator is connected to an input of a ________.
A.decoder
B.priority encoder
C.multiplexer
D.demultiplexer
Correct Answers : Option B
32.Which term applies to the maintaining of a given signal level until the next sampling?
A.Holding
B.Aliasing
C.Shannon frequency sampling
D.”Stair-stepping”
Correct Answers : Option A
33. An op-amp has very ________.
A.high voltage gain
B.high input impedance
C.low output impedance
D.all of the above
Correct Answers : Option D
34. For a 4-bit DAC, the least significant bit (LSB) is ________.
A.6.25% of full scale
B.0.625% of full scale
C.12% of full scale
D.1.2% of full scale
Correct Answers : Option A
35. The dual-slope analog-to-digital converter finds extensive use in ________.
A.digital voltmeters
B.function generators
C.frequency counters
D.all of the above
Correct Answers : Option D
36. The ADC0804 is an example of a ________.
A.single-slope analog-to-digital converter
B.dual-slope analog-to-digital converter
C.digital-ramp analog-to-digital converter
D.successive-approximation analog-to-digital converter
Correct Answers : Option D
37. In a digital representation of voltages using an 8-bit binary code, how many values can be defined?
A.16
B.64
C.128
D.256
Correct Answers : Option D
38. A 4-bit R/2R ladder digital-to-analog converter uses ________.
A.one resistor value
B.two resistor values
C.three resistor values
D.four resistor values
Correct Answers : Option B
39. A binary-weighted-input digital-to-analog converter has a feedback resistor, Rf, of 12 k. If 50 A of current is through the resistor, voltage out of the circuit is ________.
A.0.6 V
B.–0.6 V
C.0.1 V
D.–0.1 V
Correct Answers : Option B
40. The resolution of a 6-bit DAC is ________.
A.63%
B.64%
C.15.9%
D.1.59%
Correct Answers : Option D
41. How are unwanted frequencies removed prior to digital conversion?
A.Pre-filters
B.Digital signal processing
C.Sample-and-hold circuits
D.All of the above
Correct Answers : Option A
42. Which type of programming is typically used for digital signal processors?
A.Assembly language
B.Machine language
C.C
D.None of the above
Correct Answers : Option A
43. Which of the following best defines Nyquist frequency?
A.The frequency of resonance for the filtering circuit
B.The second harmonic
C.The lower frequency limit of sampling
D.The highest frequency component of a given analog signal
Correct Answers : Option D
44. Which is not an A/D conversion error?
A.Differential nonlinearity
B.Missing code
C.Incorrect code
D.Offset
Correct Answers : Option A
45.Settling time is normally defined as the time it takes a DAC to settle within ________.
A.1/8 LSB of its final value when a change occurs in the input code
B.1/4 LSB of its final value when a change occurs in the input code
C.1/2 LSB of its final value when a change occurs in the input code
D.1 LSB of its final value when a change occurs in the input code
Correct Answers : Option C
46.Determine the output frequency for a frequency division circuit that contains 12 flip-flops with an input clock frequency of 20.48 MHz.
A.10.24 kHz
B.5 kHz
C.30.24 kHz
D.15 kHz
Correct Answers : Option B
47. Which statement BEST describes the operation of a negative-edge-triggered D flip-flop?
A.The logic level at the D input is transferred to Q on NGT of CLK.
B.The Q output is ALWAYS identical to the CLK input if the D input is HIGH.
C.The Q output is ALWAYS identical to the D input when CLK = PGT.
D.The Q output is ALWAYS identical to the D input.
