Multiplexers and Demultiplexers
295
Problems
1. Implement the three-variable Boolean function FFAA BB CC = AAC + AABBC + AABBC using (i) an
8-to-1 multiplexer and (ii) a 4-to-1 multiplexer.
(i) Fig. 8.27(a); (ii) Fig. 8.27(b)
8-to-1
MUX
F
I 0
I 1
I 2
I 3
I 4
I 5
I 6
I 7
S 2 S 1 S 0
A B C
(a)
4-to-1
MUX
I 0
I 1
I 2
I 3 S 1 S 0
B
C
(b)
A
F
'0’ '1’
'0’
'1’
Figure 8.27 Problem 1.
2. Design a 32-to-1 multiplexer using 8-to-1 multiplexers having an active LOW ENABLE input and
a 2-to-4 decoder.
Fig. 8.28