Granted Patent B2

US 12,229,370 · App. 18/459,249 · Granted Feb 18, 2025

Inventors: Pengcheng Wen (Beijing, CN); Yuan Yun Wang (New Taipei, TW)

Assignees: STMICROELECTRONICS LTD.; STMICROELECTRONICS (BEIJING) R&D CO., LTD

G06F3/04184G06F3/04166G06F3/0443G09G3/3233G09G2320/0247G09G2330/023G09G2354/00

Abstract

Claims (30)

1. A method of operating a touchscreen, the method comprising:

performing a first synchronized touch scan pattern with a controller coupled to a display, the controller comprising a first processing chip, the first synchronized touch scan pattern being scheduled to avoid touch scans coinciding with refreshes of the display performed at a first display refresh rate, wherein a display controller provides synchronization pulses to the controller while performing at the first display refresh rate, the display controller comprising a second processing chip, the synchronization pulses being separated by a first interval;

upon detecting a pair of synchronization pulses being separated by a second interval, the second interval being different from the first interval, obtaining a second display refresh rate from the second interval; and

performing a second synchronized touch scan pattern with the controller coupled to the display, the second synchronized touch scan pattern being scheduled to avoid touch scans coinciding with refreshes of the display performed at the second display refresh rate.

2. The method of claim 1 , further comprising cancelling a last touch scan of the first synchronized touch scan pattern upon receiving a first synchronization pulse of the pair of synchronization pulses while the last touch scan is being performed.

3. The method of claim 1 , wherein the controller is configured to obtain the second display refresh rate independently of notification of a change from the first display refresh rate to the second display refresh rate.

4. The method of claim 1 , further comprising performing a non-synchronized touch scan pattern with the controller coupled to the display upon receiving a first synchronization pulse of the pair of synchronization pulses.

5. The method of claim 1 , further comprising performing a non-synchronized touch scan pattern with the controller coupled to the display upon startup of the controller.

6. The method of claim 5 , further comprising ending the non-synchronized touch scan pattern after obtaining the first display refresh rate from synchronization pulses provided from the display controller to the controller.

7. The method of claim 1 , wherein the synchronization pulses are vertical synchronization pulses.

8. The method of claim 1 , wherein the synchronization pulses are horizontal synchronization pulses.

9. A method of operating a touchscreen, the method comprising:

performing a first synchronized touch scan pattern with a controller coupled to a display, the controller comprising a first processing chip, the first synchronized touch scan pattern being scheduled to avoid touch scans coinciding with refreshes of the display performed at a first display refresh rate;

detecting a pair of synchronization pulses being separated by an interval;

obtaining a second display refresh rate from the interval, the second display refresh rate being different from the first display refresh rate; and

performing a second synchronized touch scan pattern with the controller coupled to the display while the display is refreshed at the second display refresh rate.

10. The method of claim 9 , further comprising, after detecting a first synchronization pulse of the pair of synchronization pulses, performing a non-synchronized touch scan pattern with the controller coupled to the display.

11. The method of claim 10 , wherein the non-synchronized touch scan pattern schedules touch scans independent of a refresh rate of the display.

12. The method of claim 9 , wherein the touchscreen is part of a smartphone.

13. The method of claim 9 , wherein the display comprises low-temperature polycrystalline oxide.

14. The method of claim 9 , wherein the pair of synchronization pulses are vertical synchronization pulses sent from a display controller, the display controller comprising a second processing chip.

15. A method of operating a touchscreen, the method comprising:

performing a first synchronized touch scan pattern with a controller coupled to a display, the controller comprising a first processing chip, the first synchronized touch scan pattern being scheduled to avoid touch scans coinciding with refreshes of the display performed at a first display refresh rate, a display controller providing synchronization pulses to the controller while performing at the first display refresh rate, the display controller comprising a second processing chip, the synchronization pulses being separated by a first interval;

upon detecting a pair of synchronization pulses being separated by a second interval, the second interval being different from the first interval, obtaining a second display refresh rate from the second interval independently of a notification from the display controller of the second display refresh rate; and

performing a second synchronized touch scan pattern with the controller coupled to the display, the second synchronized touch scan pattern being scheduled to avoid touch scans coinciding with refreshes of the display performed at the second display refresh rate.

16. The method of claim 15 , wherein performing the first synchronized touch scan pattern and the second synchronized touch scan pattern reduces display flicker.

17. The method of claim 15 , wherein the pair of synchronization pulses are vertical synchronization pulses.

18. The method of claim 15 , wherein the pair of synchronization pulses are horizontal synchronization pulses.

19. The method of claim 15 , wherein the display comprises organic light emitting diodes.

20. The method of claim 15 , wherein the display comprises low-temperature polycrystalline oxide.

Assignments (2)

Continuity (2)

References Cited (17)