Encoders and decoders are similar to multiplexers and demultiplexers, except that they are a little bit more complicated.

Decoders

Decoders will have N inputs, and ${\displaystyle 2^{N}}$ output. Let's say that we have two inputs (A and B), and 4 outputs (M N O P). Decoders will satisfy the following truth table:

Binary numbers come in, and essentially select which wire to send a signal on. chankana

Encoders

Encoders work in exactly the opposite way as decoders, taking ${\displaystyle 2^{N}}$ inputs, and having N outputs. When a bit comes in on an input wire, the encoder outputs the physical address of that wire.It takes 2^n inputs and gives out n outputs,the enable pin should be kept 1 for enabling the circuit.

Priority Encoders

A Priority Encoder works opposite of the decoder circuit. Priority Encoders have logical ranking within them, input₁ may be higher than input₂. If input₂ and input₁ were pressed, the encoder would determine the priority, and accept the input.

Encoders and Multiplexers

The relationship between the two.

A multiplexer (MUX) is a combination circuit that contains more than one input line, one output line and more than one selection line. Whereas, an encoder is also considered a type of multiplexer but without a single output line.It is a combinational logic function that has 2^n (or fewer) input lines and n output lines.

This section of the Digital Circuits wikibook is a stub. You can help by expanding this section. If you add something, list yourself as a Contributor.