TOUCH SENSING METHOD AND APPARATUS

摘要

A method for measuring for generating a touch capacitance measurement is provided. Gain and offset control signals are generated, where the gain and offset control signals (VG, VOS) are adjusted to compensate for base capacitance of a touch sensor (202). The gain control signal (VG) is applied to a touch sensor (202) during a first phase of a clock signal (CLK1), and the offset control signal (Vos) is applied to an output circuit (209) during a second phase of the clock signal. The output circuit (209) is coupled to the touch sensor (202) during the second phase of the clock signal. The touch capacitance measurement is generated by compensating for the base capacitance with the gain and offset control signals, and a gain is applied to the touch capacitance measurement.