Reduced noise by performing processing during low-noise periods of interfering circuitry

• US 10,365,762 B2
• Filed: 03/30/2016
• Issued: 07/30/2019
• Est. Priority Date: 03/30/2016
• Status: Active Grant

• Current Assignee: Synaptics Incorporated
• Original Assignee: Synaptics Incorporated
• Inventors: Shepelev, Petr, Weinerth, John Michael
• Primary Examiner(s): Lamb, Christopher R
• Application Number:
  US15/085,900
• Publication Number:
  US 20170285859A1
• Time in Patent Office: 1,217 Days
• Field of Search: None
• 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 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04184 Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

An input device, system, and processing system are disclosed for a display device with an integrated sensing device. The input device comprises a plurality of sensor electrodes, and a processing system coupled with the plurality of sensor electrodes. The processing system is configured to determine one or more low-noise periods associated with display update timing of the display device, and process, during the determined one or more low-noise periods, resulting signals received from the plurality of sensor electrodes.

Claims

1. An input device comprising:

a display device;

a plurality of sensor electrodes; and

a processing system coupled with the plurality of sensor electrodes and configured to;

receive resulting signals from the plurality of sensor electrodes during a first period;

determine a plurality of low-noise periods associated with display updating of the display device, and

process, using analog-to-digital conversion during the plurality of low-noise periods, the resulting signals received from the plurality of sensor electrodes during the first period, wherein the analog-to-digital conversion is performed as a plurality of iterations including first and second iterations, wherein the first iteration is performed during a first low-noise period of the plurality of low-noise periods and the second iteration is performed during a second low-noise period of the plurality of low-noise periods, and wherein the first low noise period and the first period are separated by a first delay corresponding to a high noise period and the first low noise period follows the first period.

2. The input device of claim 1, wherein the determined plurality of low-noise periods occur during one or more non-display update periods.

3. The input device of claim 2, wherein the determined plurality of low-noise periods occur during portions of the one or more non-display update periods in which capacitive sensing is not performed.

4. The input device of claim 1, wherein the determined plurality of low-noise periods correspond to reduced transients occurring on one or more of source electrodes and gate electrodes of the display device.

5. The input device of claim 1, wherein each of the plurality of sensor electrodes comprises at least one display electrode of the display device.

6. The input device of claim 1, wherein determining the plurality of low-noise periods comprises imposing a predetermined delay after detecting a transition between updating display lines of the display device.

7. A processing system comprising:

a display device;

display driver circuitry configured to update the display device based on display update timing of the display device;

sensor circuitry coupled with a plurality of sensor electrodes and configured to;

receive resulting signals from the plurality of sensor electrodes during a first period;

determine a plurality of low-noise periods associated with display updating of the display device, and

process, using analog-to-digital conversion during the plurality of low-noise periods, the resulting signals received from the plurality of sensor electrodes during the first period, wherein the analog-to-digital conversion is performed as a plurality of iterations including first and second iterations, wherein the first iteration is performed during a first low-noise period of the plurality of low-noise periods and the second iteration is performed during a second low-noise period of the plurality of low-noise periods, and wherein the first low noise period and the first period are separated by a first delay corresponding to a high noise period and the first low noise period follows the first period.

8. The processing system of claim 7, wherein the determined plurality of low-noise periods occur during one or more non-display update periods.

9. The processing system of claim 8, wherein the determined plurality of low-noise periods occur during portions of the one or more non-display update periods in which capacitive sensing is not performed.

10. The processing system of claim 7, wherein the determined plurality of low-noise periods correspond to reduced transients occurring on one or more of source electrodes and gate electrodes of the display device.

11. The processing system of claim 7, wherein each of the plurality of sensor electrodes comprises at least one display electrode of the display device.

12. The processing system of claim 7, wherein determining the plurality of low-noise periods comprises imposing a predetermined delay after detecting a transition between updating display lines of the display device.

13. A system comprising:

a processing system comprising analog-to-digital conversion (ADC) circuitry within a power domain; and

interfering circuitry within the power domain,

wherein the processing system is configured to;

receive resulting signals from a plurality of sensor electrodes during a receiving period;

determine one or more discrete noise events produced by the interfering circuitry, and;

control the ADC circuitry to perform ADC operations to process the resulting signals during a plurality of time periods during which the one or more discrete noise events do not occur, wherein the ADC operations are performed as a plurality of iterations including first and second iterations, wherein the first iteration is performed during a first time period of the plurality of time periods and the second iteration is performed during a second time period of the plurality of time periods, and wherein the first time period and the receiving period are separated by a first delay corresponding to a high noise period and the first time period follows the receiving period.

14. The system of claim 13, wherein the interfering circuitry comprises one of a processor and memory, and wherein the one or more discrete noise events comprise one of code execution and memory operation.

15. The system of claim 14, wherein the interfering circuitry comprises a processor and the one or more discrete noise events comprise code execution by the processor, wherein the processing system is further configured to stall the code execution during the plurality of time periods.

16. The system of claim 13, wherein the ADC circuitry is included in a receiver of the processing system, wherein the interfering circuitry is separately included in the receiver, wherein the processing system controls the ADC circuitry to perform ADC operations when the receiver is in a predetermined steady-state.