Patent ID: 8884920
Filing Date: 2014-11-11
Classification: G06F

Abstract:
1. A method for determining whether a user is interacting with a capacitive sense element, the method comprising: executing a first set of instructions that drive, for a duration of time, an output to a predetermined state effective to charge the capacitive sense element; subsequent to the output being driven for the duration of time effective to charge the capacitive sense element, executing a second set of instructions that monitor, via an input, a voltage level of the capacitive sense element as the charge on the capacitive sense element changes, wherein the second set of instructions are executed for a number of iterations until the voltage level of the capacitive sense element, as monitored via the input, crosses a predefined threshold; subtracting a bias value from the number of iterations that the second set of instructions execute to provide a biased number of iterations; adding an offset to the biased number of iterations that the second set of instructions execute to ensure a positive comparison; and determining whether the user is interacting with the capacitive sense element by comparing the offset number of iterations that the second set of instructions execute with a reference value that indicates user interaction when met or exceeded.