Skip to content

GATE CS Digital Logic questions

Practise Digital Logic questions for GATE CS. Explore official PYQs and original subject-wise quizzes, check answers and view available solutions. Free, no sign-in.

Subject, topic, year and type filter the full library. Match any choice within a filter, and all selected filter categories. Search, source and sort apply to this page.

20 on this page
Official PYQ2024Digital LogicNumber Representations (Fixed and Floating Point)MCQ · 1 mark
Consider a system that uses 55 bits for representing signed integers in 22 's complement format. In this system, two integers AA and BB are represented as AA=0101001010 and BB=1101011010. Which one of the following operations will result in either an arithmetic overflow or an arithmetic underflow?
Official PYQ2024Digital LogicCombinational CircuitsMSQ · 1 mark
​​Consider the circuit shown below where the gates may have propagation delays. Assume that all signal transitions occur instantaneously and that wires have no delays. Which of the following statements about the circuit is/are CORRECT?
Official PYQ2024Digital LogicMinimization (K-Maps etc.)MSQ · 2 marks
Consider a Boolean expression given by F(X, Y, Z)=∑(3,5,6,7)\text{F(X, Y, Z)}=\sum(3,5,6,7). Which of the following statements is/are CORRECT?
Official PYQ2024Digital LogicCombinational CircuitsNAT · 2 marks
Consider a digital logic circuit consisting of three 22-to-11 multiplexers M1, M2\text{M1, M2}, and M3\text{M3} as shown below. X1\mathrm{X} 1 and X2\mathrm{X} 2 are inputs of M1\mathrm{M} 1. X3\text{X3} and X4\text{X4} are inputs of M2\text{M2}. A, B\text{A, B}, and C\text{C} are select lines of M1, M2\text{M1, M2}, and M3\text{M3}, …
Official PYQ2024Digital LogicBoolean AlgebraMSQ · 1 mark
​​​​For a Boolean variable xx, which of the following statements is/are FALSE?
Official PYQ2024Digital LogicNumber Representations (Fixed and Floating Point)MSQ · 2 marks
Which of the following is/are EQUAL to 224224 in radix - 55 (i.e., base - 55) notation?
Official PYQ2024Digital LogicMinimization (K-Maps etc.)MSQ · 2 marks
Consider 44-variable functions f1,f2,f3,f4f 1, f 2, f 3, f 4 expressed in sum-of-minterms form as given below. f1=∑(0,2,3,5,7,8,11,13)f2=∑(1,3,5,7,11,13,15)f3=∑(0,1,4,11)f4=∑(0,2,6,13)\begin{array}{l} f 1=\sum(0,2,3,5,7,8,11,13) \\ f 2=\sum(1,3,5,7,11,13,15) \\ f 3=\sum(0,1,4,11) \\ f 4=\sum(0,2,6,13) \end{array} With respect to the circuit given above, which of the following options is/are CORRECT?
Official PYQ2023Digital LogicCombinational CircuitsMCQ · 1 mark
The output of a 22-input multiplexer is connected back to one of its inputs as shown in the figure. Match the functional equivalence of this circuit to one of the following options.
Official PYQ2023Digital LogicNumber Representations (Fixed and Floating Point)NAT · 1 mark
A particular number is written as 132132 in radix-44 representation. The same number in radix-55 representation is _____________.
Official PYQ2023Digital LogicSequential CircuitsMCQ · 2 marks
Consider a sequential digital circuit consisting of T\mathrm{T} flip-flops and D\mathrm{D} flip-flops as shown in the figure. CLKIN\text{CLKIN} is the clock input to the circuit. At the beginning, Q1, Q2\text{Q1, Q2} and Q3\text{Q3} have values 0,10,1 and 1,1, respectively. Which one of the given values of (Q1, Q2, Q3)\text{(Q1, Q2, Q3)} can NEVER\text{NEVER} …
Official PYQ2023Digital LogicCombinational CircuitsMCQ · 2 marks
