Which code do rotational encoders use?

Rotational encoders primarily use Gray code for their operation, particularly because of the unique properties it offers. In Gray code, only one bit changes at a time as the value increments, which is particularly beneficial in eliminating errors during signal transitions. This characteristic becomes critical in applications like rotational encoders, where precise positioning is essential. For instance, when the encoder moves from one position to another, using Gray code helps to prevent misinterpretation of position during the transition phase.

Moreover, using Gray code reduces the chances of error that might occur if multiple bits change simultaneously, as would be the case with binary code. This feature provides increased reliability in applications where accurate position sensing is necessary, making Gray code the preferred choice for many rotational encoders.