3.3.7 Hysteresis

Under severe noise conditions, the delta value can hover around the sensor threshold and cause the sensor to dither in and out of touch. To avoid this, once a sensor goes into the Detect state, the Threshold for the sensor is reduced by the hysteresis value, thus providing a configurable margin for the noise. Hysteresis values are derived from the Threshold is defined as a percentage of the Threshold. In other words - buttons go into touch with a higher threshold than they go out of touch.

It is not enough for the delta to go below the Threshold for the sensor to report out-of-touch. It has to go below the hysteresis level to declare no touch.

Steps to Configure Hysteresis

The hysteresis value for Button N can be updated by writing in the Channel Hysteresis (HYSTERESIS[n]) register. Refer to the Configuration Summary for more details.