Multiplexer

Schematic of a 2-to-1 multiplexer. It can be equated to a controlled switch.
Schematic of a 1-to-2 demultiplexer. Like a multiplexer, it can be equated to a controlled switch.

In electronics, a multiplexer (or mux; spelled sometimes as multiplexor), also known as a data selector, is a device that selects between several analog or digital input signals and forwards the selected input to a single output line.[1] The selection is directed by a separate set of digital inputs known as select lines. A multiplexer of inputs has select lines, which are used to select which input line to send to the output.[2]

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 demultiplexer (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.[1]

An electronic multiplexer can be considered as a multiple-input, single-output switch, and a demultiplexer as a single-input, multiple-output switch.[3] The schematic symbol for a multiplexer is an isosceles trapezoid with the longer parallel side containing the input pins and the short parallel side containing the output pin.[4] The schematic on the right shows a 2-to-1 multiplexer on the left and an equivalent switch on the right. The wire connects the desired input to the output.

  1. ^ a b Dean, Tamara (2010). Network+ Guide to Networks. Delmar. pp. 82–85. ISBN 978-1423902454.
  2. ^ Debashis, De (2010). Basic Electronics. Dorling Kindersley. p. 557. ISBN 9788131710685.
  3. ^ Lipták, Béla (2002). Instrument engineers' handbook: Process software and digital networks. CRC Press. p. 343. ISBN 9781439863442.
  4. ^ Harris, David (2007). Digital Design and Computer Architecture. Penrose. p. 79. ISBN 9780080547060.