Multiplexer and De-multiplexer

Abstract

Multiplexer (or Mux) is a device that selects between several digital (or analog) input signals and forwards the selected input to a single output line. The selection is directed by a separate set of digital inputs known as select lines. A multiplexer makes it possible for several input signals to share one device or resource, for example, one analog-to-digital converter or one communications transmission medium, instead of having one device per input signal. Multiplexers can also be used to implement Boolean functions of multiple variables. Conversely, a de-multiplexer (or Demux) is a device taking a single input and selecting signals of the output of the compatible mux, which is connected to the single input, and a shared selection line. A multiplexer is often used with a complementary demultiplexer on the receiving end. This chapter studies the multiplexer and demultiplexers.