U.S. patent application number 14/957574 was filed with the patent office on 2017-04-13 for touch circuit, touch display driver circuit, touch display device, and method of driving the same.
The applicant listed for this patent is LG Display Co., Ltd.. Invention is credited to Seongkyu KANG, SungChul KIM.
Application Number | 20170102824 14/957574 |
Document ID | / |
Family ID | 55023959 |
Filed Date | 2017-04-13 |
United States Patent
Application |
20170102824 |
Kind Code |
A1 |
KANG; Seongkyu ; et
al. |
April 13, 2017 |
TOUCH CIRCUIT, TOUCH DISPLAY DRIVER CIRCUIT, TOUCH DISPLAY DEVICE,
AND METHOD OF DRIVING THE SAME
Abstract
A touch circuit, a display driver circuit, a touch display
device, and a method of driving the same. After display driving is
ended and before touch driving begins to be performed, touch
driving and touch sensing are accurately performed through
pre-setting driving without the influence of display driving that
was ended already. An accurate touch sensing result without touch
sensing noise is obtained.
Inventors: |
KANG; Seongkyu; (Paju-si,
KR) ; KIM; SungChul; (Goyang-si, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LG Display Co., Ltd. |
Seoul |
|
KR |
|
|
Family ID: |
55023959 |
Appl. No.: |
14/957574 |
Filed: |
December 2, 2015 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G09G 2310/0297 20130101;
G06F 3/04166 20190501; G06F 3/044 20130101; G09G 5/006 20130101;
G09G 2300/0413 20130101; G06F 3/0418 20130101; G09G 2310/0245
20130101; G09G 2310/0275 20130101; G06F 3/04184 20190501; G06F
3/0443 20190501; G06F 3/0412 20130101; G06F 3/0416 20130101; G09G
2310/08 20130101 |
International
Class: |
G06F 3/041 20060101
G06F003/041; G06F 3/044 20060101 G06F003/044; G09G 5/00 20060101
G09G005/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 12, 2015 |
KR |
10-2015-0142035 |
Claims
1. A touch sensitive display device comprising: a display panel
including a plurality of electrodes; and circuitry to drive the
electrodes during at least a display mode and a touch mode,
wherein: during the display mode, the circuitry provides a common
voltage to the electrodes; during the touch mode, the circuitry
provides a touch driving signal to at least one first electrode of
the electrodes; and during a pre-setting period after the common
voltage is provided to the electrodes and before the touch driving
signal is provided to the at least one first electrode, the
circuitry provides a pre-setting dummy pulse signal to the at least
one first electrode, and the circuitry disregards touch sensing
data generated responsive to the pre-setting dummy pulse signal,
wherein the pre-setting dummy pulse signal has a same phase as the
touch driving signal.
2. The touch sensitive display device of claim 1, further
comprising: a timing controller to generate a synchronization
signal having a first state during the touch mode and a second
state during the display mode.
3. The touch sensitive display device of claim 2, wherein the
pre-setting period is during the touch mode when the
synchronization signal is in the first state.
4. The touch sensitive display device of claim 2, wherein the
pre-setting period is during the display mode when the
synchronization signal is in the second state.
5. The touch sensitive display device of claim 1, wherein during
the touch mode: the circuitry provides the touch driving signal to
at least one second electrode of the electrodes after providing the
touch driving signal to the at least one first electrode, and the
circuitry does not provide the pre-setting dummy pulse signal to
the at least one second electrode.
6. The touch sensitive display device of claim 1, wherein during
the touch mode, the circuitry: provides the pre-setting dummy pulse
signal to at least one second electrode of the electrodes after
providing the touch driving signal to the at least one first
electrode, and provides the touch driving signal to the at least
one second electrode after providing the pre-setting dummy pulse
signal to the at least one second electrode.
7. The touch sensitive display device of claim 1, wherein the
display panel comprises: a plurality of data lines; and a plurality
of gate lines, wherein the circuitry provides a pre-setting load
free driving (LFD) signal to at least one of the gate lines or data
lines while the pre-setting dummy pulse signal is provided to the
at least one first electrode, and wherein the pre-setting LFD
signal has a same phase as the pre-setting dummy pulse signal.
