Encoders and decoders are digital electronic devices used in digital systems for encoding and decoding data, respectively. They are essential components in various applications, including data compression, error detection and correction, address decoding, and multiplexing/demultiplexing.
- Encoders:
An encoder is a device that takes multiple input lines and produces a coded output based on the input values. It converts a set of input signals into a binary code representation.
a. Priority Encoder:
A priority encoder is a type of encoder that assigns priority to the input lines. It detects the highest-priority active input and produces a binary code representing the position of that input. This is useful when multiple inputs are active simultaneously, and the encoder needs to prioritize one of them.
b. Decimal-to-Binary Encoder:
A decimal-to-binary encoder is used to convert decimal numbers (0-9) into their equivalent binary representation. It typically has four input lines for the decimal digits and a set of output lines representing the binary code.
- Decoders:
A decoder is a device that takes a coded input and produces multiple output lines based on the input code. It converts a binary code into a set of output signals.
a. Binary-to-Decimal Decoder:
A binary-to-decimal decoder is used to convert a binary code into its equivalent decimal representation. It takes binary inputs and activates the corresponding output line based on the input code.
b. 2-to-4 Decoder:
A 2-to-4 decoder takes two input lines and produces four output lines. The input code determines which output line is activated. For example, if the input code is 01, the first output line will be active.
c. 3-to-8 Decoder:
A 3-to-8 decoder takes three input lines and produces eight output lines. The input code determines which output line is activated. For example, if the input code is 101, the fifth output line will be active.
Decoders are often used in conjunction with multiplexers, memory systems, and address decoding circuits to select specific operations or memory locations based on the input code.
Encoders and decoders play crucial roles in digital systems by enabling data representation, manipulation, and control. They provide the means to convert between different data formats and facilitate efficient data transmission and processing.