What is an Encoder?

An encoder may be a sensor of mechanical motion that generates digital signals in response to the motion. As an electro-mechanical device, an encoder is in a position to supply motion system users with information concerning position, velocity, and direction. encoder responds to motion along a path, while a rotary encoder responds to rotational motion. An encoder is usually categorized by the means of its output. An incremental encoder generates a train of pulses that may be wont to determine position and speed. An absolute encoder generates unique bit configurations to trace positions directly.

How Rotary Encoder Works

Let’s take a better check out the encoder and see its working rule. Here’s how the square wave pulses are generated: A rotary encoder may be a sort of position sensor which is employed for determining the position of a shaft. It generates an electrical signal, either analog or digital, consistent with the rotational movement.

The encoder features a disk with evenly spaced contact zones that are connected to the common pin C and two other separate contact pins A and B, as illustrated below.


A rotary encoder (M274) is a type of position sensor which is used for determining the angular position of a rotating shaft. It generates an electrical signal, either analog or digital, according to the rotational movement.


S/L PIN Description
1 GND Ground or Arduino Board
2 +Vcc 5V DC Power Supply
3 SW Output of Internal
4 DT Contact A Output or Data
5 CLK Contact B output or Data


  1. Long life.
  2. Easy interface
  3. 360º free rotation.
  4. Incremental type encoder
  5. Can work on low voltages
  6. 20 steps or cycles per revolution
  7. Maximum operating temperature: 0°C to + 80°C


  1. Motors
  2. Robotic arms
  3. Hobby projects.
  4. Security systems.
  5. Vending machines.
  6. Industrial machines.
  7. Engineering systems.
  8. Measuring instruments.
  9. Systems where systematic change INPUT device is needed like CROs, signal generator, etc.