Digital Electronics MCQs For GATE

Multiple Choice Questions On Digital Electronics For GATE pdf

As we know most of the competitive exams are Multiple Choice Questions (MCQ) based examination system and the main factor is to answer each question in a prescribed time on computer as Computer based test (CBT). So, if you want to crack any CBT Test practice as much as possible before the original test you are going to face.

Here below we are provided MCQ on Digital electronics and time allotted for each question is 30 seconds. After the allotted time, the question will be marked as un-attempt. If you solved Our digital electronics MCQ that we provide here will help you to pass the test in the first attempt.

Digital electronics mcq for gate

Multiple Choice Questions On Digital Electronics With Answers 

1. What is a digital-to-analog converter?

A) It stores digital data on the computer.

B) It converts alternating current (AC) into direct current (DC).

C) It converts electrical power into mechanical power.

D) It takes the digital data from an audio CD and converts it to a useful form.

Answer: D


 2.  SCR (Silicon Controlled Rectifier) is a ______________

A) Device with 3 junctions

B) Device with 2 junctions

C) Device with 1 junction

D) Device with 4 junctions

Answer: B


3. Which semiconductor device is not a current triggering device?

A) TRIAC

B) MOSFET

C) GTO

D) Thyristor

Answer: B


4. What is the binary subtraction of 101001 - 010110 =?

A) 010011

B) 100110

C) 011001

D) 010010

Answer: A


5. The inverter can be classified as_________

A) Power Inverter

B) Voltage source Inverter

C) Current source Inverter

D) Both option b and c

Answer: D


6. Temperature variation is a/an_________

A) Analog quantity

B) Digital quantity

C) Either Analog or Digital quantity

D) None of these

Answer: A


7. 1's complement of 1011001 is________

A) 0100111

B) 0101100

C) 0100110

D) 0110110

Answer: C


8. A ring counter with 5 flip flops will have________states.

A) 5

B) 10

C) 32

D) Infinite

Answer : A


9. In the expression A + BC, the total number of minterms will be__________

A) 2

B) 3

C) 4

D) 5

Answer : C


10. Which of the following is non-saturating?

A) TTL

B) CMOS

C) ECL

D) Both 1 and 2

Answer : C


11. The expression Y = pM (0, 1, 3, 4) is____________

A) POS

B) SOP

C) Hybrid

D) none of these

Answer : A


12. The greatest negative number which can be stored is 8 bit computer using 2’s complement arithmetic is_________

A) -256

B) -128

C) -255

D) -127

Answer: B


13. The basic storage element in a digital system is_____________

A) flipflop

B) counter

C) multiplexer

D) encoder

Answer : A


14. When an input signal 1 is applied to a NOT gate, the output is__________

A) 0

B) 1

C) Either 0 & 1

D) None of the above

Answer : A


15. The resolution of an n bit DAC with a maximum input of 5 V is 5 mV. The value of n is____________

A) 8

B) 9

C) 10

D) 11

Answer : C


16. An OR gate has 4 inputs. One input is high and the other three are low. The output is_____________

A) Low

B) High

C) alternately high and low

D) may be high or low depending on relative magnitude of inputs

Answer : B


17. A device which converts BCD to seven segments is called_____________

A) Encoder

B) Decoder

C) Multiplexer

D) None of these

Answer : B


18. A decade counter skips ___________

A) binary states 1000 to 1111

B) binary states 0000 to 0011

C) binary states 1010 to 1111

D) binary states 1111 to higher

Answer : C


19. Who invented Gray code?

A) Frank Gray

B) Dom Hofmann

C) Aryabhatta

D) None of the above

Answer: A


20. How many OR gates are used to made encoders? 

A) One

B) Two

C) Three

D) Four

Answer: B


21. The transducers converts _________

A) Non-electrical signals into electrical signals

B) Electrical signals into non-electrical signals

C) Electrical signals into electromagnetic waves

D) None of the above

Answer: A


22. Choose the odd one out

A) Watch

B) Calculator

C) Computer

