SWITCHING CIRCUITRY FOR TOUCH SENSITIVE DISPLAY

• US 20100194698A1
• Filed: 08/21/2009
• Published: 08/05/2010
• Est. Priority Date: 02/02/2009
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: HOTELLING, Steven Porter, Yousefpor, Marduke, Chang, Shih Chang
• Granted Patent: US 8,922,521 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. A circuit for switching an integrated touch screen between different modes, comprising:

a switch configured to switch at least one of a drive line, a sense line, or a data line between a first configuration associated with a display mode and a second configuration associated with a touch mode.

2. The circuit of claim 1, wherein the first configuration comprises the drive line being switched to receive a common voltage signal.

3. The circuit of claim 1, wherein the first configuration comprises the data line being switched to receive a data signal.

4. The circuit of claim 1, wherein the first configuration comprises the sense line being switched to receive a common voltage signal.

5. The circuit of claim 1, wherein the second configuration comprises the drive line being switched to receive a stimulation signal.

6. The circuit of claim 1, wherein the second configuration comprises the data line being switched either to receive a common voltage signal or to transmit a residual data signal to a touch circuit.

7. The circuit of claim 1, wherein the second configuration comprises the sense line being switched either to receive a common voltage signal or to transmit a touch signal to a touch circuit.

8. The circuit of claim 1, comprising:

a controller configured to control the switch.

9. The circuit of claim 1 incorporated into an integrated touch screen.

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

11. A touch sensitive display switchable between different modes, the device comprising:

a display pixel having a drive line, a sense line, and a data line; and

a circuit having a switch configured to switch at least one of the drive line, the sense line, or the data line between a display mode and a touch mode.

12. The touch sensitive display of claim 11, comprising:

a drive region comprising the display pixel,

wherein the circuit comprises the switch configured to switch the drive line of the display pixel to receive a stimulation signal during the touch mode and to receive a common voltage signal during the display mode.

13. The touch sensitive display of claim 11, comprising:

a drive region comprising the display pixel,

wherein the circuit comprises the switch configured to switch the data line of the display pixel to receive a common voltage signal during the touch mode and to receive a data signal during the display mode.

14. The touch sensitive display of claim 11, comprising:

a ground region comprising the display pixel,

wherein the circuit comprises the switch configured to switch the data line of the display pixel to receive a common voltage signal during the touch mode and to receive a data signal during the display mode.

15. The touch sensitive display of claim 11, comprising:

a sense region comprising the display pixel,

wherein the circuit comprises the switch configured, during the touch mode, to switch the sense line of the display pixel to transmit a touch signal to a touch circuit and the data line of the display pixel to couple with the sense line and, during the display mode, to switch the sense line to receive a common voltage signal and the data line to receive a data signal.

16. The touch sensitive display of claim 11, comprising:

a touch circuit configured to receive a touch signal from the sense line and to send a stimulation signal to the drive line during the touch mode.

17. The touch sensitive display of claim 11, comprising:

a display circuit configured to send a data signal to the data line during the display mode.

18. A method for switching between different modes in a touch sensitive display, comprising:

providing a plurality of pixels in a touch sensitive display having a display mode and a touch mode; and

switching at least one of a drive line, a sense line, or a data line in each of the plurality of pixels between the display mode and the touch mode.

19. The method of claim 18, wherein the switching comprises:

for the touch mode, at least one of switching the sense line to connect to a touch circuit for sensing a touch or near touch, switching the drive line to connect to a touch circuit for driving a stimulation signal, or switching the data line to connect to a common voltage source.

20. The method of claim 18, wherein the switching comprises:

for the display mode, at least one of switching the sense line to connect to a common voltage source, switching the drive line to connect to a common voltage source, or switching the data line to connect to a display circuit for displaying graphics or data.

21. A method for forming a circuit for switching between different modes in a touch sensitive display, comprising:

forming a switch configured to switch at least one of a drive line, a sense line, or a data line between a display mode and a touch mode in a touch sensitive display, wherein the switch is formed on a surface having at least one of the drive line, the sense line, or the data line.

22. The method of claim 21, wherein the switch is formed around a border of the surface.

23. The method of claim 21, comprising:

forming a connection between the switch and at least one of the drive line, the sense line, or the data line, wherein the connection is formed on the surface.

24. The method of claim 23, wherein the connection is formed around a border of the surface.

25. An integrated touch screen switchable between different modes, comprising:

a plurality of pixels having different modes including a touch mode and a display mode; and

a circuit comprising at least one switch configured to switch at least one of a drive line, a sense line, or a data line in each of the plurality of pixels between the different modes.