A demultiplexer has N control inputs that determine which of its 2N outputs receives the single data input. It performs the opposite function of a multiplexer by routing the data input to the selected output based on the control input values. Demultiplexers are used to distribute a data signal to multiple outputs based on a select code.

1. LOGIC DESIGN
Demultiplexers

2. 
A demultiplexer has
N control inputs
1 data input
2N outputs

A demultiplexer routes (or connects) the data
input to the selected output.
The value of the control inputs determines the
output that is selected.

A demultiplexer performs the opposite function of
a multiplexer.

3. Out0
I
Out1
In
Out2
Out3
S1 S0
A B
W
X
Y
Z
W = A'.B'.I
X = A.B'.I
Y = A'.B.I
Z = A.B.I