What are encoders?

What are Encoders?

Encoders are digital ICs used for encoding. By encoding, we mean generating a digital binary code for every input. An Encoder IC generally consists of an Enable pin which is usually set high to indicate the working. It consists of 2^n input lines and n output lines with each input line being represented by a code of zeros and ones which is reflected at the output lines.

In RF communication, the Encoder can also be used for converting parallel data to serial data.

Two Popular Encoder ICs

1. H12E

A popular example of an Encoder is the Holtek Encoder H12E used for parallel to serial conversion.

It is a type of CMOS IC with 8 address pins and 12 data pins. It is basically an 18 pin IC.  It is used in RF communication where it converts the 12 bit parallel data to serial form. It consists of an Enable pin which is active low pin and when set low, the transmission is enabled. The H12E encoder sends 4 words at a time. In other words, till the !TE pin is set low, the encoder transmits several cycles of each 4 words and stops the transmission once the !TE pin is set high.

Features of H12E

• Works with a supply voltage of 2.4 to 12 V.
• It is paired with H12 series of Decoders
• Consists of built in oscillators
• It is based on high noise immunity CMOS technology.
• It is used for remote controlled operations.

 2. HC148

 Another popular example of Encoder IC used as a priority Encoder is HC148 which is an 8 to 3 Line Priority Encoder. By Priority Encoder we refer to Encoders where a certain priority is given to each input and based on the level of priority the output code is generated. It also has an Enable pin which is active low pin and when set low, it enables the encoder operation. It works within the operating voltage range of 2 V to 6V.