Texas Instruments Incorporated
Using driven shield and touch elements lock algorithm for achieving liquid tolerant capacitive touch solution

Abstract:

An apparatus includes a touch interface that includes a plurality of electrodes and a shield device. The shield device is configured to establish a first mutual capacitive coupling with a first electrode of the plurality of electrodes. The shield device is further configured to establish a second mutual capacitive coupling with a second electrode of the plurality of electrodes. The apparatus further includes a controller coupled to the touch interface. The controller is configured to detect a touch based on a detected first capacitance value of the first mutual capacitive coupling and a detected second capacitance value of the second mutual capacitive coupling.