Frequency agile touch processing

摘要

A touch input device configured to maintain system performance despite a changing master clock frequency is provided. The touch input device includes one or more agile clocking dynamic scaling engines that can detect changes in the frequency of the master clock and can scale parameters of the touch controller associated with touch detection such that time domain to maintain uniform system performance.

主权项

1. A touch controller comprising:
an oscillator section configured to provide a master clock signal and change a frequency of the master clock signal in response to a command; a plurality of touch sensing sections configured to receive the master clock signal from the oscillator section and perform functions associated with generating stimulation signals and receiving and detecting signals indicative of a touch event, the plurality of touch sensing sections including one or more time dependent parameters and one or more sample domain parameters; and a processor capable of:
calculating one or more baseline values associated with the plurality of touch sensing sections;calculating an initial value for each of the one or more time dependent parameters and the one or more sample domain parameters;detecting changes in the frequency of the master clock signal;recalculating the one or more baseline values associated with the plurality of touch sensing sections;recalculating the one or more values of the one or more sample domain parameters in response to the detected change in the master clock frequency such that one or more values of the one or more time dependent parameters remain constant; andperforming a touch scan to detect a touch input event based on the one or more recalculated baseline values and the one or more recalculated sample domain parameters.