So, if the input bit of D0 is high then the output is high and if the input of D0 is low then AND gate generates its output as 0. Thus, with control signal level 00 only A1 is enabled and all others get disable hence output achieved is the reflection of data bit associated with A1. So, input bit D1 decides the output of A2. If D1 is high, the output will be 1 otherwise 0. Case 3: Now consider that level of control signal a is high and that of b is low. So, applied input bit D2 will provide the desired bit at the output.
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What are the uses of a multiplexer? The applications of a multiplexer include In a communication system where we have a communication network, a multiplexer increases the efficiency of the system by allowing the transmission of audio and video data on a single channel. In optical fiber communication , a multiplexer does the same job to combine multiple fiber cables onto one fiber cable using a technique called Dense wavelength division multiplexing.
It also works as a parallel to serial data converter. In a computer, it decreases the number of copper lines necessary to connect the memory to other parts of the computer. How to join multiplexers? If we have small multiplexers, but we wish to increase their functionality, we can join them to obtain a mux with more inputs. The cascading of multiplexers is easy. You just need to make sure that you connect in a way that gives the same number of inputs and control lines as your target mux.
We know that a mux has two inputs and one select line. So joining two multiplexers will give us four inputs, two outputs we need only 1 , and two select lines. So how do we proceed? If we can somehow reduce the outputs to one, it would be really easy.
Since we wish to use only multiplexers, how do we combine two lines to get a single line? We use another mux! However, though that gives us the one output that we require, it gives us an additional select line. So now we have three select lines. How do you reduce three select lines to two select lines? If only we could just remove one select line.
Well, we can do that by joining two select lines. That would essentially reduce the two lines to one single line. This is the result we get by applying our logic. Similar to the process we saw above, you can design an 8 to 1 multiplexer using multiplexers, mux using mux, or mux using multiplexer.
Try designing these using only multiplexers using similar logic to the one we saw above. Cross-check your answers with the designs below. Joining multiplexers You can also go the opposite way and use a multiplexer with more inputs than required as a smaller mux. Larger mux to smaller mux How to make logic gates using multiplexers? Since the logic gates we study are generally with two inputs and have one output, we can take it up as a logical challenge to design all logic gates using a multiplexer.
As with a lot of logical circuits, making gates using mux also does not have a method written in stone. You can try alternative designs and arrive at the same logical conclusions. We know that it just inverts the input and has one input. NOT gate using Mux Similarly, by applying some logic, you can derive all other gates using just Mux.
Try it! Logic gates using Multiplexer What is a demultiplexer? A demultiplexer is a combinational logic circuit that performs the opposite function as that of a multiplexer. In a demux, we have n output lines, one input line, and m select lines.
The relation between the number of output lines and the number of select lines is the same as we saw in a multiplexer. Depending on the value of the binary number formed by the select lines, any one of the output lines connects to the input line.
The rest of the output lines at this point go to an OFF state. That is, the value of the remaining lines is 0. In this way, a demultiplexer converts serial data to parallel data and acts as a serial-parallel converter. The general symbol of a demultiplexer is shown below. To understand the working of a demultiplexer, we will straight away design one.
The demux is the simplest of all demultiplexers.
Operations of Multiplexer and De-multiplexer Circuit and Applications
All About Electronics Demultiplexer Definition: Demultiplexer performs the reverse operation of the multiplexer i. The output to which the input signal is to be passed is decided by the control logic. The control logic can be manipulated by changing the value of the control signal. Thus, it is termed as the demultiplexer as it takes one input and generates several outputs. There can be various types of demultiplexer circuits depending on the number of output. The input will be always one in number. The demultiplexer can be digital as well as analogue depending on the type of input and output.
Difference Between Multiplexer (MUX) and Demultiplexer (DEMUX)
Schematic Demultiplexer A demultiplexer or demux is a device that takes a single input line and routes it to one of several digital output lines. A demultiplexer of 2n outputs has n select lines, which are used to select which output line to send the input. A demultiplexer is also called a data distributor. Demultiplexers can be used to implement general purpose logic. By setting the input to true, the demux behaves as a decoder. The reverse of the digital demultiplexer is the digital multiplexer 1 to 4 demultiplexer A 1 to 4 multiplexer uses 2 select lines S0, S1 to determine which one of the 4 outputs Y0 - Y3 is routed from the input D.
Multiplexer and Demultiplexer – The ultimate guide
What are the uses of a multiplexer? The applications of a multiplexer include In a communication system where we have a communication network, a multiplexer increases the efficiency of the system by allowing the transmission of audio and video data on a single channel. In optical fiber communication , a multiplexer does the same job to combine multiple fiber cables onto one fiber cable using a technique called Dense wavelength division multiplexing. It also works as a parallel to serial data converter. In a computer, it decreases the number of copper lines necessary to connect the memory to other parts of the computer.
Multiplexer and Demultiplexer
Want create site? Find Free WordPress Themes and plugins. Multiplexer and demultiplexer are two devices very important in data communications. As the name implies, their functions are opposite to each other similar to encoder and decoder. These devices are used for sharing a device between two or more applications.