50+ Top Digital Design Multiple Choice Questions with Answers
What is the fundamental building block of digital circuits?
a) Transistor.
b) Diode.
c) Capacitor.
d) Resistor.
Answer: a) Transistor
What does the term “logic level” represent in digital electronics?
a) The voltage range used to represent binary values
b) The maximum current a digital circuit can handle
c) The speed at which a digital circuit operates
d) The logic gate used in a digital circuit
Answer: a) The voltage range used to represent binary values
Which number system is commonly used in digital electronics?
a) Binary
b) Decimal
c) Hexadecimal
d) Octal
Answer: a) Binary
In binary, what does a “1” represent?
a) High voltage
b) Low voltage
c) Ground
d) Open circuit
Answer: a) High voltage
How many bits are in a byte?
a) 4
b) 8
c) 16
d) 32
Answer: b) 8
Which logic gate performs the Boolean AND operation?
a) OR gate
b) NOT gate
c) NAND gate
d) AND gate
Answer: d) AND gate
The output of an OR gate is HIGH when:
a) All inputs are LOW
b) Any input is HIGH
c) All inputs are HIGH
d) None of the inputs are connected
Answer: b) Any input is HIGH
What is the complement of a binary number 1010?
a) 1010
b) 0101
c) 1101
d) 0110
Answer: b) 0101
Which logic gate is an inverted OR gate?
a) OR gate
b) NOT gate
c) NAND gate
d) AND gate
Answer: c) NAND gate
A half-adder adds:
a) Two binary numbers and a carry-in
b) Two binary numbers without a carry-in
c) Two decimal numbers and a carry-in
d) Two decimal numbers without a carry-in
Answer: b) Two binary numbers without a carry-in
How many input combinations are possible in a 2-input logic gate?
a) 2
b) 3
c) 4
d) 8
Answer: c) 4
Which logic gate is equivalent to an inverted AND gate?
a) OR gate
b) NOT gate
c) NAND gate
d) XOR gate
Answer: c) NAND gate
The binary number “1011” is equivalent to which decimal number?
a) 5
b) 8
c) 10
d) 11
Answer: d) 11
Which logic gate is used for addition in binary arithmetic?
a) AND gate
b) OR gate
c) XOR gate
d) NAND gate
Answer: c) XOR gate
What is the result of the binary subtraction: 1001 – 0110?
a) 0011
b) 0101
c) 1010
d) 1101
Answer: a) 0011
What does TTL stand for in digital electronics?
a) Time To Learn
b) Transistor-Transistor Logic
c) Time To Live
d) Transistor-Transformer Logic
Answer: b) Transistor-Transistor Logic
Which logic gate is used to perform binary multiplication?
a) AND gate
b) OR gate
c) XOR gate
d) NAND gate
Answer: a) AND gate
What is the function of a decoder in digital circuits?
a) Performs arithmetic operations
b) Converts binary codes into a more complex format
c) Converts binary codes into decimal numbers
d) Converts binary codes into their respective outputs
Answer: d) Converts binary codes into their respective outputs
A 3-input OR gate will output HIGH if:
a) All inputs are LOW
b) Any input is HIGH
c) All inputs are HIGH
d) Only one input is HIGH
Answer: b) Any input is HIGH
The hexadecimal number “A3” is equivalent to which binary number?
a) 10100100
b) 11000011
c) 10100011
d) 10110100
Answer: c) 10100011
What does the term “propagation delay” mean in digital circuits?
a) The time taken to complete one clock cycle
b) The time taken for a signal to propagate through a circuit
c) The time taken for a digital circuit to power up
d) The time taken for a logic gate to change its state
Answer: b) The time taken for a signal to propagate through a circuit
Which logic gate is used for creating a digital memory element?
a) AND gate
b) OR gate
c) Flip-flop
d) XOR gate
Answer: c) Flip-flop
What is the output of an XOR gate when both inputs are the same?
a) High
b) Low
c) Floating
d) Indeterminate
Answer: b) Low
Which logic gate is used in binary subtraction?
a) AND gate
b) OR gate
c) XOR gate
d) NAND gate
Answer: c) XOR gate
The binary number “1110” is equivalent to which decimal number?
