Patent ID: 8054299
Filing Date: 2011-11-08
Classification: G06F

Abstract:
1. A controller for a touch surface having a plurality of capacitive pixels, each capacitive pixel having a first electrode and a second electrode, different from the first electrode and defining a pixel capacitance therebetween, the controller comprising: stimulation circuitry for applying a stimulation voltage having a first and second voltage level to only the first electrode of at least some of the plurality of capacitive pixels, a plurality of detection circuits, one detection circuit corresponding to each channel defined as a group of capacitive pixels arranged along a given direction; each detection circuit comprising: wherein the hold signals from each channel are logically combined to indicate whether a charging or discharging of the capacitive pixels is in progress for any channel and wherein the stimulation circuitry is prevented from applying another stimulation voltage until the logically combined hold signals indicates that all channels have completed their respective charging and discharging.