OPTIMIZING PIXEL SETTLING IN AN INTEGRATED DISPLAY AND CAPACITIVE SENSING DEVICE

• US 20170285793A1
• Filed: 03/30/2016
• Published: 10/05/2017
• Est. Priority Date: 03/30/2016
• Status: Active Grant

• Current Assignee: Synaptics Incorporated
• Original Assignee: Synaptics Incorporated
• Inventors: SHAMARAO, Prashant, REYNOLDS, Joseph Kurth, MOREIN, Stephen L.
• Granted Patent: US 9,836,173 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers
• 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 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• 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 example method of performing capacitive sensing and display updating in an integrated capacitive sensing device and display device includes driving a plurality of sensor electrodes of the capacitive sensing device for input sensing during a blanking period. The method further includes driving a plurality of source lines using a plurality of source drivers during the blanking period to update a first display line of the display device. The method further includes driving the plurality of source lines using the plurality of source drivers during a display update period to update one or more additional display lines of the display device. The method further includes adjusting an operational mode of the plurality of source drivers during the blanking period to equalize display pixel settling between the blanking period and the display update period.

Claims

1. A method of performing capacitive sensing and display updating in an integrated capacitive sensing device and display device, the method comprising:

driving a plurality of sensor electrodes of the capacitive sensing device for input sensing during a blanking period;

driving a plurality of source lines using a plurality of source drivers during the blanking period to update a first display line of the display device;

driving the plurality of source lines using the plurality of source drivers during a display update period to update one or more additional display lines of the display device; and

adjusting an operational mode of the plurality of source drivers during the blanking period to equalize display pixel settling between the blanking period and the display update period.

2. The method of claim 1, wherein the step of adjusting the operational mode of the plurality of source drivers comprises:

adjusting a slew rate of the plurality of source drivers during the blanking period.

3. The method of claim 2, wherein the step of adjusting the slew rate of the plurality of source drivers comprises:

setting the slew rate of the plurality of source drivers to a first slew rate for the first display line during the blanking period; and

setting the slew rate of the plurality of source drivers to a second slew rate for the one or more additional display lines during the display update period.

4. The method of claim 1, wherein the step of adjusting the operational mode of the plurality of source drivers comprises:

adjusting the drive time of the plurality of source drivers during the blanking period.

5. The method of claim 4, wherein the step of adjusting the drive time of the plurality of source drivers comprises:

controlling the plurality of source drivers to drive the plurality of source lines for substantially the same duration in each of the blanking period and the display update period.

6. The method of claim 1, wherein the step of adjusting the operational mode of the plurality of source drivers comprises:

adjusting a slew rate of the plurality of source drivers during the blanking period; and

adjusting the drive time of the plurality of source drivers during the blanking period.

7. The method of claim 1, wherein the blanking period comprises a long horizontal blanking period between a pair of display lines of the display device.

8. The method of claim 1, wherein each of the plurality of sensor electrodes comprises one or more common electrodes used for capacitive sensing and display updating, and wherein the step of driving the plurality of sensor electrodes for capacitive sensing comprises driving the common electrodes with modulated signals.

9. A processing system for a capacitive sensing device and a display device, comprising:

sensing circuitry configured to drive a plurality of sensor electrodes of the capacitive sensing device for input sensing during a blanking period;

a plurality of source drivers configured to drive a plurality of source lines to update a first display line of the display device during the blanking period and to update one or more additional display lines of the display device during a display update period; and

a controller, coupled to the plurality of source drivers, configured to adjust an operational mode of the plurality of source drivers during the blanking period to equalize display pixel settling between the blanking period and the display update period.

10. The processing system of claim 9, wherein the controller is configured to adjust the operational mode of the plurality of source drivers by adjusting a slew rate of the plurality of source drivers during the blanking period.

11. The processing system of claim 10, wherein the controller is configured to:

set the slew rate of the plurality of source drivers to a first slew rate for the first display line during the blanking period; and

set the slew rate of the plurality of source drivers to a second slew rate for the one or more additional display lines during the display update period.

12. The processing system of claim 9, wherein the controller is configured to adjust the operational mode of the plurality of source drivers by adjusting the drive time of the plurality of source drivers during the blanking period.

13. The processing system of claim 12, wherein controller is configured to:

control the plurality of source drivers to drive the plurality of source lines for substantially the same duration in each of the blanking period and the display update period.

14. The processing system of claim 9, wherein the controller is configured to adjust the operational mode of the plurality of source drivers by adjusting a slew rate of the plurality of source drivers during the blanking period and adjusting the drive time of the plurality of source drivers during the blanking period.

15. The processing system of claim 9, wherein the controller comprises a control circuit coupled to at least one control terminal of each of the plurality of source drivers.

16. An input device comprising a capacitive sensing device and a display device, the input device comprising:

a plurality of sensor electrodes;

a plurality of source lines; and

a processing system, coupled to the plurality of sensor electrodes and the plurality of source lines, the processing system including;

sensing circuitry configured to drive the plurality of sensor electrodes for input sensing during a blanking period;

a plurality of source drivers configured to drive the plurality of source lines to update a first display line of the display device during the blanking period and to update one or more additional display lines of the display device during a display update period; and

a controller, coupled to the plurality of source drivers, configured to adjust an operational mode of the plurality of source drivers during the blanking period to equalize display pixel settling between the blanking period and the display update period.

17. The input device of claim 16, wherein the controller is configured to adjust the operational mode of the plurality of source drivers by adjusting a slew rate of the plurality of source drivers during the blanking period.

18. The input device of claim 16, wherein the controller is configured to adjust the operational mode of the plurality of source drivers by adjusting the drive time of the plurality of source drivers during the blanking period.

19. The input device of claim 16, wherein the controller is configured to adjust the operational mode of the plurality of source drivers by adjusting a slew rate of the plurality of source drivers during the blanking period and adjusting the drive time of the plurality of source drivers during the blanking period

20. The input device of claim 16, wherein the controller comprises a control circuit coupled to at least one control terminal of each of the plurality of source drivers.