A Rotary Encoder
Rotary encoders are used in many applications that require precise
shaft unlimited rotation
The picture above depicts the waveforms found at points A and B of encoder. Depending on which signal (A or B) transitions to next state ,the host can detect the direction. Each click or step is called a detent and is a stable position of the encoder.
A normal connection would like this:
R should be sized in 100s of KiloOhm because in stable state, it will be connected between ground and the supply.
Things to look for
Most important things to look in rotary incremental encoder:
- Number of detents per 360 degree rotation
- Current and voltage rating
- the rest such as mounting type, length of shaft etc.
- Bouncing time
- Min Phase difference between A and B
- Additional built in Switch