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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.

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Official PYQ2026Digital LogicNumber Representations (Fixed and Floating Point)MSQ · 1 mark
Consider the 88 -bit signed integers X,YX, Y and ZZ represented using the sign-magnitude form. The binary representations of XX and YY are as follows: X:10110100Y:01001100X: 10110100 \quad Y: 01001100 Which of the following operations to compute ZZ result(s) in an arithmetic overflow?
Official PYQ2026Digital LogicBoolean AlgebraMSQ · 1 mark
Consider the following Boolean expression of a function FF : F(P,Q)=(Pˉ+Q)⊕(PˉQ)F(P, Q)=(\bar{P}+Q) \oplus(\bar{P} Q) Which of the following expressions is/are equivalent to FF ?
Official PYQ2026Digital LogicNumber Representations (Fixed and Floating Point)MCQ · 2 marks
Consider the real valued variables X,YX, Y and ZZ represented using the IEEE 754754 singleprecision floating-point format. The binary representations of XX and YY in hexadecimal notation are as follows: X:35C00000Y:34A00000X: 35 \mathrm{C} 00000 \quad Y: 34 \mathrm{A} 00000 Let Z=X+YZ=X+Y. Which one of the following is the binary representation of ZZ, in …
Official PYQ2026Digital LogicSequential CircuitsMCQ · 2 marks
Consider a 22-bit saturating up/down counter that performs the saturating up count when the input PP is 00, and the saturating down count when PP is 11. The Next State table of the counter is as shown. The counter is built as a synchronous sequential circuit using D flip-flops. InputCureent StateNext State …
Official PYQ2026Digital LogicMinimization (K-Maps etc.)MSQ · 2 marks
Consider a Boolean function FF with the following minterm expression: F(P,Q,R,S)=∑m(1,2,3,4,5,7,10,12,13,14)F(P, Q, R, S)=\sum m(1,2,3,4,5,7,10,12,13,14) Which of the following options is/are the minimal sum-of-products expression(s) of FF ?
Official PYQ2026Digital LogicBoolean AlgebraMCQ · 1 mark
Which one of the following options is not a property of Boolean Algebra? Note: +{+} is OR operation, ⋅\cdot is AND operation, and ′{\prime} is NOT operation
Official PYQ2026Digital LogicNumber Representations (Fixed and Floating Point)MSQ · 1 mark
In a system, numbers are represented using 44-bit two's complement form. Consider four numbers N1=1011,N2=1101,N3=1010N 1=1011, N 2=1101, N 3=1010 and N4=1001N 4=1001 in the system. Which of the following operations will result in arithmetic overflow?
Official PYQ2026Digital LogicNumber Representations (Fixed and Floating Point)NAT · 1 mark
The 3232-bit IEEE\text{IEEE} 754754 single precision representation of a number is 0xC27100000\text{xC}2710000. The number in decimal representation is ____\_\_\_\_. (rounded off to two decimal places)
Official PYQ2026Digital LogicMinimization (K-Maps etc.)MCQ · 2 marks
Consider the following 44-variable Boolean function F(A,B,C,D)=Σm(0,1,2,3,8,9,10,11)F(A, B, C, D)=\Sigma m(0,1,2,3,8,9,10,11) Consider AA as MSB, DD as LSB. Which one of the following options represents the minimal sum of products form for the above function? Note: +{+} is OR operation, ⋅{\cdot} is AND operation, ′{\prime} is NOT operation
Official PYQ2026Digital LogicCombinational CircuitsNAT · 2 marks
Consider the digital circuit shown below with two input lines A\text{A} and B\text{B}, two select lines S0\text{S0} and S1\text{S1}, and an output line Y\text{Y}. The blocks Q\text{Q} and M\text{M} represent active high 2:42:4 decoder and 44-to-11 multiplexer, respectively. Out of 1616 possible input combinations, the number of …
Official PYQ2025Digital LogicBoolean AlgebraMSQ · 1 mark
Let XX be a 33-variable Boolean function that produces output as ′1′'1' when at least two of the input variables are ′1′'1'. Which of the following statement(s) is/are CORRECT, where a,b,c,d,ea, b, c, d, e are Boolean variables?
Official PYQ2025Digital LogicNumber Representations (Fixed and Floating Point)MSQ · 1 mark
The number −6-6 can be represented as 10101010 in 44-bit 22's complement representation. Which of the following is/are CORRECT 22 's complement representation(s) of −6-6?
Official PYQ2025Digital LogicMinimization (K-Maps etc.)MCQ · 2 marks
Consider the following four variable Boolean function in sum-of-product form F(b3,b2,b1,b0)=∑(0,2,4,8,10,11,12)F\left(b_{3}, b_{2}, b_{1}, b_{0}\right)=\sum(0,2,4,8,10,11,12) where the value of the function is computed by considering b3b2b1b0b_{3} b_{2} b_{1} b_{0} as a 44-bit binary number, where b3b_{3} denotes the most significant bit and b0b_{0} denotes the least significant bit. …
Official PYQ2025Digital LogicSequential CircuitsNAT · 2 marks
Consider the given sequential circuit designed using D-Flip-flops. The circuit is initialized with some value (initial state). The number of distinct states the circuit will go through before returning back to the initial state is ___________. (Answer in integer)
Official PYQ2025Digital LogicCombinational CircuitsMSQ · 1 mark
​Consider the following logic circuit diagram. Which is/are the CORRECT option(s) for the output function FF ?
Official PYQ2025Digital LogicComputer ArithmeticNAT · 1 mark
The following two signed 22 's complement numbers (multiplicand M and multiplier Q) are being multiplied using Booth's algorithm: M: 11001101111011011100110111101101 and Q: 10100100101010101010010010101010 The total number of addition and subtraction operations to be performed is_____________. (Answer in integer)
Official PYQ2025Digital LogicSequential CircuitsNAT · 1 mark
In a 44-bit ripple counter, if the period of the waveform at the last flip-flop is 6464 microseconds, then the frequency of the ripple counter in kHz is _________. (Answer in integer)
Official PYQ2025Digital LogicMinimization (K-Maps etc.)MSQ · 2 marks
​​​​Given the following Karnaugh Map for a Boolean function F(w,x,y,z)F(w, x, y, z) : Which one or more of the following Boolean expression(s) represent(s) FF ?
Official PYQ2025Digital LogicNumber Representations (Fixed and Floating Point)MSQ · 2 marks
Three floating point numbers X,YX, Y, and ZZ are stored in three registers RX,RY\mathrm{R}_{\mathrm{X}}, \mathrm{R}_{\mathrm{Y}}, and RZ\mathrm{R}_{\mathrm{Z}}, respectively in IEEEIEEE 754754 single precision format as given below in hexadecimal: …
Official PYQ2025Digital LogicBoolean AlgebraMSQ · 2 marks
Which of the following Boolean algebraic equation(s) is/are CORRECT?