Driving chip, circuit film, chip-on-film type driving circuit, and display device having built-in touchscreen

• US 9,971,451 B2
• Filed: 10/10/2017
• Issued: 05/15/2018
• Est. Priority Date: 08/31/2016
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Kim, KiYong, Jo, Youngwoo
• Primary Examiner(s): Sadio, Insa
• Application Number:
  US15/729,474
• Publication Number:
  US 20180059861A1
• Time in Patent Office: 217 Days
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G06F 2203/04107 Shielding in digitiser, i.e. guard or shielding arrangements, mostly for capacitive touchscreens, e.g. driven shields, driven grounds
• 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 3/0418 for error correction or compensation, e.g. based on parallax, calibration or alignment
• 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 having a built-in touchscreen and a driving chip, a circuit film, and a chip-on-film (COF) type driving circuit included in the display device. The COF type driving circuit performs data driving and touch driving in a combined manner. A source driving circuit outputs image data voltages through data channels. At least one touch driving circuit outputs touch driving signals through touch channels. The source driving circuit and the at least one touch driving circuit are mounted on an integrated circuit film. Data channel lines electrically connected to the data channels and touch channel lines electrically connected to the touch channels are disposed on the integrated circuit film. The noise avoidance line disposed on the integrated circuit film is located outward of an at least one outermost touch channel line.

Claims

1. A chip-on-film type driving circuit for performing data driving and touch driving in a touch enabled display panel, the chip-on-film type driving circuit connected to the touch enabled display panel and comprising:

a source driving circuit to output image data voltages through a plurality of data channels in a display mode;

a touch driving circuit to output touch driving signals through a plurality of touch channels in a touch mode; and

an integrated circuit film on which the source driving circuit and the touch driving circuit are mounted;

a plurality of data channel lines each electrically connected to a corresponding one of the data channels of the source driving circuit;

a plurality of touch channel lines each electrically connected to a corresponding one of the touch channels of the touch driving circuit to carry a touch drive signal during the touch mode; and

a conductive line adjacent to the plurality of touch channel lines, a touch sense signal not being sensed from the conductive line in the touch mode and the conductive line not carrying the image data voltages in the display mode.

2. The chip-on-film type driving circuit of claim 1, wherein the conductive line is disposed between the touch channel lines and the data channel lines.

3. The chip-on-film type driving circuit of claim 1, wherein the conductive line has a shape following a shape of one of the touch channel lines to which the conductive line is adjacent.

4. The chip-on-film type driving circuit of claim 1, wherein during the display mode, a common voltage is applied to the conductive line.

5. The chip-on-film type driving circuit according to claim 1, wherein a noise avoidance signal corresponding to the touch driving signal is applied to the conductive line in response to the touch driving signal being applied to one of the touch channel lines to which the conductive line is adjacent, the noise avoidance signal being identical to, or in phase with, the touch driving signal.

6. The chip-on-film type driving circuit according to claim 1, wherein a noise avoidance signal corresponding to the touch driving signal is applied to the conductive line in response to the touch driving signal being applied to one of the touch channel lines to which the conductive line is adjacent, an amplitude of the noise avoidance signal being identical to an amplitude of the touch driving signal.

7. The chip-on-film type driving circuit according to claim 1, wherein a noise avoidance signal corresponding to the touch driving signal is applied to the conductive line in response to the touch driving signal being applied to one of the touch channel lines to which the conductive line is adjacent, an amplitude of the noise avoidance signal being greater than an amplitude of the touch driving signal.

8. The chip-on-film type driving circuit according to claim 1, wherein the touch channel lines are electrically connected to a display panel, and the conductive line is not electrically connected to the display panel.

9. The chip-on-film type driving circuit according to claim 1, wherein the touch channel lines comprises:

a first outermost touch channel line located outermost from the source driving circuit;

a second outermost touch channel line located closest to the source driving circuit,

wherein the first outermost touch channel line is longer than the second outermost touch channel line.

10. The chip-on-film type driving circuit according to claim 9, wherein the conductive line is located adjacent to the first outermost touch channel line.

11. The chip-on-film type driving circuit according to claim 9, wherein the conductive line includes a first conductive line and a second conductive line, the first conductive line being adjacent to the first outermost touch channel line, and the second conductive line being adjacent to the second outermost touch channel line.

12. The chip-on-film type driving circuit according to claim 1, wherein the touch driving circuit includes two touch driving circuits, the source driving circuit is mounted on a central portion of the integrated circuit film, a first one of the two touch driving circuits is mounted on the integrated circuit film on a first side of the source driving circuit, and a second one of the two touch driving circuits is mounted on the integrated circuit film on a second side of the source driving circuit.

13. The chip-on-film type driving circuit according to claim 1, wherein the touch channel lines on the integrated circuit film include a first group of touch channel lines connected to one side of the touch driving circuit and a second group of touch channel lines connected to another side of the touch driving circuit opposite said one side of the touch driving circuit.

