Patent ID: 10061437

Abstract:
Techniques for removing display-based corrupting components from a capacitive sensing signal when display and capacitive sensing is performed at or nearly at the same time. A routing carrying display related signals (e.g., a source signal for sub-pixel updating) may induce a corrupting current into a routing for carrying capacitive sensing signals. This corrupting current would reduce the ability to determine presence of an input object via the sensing signal. Therefore, the corrupting signal is effectively removed from a signal received from a sensor electrode when driven for sensing. The corrupting component may be removed either in analog or digitally. In analog, the corrupting component is removed via a tunable capacitance. Digitally, a corrupting component is calculated as an impulse response convolved with the source driver voltage. This corrupting component is then subtracted from a digital value output by the sensing circuitry to obtain a “clean” value.