Multiplexer and demultiplexer in dld pdf
File Name: multiplexer and demultiplexer in dld .zip
- Digital Circuits - De-Multiplexers
- Difference Between Multiplexer (MUX) and Demultiplexer (DEMUX)
Digital design using mux - demultiplexer in digital logic design book pdf free download as powerpoint presentation. Ppt , pdf file. Pdf , text file.
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.
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. An electronic multiplexer can be considered as a multiple-input, single-output switch, and a demultiplexer as a single-input, multiple-output switch. One use for multiplexers is economizing connections over a single channel, by connecting the multiplexer's single output to the demultiplexer's single input.
The image to the right demonstrates this benefit. At the receiving end of the data link a complementary demultiplexer is usually required to break the single data stream back down into the original streams. In some cases, the far end system may have functionality greater than a simple demultiplexer; and while the demultiplexing still occurs technically, it may never be implemented discretely. This would be the case when, for instance, a multiplexer serves a number of IP network users; and then feeds directly into a router , which immediately reads the content of the entire link into its routing processor; and then does the demultiplexing in memory from where it will be converted directly into IP sections.
Often, a multiplexer and demultiplexer are combined together into a single piece of equipment, which is simply referred to as a multiplexer. Both circuit elements are needed at both ends of a transmission link because most communications systems transmit in both directions. In analog circuit design, a multiplexer is a special type of analog switch that connects one signal selected from several inputs to a single output.
In digital circuit design, the selector wires are of digital value. For example, 9 to 16 inputs would require no fewer than 4 selector pins and 17 to 32 inputs would require no fewer than 5 selector pins. The binary value expressed on these selector pins determines the selected input pin.
While this is mathematically correct, a direct physical implementation would be prone to race conditions that require additional gates to suppress. Other common sizes are 4-to-1, 8-to-1, and to Since digital logic uses binary values, powers of 2 are used 4, 8, 16 to maximally control a number of inputs for the given number of selector inputs.
The following 4-to-1 multiplexer is constructed from 3-state buffers and AND gates the AND gates are acting as the decoder :.
Larger Multiplexers can be constructed by using smaller multiplexers by chaining them together. For example, an 8-to-1 multiplexer can be made with two 4-to-1 and one 2-to-1 multiplexers. The two 4-to-1 multiplexer outputs are fed into the 2-to-1 with the selector pins on the 4-to-1's put in parallel giving a total number of selector inputs to 3, which is equivalent to an 8-to The series has several ICs that contain multiplexers:.
Demultiplexers take one data input and a number of selection inputs, and they have several outputs. They forward the data input to one of the outputs depending on the values of the selection inputs. Demultiplexers are sometimes convenient for designing general-purpose logic because if the demultiplexer's input is always true, the demultiplexer acts as a binary decoder. This means that any function of the selection bits can be constructed by logically OR-ing the correct set of outputs.
The series has several ICs that contain demultiplexers:. Multiplexers can also be used as programmable logic devices , specifically to implement Boolean functions. Any Boolean function of n variables and one result can be implemented with a multiplexer with n selector inputs.
The variables are connected to the selector inputs, and the function result, 0 or 1, for each possible combination of selector inputs is connected to the corresponding data input.
This is especially useful in situations when cost is a factor, for modularity, and for ease of modification. From Wikipedia, the free encyclopedia. This article is about electronics switching. For telecommunications, see multiplexing. See also: Inverse multiplexer.
Basic Electronics. Dorling Kindersley. Instrument engineers' handbook: Process software and digital networks. CRC Press. Digital Design and Computer Architecture. Lancaster The TTL Cookbook.
Howard W. Processor technologies. Data dependency Structural Control False sharing. Tomasulo algorithm Reservation station Re-order buffer Register renaming Wide-issue. Branch prediction Memory dependence prediction. Single-core Multi-core Manycore Heterogeneous architecture. Processor register Status register Stack register Register file Memory buffer Memory address register Program counter. Categories : Multiplexing Digital circuits. Namespaces Article Talk.
Views Read Edit View history. Help Learn to edit Community portal Recent changes Upload file. Download as PDF Printable version. Wikimedia Commons. GND : MA :
Digital Circuits - De-Multiplexers
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. 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.
Difference Between Multiplexer (MUX) and Demultiplexer (DEMUX)
One of these data inputs will be connected to the output based on the values of selection lines. So, each combination will select only one data input. Multiplexer is also called as Mux. The block diagram of 4x1 Multiplexer is shown in the following figure.
To understand the operation of a multiplexer and demultiplexer.
Key Differences Multiplexer and Demultiplexer
The major factor that differentiates multiplexer and demultiplexer is their ability to accept multiple input and single input respectively. The multiplexer also known as a MUX operates on several inputs but provide a single output. As against demultiplexer also known as DEMUX simply reverses the operation of MUX and operates on single input but transmits the data to multiple outputs. It is noteworthy here that multiplexer acts as data selector thus provide a single output from several inputs. However, demultiplexer acts as a data distributor and generates several outputs with a single input. We will discuss some other major differences between MUX and DEMUX but before that have a look towards the contents to be discussed under this article.
De-Multiplexer is a combinational circuit that performs the reverse operation of Multiplexer. The input will be connected to one of these outputs based on the values of selection lines. So, each combination can select only one output. De-Multiplexer is also called as De-Mux. The block diagram of 1x4 De-Multiplexer is shown in the following figure. The Truth table of 1x4 De-Multiplexer is shown below. From the above Truth table, we can directly write the Boolean functions for each output as.