Home
LogicRoo / Combinational Gates / Multiplexer - Truth Table, Boolean Expression & Logic Circuit | Logicroo
Digital Multiplexer

Multiplexer - Truth Table, Boolean Expression & Logic Circuit | Logicroo

Learn about Digital Multiplexers with interactive circuit diagrams, truth tables, Boolean expressions, selection logic, logic gate implementation, and digital logic examples.

4-to-1 Multiplexer

Digital Multiplexer

A multiplexer selects one of several data inputs and routes it to a single output, based on the value of its select lines. With two select inputs S1S0, the 4:1 MUX steers one of four data lines I0–I3 through to Y — Y = I0·S1'S0' + I1·S1'S0 + I2·S1S0' + I3·S1S0. Each term needs an inverted select (NOT), a select-minterm AND, a data AND, and a final OR to merge them — a four gate delay circuit.

Select inputs
Data inputs
Y
1
Selected line
I0
Delay
Y = I0·S1'S0' + I1·S1'S0 + I2·S1S0' + I3·S1S0 (4 gate delay — NOT, AND, AND, OR)
Exactly one data line drives Y for every select combination; the other three are gated off.
Truth table (select sweep, current data values)
S1S0SelectedY