Patent attributes
The use of multiple stimulation signals having one or more frequencies and one or more phases to generate an image of touch on a touch sensor panel is disclosed. Each of a plurality of sense channels can be coupled to a column in a touch sensor panel and can have one or more mixers. Each mixer in the sense channel can utilize a circuit capable generating a demodulation frequency of a particular frequency. At each of multiple steps, various phases of one or more selected frequencies can be used to simultaneously stimulate the rows of the touch sensor panel, and the one or more mixers in each sense channel can be configured to demodulate the signal received from the column connected to each sense channel using the one or more selected frequencies. After all steps have been completed, the demodulated signals from the one or more mixers can be used in calculations to determine an image of touch for the touch sensor panel at each of the one or more frequencies.
