SWITCHING CIRCUITRY FOR TOUCH SENSITIVE DISPLAY

• US 20150077375A1
• Filed: 11/21/2014
• Published: 03/19/2015
• Est. Priority Date: 02/02/2009
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: HOTELLING, Steven P., YOUSEFPOR, Marduke, CHANG, Shih Chang
• Granted Patent: US 9,996,175 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 1/3218 of display devices
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04164 Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads
• 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 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: G09G 2300/0809 Several active elements per pixel in active matrix panels
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: G09G 3/3666 with the matrix divided into sections

Abstract

A circuit for switching an LCD between display and touch modes is disclosed. The circuit can include one or more switches configured to switch one or more drive, sense, and data lines in LCD pixels according to the mode. During touch mode, the circuit switches can be configured to switch one or more drive lines to receive stimulation signals, one or more sense lines to transmit touch signals, and one or more data lines to transmit residual data signals. During display mode, the circuit switches can be configured to switch one or more drive lines and sense lines to receive common voltage signals and one or more data lines to receive data signals. The circuit can be formed around the border of the LCD chip or partially or fully on a separate chip.

Claims

1. An integrated touch screen comprising:

a plurality of pixels configured to;

display data on the touch screen during a display mode of the touch screen, and

sense one or more touch events on the touch screen during a touch mode of the touch screen;

a plurality of touch regions, each touch region including at least one of the plurality of pixels, and each touch region configured to sense a touch event at a respective location on the touch screen during the touch mode; and

circuitry configured to;

couple one or more of the touch regions to touch circuitry during the touch mode, and

couple the one or more of the touch regions to a common voltage source during the display mode.

2. The integrated touch screen of claim 1, wherein the touch regions are coupled to the touch circuitry during the touch mode with one or more conductive traces.

3. The integrated touch screen of claim 1, wherein the touch regions are coupled to the common voltage source during the display mode with one or more conductive traces.

4. The integrated touch screen of claim 3, wherein the common voltage source is configured to apply a common voltage to the one or more of the touch regions during the display mode using the one or more conductive traces.

5. The integrated touch screen of claim 1, wherein each touch region includes a touch electrode.

6. The integrated touch screen of claim 1, wherein the circuitry comprises one or more switches configured to:

couple the one or more of the touch regions to the touch circuitry during the touch mode, and

couple the one or more of the touch regions to the common voltage source during the display mode.

7. The integrated touch screen of claim 6, wherein the circuitry comprises a controller configured to control the one or more switches.

8. The integrated touch screen of claim 1, wherein the at least one of the plurality of pixels comprises a data line, and the circuitry is configured to couple the data line to receive a data signal during the display mode.

9. The integrated touch screen of claim 8, wherein the circuitry is further configured to couple the data line to receive a common voltage during the touch mode.

10. The integrated touch screen of claim 1, incorporated into at least one of a mobile telephone, a digital media player, and a personal computer.

11. A method comprising:

coupling one or more touch regions to touch circuitry during a touch mode of a touch screen; and

coupling the one or more of the touch regions to a common voltage source during a display mode of the touch screen,

wherein the touch screen comprises;

a plurality of pixels configured to;

display data on the touch screen during the display mode of the touch screen, and

sense one or more touch events on the touch screen during the touch mode of the touch screen, and

a plurality of touch regions including the one or more of the touch regions, each touch region including at least one pixel, and each touch region configured to sense a touch event at a respective location on the touch screen during the touch mode.

12. The method of claim 11, wherein the touch regions are coupled to the touch circuitry during the touch mode with one or more conductive traces.

13. The method of claim 11, wherein the touch regions are coupled to the common voltage source during the display mode with one or more conductive traces.

14. The method of claim 11, wherein the common voltage source is configured to apply a common voltage to the one or more of the touch regions during the display mode using the one or more conductive traces.

15. The method of claim 11, wherein the circuitry comprises one or more switches configured to:

couple the one or more of the touch regions to the touch circuitry during the touch mode, and

couple the one or more of the touch regions to the common voltage source during the display mode.

16. The method of claim 15, wherein the circuitry comprises a controller configured to control the one or more switches.

17. The method of claim 11, wherein at least one of the plurality of pixels comprises a data line, and the circuitry is configured to couple the data line to receive a data signal during the display mode.

18. The method of claim 17, wherein the circuitry is further configured to couple the data line to receive a common voltage during the touch mode.

19. The method of claim 11, wherein the touch screen is incorporated into at least one of a mobile telephone, a digital media player, and a personal computer.

20. A non-transitory computer readable storage medium storing one or more programs, the one or more programs comprising instructions, which when executed by a device, cause the device to perform a method comprising:

coupling one or more touch regions to touch circuitry during a touch mode of a touch screen; and

coupling the one or more of the touch regions to a common voltage source during a display mode of the touch screen,

wherein the touch screen comprises;

a plurality of pixels configured to;

display data on the touch screen during the display mode of the touch screen, and

sense one or more touch events on the touch screen during the touch mode of the touch screen, and

a plurality of touch regions including the one or more touch regions, each touch region including at least one of the plurality of pixels, and each touch region configured to sense a touch event at a respective location on the touch screen during the touch mode.