8. The touch sensitive display device of claim 1, wherein during
another display mode following the touch mode, the circuitry again
provides the common voltage to the electrodes, and during a
post-setting period after the circuitry provides the touch driving
signal to the at least one electrode and before the circuitry again
provides the common voltage to the electrodes, the circuitry
provides a post-setting signal to the electrodes that is same as
the common voltage.
9. (canceled)
10. The touch sensitive display device of claim 1, wherein the
pre-setting dummy pulse signal has a same amplitude as the touch
driving signal.
11. The touch sensitive display device of claim 1, wherein the
pre-setting dummy pulse signal has a greater amplitude than the
touch driving signal.
12. The touch sensitive display device of claim 1, wherein the
touch driving signal comprises one or more reset pulses and one or
more real touch driving pulses after the one or more reset pulses,
and wherein the circuitry does not sense touch from touch sensing
data generated responsive to the reset pulses and senses touch from
touch sensing data generated responsive to the one or more real
touch driving pulses.
13. A driver circuit for a touch sensitive display panel that
includes a plurality of electrodes, the driver circuit comprising:
circuitry to drive the electrodes during at least a display mode
and a touch mode, the circuitry to: during the display mode,
provide a common voltage to the electrodes; during the touch mode,
provide a touch driving signal to at least one first electrode of
the electrodes; and during a pre-setting period after the common
voltage is provided to the electrodes and before the touch driving
signal is provided to the at least one first electrode, provide a
pre-setting dummy pulse signal to the at least one first electrode,
wherein touch sensing data generated responsive to the pre-setting
dummy pulse signal is disregarded, and wherein the pre-setting
dummy pulse signal has a same phase as the touch driving
signal.
14. The driver circuit of claim 13, wherein the circuitry receives
a synchronization signal having a first state during the touch mode
and a second state during the display mode.
15. The driver circuit of claim 14, wherein the pre-setting period
is during the touch sensing mode when the synchronization signal is
in the first state.
16. The driver circuit of claim 14, wherein the pre-setting period
is during the display mode when the synchronization signal is in
the second state.
17. The driver circuit of claim 13, wherein during the touch
sensing mode: the circuitry provides the touch driving signal to at
least one second electrode of the electrodes after providing the
touch driving signal to the at least one first electrode, and the
circuitry does not provide the pre-setting dummy pulse signal to
the at least one second electrode.
18. The driver circuit of claim 13, wherein during the touch
sensing mode, the circuitry: provides the pre-setting dummy pulse
signal to at least one second electrode of the electrodes after
providing the touch driving signal to the at least one first
electrode, and provides the touch driving signal to the at least
one second electrode after providing the pre-setting dummy pulse
signal to the at least one second electrode.
19. The driver circuit of claim 13, wherein the circuitry provides
a pre-setting load free driving (LFD) signal to at least one of
gate lines or data lines of the display panel while the pre-setting
dummy pulse signal is provided to the at least one first electrode,
and wherein the pre-setting LFD signal has a same phase as the
pre-setting dummy pulse signal.
20. The driver circuit of claim 13, wherein during another display
mode following the touch sensing mode, the circuitry again provides
the common voltage to the electrodes, and during a post-setting
period after the circuitry provides the touch driving signal to the
at least one electrode and before the circuitry again provides the
common voltage to the electrodes, the circuitry provides a
post-setting signal to the electrodes that is same as the common
voltage.
21. (canceled)
22. The driver circuit of claim 13, wherein the pre-setting dummy
pulse signal has a same amplitude as the touch driving signal.
23. The driver circuit of claim 13, wherein the pre-setting dummy
pulse signal has a greater amplitude than the touch driving
signal.
24. The driver circuit of claim 13, wherein the touch driving
signal comprises one or more reset pulses and one or more real
touch driving pulses after the one or more reset pulses, and
wherein touch is not sensed from touch sensing data generated
responsive to the reset pulses, touch is sensed from touch sensing
data generated responsive to the one or more real touch driving
pulses.
