Explore topic-wise MCQs in Digital Electronics.

This section includes 139 Mcqs, each offering curated multiple-choice questions to sharpen your Digital Electronics knowledge and support exam preparation. Choose a topic below to get started.

101.

Temperature variation is normally an analog quantity.

A. 1
B.
Answer» B.
102.

A decoder converts ________.

A. noncoded information into coded form
B. coded information into noncoded form
C. HIGHs to LOWs
D. LOWs to HIGHs
Answer» C. HIGHs to LOWs
103.

In a positive logic system, the logic LOW could be between 0 V and 0.8 V.

A. 1
B.
C. 1
D.
Answer» B.
104.

The frequency of a pulse train is 2 kHz. The pulse period is ________.

A. 5 ms
B. 50 ms
C. 500 s
D. 2 s
Answer» D. 2 s
105.

The holes through a PC board are ________.

A. smaller with SMT than with through-hole mounting
B. larger with SMT than with through-hole mounting
C. the same size as with through-hole mounting
D. usually unnecessary
Answer» D. usually unnecessary
106.

In a typical digital system, Logic 0 is 0V–0.8V, and Logic 1 is ________.

A. 2–5V
B. 2.5–5V
C. 3.0–5.5V
D. 3.5–5.5V
Answer» B. 2.5‚Äì5V
107.

An ADC is an analog-to-digital converter.

A. 1
B.
C. 1
D.
Answer» B.
108.

The systems shown in the given figure transfer data ________.

A. serially
B. sequentially
C. in parallel
D. both serially and sequentially
Answer» E.
109.

A continually variable, proportional indicator is a(n) ________ representation.

A. decimal
B. digital
C. unconstitutional
D. analog
Answer» E.
110.

Which format requires fewer conductors?

A. Parallel
B. Serial
C. Both are the same
D. Cannot tell
Answer» C. Both are the same
111.

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
Answer» C. when any input is HIGH
112.

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
Answer» B. 0,1,2
113.

The invalid range for an input to TTL logic is from ________.

A. 0 to 0.8 V
B. 1.2 to 1.6 V
C. 0.8 to 2.0 V
D. 2.0 to 5.0 V
Answer» D. 2.0 to 5.0 V
114.

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
Answer» C. digital data into an amplified signal
115.

What is one relative disadvantage of serial transfer?

A. It requires too many conductors.
B. Its interconnect system is complex.
C. It is slow.
D. It can only be used over very short distances.
Answer» D. It can only be used over very short distances.
116.

An encoder converts ________.

A. noncoded information into coded form
B. coded information into noncoded form
C. HIGHs to LOWs
D. LOWs to HIGHs
Answer» B. coded information into noncoded form
117.

Convert the fractional binary number 10010.0100 to decimal.

A. 24.5
B. 18.25
C. 18.4
D. 16.25
Answer» C. 18.4
118.

Telecommunications systems do not use digital techniques.

A. 1
B.
C. 1
D.
Answer» C. 1
119.

A pulse has a period of 15 ms. Its frequency is ________.

A. 6.66 Hz
B. 66.66 Hz
C. 666.66 Hz
D. 15 Hz
Answer» C. 666.66 Hz
120.

Which of the following is a semiconductor memory?

A. RAM
B. MAR
C. CD-ROM
D. CD
Answer» B. MAR
121.

Memory devices store binary data.

A. 1
B.
C. 1
D.
Answer» B.
122.

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
Answer» B. the input is HIGH
123.

A classification of ICs with complexities of 12 to 100 equivalent gates on a chip is known as ________.

A. SSI
B. MSI
C. LSI
D. VLSI
Answer» C. LSI
124.

Which of the following is not an analog device?

A. Thermocouple
B. Current flow in a circuit
C. Light switch
D. Audio microphone
Answer» D. Audio microphone
125.

What kind of logic device or circuit is used to store information?

A. Counter
B. Register
C. Inverter
D. Buffer
Answer» C. Inverter
126.

Which format can send several bits of information faster?

A. Parallel
B. Serial
C. Both are the same
D. Cannot tell
Answer» B. Serial
127.

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
Answer» E.
128.

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.
Answer» B. several digital signals are sent on each conductor.
129.

The voltage levels used to represent binary values (0 and 1) in a digital system are nearly equal in value.

A. 1
B.
C. 1
D.
Answer» C. 1
130.

The rise time is the time it takes a pulse to go from ________.

A. the base line to the maximum HIGH voltage
B. 10% of the pulse amplitude to the maximum HIGH voltage
C. the base line to 90% of the pulse amplitude
D. 10% of the pulse amplitude to 90% of the pulse amplitude
Answer» E.
131.

The range of voltages between VL(max) and VH(min) are ________.

A. unknown
B. unnecessary
C. unacceptable
D. between 2 V and 5 V
Answer» D. between 2 V and 5 V
132.

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.
Answer» B. It allows the use of cheaper analog techniques, which are always simpler.
133.

Convert the fractional decimal number 6.75 to binary.

A. 111.11
B. 110.101
C. 110.11
D. 110.011
Answer» D. 110.011
134.

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.
Answer» B. The circuits are less affected by noise.
135.

In positive logic, ________.

A. a HIGH = 1, a LOW = 0
B. a LOW = 1, a HIGH = 0
C. only HIGHs are present
D. only LOWs are present
Answer» B. a LOW = 1, a HIGH = 0
136.

The generic array logic (GAL) device is ________.

A. one-time programmable
B. reprogrammable
C. a CMOS device
D. reprogrammable and a CMOS device
Answer» C. a CMOS device
137.

How many binary bits are necessary to represent 748 different numbers?

A. 9
B. 7
C. 10
D. 8
Answer» D. 8
138.

Digital systems have ________.

A. one state
B. two states
C. three states
D. four states
Answer» C. three states
139.

Any number with an exponent of zero is equal to:

A. zero
B. one
C. that number
D. ten
Answer» C. that number