A digital multiplexer is a combined logic device designed to control the transmission of information from multiple sources through a single output channel.
Digital multiplexer architecture
The architecture of a digital multiplexer is a device equipped with multiple digital position switches. The purpose of their work is to switch input signals to ensure their transmission to a single output line.
A digital multiplexer typically has three groups of input channels. Addressable, the binary code of which is used to determine the connection between the information input and the final output, informational and permissive, they are also called strobing.
In modern integrated circuits, the digital multiplexer is equipped with a maximum of sixteen information inputs.
If during the design it turns out that more information inputs are required, then the problem is solved by creating the structure of the so-called multiplexer tree, which is equipped with several integrated circuits.
The digital multiplexer is designed to synthesize virtually any logic device required, thereby reducing the total number of logic elements used.
To determine the need, the following actions are performed: based on the output function, according to the values of the variables, a Karnot map is built. Next, the order of operation of the multiplexer in the circuit is determined. Then, a masking matrix is constructed without fail corresponding to the order of the applied multiplexer.
After that, the resulting matrix is superimposed on the Karnot map. Then the function is minimized for each of the regions of the available matrix. At the end, based on the obtained results of minimization, a scheme is built. These are the rules for synthesis based on the use of a multiplexer.
Multiplexer capabilities
The use of multiplexers is multifaceted. For example, flexible multiplexers can form continuous primary digital streams at a rate of 2048 kbit / s based on analog signals. Also switch data of digital interfaces by cross-switching electronic channels at speeds up to 64 kbit / s.
In addition, they carry out the transmission of a digital stream over the IP / Ethernet network, and also provide the conversion of line signaling and physical joints.
Flexible multiplexers, in addition, provide the ability to implement broadcast connections, that is, the supply of signals from one of the digital or analog sources to several others at once. For this reason, they are often used to transmit broadcast programs simultaneously to several different locations.