14. The chip-on-film type driving circuit according to claim 13,

wherein the integrated circuit film comprises a bonding area disposed on one end and electrically connected to the touch enabled display panel,

wherein each of the touch channel lines belonging to the first group of touch channel lines has one end connected to one side of the touch driving circuit and another end connected to the bonding area, and

wherein each of the touch channel lines belonging to the second group of touch channel lines has one end connected to said another side of the touch driving circuit, an intermediate portion located adjacent to a side of the touch driving circuit, and another end connected to the bonding area.

15. The chip-on-film type driving circuit according to claim 14, further comprising another conductive line disposed between the first group of touch channel lines and the second group of touch channel lines.

16. The chip-on-film type driving circuit according to claim 1, wherein the touch driving circuit comprises:

an outermost touch pad connected to one of the touch channel lines to which the conductive line is adjacent;

a conductive line pad located adjacent to the outermost touch pad and connected to the conductive line; and

a connecting line electrically connecting the outermost touch pad and the conductive line pad.

17. The chip-on-film type driving circuit according to claim 1, further comprising a connecting line disposed on the integrated circuit film, the connecting line electrically connecting one of the touch channel lines to which the conductive line is adjacent and the conductive line.

18. The chip-on-film type driving circuit according to claim 1, wherein the touch driving circuit comprises:

an outermost touch pad connected to one of the touch channel lines to which the conductive line is adjacent;

a conductive line pad located adjacent to the outermost touch pad and connected to the conductive line;

a touch driving signal output circuit outputting the touch driving signal through the outermost touch pad; and

a noise avoidance signal output circuit outputting a noise avoidance signal through the conductive line pad.

19. The chip-on-film type driving circuit according to claim 1, wherein a first distance between one of the touch channel lines to which the conductive line is adjacent and the conductive line is different from a second distance between two adjacent touch channel lines among the touch channel lines.

20. The chip-on-film type driving circuit according to claim 19, wherein the first distance is shorter than the second distance.

21. The chip-on-film type driving circuit according to claim 1, wherein a first thickness of the conductive line is different from a second thickness of the touch channel line.

22. The chip-on-film type driving circuit according to claim 21, wherein the first thickness of the conductive line is greater than the second thickness of the touch channel line.

23. A display device, comprising:

a touch enabled display panel;

a chip-on-film type driving circuit connected to the touch enabled display panel and performing data driving and touch driving in the touch enabled display panel, the chip-on-film type driving circuit comprising;

a source driving circuit to output image data voltages through a plurality of data channels in a display mode;

a touch driving circuit to output touch driving signals through a plurality of touch channels in a touch mode; and

an integrated circuit film on which the source driving circuit and the touch driving circuit are mounted;

a plurality of data channel lines each electrically connected to a corresponding one of the data channels of the source driving circuit;

a plurality of touch channel lines each electrically connected to a corresponding one of the touch channels of the touch driving circuit to carry a touch drive signal during the touch mode; and

a conductive line adjacent to the plurality of touch channel lines, a touch sense signal not being sensed from the conductive line in the touch mode and the conductive line not carrying the image data voltages in the display mode.

24. The display device according to claim 23, wherein the conductive line is disposed between the touch channel lines and the data channel lines.

25. The display device according to claim 23, wherein the conductive line has a shape following a shape of one of the touch channel lines to which the conductive line is adjacent.

26. The display device according to claim 23, wherein during the display mode, a common voltage is applied to the conductive line.

27. The display device according to claim 23, wherein a noise avoidance signal corresponding to the touch driving signal is applied to the conductive line in response to the touch driving signal being applied to one of the touch channel lines to which the conductive line is adjacent, the noise avoidance signal being identical to, or in phase with, the touch driving signal.

28. The display device according to claim 23, wherein a noise avoidance signal corresponding to the touch driving signal is applied to the conductive line in response to the touch driving signal being applied to one of the touch channel lines to which the conductive line is adjacent, an amplitude of the noise avoidance signal being identical to an amplitude of the touch driving signal.

29. The display device according to claim 23, wherein a noise avoidance signal corresponding to the touch driving signal is applied to the conductive line in response to the touch driving signal being applied to one of the touch channel lines to which the conductive line is adjacent, an amplitude of the noise avoidance signal being greater than an amplitude of the touch driving signal.

30. The display device according to claim 23, wherein the touch channel lines are electrically connected to a display panel, and the conductive line is not electrically connected to the display panel.

31. The display device according to claim 23, further comprising a connecting line disposed on the integrated circuit film, the connecting line electrically connecting one of the touch channel lines to which the conductive line is adjacent and the conductive line.

32. The display device according to claim 23, wherein a first distance between one of the touch channel lines to which the conductive line is adjacent and the conductive line is shorter than a second distance between two adjacent touch channel lines among the touch channel lines.

33. The display device according to claim 23, wherein a first thickness of the conductive line is greater than a second thickness of the touch channel line.