Synaptics Incorporated
Proximity sensing with soft-synchronization to noise

Abstract:

An input device includes a capacitive proximity sensor and a processing system. The capacitive proximity sensor includes a multitude of transmitter electrodes and a multitude of receiver electrodes for proximity sensing in a sensing region. The processing system is configured to obtain a noisy sensor signal from the capacitive proximity sensor, extract a spike train in the noisy sensor signal, synchronize a pulse output of a pulse-generating circuit onto the spike train, and triggered by a first of a multitude of pulses of the pulse output, perform a first capacitive proximity sensing.