US Patent 9946404 LED screen noise sensing for discreet capacitive sensors

Embodiments herein provide input devices that include an LED display panel on which a discreet capacitive sensor is disposed to form a capacitive sensing region. The capacitive sensor includes a plurality of sensor electrodes that are used to generate capacitive sensing signals indicating user interaction with the input device. In one embodiment, the sensor electrodes are disposed on a cathode layer in the LED display panel such that the sensor electrodes are capacitively coupled to the LED display panel. Currents in the cathode layer can cause interference or noise when performing capacitive sensing. The input devices include an analog front end channel for measuring interference resulting from the cathode layer at the same time receivers measure capacitive sensing signals using the sensor electrodes. The input device may process the capacitive sensing signals differently depending on the measured interference.