Electronic – Analog Multiplexer


I am almost completely new to electronics. Recently I was reading about an 'analog multiplexer' I know what a multiplexer does, and how it works, but is there such a thing as a 'digital multiplexer' that would just give +5v when a channel was on?

Pardon if my question is malformed, I just started in on electronics two days ago.

OK, so the difference is that a 'digital' multiplexer will just output +5/0, and an 'analog' multiplexer will just pass the input signal with as little distortion as possible ?

Best Answer

A big difference between analog and digital multiplexers is that the former can be used bidirectionally, while the latter are unidirectional. That means that analog multiplexers can also be used as demultiplexer, while for digital you need separate ICs for that. There are also several types, depending on the number of in/outputs:

multiplexers (non-exhaustive)
8-input: 74HC151, 74HC251,
dual 4-input: 74HC153, 74HC253,
quad 2-input: 74HC157, 74HC257.

demultiplexers (non-exhaustive)
3-to-8 inverting: 74HC138,
3-to-8 non-inverting: 74HC238,
dual 2-to-4: 74HC139.