Integrated touch sensitive display gate driver

• US 8,537,126 B2
• Filed: 08/21/2009
• Issued: 09/17/2013
• Est. Priority Date: 04/06/2009
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Yousefpor, Marduke, Chang, Shih Chang, White, Kevin J., Hotelling, Steven Porter
• Primary Examiner(s): Giesy, Adam R
• Assistant Examiner(s): HEYI, HENOK G
• Application Number:
  US12/545,669
• Publication Number:
  US 20100253638A1
• Time in Patent Office: 1,488 Days
• Field of Search: None
• US Class Current: 345/173
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• 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 3/04184 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

Abstract

A gate driver circuit for switching gate line voltage supplies between display and touch modes is disclosed. The circuit can include one or more switches configured to switch one or more gate lines of an integrated touch sensitive display between a display mode and a touch mode. During touch mode, the circuit can be configured to switch the gate lines to connect to a more stable voltage supply. The circuit can also be configured to reduce or eliminate interference from the display circuitry to the touch circuitry that could affect touch sensing. During display mode, the circuit can be configured to switch the gate lines to connect to a fluctuating voltage supply.

Claims

1. A touch sensitive display comprising:

a first drive region comprising a first plurality of display pixels;

a second drive region comprising a second plurality of display pixels;

a sense region disposed between the first and second drive regions and comprising a third plurality of display pixels;

conductive lines electrically connecting together at least some of the display pixels of the first and second drive regions along first and second directions and electrically bypassing the third plurality of display pixels in the sense region;

each display pixel having a gate, wherein a plurality of display pixels have their gates connected to a gate line; and

at least one switch configured to switch the gate line between a first configuration and a second configuration, the first configuration for switchably connecting the gate line to a first voltage during a display function and the second configuration for switchably connecting the gate line to a second voltage during a touch sensing function, the second voltage being different from the first voltage.

2. The circuit of claim 1, wherein the first configuration comprises the gate line being switched to receive a display voltage signal generated by the display circuitry.

3. The circuit of claim 1, wherein the second configuration comprises the gate line being switched to receive a touch voltage signal generated by the touch circuitry.

4. The circuit of claim 1, wherein the second configuration comprises the gate line being switched to receive an active ground voltage signal from the touch circuitry.

5. The circuit of claim 1, wherein the second configuration comprises the voltage on the another voltage supply being sensed and adjusted to reduce interference from the display circuitry.

6. The circuit of claim 1, wherein the second configuration comprises a logic state of the display being held so that the logic state can be accessed when the display switches to the first configuration.

7. The circuit of claim 1, wherein the second configuration comprises a display clock being disabled during the second configuration.

8. The circuit of claim 1 incorporated into at least one of a mobile telephone, a digital media player, or a personal computer.

9. A method for use in an integrated touch sensitive display, the method comprising:

providing a first drive region comprising a first plurality of display pixels;

providing a second drive region comprising a second plurality of display pixels;

providing a sense region disposed between the first and second drive regions and comprising a third plurality of display pixels;

providing conductive lines electrically connecting together at least some of the display pixels of the first and second drive regions along first and second directions and electrically bypassing the third plurality of display pixels in the sense region;

providing a gate for each display pixel,

providing a gate line, wherein a plurality of display pixels have their gates connected to the gate line;

receiving a signal indicative of one of a display mode and a touch mode;

configuring the gate line of the display to connect to a first voltage supply during the display mode based on the received signal; and

configuring the gate line to connect to a second voltage supply during the touch mode based on the received signal.

10. The method of claim 9, wherein a voltage from the first voltage supply is incompatible with the touch mode.

11. The method of claim 9, wherein the configuring to the first voltage supply comprises configuring the gate line to connect to a display driver during displaying of an image on the display.

12. The method of claim 9, wherein the configuring to the second voltage supply comprises configuring the gate line to connect to a touch circuit during sensing of a touch on the display.

13. The method of claim 9, wherein the configuring to the second voltage supply comprises configuring the gate line to connect to an active ground during sensing of a touch on the display.

14. An integrated touch sensitive display comprising:

a first drive region comprising a first plurality of display pixels;

a second drive region comprising a second plurality of display pixels;

a sense region disposed between the first and second drive regions and comprising a third plurality of display pixels;

conductive lines electrically connecting together at least some of the display pixels of the first and second drive regions along first and second directions and electrically bypassing the third plurality of display pixels in the sense region;

each display pixel having a gate, wherein a plurality of display pixels have their gates connected to a gate line; and

a circuit having at least one switch configured to switchably transmit a first voltage from a first voltage source to the gate line during a display mode of the display and a second voltage from a second voltage source to the gate line during a touch mode of the display.

15. The display of claim 14, further comprising:

a display driver configured to send the first voltage to the circuit to be switchably selected during the display mode.

16. The display of claim 14, further comprising:

a touch controller configured to send the second voltage to the circuit to be switchably selected during the touch mode.

17. The display of claim 14, wherein the circuit is distant from the at least one display pixel so as to reduce interference with the at least one display pixel by inputs to the circuit.

18. The display of claim 14, further comprising:

a feedback controller configured to sense the second voltage on the gate line and to adjust the second voltage transmitted to the gate line based on the sensed voltage in order to reduce interference from the gate line on the display during the touch mode.

19. The display of claim 14, wherein the circuit comprises at least another switch configured to switch a node of the circuit to hold a logic state during the touch mode and to allow the node to update the logic state during the display mode.

20. The display of claim 14, further comprising:

a clock controller configured to disable a clock signal during the touch mode and to enable the clock signal during the display mode.

21. A system comprising:

a first drive region comprising a first plurality of display pixels;

a second drive region comprising a second plurality of display pixels;

a sense region disposed between the first and second drive regions and comprising a third plurality of display pixels;

conductive lines electrically connecting together at least some of the display pixels of the first and second drive regions along first and second directions and electrically bypassing the third plurality of display pixels in the sense region;

each display pixel having a gate, wherein a plurality of display pixels have their gates connected to a gate line; and

multiple voltage supplies;

an active area connectible to the voltage supplies and configured to operate during a display mode and a touch mode, the active area comprising at least the first and second drive regions and the sense region; and

a circuit configured to connect the active area to at least one of the voltage supplies to supply a first voltage to the active area during the display mode and to connect the active area to at least another of the voltage supplies to supply a second voltage to the active area during the touch mode.

22. The system of claim 21, wherein the at least one voltage supply is a display driver configured to drive the active area to display an image and the at least another voltage supply is a touch controller configured to drive the active area to sense a touch and to control which of the voltage supplies the circuit connects the active area to.

23. The system of claim 21, wherein the at least another voltage supply is an active ground that splits a ground voltage to individually supply each row of the active area during the touch mode.

24. The system of claim 21, wherein the voltage supplies, the active area, and the circuit are integrally formed on a chip.

25. A touch sensitive display comprising:

a first drive region comprising a first plurality of display pixels;

a second drive region comprising a second plurality of display pixels;

a sense region disposed between the first and second drive regions and comprising a third plurality of display pixels;

conductive lines electrically connecting together at least some of the display pixels of the first and second drive regions along first and second directions and electrically bypassing the third plurality of display pixels in the sense region;

each display pixel having a gate, wherein a plurality of display pixels have their gates connected to a gate line; and

at least one switch configured to transmit a voltage from a selected voltage supply to the gate line during a touch mode and to become inactive during a display mode.