Patent ID: 8830201

Claim:
An equalized capacitive touchpad, comprising: a touch sensor having M first sensing lines in a first direction and N second sensing lines in a second direction with M×N mutual capacitances therebetween, where M and N are integers larger than one; a controller coupled to the N second sensing lines, the controller comprising a front-end circuit for detecting the M×N mutual capacitances to generate M×N sensed values; and an equalizer coupled to the front-end circuit, having M×N equalization values respectively corresponding to the M×N mutual capacitances between the M first sensing lines and the N second sensing lines, for determining a corresponding equalization value according to position information of a detected mutual capacitance, and correcting the sensed value with the corresponding equalization value to obtain a corrected sensed value; wherein the equalization values are for compensating for resistor-capacitance filtering effect, and the corresponding equalization value increases as the detected mutual capacitance is more distant from the controller; and wherein the corrected sensed value is used to determine a touched position.