25. A method for operating a touch sensitive display device that
comprises a display panel including a plurality of electrodes, the
method comprising: during a display mode, providing a common
voltage to the electrodes; during a touch sensing mode, providing a
touch driving signal to at least one first electrode of the
electrodes; and during a pre-setting period after the common
voltage is provided to the electrodes and before the touch driving
signal is provided to the at least one first electrode, providing a
pre-setting dummy pulse signal to the at least one first electrode,
and disregarding touch sensing data generated responsive to the
pre-setting dummy pulse signal, wherein the pre-setting dummy pulse
signal has a same phase as the touch driving signal.
26. The method of claim 25, further comprising, during the touch
mode: providing the touch driving signal to at least one second
electrode of the electrodes after providing the touch driving
signal to the at least one first electrode, and wherein the
pre-setting dummy pulse signal is not provided to the at least one
second electrode during the touch mode.
27. The method of claim 25, further comprising, during the touch
mode: providing the pre-setting dummy pulse signal to at least one
second electrode of the electrodes after providing the touch
driving signal to the at least one first electrode, and providing
the touch driving signal to the at least one second electrode after
providing the pre-setting dummy pulse signal to the at least one
second electrode.
28. The method of claim 25, further comprising: providing a
pre-setting load free driving (LFD) signal to at least one of the
gate lines or data lines while the pre-setting dummy pulse signal
is provided to the at least one first electrode, and wherein the
pre-setting LFD signal has a same phase as the pre-setting dummy
pulse signal.
29. The method of claim 25, further comprising: during another
display mode following the touch mode, again providing the common
voltage to the electrodes, and during a post-setting period after
the touch driving signal is provided to the at least one electrode
and before the common voltage is again provided to the electrodes,
providing a post-setting signal to the electrodes that is same as
the common voltage.
30. The method of claim 25, wherein the touch driving signal
comprises one or more reset pulses and one or more real touch
driving pulses after the one or more reset pulses, and the method
further comprises: not sensing touch from touch sensing data
generated responsive to the reset pulses, and sensing touch from
touch sensing data generated responsive to the one or more real
touch driving pulses.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from and the benefit under
U.S.C. .sctn.119(a) from Republic of Korea Patent Application
Number 10-2015-0142035 filed on Oct. 12, 2015, which is hereby
incorporated by reference for all purposes as if fully set forth
herein.
BACKGROUND
[0002] Field
[0003] The present disclosure relates to a touch circuit, a display
driver circuit, a touch display device, and a method of driving the
same.
[0004] Description of Related Art
[0005] In response to the development of the information society,
there is increasing demand for various types of display devices
able to display images. Currently, a range of display devices, such
as liquid crystal display (LCD) devices, plasma display panels
(PDPs) and organic light-emitting diode (OLED) display devices, are
in common use.
[0006] Many display devices provide a touch-based input system
enabling users to intuitively and conveniently input data or
instructions directly to a device, rather than using conventional
input systems, such as buttons, a keyboard, or a mouse.
[0007] In order to provide such a touch-based input system,
sensitivity to the touch of a user and the ability to accurately
detect the coordinates of a touch point are required.
[0008] In this regard, capacitive touch sensing technology is
commonly used, in which a plurality of touch electrodes (e.g. row
electrodes and column electrodes) are disposed on a touchscreen
panel (TSP) to detect a touch and the coordinates of a touch point
based on changes in capacitance between touch electrodes or changes
in capacitance between a touch electrode and a pointer, such as a
finger.
[0009] However, during touch driving and touch sensing, undesirable
parasitic capacitance may be generated in addition to capacitance
required for touch sensing.
[0010] According to capacitive touch sensing technology, such
undesirable parasitic capacitance may be problematic, for example,
increasing the load of a touch operation, decreasing the accuracy
of touch sensing, and in severe cases, rendering touch sensing
impossible.
[0011] When a display mode and a touch mode are undertaken by being
time-divided, an incorrect touch sensing result may be caused by
factors other than parasitic capacitance.
[0012] The above-described problems become exacerbated in display
devices in which a touchscreen panel (TSP) is disposed within a
display panel.
BRIEF SUMMARY
[0013] Various aspects of the present disclosure provide a touch
circuit, a display driver circuit, a touch display device, and a
method of driving the same able to improve the accuracy of touch
sensing by stabilizing touch sensing when display driving is ended
and touch driving begins to be performed.
