Questions
Syllabus
Qns. By Syllabus

Semester

Subject

Year

Tribhuwan University

Institute of Science and Technology

2079

Bachelor Level / First Year / First Semester / Science

B.Sc in Computer Science and Information Technology (CSC116)

(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 the sequential circuit with respect to the following state diagram using T flip flops. [10]
2.
Implement F=Σ(1,4,5,7)F = \Sigma(1,4,5,7) using a. Multiplexer b. Decoder c. PLA [10]
3.
Differentiate between combinational circuit and sequential circuit. Design mod-10 synchronous counter using J-K flip-flop. Show necessary truth tables and K-maps. [10]
Section B

Short Answers Questions

Attempt any Eight questions.
[8*5=40]
4.
Provide one example where shift left operator can be used. Explain serial-in-serial-out register. [5]
5.
Carry out the following tasks:a. Perform 2's complement subtraction of 010110 - 100101b. Represent decimal number 10 in its BCD form [5]
6.
Derive the Boolean expression for sum and carry of half adder. Draw its combinational circuit. Implement it using only NOR gates. [5]
7.
Express F′=(x+y+z)′F' = (x + y + z)' as a sum of min-terms. [5]
8.
Minimize the following Boolean function using K-map F(A,B,C,D)=Σm(0,1,2,5,7,8,9,10,13,15)F(A, B, C, D) = \Sigma m(0,1,2,5,7,8,9,10,13,15). [5]
9.
What are the practical implications of down counter? Explain BCD ripple counter. [5]
10.
Design a combinational circuit with three inputs and one output. The output is 1 when the binary value of the inputs is an even number. [5]
11.
Differentiate between ROM and PLA. Explain different types of ROM. [5]
12.
Write short notes on (Any two): a. Positive Logic b. I2L c. ASCII [5]