Capacitive sensing during non-display update times

摘要

Embodiments of the invention generally provide an input device with display screens that periodically update (refresh) the screen by selectively driving common electrodes corresponding to pixels in a display line. In general, the input devices drive each electrode until each display line (and each pixel) of a display frame is updated. In addition to updating the display, the input device may perform capacitive sensing using the display screen as a proximity sensing area. To do this, the input device may interleave periods of capacitive sensing between periods of updating the display based on a display frame. For example, the input device may update the first half of display lines of the display screen, pause display updating, perform capacitive sensing, and finish updating the rest of the display lines. Further still, the input device may use common electrodes for both updating the display and performing capacitive sensing.

主权项

1. A processing system for a display device comprising an integrated capacitive sensing device, the processing system comprising:
a driver module comprising driver circuitry, the driver module coupled to a plurality of sensor electrodes, wherein each of the plurality of sensor electrodes comprises at least one common electrode of a plurality of common electrodes configured to be driven for updating a display of a display device and capacitive sensing during a display frame, wherein the display frame comprises a plurality of display line update periods, a first plurality of blanking periods and a second plurality of blanking periods, wherein each of the second plurality of blanking periods occurs between respective pairs of the plurality of display line update periods, and wherein each of the second plurality of blanking periods is longer than each of the first plurality of blanking periods; and wherein the driver module is configured to drive a first sensor electrode of the plurality of sensor electrodes for capacitive sensing during a first one of the second plurality of blanking periods.