Increasing the Dynamic Range of an Integrator Based Mutual-Capacitance Measurement Circuit

摘要

In one embodiment, a device includes one or more processors and one or more memory units. The one or more memory units collectively store logic configured to cause the one or more processors to perform operations including obtaining a first measurement associated with a first voltage, the first voltage output by the mutual-capacitance measurement circuit in response to a first change in capacitance, and obtaining a second measurement associated with a second voltage, the second voltage output by the mutual-capacitance measurement circuit in response to a second change in capacitance. The operations further include calculating a differential measurement using a difference between the first measurement and the second measurement and determining whether a touch or proximity event has occurred based at least in part on the calculated differential measurement.