Correct Answers : Option A
48. Propagation delay time, tPLH, is measured from the ________.
A.triggering edge of the clock pulse to the LOW-to-HIGH transition of the output
B.triggering edge of the clock pulse to the HIGH-to-LOW transition of the output
C.preset input to the LOW-to-HIGH transition of the output
D.clear input to the HIGH-to-LOW transition of the output
Correct Answers : Option A
49. How is a J-K flip-flop made to toggle?
A.J = 0, K = 0
B.J = 1, K = 0
C.J = 0, K = 1
D.J = 1, K = 1
Correct Answers : Option D
50. How many flip-flops are in the 7475 IC?
A.1
B.2
C.4
D.8
Correct Answers : Option C
51. How many flip-flops are required to produce a divide-by-128 device?
A.1
B.4
C.6
D.7
Correct Answers : Option D
52. The ________ circuit overcomes the problem of switching caused by jitter on the inputs.
A.astable multivibrator
B.monostable multivibrator
C.bistable multivibrator
D.Schmitt trigger
Correct Answers : Option D
53. Why would a delay gate be needed for a digital circuit?
A.A delay gate is never needed.
B.to provide for setup times
C.to provide for hold times
D.to provide for setup times and hold times
Correct Answers : Option D
54. An optocoupler is an integrated circuit with an LED and a zener diode encased in the same package.
A.True
B.False
Correct Answers : Option B
55. A Schmitt trigger has VT+ = 2.0 V and VT– = 1.2 V. What is the hysteresis voltage of the Schmitt trigger?
A.0.4 volt
B.0.6 volt
C.0.8 volt
D.1.2 volts
Correct Answers : Option C
56. Which of the following circuit parameters would be most likely to limit the maximum operating frequency of a flip-flop?
A.setup and hold time
B.clock pulse HIGH and LOW time
C.propagation delay time
D.clock transition time
Correct Answers : Option C
57. What is the result of taking more samples during the quantization process?
A.More errors in the analog-to-digital conversion
B.More bit requirements
C.More accurate signal representation
D.More bit requirements and more accurate signal representation
Correct Answers : Option D
58. Which A/D conversion method has a fixed conversion time?
A.Single-slope analog-to-digital converter
B.Dual-slope analog-to-digital converter
C.Digital-ramp analog-to-digital converter
D.Successive-approximation analog-to-digital converter
Correct Answers : Option D
18. Which is a typical application of digital signal processing?
A.Noise elimination
B.Music signal processing
C.Image processing
D.All of the above
Correct Answers : Option D
60. If a DAC has a full-scale, or maximum, output of 12 V and accuracy of 0.1%, then the maximum error for any output voltage is ________.
A.12 V
B.120 mV
C.12 mV
D.0 V
Correct Answers : Option C
70. What do we call the manipulation of an analog signal in a digital domain?
A.Analog-to-digital conversion
B.Digital-to-analog conversion
C.Digital signal processing
D.Signal filtering
Correct Answers : Option B
71. How many address bits are needed to select all memory locations in the 2118 16K × 1 RAM?
A.8
B.10
C.14
D.16
Correct Answers : Option C
72. The check sum method of testing a ROM:
A.indicates if the data in more than one memory location is incorrect.
B.provides a means for locating and correcting data errors in specific memory locations.
C.allows data errors to be pinpointed to a specific memory location.
D.simply indicates that the contents of the ROM are incorrect.
Correct Answers : Option D
73. Refer to the given figures (a) and (b). A logic analyzer is used to check the circuit in figure (a) and displays the waveforms shown in figure (b). The actual analyzer display shows all four data outputs, Q0-Q3. The analyzer’s cursor is placed at position X and all four of the data output lines show a LOW level output. What is wrong, if anything, with the circuit?
A.Nothing is wrong, according to the display. The outputs are in the open state and should show zero output voltage.
B.The circuit is in the READ mode and the outputs, Q0-Q3, should reflect the contents of the memory at that address. The chip is defective; replace the chip.
C.The circuit is in the mode and should be writing the contents of the selected address to Q0–Q3.
D.The Q0–Q3 lines can be either LOW or HIGH, since the chip is in the tristate mode in which case their level is unpredictable.
Correct Answers : Option D
74. What is the meaning of RAM, and what is its primary role?
A.Readily Available Memory; it is the first level of memory used by the computer in all of its operations.
B.Random Access Memory; it is memory that can be reached by any sub- system within a computer, and at any time.
C.Random Access Memory; it is the memory used for short-term temporary data storage within the computer.
D.Resettable Automatic Memory; it is memory that can be used and then automatically reset, or cleared, after being read from or written to.
