1. It is a combinational circuit.
The basic design unit of MUX is :
It means in a MUX, there are
- input lines
- select lines // Select lines are used to select the inputs.
- 1 output
2. A multiplexor is a functionally complete combinational circuit. for example, a 4*1 MUX can represent any Boolean function of two variable.
3. To implement an n variable boolean function you need MUX, in normal case.
Implementing 4*1 MUX
Sometimes you need to implement an n variable boolean function, but you need some additional circuit to implement this.