a) 5
b) 9
c) 12
d) 13
Answer: d) 13
What is the result of the binary addition: 1011 + 0101?
a) 10010
b) 1110
c) 11010
d) 100
Answer: c) 11010
What does CMOS stand for in digital electronics?
a) Complementary Metal-Oxide Semiconductor
b) Continuous Metal-Oxide Semiconductor
c) Conventional Metal-Oxide Semiconductor
d) Complimentary Mode-Oscillator System
Answer: a) Complementary Metal-Oxide Semiconductor
Which logic gate is used to perform binary division?
a) AND gate
b) OR gate
c) XOR gate
d) NAND gate
Answer: d) NAND gate
The octal number “36” is equivalent to which binary number?
a) 011101
b) 111110
c) 011110
d) 111001
Answer: c) 011110
How many input combinations are possible in a 3-input logic gate?
a) 6
b) 7
c) 8
d) 9
Answer: c) 8
Which logic gate is used as a basic memory cell in RAM?
a) AND gate
b) OR gate
c) Flip-flop
d) XOR gate
Answer: c) Flip-flop
The binary number “1101” is equivalent to which decimal number?
a) 5
b) 9
c) 12
d) 13
Answer: d) 13
Which logic gate is used for creating a counter in digital circuits?
a) AND gate
b) OR gate
c) Flip-flop
d) XOR gate
Answer: c) Flip-flop
In a 4-bit binary system, what is the highest decimal number that can be represented?
a) 7
b) 8
c) 15
d) 16
Answer: c) 15
What is the output of a NOR gate when both inputs are LOW?
a) High
b) Low
c) Floating
d) Indeterminate
Answer: a) High
Which logic gate is used for binary comparator circuits?
a) AND gate
b) OR gate
c) Flip-flop
d) XOR gate
Answer: d) XOR gate
The binary number “100110” is equivalent to which octal number?
a) 56
b) 46
c) 32
d) 22
Answer: b) 46
What is the result of the binary division: 1100 ÷ 0110?
a) 10
b) 11
c) 100
d) 101
Answer: b) 11
Which logic gate is used to perform binary exponentiation?
a) AND gate
b) OR gate
c) XOR gate
d) NAND gate
Answer: c) XOR gate
What does the term “fan-out” mean in digital electronics?
a) The number of inputs a logic gate can handle
b) The number of outputs a logic gate can handle
c) The maximum speed of a digital circuit
d) The power consumption of a digital circuit
Answer: b) The number of outputs a logic gate can handle
The binary number “101010” is equivalent to which hexadecimal number?
a) 2A
b) 54
c) 3A
d) 2E
Answer: a) 2A
What is the output of a NOT gate when the input is HIGH?
a) High
b) Low
c) Floating
d) Indeterminate
Answer: b) Low
Which logic gate is used for creating a multiplexer in digital circuits?
a) AND gate
b) OR gate
c) Flip-flop
d) XOR gate
Answer: d) XOR gate
The binary number “11111111” is equivalent to which decimal number?
a) 63
b) 127
c) 255
d) 512
Answer: c) 255
What is the result of the binary multiplication: 1101 × 0110?
a) 101110
b) 10101
c) 100100
d) 10010
Answer: c) 100100
In a digital circuit, what does the term “clock” represent?
a) A logic gate used for synchronization
b) A pulse signal that synchronizes circuit operations
c) A type of flip-flop
d) A logic gate used for counting
Answer: b) A pulse signal that synchronizes circuit operations
Which logic gate is used for creating a demultiplexer in digital circuits?
a) AND gate
b) OR gate
c) Flip-flop
d) XOR gate
Answer: a) AND gate
The binary number “1110011” is equivalent to which octal number?
a) 123
b) 71
c) 63
d) 43
Answer: c) 63
What is the result of the binary exponentiation: 1010 ^ 0101?
a) 1010
b) 0101
c) 1111
d) 10000
Answer: c) 1111
Which logic gate is used in a digital circuit to store one bit of data?
a) AND gate
b) OR gate
c) Flip-flop
d) XOR gate
Answer: c) Flip-flop