Multiplexer
The multiplexer is a device that has multiple inputs and a single-line output. The select lines determine which input is connected to the output, and also increase the amount of data that can be sent over a network within a certain time. It is also called a data selector.
The single pole multi-position switch is a simple example of a non-electronic circuit of the multiplexer. Multiplexers are capable of handling both analog and digital applications.
In analog applications, multiplexers are made up of relays and transistor switches, whereas in digital applications, the multiplexers are built from standard logic gates. When the multiplexer is used for digital applications, it is called a digitalmultiplexer.
Multiplexer Types
Multiplexers are classified into four types:
- 2-1 multiplexer (I select line)
- 4-1 multiplexer (2 select lines)
- .8-1 multiplexer (3 select lines)
- 16-1 multiplexer (4 select lines)
Multiplexer Applications
A Multiplexer is used in various applications wherein multiple data can be transmitted to using a single line.
1. Communication System
A Multiplexer is used in communication systems, which have a transmission system and also a communication network. A Multiplexer has increased the efficiency of the communication system allowing the transmission of data, such as audio and video data from different channels via cables and single lines
2. Computer Memory
A Multiplexer is used in computer memory to keep up a vast amount of memory in the computers, and also to decrease the number of copper lines necessary to connect the memory to other parts of the computer
3. Telephone Network
A multiplexer is used in telephone networks to integrate multiple audio signals on a single line of transmission.
4. Transmission from the Computer System of a Satellite
A Multiplexer is used to transmit the data signals from the computer system of a satellite to the ground system by using a GSM communication.
Multiplexer Truth Table
A truth table is a tabular representation of all possible input combinations and the corresponding output for a logic circuit.
A truth table for a 2-to-1 multiplexer would have three inputs (I0, I1, and S) and one output (Y). It would look like this:
S | I0 | I1 | Y |
---|---|---|---|
0 | 0 | 0 | 0 |
0 | 0 | 1 | 0 |
0 | 1 | 0 | 1 |
0 | 1 | 1 | 1 |
1 | 0 | 0 | 0 |
1 | 0 | 1 | 1 |
1 | 1 | 0 | 0 |
1 | 1 | 1 | 1 |
In this example, when S is 0, I0 is connected to the output Y, and when S is 1, I1 is connected to the output Y.
A truth table for a 4-to-1 multiplexer would have five inputs (I0, I1, I2, I3, and S1,S2) and one output (Y). It would have 16 rows and 6 columns representing all possible combinations of inputs and the corresponding output.