LOW POWER TOUCH SENSING DURING A SLEEP STATE OF AN ELECTRONIC DEVICE

• US 20180088733A1
• Filed: 08/30/2017
• Published: 03/29/2018
• Est. Priority Date: 09/23/2016
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: SYED, Taif A., YANG, Bingrui, MULLENS, Christopher Tenzin, RANGANATHAN, Sumant
• Granted Patent: US 10,928,881 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 1/3215 Monitoring of peripheral devices
• CPC Class Codes: G06F 1/3262 Power saving in digitizer or tablet
• CPC Class Codes: G06F 2203/04104 Multi-touch detection in digitiser, i.e. details about the simultaneous detection of a plurality of touching locations, e.g. multiple fingers or pen and finger
• CPC Class Codes: G06F 2203/04108 Touchless 2D- digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface without distance measurement in the Z direction
• CPC Class Codes: G06F 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes

Abstract

An electronic device is disclosed. The electronic device can sense touch on its touch screen while in a sleep state in a manner that allows the electronic device to respond to certain touch inputs, while consuming less power due to touch sensing than while in an awake state. For example, sensing touch during the sleep state can allow the electronic device to wake (e.g., transition from the sleep state to the awake state) in response to detecting a certain touch input (e.g., a tap or other touch input) on its touch screen while in the sleep state. Various ways for the electronic device to sense touch during the sleep state are disclosed.

Claims

1. A touch controller comprising:

sense circuitry configured to sense touch at one or more touch electrodes on a touch sensor panel; and

a touch processor configured to;

while an electronic device is in a first state during which a first component of the electronic device is in a first power state, cause the sense circuitry to sense touch at the one or more touch electrodes using one or more first touch scan steps having a first length; and

while the electronic device is in a second state, different from the first state, during which the first component of the electronic device is in a second power state, different from the first power state, cause the sense circuitry to sense touch at the one or more touch electrodes, for transitioning the electronic device from the second state to the first state, using one or more second touch scan steps having a second length, shorter than the first length.

2. The touch controller of claim 1, wherein the first state comprises an awake state of the electronic device, and the second state comprises a sleep state of the electronic device.

3. The touch controller of claim 1, wherein the touch processor is further configured to, while the electronic device is in the second state:

in response to causing the sense circuitry to sense touch at the one or more touch electrodes using the one or more second touch scan steps;

in accordance with a determination that the sense circuitry senses touch activity at the one or more touch electrodes;

lengthen the one or more second touch scan steps; and

determine whether the touch activity corresponds to a touch input for transitioning the electronic device from the second state to the first state based on the lengthened one or more second touch scan steps; and

in accordance with a determination that the sense circuitry does not sense touch activity at the one or more touch electrodes, maintaining the second length of the one or more second touch scan steps.

4. The touch controller of claim 3, wherein lengthening the one or more second touch scan steps comprises incrementally lengthening the one or more second touch scan steps until the touch processor is able to identify the touch activity at the one or more touch electrodes.

5. The touch controller of claim 3, wherein the touch processor is further configured to, while the electronic device is in the second state:

in accordance with the determination that the sense circuitry senses touch activity at the one or more touch electrodes, reduce an amount of ganging of the one or more touch electrodes.

6. The touch controller of claim 1, wherein the touch processor is further configured to, while the electronic device is in the second state:

determine an amount of touch sensing noise at the touch sensor panel;

in accordance with a determination that the amount of touch sensing noise is greater than a noise threshold;

lengthen the one or more second touch scan steps; and

determine whether the touch activity corresponds to a touch input for transitioning the electronic device from the second state to the first state based on the lengthened one or more second touch scan steps; and

in accordance with a determination that the amount of touch sensing noise is less than the noise threshold;

maintain the second length of the one or more second touch scan steps; and

determine whether the touch activity corresponds to a touch input for transitioning the electronic device from the second state to the first state based on the maintained one or more second touch scan steps.

7. The touch controller of claim 6, wherein lengthening the one or more second touch scan steps comprises incrementally lengthening the one or more second touch scan steps until the touch processor is able to identify the touch activity at the one or more touch electrodes.

8. The touch controller of claim 1, wherein the touch controller is integrated within an electronic device that comprises a touch screen, the touch screen including the touch sensor panel.

9. The touch controller of claim 1, wherein:

the first component of the electronic device is a display of the electronic device,

the first power state of the display is a high power state of the display, and

the second power state of the display is a low power state of the display.

10. A touch controller comprising:

sense circuitry configured to sense touch at one or more touch electrodes on a touch sensor panel; and

a touch processor configured to;

while an electronic device is in a first state during which a first component of the electronic device is in a first power state, cause the sense circuitry to sense touch at the one or more touch electrodes using a first touch sensing frequency selected from a first number of candidate touch sensing frequencies; and

while the electronic device is in a second state, different from the first state, during which the first component of the electronic device is in a second power state, different from the first power state, cause the sense circuitry to sense touch at the one or more touch electrodes, for transitioning the electronic device from the second state to the first state, using a second touch sensing frequency selected from a second number of candidate touch sensing frequencies, less than the first number of candidate touch sensing frequencies.

11. The touch controller of claim 10, wherein the first state comprises an awake state of the electronic device, and the second state comprises a sleep state of the electronic device.

12. The touch controller of claim 10, wherein the touch processor is further configured to:

while the electronic device is in the first state, store baseline touch data for each of the first number of candidate touch sensing frequencies at a first periodicity; and

while the electronic device is in the second state, store baseline touch data for each of the second number of candidate touch sensing frequencies at a second periodicity, less than the first periodicity.

13. The touch controller of claim 12, wherein the baseline touch data for each of the first number of candidate touch sensing frequencies and the baseline touch data for each of the second number of candidate touch sensing frequencies corresponds to touch data indicative of no touch activity.

