UNIVERSITY OF NAMIBIA – School of Engineering and the Built Environment
Department of Electronics and Computer Engineering
DIGITAL ELECTRONICS - TUTORIAL
Question 1
(i)
Add the following decimal numbers in BCD: 6510 + 5810
(3)
(ii)
Add DDCC16 + BBAA16 and express your answer in dec and oct
(3)
(iii)
Add 7238+2378 and express your answer in hex
(3)
Question 2
Using your knowledge of Boolean algebra, simplify the following expression
(𝐶 + 𝐶𝐷)(𝐶 + 𝐶̅ 𝐷)(𝐶 + 𝐸)
(3)
Question 3
3.1
Use a Karnaugh map to find a minimum POS for the expression:
̅+𝑫
̅ + 𝑫)
̅+𝑩
̅ + 𝑪 + 𝑫)(𝑨 + 𝑩
̅ + 𝑪 + 𝑫)(𝑨 + 𝑩 + 𝑪 + 𝑫
̅ )(𝑨 + 𝑩 + 𝑪
̅ )(𝑨
̅+𝑩+𝑪+𝑫
̅ )(𝑨 + 𝑩 + 𝑪
(𝑨
(6)
3.2
(4)
Find the equivalent minimum SOP for the expression in 3.1
Question 4
Simplify the following expressions using Karnaugh map
4.1
̅ + 𝐶𝐷
̅ + 𝐴𝐶̅ + 𝐴̅𝐵̅
𝑓(𝐴, 𝐵, 𝐶, 𝐷) = 𝐴̅𝐵̅𝐶 + 𝐴𝐷 + 𝐵𝐷
(8)
4.2
𝑓(𝐴, 𝐵, 𝐶, 𝐷) = 𝜋(1, 2, 4, 5, 7, 8, 10, 11, 13, 14)
(6)
Q5:
Design a logic circuit that can add 5 to any 3 bit number presented on its
input. Your answer should consist of a truth table, and the logic circuit. NB:
Use the K-maps for simplification of your logic expressions.
[15]