Correct Answers : Option C
75. The storage element for a static RAM is the ________.
A.diode
B.resistor
C.capacitor
D.flip-flop
Correct Answers : Option D
76. In a DRAM, what is the state of R/W during a read operation?
A.Low
B.High
C.Hi-Z
D.None of the above
Correct Answers : Option B
77. The condition occurring when two or more devices try to write data to a bus simultaneously is called ________.
A.address decoding
B.bus contention
C.bus collisions
D.address multiplexing
Correct Answers : Option B
78. The difference between a PLA and a PAL is:
A.The PLA has a programmable OR plane and a programmable AND plane, while the PAL only has a programmable AND plane.
B.The PAL has a programmable OR plane and a programmable AND plane, while the PLA only has a programmable AND plane.
C.The PAL has more possible product terms than the PLA.
D.PALs and PLAs are the same thing.
Correct Answers : Option A
79. ALM is the acronym for ________.
A.Array Logic Matrix
B.Arithmetic Logic Module
C.Asynchronous Local Modulator
D.Adaptive Logic Module
Correct Answers : Option D
80. The GAL16V8 has:
A.16 dedicated inputs.
B.8 special function pins.
C.8 pins that are used as inputs or outputs.
D.All of the above
Correct Answers : Option C
81. PALs tend to execute ________ logic.
A.SAP
B.SOP
C.PLA
D.SPD
Correct Answers : Option B
82. How many pins are in an EDF10K70 package?
A.70
B.140
C.240
D.532
Correct Answers : Option C
83. Convert hexadecimal value 16 to decimal.
A.2210
B.1610
C.1010
D.2010
Correct Answers : Option A
84. Convert the following decimal number to 8-bit binary.
A.101110112
B.110111012
C.101111012
D.101111002
Correct Answers : Option A
85. Convert binary 111111110010 to hexadecimal.
A.EE216
B.FF216
C.2FE16
D.FD216
Correct Answers : Option B
86. Convert the following binary number to decimal.
010112
A.11
B.35
C.15
D.10
Correct Answers : Option A
87. Convert the binary number 1001.00102 to decimal.
A.90.125
B.9.125
C.125
D.12.5
Correct Answers : Option B
88. Decode the following ASCII message.
10100111010100101010110001001011001
01000001001000100000110100101000100
A.STUDYHARD
B.STUDY HARD
C.stydyhard
D.study hard
Correct Answers : Option B
89. The voltages in digital electronics are continuously variable.
A.True
B.False
Correct Answers : Option B
90. One hex digit is sometimes referred to as a(n):
A.byte
B.nibble
C.grouping
D.instruction
Correct Answers : Option B
91.Which of the following is the most widely used alphanumeric code for computer input and output?
A.Gray
B.ASCII
C.Parity
D.EBCDIC
Correct Answers : Option B
92. If a typical PC uses a 20-bit address code, how much memory can the CPU address?
A.20 MB
B.10 MB
C.1 MB
D.580 MB
Correct Answers : Option C
93. Convert 59.7210 to BCD.
A.111011
B.01011001.01110010
C.1110.11
D.0101100101110010
Correct Answers : Option B
94. Convert 8B3F16 to binary.
A.35647
B.011010
C.1011001111100011
D.1000101100111111
Correct Answers : Option D
95. Which is typically the longest: bit, byte, nibble, word?
A.Bit
B.Byte
C.Nibble
D.Word
Correct Answers : Option D
96. Assign the proper odd parity bit to the code 111001.
A.1111011
B.1111001
C.0111111
D.0011111
Correct Answers : Option B
97. Convert decimal 64 to binary.
A.01010010
B.01000000
C.00110110
D.01001000
Correct Answers : Option B
98. Convert hexadecimal value C1 to binary.
A.11000001
B.1000111
C.111000100
D.111000001
Correct Answers : Option A
99. Convert the following octal number to decimal.
178
A.51
B.82
C.57
D.15
Correct Answers : Option D
100. Convert the following binary number to octal.
0101111002
A.1728
B.2728
C.1748
D.2748
Correct Answers : Option D