14. The touch controller of claim 10, wherein the second number of candidate touch sensing frequencies is a subset of the first number of candidate touch sensing frequencies.

15. The touch controller of claim 10, wherein the touch controller is integrated within an electronic device that comprises a touch screen, the touch screen including the touch sensor panel.

16. The touch controller of claim 10, wherein:

the first component of the electronic device is a display of the electronic device,

the first power state of the display is a high power state of the display, and

the second power state of the display is a low power state of the display.

17. A touch controller comprising:

sense circuitry configured to sense touch at one or more touch electrodes on a touch sensor panel; and

a touch processor configured to, while an electronic device is in a first state during which the sense circuitry senses touch at the one or more touch electrodes for transitioning the electronic device from the first state to a second state, wherein in the first state a first component of the electronic device is in a first power state, and in the second state the first component of the electronic device is in a second power state, different from the first power state;

periodically cause the sense circuitry to perform a scan of a first scan type of the touch sensor panel;

in response to determining that a respective scan of the first scan type of the touch sensor panel is indicative of touch activity on the touch sensor panel, cause the sense circuitry to perform a scan of a second scan type, different than the first scan type, of the touch sensor panel to determine whether the touch activity corresponds to a touch input for transitioning the electronic device from the first state to the second state; and

in response to determining that the respective scan of the first scan type of the touch sensor panel is not indicative of touch activity on the touch sensor panel;

in accordance with a determination that a first condition is satisfied, forgo causing the sense circuitry to perform the scan of the second scan type of the touch sensor panel; and

in accordance with a determination that the first condition is not satisfied, cause the sense circuitry to perform the scan of the second scan type of the touch sensor panel to update baseline touch data based on the scan of the second scan type of the touch sensor panel.

18. The touch controller of claim 17, wherein the first state comprises an awake state of the electronic device, and the second state comprises a sleep state of the electronic device.

19. The touch controller of claim 17, wherein:

performing the scan of the first scan type of the touch sensor panel comprises performing a single scan of the touch sensor panel; and

performing the scan of the second scan type of the touch sensor panel comprises performing a plurality of scans of the touch sensor panel.

20. The touch controller of claim 17, wherein the first condition is not satisfied when a time since a last update of the baseline touch data is greater than a threshold amount.

21. The touch controller of claim 17, wherein the touch processor is further configured to:

during the scan of the first scan type of the touch sensor panel, disregard touch input sensed by sense circuitry corresponding to one or more touch electrodes at one or more edges of the touch sensor panel.

22. The touch controller of claim 21, wherein the touch processor is further configured to:

during the scan of the first scan type of the touch sensor panel, power down the sense circuitry corresponding to the one or more touch electrodes at the one or more edges of the touch sensor panel.

23. The touch controller of claim 17, wherein the touch processor is further configured to:

during the scan of the first scan type of the touch sensor panel, power down drive circuitry corresponding to one or more touch electrodes at one or more edges of the touch sensor panel.

24. The touch controller of claim 17, wherein the touch controller is integrated within an electronic device that comprises a touch screen, the touch screen including the touch sensor panel.

25. The touch controller of claim 17, wherein:

the first component of the electronic device is a display of the electronic device,

the first power state of the display is a high power state of the display, and

the second power state of the display is a low power state of the display.

26. The touch controller of claim 17, wherein the touch processor is further configured to:

in response to determining that the touch activity corresponds to the touch input for transitioning the electronic device from the first state to the second state, transitioning the electronic device from the first state to the second state.

27. A method for sensing touch on a touch sensor panel, the method comprising:

while an electronic device is in a first state during which a first component of the electronic device is in a first power state, sensing touch at one or more touch electrodes on the touch sensor panel using one or more first touch scan steps having a first length; and

while the electronic device is in a second state, different from the first state, during which the first component of the electronic device is in a second power state, different from the first power state, sensing touch at the one or more touch electrodes, for transitioning the electronic device from the second state to the first state, using one or more second touch scan steps having a second length, shorter than the first length.

28. A method for sensing touch on a touch sensor panel, the method comprising:

while an electronic device is in a first state during which a first component of the electronic device is in a first power state, sensing touch at one or more touch electrodes on the touch sensor panel using a first touch sensing frequency selected from a first number of candidate touch sensing frequencies; and

while the electronic device is in a second state, different from the first state, during which the first component of the electronic device is in a second power state, different from the first power state, cause the sense circuitry to sense touch at the one or more touch electrodes, for transitioning the electronic device from the second state to the first state, using a second touch sensing frequency selected from a second number of candidate touch sensing frequencies, less than the first number of candidate touch sensing frequencies.

29. A method for sensing touch on a touch sensor panel, the method comprising:

while an electronic device is in a first state during which touch is sensed at one or more touch electrodes for transitioning the electronic device from the first state to a second state, wherein in the first state a first component of the electronic device is in a first power state, and in the second state the first component of the electronic device is in a second power state, different from the first power state;

periodically performing scan of a first scan type of the touch sensor panel;

in response to determining that a respective scan of the first scan type of the touch sensor panel is indicative of touch activity on the touch sensor panel, performing a scan of a second scan type, different than the first scan type, of the touch sensor panel to determine whether the touch activity corresponds to a touch input for transitioning the electronic device from the first state to the second state; and

in response to determining that the respective scan of the first scan type of the touch sensor panel is not indicative of touch activity on the touch sensor panel;

in accordance with a determination that a first condition is satisfied, forgoing performing the scan of the second scan type of the touch sensor panel; and

in accordance with a determination that the first condition is not satisfied, performing the scan of the second scan type of the touch sensor panel to update baseline touch data based on the scan of the second scan type of the touch sensor panel.