In-cell touch display device

Patent metadata

Field	Value
Publication number	US-9335852-B2
Application number	US-201514863193-A
Country	US
Kind code	B2
Filing date	Sep 23, 2015
Priority date	Jul 16, 2014
Publication date	May 10, 2016
Grant date	May 10, 2016

Abstract

An in-cell touch display device. A panel has a plurality of data lines, a plurality of gate lines and a plurality of touch electrodes disposed thereon. A touch driving signal is applied to the plurality of touch electrodes when a driving mode is a touch mode. A data driver drives the plurality of data lines. A gate driver drives the plurality of gate lines. The gate driver sequentially outputs a scanning signal for driving the plurality of gate lines to the plurality of gate lines when the driving mode is a display mode, and outputs a load-free driving signal corresponding to the touch driving signal to at least one gate line when the driving mode is the touch mode. A level shifter generates the load-free driving signal. A multiplexer inputs a scanning voltage or the load-free driving signal to the gate driver depending on the driving mode.

First claim

What is claimed is:

1. A driver circuit for driving an in-cell touch display device, the in-cell touch display device comprising a panel including a plurality of data lines, a plurality of gate lines, and a plurality of touch electrodes disposed thereon, the driver circuit comprising:
a level shifter to modulate one of a high gate scanning voltage or a low gate scanning voltage based on a timing signal to generate a load-free gate driving signal having a same phase and a same amplitude as a touch driving signal; and
a selection circuit to select the high gate scanning voltage or the low gate scanning voltage responsive to a first state of a touch enable signal indicating a display period or to select the load-free gate driving signal responsive to a second state of the touch enable signal indicating a touch period,
wherein during the display period the high gate scanning voltage or the low gate scanning voltage is provided to one or more of the gate lines of the in-cell touch display device, and
wherein during the touch period the load-free gate driving signal is provided to one or more of the gate lines of the in-cell touch display device and the touch driving signal is provided to one or more of the touch electrodes.

2. The driver circuit of claim 1 , wherein the load-free gate driving signal is provided to all of the gate lines of the in-cell touch display device during the touch period.

3. The driver circuit of claim 1 , wherein the load-free gate driving signal is provided to one or more of the gate lines of the in-cell touch display device at a position corresponding to at least one or more of the touch electrodes to which the touch driving signal is applied during the touch period.

4. The driver circuit of claim 1 , wherein the level shifter generates the load-free gate driving signal to be identical to the touch driving signal.

5. The driver circuit of claim 1 , wherein the driver circuit further comprises a gate driver to drive the gate lines, the gate driver sequentially outputting either the high gate scanning voltage or the low gate scanning voltage to one or more of the gate lines during the display period, and outputting the load-free driving signal to one or more of the gate lines during the touch period.

6. The driver circuit of claim 1 , wherein the selection circuit is a multiplexer including a first input to receive either the high gate scanning voltage or the low gate scanning voltage, a second input to receive the load-free gate driving signal, either the first input or the second input being selected as an output responsive to the first state or the second state of the touch enable signal, respectively.

7. The driver circuit of claim 1 , further comprising a micro control unit to output the timing signal used for generation of the load-free gate driving signal to the level shifter.

8. The driver circuit of claim 7 , wherein the micro control unit receives the touch enable signal from a timing controller, and outputs the touch enable signal to the selection circuit.

9. The driver circuit of claim 1 , further comprising a power management integrated circuit to output the high gate scanning voltage or the low gate scanning voltage to the selection circuit.

10. The driver circuit of claim 1 , wherein the load-free gate driving signal is a square wave.

11. A method of driving an in-cell touch display device, the in-cell touch display device comprising a panel including a plurality of data lines, a plurality of gate lines, and a plurality of touch electrodes disposed thereon, the method comprising:
modulating one of a high gate scanning voltage or a low gate scanning voltage based on a timing signal to generate a load-free gate driving signal having a same phase and a same amplitude as a touch driving signal; and
selecting the high gate scanning voltage or the low gate scanning voltage responsive to a first state of a touch enable signal indicating a display period or selecting the load-free gate driving signal responsive to a second state of a touch enable signal indicating a touch period,
wherein during the display period the high gate scanning voltage or the low gate scanning voltage is provided to one or more of the gate lines of the in-cell touch display device, and
wherein during the touch period the load-free gate driving signal is provided to one or more of the gate lines of the in-cell touch display device and the touch driving signal is provided to one or more of the touch electrodes.

12. The method of claim 11 , wherein the load-free gate driving signal is provided to all of the gate lines of the in-cell touch display device during the touch period.

13. The method of claim 11 , wherein the load-free gate driving signal is provided to one or more of the gate lines of the in-cell touch display device at a position corresponding to at least one or more of the touch electrodes to which the touch driving signal is applied during the touch period.

14. The method of claim 11 , wherein the load-free gate driving signal is identical to the touch driving signal.

15. The method claim 11 , further comprising sequentially outputting either the high gate scanning voltage or the low gate scanning voltage to one or more of the gate lines during the display period, and outputting the load-free driving signal to one or more of the gate lines during the touch period.

16. The method of claim 11 , wherein the load-free gate driving signal is a square wave.

17. An in-cell touch display device comprising:
a panel including a plurality of data lines, a plurality of gate lines, and a plurality of touch electrodes disposed thereon, a touch driving signal being applied to the plurality of touch electrodes during a touch period;
a level shifter to modulate one of a high gate scanning voltage or a low gate scanning voltage based on a timing signal to generate a load-free gate driving signal having a same phase and a same amplitude as the touch driving signal;
a selection circuit to select the high gate scanning voltage or the low gate scanning voltage responsive to a first state of a touch enable signal indicating a display period or to select the load-free gate driving signal responsive to a second state of a touch enable signal indicating the touch period;
a data driver to drive the plurality of data lines; and
a gate driver to drive the gate lines, the gate driver sequentially outputting either the high gate scanning voltage or the low gate scanning voltage to one or more of the gate lines during the display period, and outputting the load-free gate driving signal to one or more of the gate lines during the touch period.

18. The in-cell touch display device of claim 17 , wherein the load-free gate driving signal is provided to all of the gate lines of the in-cell touch display device during the touch period.

19. The in-cell touch display device of claim 17 , wherein the load-free gate driving signal is provided to one or more of the gate lines of the in-cell touch display device at a position corresponding to at least one or more of the touch electrodes to which the touch driving signal is applied during the touch period.

20. The in-cell touch display device of claim 17 , wherein the level shifter generates the load-free gate driving signal to be identical to the touch driving signal.

21. The in-cell touch display device of claim 17 , wherein the selection circuit is a multiplexer including a first input to receive either the high gate scanning voltage or the low gate scanning voltage, a second

Assignees

• Lg Display Co Ltd

Inventors

• Lee Kijeong
• Kwon Keuksang
• Park Seungchul

Classifications

• G06F3/0412

  Digitisers structurally integrated in a display · CPC title

• G09G5/00

  Control arrangements or circuits for visual indicators common to cathode-ray tube indicators and other visual indicators (image data processing or generation, in general G06T) · CPC title

• G06F3/041 Primary

  Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means · CPC title

• G06F3/044 Primary

  by capacitive means · CPC title

• G09G2310/08

  Details of timing specific for flat panels, other than clock recovery · CPC title