Questions
Syllabus
Qns. By Syllabus

Semester

Subject

Year

Credit:Eli TamangEli Tamang

Tribhuwan University

Institute of Science and Technology

2081

Bachelor Level / First Year / First Semester / Science

Bachelors in Information Technology (BIT103)

(Digital Logic)

Full Marks: 60

Pass Marks: 24

Time: 3 Hours

Candidates are required to give their answers in their own words as for as practicable.

The figures in the margin indicate full marks.

Section A

Long Answers Questions

Attempt any TWO questions.
[2*10=20]
1.
Design a combinational circuit with three inputs. The output is 1 when the binary value of the input is odd. [10]
2.
Define magnitude comparator? Design a 4-bit magnitude comparator circuit. [2+8]
3.
What is counter? Design a 3-bit synchronous up-down counter along with state diagram and timing sequence. [2+8]
Section B

Short Answers Questions

Attempt any Eight questions.
[8*5=40]
4.
Convert (257)₈ into hexadecimal and decimal number system. [5]
5.
Perform following arithmetic operation:
a)101101+011011a) 101101 + 011011
b)101111−010101b) 101111 - 010101
[5]
6.
Simplify (using K-map):
F=(A+B+C+D′)(A+B+C′+D)(A+B′+C′+D′)(A+B′+C′+D)(A′+B′+C′+D)(A′+B+C+D′)(A′+B+C′+D)F = (A + B + C + D')(A + B + C' + D)(A + B' + C' + D')(A + B' + C' + D)(A' + B' + C' + D)(A' + B + C + D')(A' + B + C' + D)
[5]
7.
Define multiplexer. Implement 8 × 1 multiplexer using 2 × 1 multiplexer. [1+4]
8.
What is Flip Flop? Differentiate between Combinational circuit and Sequential Circuit. [2+3]
9.
Realize JK flip-flop from RS flip-flop. [5]
10.
Define shift register. Explain the operation of 4-bit Serial-In Serial-Out Shift register with data input 1011. [1+4]
11.
Define shifter. Design a 4-bit shifter circuit. [1+4]
12.
Write short notes on: a) De-Multiplexer b) Excitation table [0+2.5+2.5]