The Gateway to Computer Science Excellence
First time here? Checkout the FAQ!
+18 votes

Consider the following combinational function block involving four Boolean variables $x,\:y,\:a,\:b$ where $x,\:a,\:b$ are inputs and $y$ is the output.

f(x, a, b, y)
    if(x is 1) y = a;
    else y = b;

Which one of the following digital logic blocks is the most suitable for implementing this function?

  1. Full adder
  2. Priority encoder
  3. Multiplexor
  4. Flip-flop
asked in Digital Logic by Veteran (115k points)
retagged by | 1.5k views

3 Answers

+23 votes
Best answer

$\text{If} \qquad X=1 \qquad Y=a;$
$\text{else}\quad (X=0)\qquad Y = b;$

$\text{Input}: (a,b,X)\qquad\qquad \text{Output}: Y$

$Y = \bar X b + Xa.$

answered by Loyal (8.5k points)
edited by
Why can't it be flip flop? Please explain
Flip is one bit storage device. It will store one bit.We dont have any selection logic in flip flop as in MUX


Can we implement it using priority encoder ???

2 X 1 Priority encoder

Input (No use)        X  Output (Y)
$\phi$       1  a
$\phi$       0     b 


Same doubt.
+16 votes
2X1 multiplexer
answered by Active (3.6k points)
+3 votes
lovely question x1=a x0=b MULTIPLEXER
answered by Active (3.4k points)

Related questions

Quick search syntax
tags tag:apple
author user:martin
title title:apple
content content:apple
exclude -tag:apple
force match +apple
views views:100
score score:10
answers answers:2
is accepted isaccepted:true
is closed isclosed:true
47,910 questions
52,287 answers
67,727 users