Logic Diagram Encoder

In many circuits this problem is solved by adding sequential logic in order to know not just what input is active but also which order the inputs became active.

Logic diagram encoder. We can implement the above boolean functions using logic gates. It is convenient to use an and gate as the basic decoding element for the output because it produces a high or logic 1 output only when all of its inputs are logic 1. The decoders and encoders are designed with logic gate such as an or gate. The inputs are represented by x y and z while the compliments are.

Here a 4 bit encoder is being explained along with the truth table. Encoders an encoder is a combinational circuit that converts binary information in the form of a 2 n input. Encoder in digital logic an encoder is a combinational circuit that performs the reverse operation of decoder it has maximum of 2 n input lines and n output lines hence it encodes the information from 2 n inputs into an n bit code. The above circuit diagram contains two 2 input or gates one 4 input or gate one 2input and gate an inverter.

Encoders convert 2 n lines of input into a code of n bits and decoders decode the n bits into 2 n lines. There are different types of encoders and decoders like 4 8 and 16 encoders and the truth table of encoder depends upon a particular encoder chosen by the user. Prerequisite encoder decoders binary code of n digits can be used to store 2 n distinct elements of coded information. The circuit diagram of 4 to 2 priority encoder is shown in the following figure.

3 to 8 line decoder has a memory of 8 stages.