Tribhuwan University

Institute of Science and Technology

2077

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.
What is decoder? Design BCD to Decimal Decoder with truth table and logic diagram.[10]
2.
Design a combinational circuit whose input is a four-bit number and output is 2's complement of the input number.[10]
3.
What is ring counter? Explain ring counter with diagram, timing sequence and timing diagram.[10]
Section B

Short Answers Questions

Attempt any Eight questions.
[8*5=40]
4.
Convert (1011.110) into decimal and hexadecimal. [5]
5.
Substract (1011.11- 1010.10) using 2's and l's complement. [5]
6.
Express the given function in sum of minterms. F = y'z + wxy' + wzx' + w'x'z' [5]
7.
Simplify the Boolean function using don't care conditions d in sum of products form. and product of sums form $F(A, B, C, D) = \pi(1, 3, 7, 8, 12) \text{ and } \pi d(5, 10, 13, 14)$ [5]
8.
Implement a full subtractor with two half subtractors and one OR Gate. [5]
9.
Define SR latch with logic diagram and truth table. [5]
10.
Compare the logic of synchronous counter and ripple counter. [5]
11.
Define shift register with its types. [5]
12.
Write short notes on: a.) Parity generator Write short notes on: a.) State Diagram [2.5+2.5]