Display device having in-cell touch structure and method of driving the same

• US 9,690,437 B2
• Filed: 08/26/2015
• Issued: 06/27/2017
• Est. Priority Date: 08/26/2015
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Shin, SeungRok, Jung, JiHyun, Lee, DeukSu, Kim, Taeyun
• Primary Examiner(s): Sitta, Grant
• Application Number:
  US14/836,762
• Publication Number:
  US 20170060289A1
• Time in Patent Office: 671 Days
• Field of Search: 345156-175
• 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 2300/0426 Layout of electrodes and connections
• CPC Class Codes: G09G 2354/00 Aspects of interface with display user
• CPC Class Codes: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
• CPC Class Codes: G09G 5/003 Details of a display terminal, the details relating to the control arrangement of the display terminal and to the interfaces thereto specific for a CRT G09G1/165; for a flat panel G09G3/2092

Abstract

A display driver circuit comprises first circuitry to generate a touch drive signal, and second circuitry to provide the touch drive signal to touch sense electrodes of the display device and a touch data signal to data lines of the display device during a touch period and to provide display data signals to data lines of the display device during a display period. A touch gate signal is provided to gate lines of the display device during the touch period. The touch drive signal, the touch data signal, and the touch gate signal mimic a reference waveform, but amplitudes of one or more of the touch drive signal, the touch data signal, and the touch gate signal are overdriven by their respective overdrive amplitude with respect to the reference waveform during their respective overdrive duration.

Claims

1. A display driver circuit for driving a display device, the display driver circuit comprising:

first circuitry to generate a touch drive signal; and

second circuitry to provide the touch drive signal to touch sense electrodes of the display device and a touch data signal to data lines of the display device during a touch period and to provide display data signals to the data lines of the display device during a display period,

wherein a touch gate signal is provided to gate lines of the display device during the touch period, and

wherein the touch drive signal, the touch data signal, and the touch gate signal are driven in phase with each other and amplitudes of (a) the touch drive signal and (b) one or more of the touch data signal and the touch gate signal are overdriven by their respective overdrive amplitude with respect to a reference waveform during their respective overdrive duration.

2. The display driver circuit of claim 1, wherein one or more of the overdrive amplitudes or the overdrive durations of the touch data signal or the touch gate signal is different from the overdrive amplitude or overdrive duration of the touch drive signal.

3. The display driver circuit of claim 1, wherein:

the reference waveform is a pulse waveform periodically alternating between a high level and a low level, and

one or more of the touch driving signal, the touch data signal, and the touch gate signal have two or more different high voltage levels during the high level and two or more different low voltage levels during the low level.

4. The display driver circuit of claim 1, wherein the overdrive amplitude or the overdrive duration is greater as distance from the second circuitry to the touch sense electrodes, the data lines, or the gate lines is farther.

5. The display driver circuit of claim 1, wherein the overdrive durations begin when the touch drive signal, the touch data signal, or the touch gate signal transitions from low level to high level, or vice versa.

6. The display driver circuit of claim 1, wherein amplitudes of two or more of the touch drive signal, the touch data signal, and the touch gate signal are same at transition from low level to high level, or vice versa, said transition occurring subsequent to end of the overdrive duration, regardless of position in the data lines or the gate lines or of the touch sense electrodes.

7. A method for driving a display device, the method comprising:

generating a touch drive signal; and

providing the touch drive signal to touch sense electrodes of the display device and a touch data signal to data lines of the display device during a touch period and to provide display data signals to the data lines of the display device during a display period,

wherein a touch gate signal is provided to gate lines of the display device during the touch period, and

wherein the touch drive signal, the touch data signal, and the touch gate signal are driven in phase with each other and amplitudes of (a) the touch drive signal and (b) one or more of the touch data signal and the touch gate signal are overdriven by their respective overdrive amplitude with respect to a reference waveform during their respective overdrive duration.

8. The method of claim 7, wherein one or more of the overdrive amplitudes or the overdrive durations of the touch data signal or the touch gate signal is different from the overdrive amplitude or overdrive duration of the touch drive signal.

9. The method of claim 7, wherein:

the reference waveform is a pulse waveform periodically alternating between a high level and a low level, and

one or more of the touch driving signal, the touch data signal, and the touch gate signal have two or more different high voltage levels during the high level and two or more different low voltage levels during the low level.

10. The method of claim 7, wherein the overdrive amplitude or the overdrive duration is greater as distance from the second circuitry to the touch sense electrodes, the data lines, or the gate lines is farther.

11. The method of claim 7, wherein the overdrive durations begin when the touch drive signal, the touch data signal, or the touch gate signal transitions from low level to high level, or vice versa.

12. The method of claim 7, wherein amplitudes of two or more of the touch drive signal, the touch data signal, and the touch gate signal are same at transition from low level to high level, or vice versa, said transition occurring subsequent to end of the overdrive duration, regardless of position in the data lines or the gate lines or of the touch sense electrodes.

13. A display device comprising:

a panel including a plurality of data lines, a plurality of gate lines, and a plurality of electrodes grouped into a plurality of electrode groups, pixels of the display device being defined at intersections of the gate lines and the data lines;

a touch driver to provide a touch drive signal to the electrodes of the display device during a touch period;

a data driver to provide display data signals to the data lines of the display device during a display period and a touch data signal to the data lines of the display device during the touch period; and

a gate driver sequentially supplying a scanning signal to the gate lines during the display period and to provide a touch gate signal to the gate lines during the touch period,

wherein the touch drive signal, the touch data signal, and the touch gate signal are driven in phase with each other and amplitudes of (a) the touch drive signal and (b) one or more of the touch data signal and the touch gate signal are overdriven by their respective overdrive amplitude with respect to a reference waveform during their respective overdrive duration.

14. The display device of claim 13, wherein one or more of the overdrive amplitudes or the overdrive durations of the touch data signal or the touch gate signal is different from the overdrive amplitude or overdrive duration of the touch drive signal.

15. The display device of claim 13, wherein:

the reference waveform is a pulse waveform periodically alternating between a high level and a low level, and

one or more of the touch driving signal, the touch data signal, and the touch gate signal have two or more different high voltage levels during the high level and two or more different low voltage levels during the low level.

16. The display device of claim 13, wherein the overdrive amplitude or the overdrive duration is greater as distance from the second circuitry to the touch sense electrodes, the data lines, or the gate lines is farther.

17. The display device of claim 13, wherein the overdrive durations begin when the touch drive signal, the touch data signal, or the touch gate signal transitions from low level to high level, or vice versa.

18. The display device of claim 13, wherein amplitudes of two or more of the touch drive signal, the touch data signal, and the touch gate signal are same at transition from low level to high level, or vice versa, said transition occurring subsequent to end of the overdrive duration, regardless of position in the data lines or the gate lines or of the touch sense electrodes.