No. of Printed Pages: 3 IBIEE..()17I
.B.Tech. -VIEP -ELECTRICAL ENGINEERING
(BTELVI)
Term-End Examination

0034..5 December, 2016
BIEE-017 DIGITAL ELECTRONICS
Time hours Maximum Marks: 70
Note: Attempt any five questions. All questions. carry equal marks. Missing data may be suitably assumed. Use of scientific calculator is permitted.

1. Find the complement of F wx yz and then show that F. F 0 an F F 1. 7

Given two eight-bit strings, 10110001 and B 10101100, evaluate the following: 7

NOT A

NOT B

AND

OR

XOR

2. Prove that the dual of the EX-OR is also its complement. 7

Implement the following four Boolean expressions with three half adders:



E=ABC+ABC

F=ABC B)C

G=ABC

3. Define the term combinational circuit and give its simple block diagram representation. Design a combinational circuit for BCD to excess-3 code converter. 14

4. Explain the operation of a 4-bit adder/subtractor circuit with the help of a clearly labelled logic diagram and a simple mathematical example. How do the circuit defects overflow, if any exist? 14

5. What is a Read Only Memory Give a simple block diagram of a ROM. Clearly explain the working principle of a ROM with the help of an internal logic diagram of a 32 x 8 ROM. 14

6. Give the architectural structure of the following:

8085 microprocessor

8086 microprocessor

What are the basic differences between the two 14

7. Write short notes on any two of the following: 2 x 7=14

Addressing Modes of 8085

Instruction Format of 8086

Comparison of 8088 with 8086 .