Display device with an integrated touch screen and method for driving the same

• US 9,075,463 B2
• Filed: 12/13/2012
• Issued: 07/07/2015
• Est. Priority Date: 06/20/2012
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Pyo, SeungEun, Kim, HongChul
• Primary Examiner(s): Sharifi-Tafreshi, Koosha
• Application Number:
  US13/714,053
• Publication Number:
  US 20130342479A1
• Time in Patent Office: 936 Days
• Field of Search: 345/103, 345/104, 345/173, 345/174
• US Class Current: 1/1
• 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 3/04166 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 3/044 by capacitive means
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes

Abstract

A display device with an integrated touch screen including a panel including electrodes divided into n number of groups, where n is an integer more than or equal to two; a display driver IC configured to apply a common voltage to the n divided groups when a driving mode of the panel is a display driving mode, and to selectively apply a touch scan signal or the common voltage to the n divided groups when the driving mode of the panel is a touch driving mode; and a touch IC configured to generate the touch scan signal to apply the touch scan signal to the display driver IC.

Claims

1. A display device with an integrated touch screen, comprising:

a panel including electrodes divided into n number of groups, wherein n is an integer more than or equal to two;

a display driver IC configured to;

apply a common voltage of a first level to the n divided groups, when a driving mode of the panel is a display driving mode, and

sequentially select at least one of the n divided groups and apply a touch scan signal to the at least one selected group, while applying the common voltage of the first level to unselected n divided groups, when the driving mode of the panel is a touch driving mode; and

a touch IC configured to generate the touch scan signal to apply the touch scan signal to the display driver IC,

wherein the display driver IC includes a switching unit configured to apply the touch scan signal from the touch IC to the at least one selected group, while applying the common voltage of the first level to the unselected n divided groups, during the touch driving mode.

2. The display device of claim 1, wherein when the driving mode is the touch driving mode, the display driver IC is further configured to apply the common voltage of the first level to a group to which the touch scan signal is not applied.

3. The display device of claim 1, wherein the display driver IC comprises:

a common voltage generation unit configured to generate the common voltage of the first level;

and

a control unit configured to generate a sync signal that indicates the driving mode of the panel, and a control signal configured to control the switching unit to connect each of the n divided groups with either the common voltage generation unit or the touch IC.

4. The display device of claim 3, wherein the control unit comprises:

a sync controller configured to generate the sync signal; and

a switching controller configured to generate the control signal.

5. The display device of claim 4, wherein the switching controller is configured to generate the control signal according to the sync signal.

6. The display device of claim 1, wherein the common voltage of the first level applied during the display driving mode and the touch driving mode is not a ground voltage.

7. The display device of claim 1, wherein the touch scan signal includes a voltage signal of a second level.

8. The display device of claim 7, wherein the first level is lower than the second level.

9. A method of controlling a display device with an integrated touch screen, a panel of the display device including electrodes divided into n number of groups, wherein n is an integer more than or equal to two, the method comprising:

applying, via a display driver IC of the display device, a common voltage of a first level to the n divided groups, when a driving mode of the panel is a display driving mode;

sequentially selecting at least one of the n divided groups and applying, via the display driver IC, a touch scan signal to the at least one selected group, while applying the common voltage of the first level to unselected n divided groups, when the driving mode of the panel is a touch driving mode; and

generating, via a touch IC of the display device, the touch scan signal to apply the touch scan signal to the display driver IC,

wherein the touch scan signal is applied from the touch IC, via a switching unit included in the display driver IC, to the at least one selected group, while the common voltage of the first level is applied, via the switching unit, to the unselected n divided groups, during the touch driving mode.

10. The method of claim 9, wherein when the driving mode is the touch driving mode, the sequentially selecting comprises applying the common voltage of the first level to a group to which the touch scan signal is not applied.

11. The method of claim 9, wherein the display driver IC comprises:

a common voltage generation unit configured to generate the common voltage of the first level;

and

a control unit configured to generate a sync signal that indicates the driving mode of the panel, and a control signal configured to control the switching unit to connect each of the n divided groups with the common voltage generation unit or the touch IC respectively.

12. The method of claim 11, wherein the control unit comprises:

a sync controller configured to generate the sync signal; and

a switching controller configured to generate the control signal.

13. The method of claim 12, wherein the switching controller generates the control signal according to the sync signal.

14. The method of claim 9, wherein the common voltage of the first level applied during the display driving mode and the touch driving mode is not a ground voltage.

15. The method of claim 9, wherein the touch scan signal includes a voltage signal of a second level.

16. The method of claim 15, wherein the first level is lower than the second level.