Auto Scanning for Multiple Frequency Stimulation Multi-Touch Sensor Panels
First Claim
1. A method for detecting whether a touch event has occurred on a touch sensor panel, comprising:
- while maintaining a panel processor in an inactive state,simultaneously driving a first group of rows of the touch sensor panel with one or more stimulation signals,determining whether an output of one or more sense channels coupled to one or more columns of the touch sensor panel exceeds a predetermined threshold indicative of a touch event, andif the output exceeds the threshold, triggering a subsequent capture of touch data for determining a location of the touch event.
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Accused Products
Abstract
The use of multiple stimulation frequencies and phases is disclosed to detect touch events on a touch sensor panel in a low-power state. Simultaneously during every frame, a number of rows of the touch sensor panel can be driven with a positive phase of one or more stimulation signals, and the same number of different rows can be driven with the anti-phase of those same stimulation signals. Because the same number of rows are stimulated with the in-phase and anti-phase components of the one or more stimulation signals, the resulting charges injected into a given column cancel each other out. However, a touch event will create an imbalance, and a non-zero charge will be detected. The detection of the touch event can then trigger the system to wake up, activate a panel processor, and perform a full panel scan, where the location of the touch event can be identified.
278 Citations
28 Claims
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1. A method for detecting whether a touch event has occurred on a touch sensor panel, comprising:
while maintaining a panel processor in an inactive state, simultaneously driving a first group of rows of the touch sensor panel with one or more stimulation signals, determining whether an output of one or more sense channels coupled to one or more columns of the touch sensor panel exceeds a predetermined threshold indicative of a touch event, and if the output exceeds the threshold, triggering a subsequent capture of touch data for determining a location of the touch event. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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13. An apparatus for detecting whether a touch event has occurred on a touch sensor panel, comprising:
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driver logic configured for providing stimulation signals to drive rows of the touch sensor panel; a plurality of sense channels configured for detecting touch events on the touch sensor panel; and auto-scan scan logic coupled to the driver logic and the plurality of sense channels, the auto-scan logic configured for during an auto-scan cycle, and while maintaining a panel processor in an inactive state, periodically triggering the driver logic to simultaneously drive a first group of rows of the touch sensor panel with one or more first stimulation signals, determining whether an output of one or more sense channels exceeds a predetermined threshold indicative of a touch event, and if the output exceeds the threshold, triggering a subsequent capture of touch data for determining a location of the touch event. - View Dependent Claims (14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26)
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27. A mobile telephone including an apparatus for detecting whether a touch event has occurred on a touch sensor panel, the apparatus comprising:
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driver logic configured for providing stimulation signals to drive rows of the touch sensor panel; a plurality of sense channels configured for detecting touch events on the touch sensor panel; and auto-scan scan logic coupled to the driver logic and the plurality of sense channels, the auto-scan logic configured for during an auto-scan cycle, and while maintaining a panel processor in an inactive state, periodically triggering the driver logic to simultaneously drive a first group of rows of the touch sensor panel with one or more first stimulation signals, determining whether an output of one or more sense channels exceeds a predetermined threshold indicative of a touch event, and if the output exceeds the threshold, triggering a subsequent capture of touch data for determining a location of the touch event.
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28. A digital audio player including an apparatus for detecting whether a touch event has occurred on a touch sensor panel, the digital audio player comprising:
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driver logic configured for providing stimulation signals to drive rows of the touch sensor panel; a plurality of sense channels configured for detecting touch events on the touch sensor panel; and auto-scan scan logic coupled to the driver logic and the plurality of sense channels, the auto-scan logic configured for during an auto-scan cycle, and while maintaining a panel processor in an inactive state, periodically triggering the driver logic to simultaneously drive a first group of rows of the touch sensor panel with one or more first stimulation signals, determining whether an output of one or more sense channels exceeds a predetermined threshold indicative of a touch event, and if the output exceeds the threshold, triggering a subsequent capture of touch data for determining a location of the touch event.
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Specification