D) Coal

Answer: D


23. The reverse transducer converts ___________

A) Non-electrical signals into electrical signals

B) Electrical signals into non-electrical signals

C) Electrical signals into electromagnetic waves

D) None of the above

Answer: B


24. The 8 bits is equal to the __________ bytes

A) One-byte

B) Two-bytes

C) Three-bytes

D) None of the above

Answer: A


25. What are the examples of un-weighted number systems and code?

A) Gray code

B) Excess-3 code

C) Both a and b

D) None of the above

Answer: A


26. All real-life signals are ________ in nature

A) Digital

B) Analog

C) Discrete

D) None of the above

Answer: B


27. What is the standard form of PIPO?

A) Parallel Input Parallel Output

B) Parallel Output Parallel Input

C) Positive Input Positive Output 

D) None of the above

Answer: A


28. The relationship between the input signals and the output signals is often summarized in a___________

A) truth logic

B) logic signal

C) truth table

D) multiple table

Answer: C


29. In digital electronics, the on state is often represented by a________

A) 1

B) 0

C) 5 V

D) 0 V

Answer: A


30. A x ? =

A) 0

B) 1

C) −∞

D) ∞

Answer: A


31. Which format requires fewer conductors?

A) Perpendicular

B) Parallel

C) Serial

D) Both are the same

Answer: C


32. The systematic reduction of logic circuits is accomplished by_________

A) Using a truth table

B) TTL logic

C) Symbolic reduction

D) Using Boolean algebra

Answer: D


33. A DAC changes _____

A) Digital data into an amplified signal

B) An analog signal into digital data

C) Digital data into an analog signal

D) All of the above

Answer: C


34. Most important advantage of an IC is its____________

A) Extremely high reliability

B) Reduced cost

C) Easy replacement is case of circuit failure

D) Low power consumption

Answer: A


35. A combinational logic circuit, which generates a particular binary word or number is____________

A) Multiplexer

B) Demultiplex

C) Encoder

D) Decoder

Answer: A


36. In the decimal numbering system, what is the MSD?

A) The last digit on the right

B) The digit to the right of the decimal point

C) The middle digit of a stream of numbers

D) The digit with the most weight

Answer: D


37. A flip-flop has____________

A) One stable state

B) Two stable states

C) No stable states

D) All of the above

Answer: B


38. Which of these following does not include in an ALU (Arithmetic Logic Unit)?

A) Adder

B) Subtractors

C) Multiplexer

S) None of the above

Answer: C


 39. A combinational circuit calculates the arithmetic sum in a parallel way. What is the name of the adder?

A) Sequential Adder

B) Parallel Adder

C) Serial Adder

D) Both A & B

Answer: B


40. How does a priority set?

A) The lower the subscript number, the higher the priority.

B) The higher the subscript number, the lower the priority.

C) The higher the subscript number, the higher the priority.

D) None of the above.

Answer: C


41. Which type of complement method is used for the decimal number system?

A) 10’s compliment

B) 8’s compliment

C) 9’s compliment

D) Both 1) and 3)

Answer: D


42. A decoder has an output of 2n. How many inputs does it consume?

A) n

B) 2n

C) 2n – 1

D) n-1

Answer: A


43. What is the lowest number of NAND gates required for a half subtractors?

A) Four

B) Five

C) Six

D) Seven

Answer: B


44. What is min-term?

A) Product of sum

B) Sum of product

C) Product of product

D) Sum of the sum

Answer: B


45. Which IC works as a multiplexer?

A) 74HA198

B) 74HC150

C) 74CH199

D) 74HC157

Answer: D


46. 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: A


47. 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: D


48. The generic array logic (GAL) device is ________

A) one-time programmable

B) reprogrammable

C) a cmos device

D) reprogrammable and a cmos device

Answer: B


49. 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: C


50. 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

Answer: D