Patent ID: 8823399

Claim:
An apparatus comprising: a capacitance-sensing circuit coupled to a capacitive button comprising a first sense element and a second sense element, wherein the capacitance-sensing circuit is operative to measure signals from the first sense element and the second sense element with a sensing parameter set to a first value, wherein the signals correspond to capacitances of the first sense element and second sense element, and wherein an inner perimeter of the first sense element is disposed to surround an outer perimeter of the second sense element; and processing logic coupled to the capacitance-sensing circuit, wherein the processing logic is operative to: detect whether the first sense element is activated by a conductive object proximate to the capacitive button based on the measured signals; detect whether the second sense element is activated by the conductive object proximate to the capacitive button based on the measured signals; and adjust the first value to a second value for the sensing parameter when the second sense element is activated and the first sense element is not activated, wherein the capacitance-sensing circuit is operative to measure an additional signal from the second sense element with the sensing parameter set to the second value when the second sense element is activated and the first sense element is not activated and to measure additional signals from the first sense element and the second sense element with the sensing parameter set to the first value when the second sense element and first sense element are activated.