Demultiplexer (DEMUX)

1-to-4 DEMUX — route a single input to one of 4 outputs using 2 selector bits.

Data Input & Selector
Input
|
S0
S1
Input = 1, Selector = 01 = 1 → route to Y1 = 1
Outputs
Y00
Y11
Y20
Y30
Block Diagram
DEMUX1-to-4D=1Y0=0Y1=1Y2=0Y3=0S0=0S1=1
Selection Table
InputS0S1Y0Y1Y2Y3
1001000
1010100
1100010
1110001
About the Demultiplexer
A 1-to-4 demultiplexer is the reverse of a MUX: it takes a single data input and routes it to one of 4 output lines selected by the 2-bit selector. All other outputs remain 0. A DEMUX with the input tied to 1 behaves identically to a decoder. DEMUXes are used in data distribution, serial-to-parallel conversion, and memory write-enable decoding.