{"id":7957,"date":"2022-05-25T17:36:38","date_gmt":"2022-05-25T12:06:38","guid":{"rendered":"https:\/\/www.goseeko.com\/blog\/?p=7957"},"modified":"2026-04-23T05:26:03","modified_gmt":"2026-04-22T23:56:03","slug":"what-is-encoder","status":"publish","type":"post","link":"https:\/\/www.goseeko.com\/blog\/what-is-encoder\/","title":{"rendered":"What is Encoder?\ufffc"},"content":{"rendered":"\n

The reverse operation of the Decoder<\/a> is performed by an encoder, which is a combinational circuit. There are a total of 2n input lines and ‘n’ output lines. It will generate a binary code that is equivalent to the active High input. As a result, the encoder uses ‘n’ bits to encode 2n input lines. In encoders, representing the enable signal is optional.<\/p>\n\n\n\n

4 to 2 line Encoder:<\/strong><\/h2>\n\n\n\n

There are four inputs (Y0, Y1, Y2, and Y3) and two outputs (A0 and A1) in the 4 to 2 line encoder. In addition, To get the respective binary code on the output side, one input line at a time is set to true in a 4-input line. The 4 to 2 line encoder’s block diagram and truth table are shown below.<\/p>\n\n\n\n

<\/p>\n\n\n\n

Truth table<\/p>\n\n\n

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\"\"<\/figure><\/div>\n\n\n

The terms A0 and A1 are logically expressed as follows:<\/p>\n\n\n\n

A1<\/sub>=Y3<\/sub>+Y2<\/sub><\/p>\n\n\n\n

A0<\/sub>=Y3<\/sub>+Y1<\/sub><\/p>\n\n\n\n

Circuit Diagram<\/strong><\/p>\n\n\n\n

Two input OR gates can be used to implement the aforementioned two Boolean functions. Further, The 4 to 2 encoder circuit diagram is given in the graphic below.<\/p>\n\n\n\n

<\/p>\n\n\n\n

Octal to Binary Encoder<\/strong><\/h2>\n\n\n\n

The octal to binary encoder has eight inputs, ranging from Y7 to Y0, and three outputs, A2, A1, and A0. The 8 to 3 encoder is the same as the octal to binary encoder. The following graphic depicts the block diagram of an octal to binary encoder.<\/p>\n\n\n\n

Only one of these eight inputs can be ‘1’ at any given time in order to obtain the binary code. The octal to binary encoder’s truth table is presented below.<\/p>\n\n\n\n

Truth Table<\/strong><\/p>\n\n\n\n

\"Encoder<\/figure>\n\n\n\n

The following is the logical expression of the terms A0, A1, and A2:<\/p>\n\n\n\n

A2<\/sub>=Y4<\/sub>+Y5<\/sub>+Y6<\/sub>+Y7<\/sub><\/p>\n\n\n\n

A1<\/sub>=Y2<\/sub>+Y3<\/sub>+Y6<\/sub>+Y7<\/sub><\/p>\n\n\n\n

A0<\/sub>=Y7<\/sub>+Y5<\/sub>+Y3<\/sub>+Y1<\/sub><\/p>\n\n\n\n

Circuit Diagram<\/strong><\/p>\n\n\n\n

The following is the logical circuit for the above expressions:<\/p>\n\n\n\n

<\/p>\n\n\n\n

Uses of Encoder<\/strong><\/h2>\n\n\n\n

In all digital systems, these systems are relatively simple to operate.<\/p>\n\n\n\n

To convert a decimal number to a binary number, encoders are employed. The goal is to complete a binary operation like addition, subtraction, multiplication, and so on.<\/p>\n\n\n\n

Disadvantages <\/strong><\/h2>\n\n\n\n

The disadvantages of a standard encoder are listed below.<\/p>\n\n\n\n