A Boolean digital circuit is composed using two 44-input multiplexers (M1 and M2)\text{(M1 and M2)} and one 22-input multiplexer (M3)\text{(M3)} as shown in the figure. X0-X7\text{X0-X7} are the inputs of the multiplexers M1 and M2\text{M1 and M2} and could be connected to either 00 or 1.1. The select lines of the multiplexers are connected to Boolean …
Official PYQ2023Digital LogicNumber Representations (Fixed and Floating Point)MCQ · 2 marks
Consider the IEEE-754\textsf{IEEE-754} single precision floating point numbers P=0xC1800000\text{P} = \textsf{0xC1800000} and Q=0x3F5C2EF4.\text{Q} = \textsf{0x3F5C2EF4}. Which one of the following corresponds to the product of these numbers (i.e., P×Q),(\text{i.e., P} \times \mathrm{Q} ), represented in the IEEE-754\textsf{IEEE-754} single precision format?
Official PYQ2022Digital LogicNumber Representations (Fixed and Floating Point)MCQ · 1 mark
Let R1\text{R1} and R2\text{R2} be two 4–bit4 – \text{bit} registers that store numbers in 2’s2\text{’s} complement form. For the operation R1 + R2,\text{R1 + R2}, which one of the following values of R1\text{R1} and R2\text{R2} gives an arithmetic overflow?
Official PYQ2022Digital LogicCombinational CircuitsMCQ · 2 marks
Consider a digital display system (DDS)\text{(DDS)} shown in the figure that displays the contents of register X.\text{X}. A 16–bit16 – \text{bit} code word is used to load a word in X,\text{X}, either from S\text{S} or from R.\text{R}. S\text{S} is a 1024−1024-word memory segment and R\text{R} is a 32−32-word register file. Based on the value of …
Official PYQ2022Digital LogicNumber Representations (Fixed and Floating Point)MCQ · 2 marks
Consider three floating point numbers A, B\textit{A, B} and C\textit{C} stored in registers RA,RB\text{R}_{\text{A}}, \text{R}_{\text{B}} and RC,\text{R}_{\text{C}}, respectively as per IEEE-754\textsf{IEEE-754} single precision floating point format. The 32-bit\text{32-bit} content stored in these registers (in hexadecimal form)\text{(in hexadecimal form)} are as follows. …
Official PYQ2021Digital LogicNumber Representations (Fixed and Floating Point)MCQ · 1 mark
Let the representation of a number in base 33 be 210210. What is the hexadecimal representation of the number?
Official PYQ2021Digital LogicNumber Representations (Fixed and Floating Point)NAT · 1 mark
Consider the following representation of a number in IEEE 754\text{IEEE 754} single-precision floating point format with a bias of 127127.S:1E:  10000001F:  11110000000000000000000S: 1\quad\quad E:\; 10000001\quad\quad F:\;11110000000000000000000 Here S,  ES, \;E and FF denote the sign, exponent, and fraction components of the floating point representation. The decimal value corresponding to the …
Official PYQ2021Digital LogicSequential CircuitsMCQ · 2 marks
Consider a 33-bit counter, designed using TT flip-flops, as shown below: Assuming the initial state of the counter given by PQR\text{PQR} as 000000, what are the next three states?
Official PYQ2021Digital LogicBoolean AlgebraMSQ · 2 marks
Consider the following Boolean expression. F=(X+Y+Z)(X‾+Y)(Y‾+Z)F=(X+Y+Z)(\overline X +Y)(\overline Y +Z) Which of the following Boolean expressions is/are equivalent to F‾\overline F (complement of FF)?
Official PYQ2021Digital LogicNumber Representations (Fixed and Floating Point)MCQ · 1 mark
The format of the single-precision floating point representation of a real number as per the IEEE 754\text{IEEE 754} standard is as follows: signexponentmantissa\begin{array}{|c|c|c|} \hline \text{sign} & \text{exponent} & \text{mantissa} \\ \hline \end{array} Which one of the following choices is correct with respect to the smallest normalized positive number …