Multiplexer and Demultiplexer
Multiplexing and demultiplexing are the two processes which are implemented on multiplexer and demultiplexer. This significantly reduces IC package count and there by reducing the system cost.
- Logic circuit capable of accepting more than one input simultaneously and chooses one(more) input signal as output signal and is controlled by set of select inputs.
- Constrained relation: 2m = n
where m = a set of select inputs.
n = set of input signals which is even.
Y = output signal.
- Enables multiple analog signals or digital data streams to be transferred along the same channel over a shared medium.
- Increases the capacity of low level channels into high level channels.
- Minimizes IC package count and logic design is simplified.
- Example 4 : 1 multiplexer
- Logic circuit that performs the reverse operation of multiplexer.
- It accepts one input and circulates it over many outputs.
- Select lines decides to which output the data input will be transmitted.
- If it has 2n output lines, then it has n input lines.
- Requires additional gates to realize Boolean expressions.
- Used as binary-to-decimal decoder with binary inputs applied at select input lines.
- Example 1 : 4 demultiplexer
Multiplexer and Demultiplexer had played a major role in all types of communications by saving the cost of instruments.