[0014] Also provided are a touch circuit, a display driver circuit,
a touch display device, and a method of driving the same able to
minimize or remove the influence between a display mode and a touch
mode when the display mode and the touch mode are undertaken by
being time-divided, such that a display function and a touch
sensing function can be properly performed.
[0015] Also provided are a touch circuit, a display driver circuit,
a touch display device, and a method of driving the same able to
accurately perform touch driving and touch sensing without the
influence of ended display driving when display driving is ended
and touch driving begins to be performed, thereby providing an
accurate touch sensing result.
[0016] Also provided are a touch circuit, a display driver circuit,
a touch display device, and a method of driving the same able to
accurately perform display driving without the influence of ended
touch driving when touch driving is ended and display driving
begins to be performed, thereby improving image quality.
[0017] Also provided are a touch circuit, a display driver circuit,
a touch display device, and a method of driving the same able to
accurately perform touch driving and load free driving as well as
resultant touch sensing without the influence of ended display
driving when display driving is ended and both touch driving and
load free driving for removing parasitic capacitance begin to be
performed.
[0018] According to an aspect of the present disclosure, a touch
display device includes: a display panel on which N number of
common electrodes are disposed, wherein the N number of common
electrodes are categorized into M number of common electrode
groups, where 2.ltoreq.M.ltoreq.N; and a touch circuit sequentially
outputting a touch driving signal to the M number of common
electrode groups in order to sequentially drive the M number of
common electrode groups during a touch mode.
[0019] In this touch display device, the touch circuit may output a
pre-setting signal before sequentially driving the M number of
common electrode groups.
[0020] According to another aspect of the present disclosure, a
touch display device includes: a display panel on which N number of
common electrodes are disposed; and a touch circuit driving the N
number of common electrodes during a touch mode that is performed
after a display mode.
[0021] In this touch display device, the touch circuit may supply a
pre-setting signal to at least one common electrode among the N
number of common electrodes before driving the N number of common
electrodes during the touch mode.
[0022] According to further another aspect of the present
disclosure, a method of driving a touch display device includes: a
display driving operation of applying a display mode voltage to N
number of common electrodes disposed on a display panel in a
display mode; and a touch driving operation of sequentially
applying a touch driving signal to the N number of common
electrodes in a touch mode.
[0023] The method may further include a pre-setting operation of
applying a pre-setting signal to at least one common electrode
among the N number of common electrodes before sequentially
applying the touch driving signal to the N number of common
electrodes before the touch driving.
[0024] According to still another aspect of the present disclosure,
a touch circuit includes: a touch driver circuit sequentially
outputting a touch driving signal to be applied to each of M number
of common electrode groups, where 2.ltoreq.M.ltoreq.N, in order to
sequentially drive the M number of common electrode groups into
which N number of common electrodes disposed on a display panel are
categorized, during a touch mode; a switch circuit sequentially
connecting the touch driver circuit to the M number of common
electrode groups according to a driving sequence of the M number of
common electrode groups; and a touch sensing circuit receiving a
touch sensing signal corresponding to each of the M number of
common electrode groups to which the touch driving signal is
applied through the switch circuit and sensing a touch based on the
touch sensing signal corresponding to each of the M number of
common electrode groups.
[0025] In this touch circuit, the touch driver circuit may output a
pre-setting signal to at least one common electrode group among the
M number of common electrode groups before sequentially driving the
M number of common electrode groups.
[0026] According to another aspect of the present disclosure, a
touch circuit includes: a touch driving module sequentially
outputting a touch driving signal to M number of common electrode
groups, where 2.ltoreq.M.ltoreq.N, into which N number of common
electrodes disposed on a display panel are categorized, during a
touch mode; and a touch sensing module sensing a touch based on a
touch sensing signal received from each of the M number of common
electrode groups.
[0027] In this touch circuit, the touch driving module may output a
pre-setting signal before sequentially outputting the touch driving
signal to the M number of common electrode groups.
[0028] According to further another aspect of the present
disclosure, a display driver circuit includes: a display driving
section outputting a display mode voltage to N number of common
electrodes disposed on a display panel during a display mode; and a
touch circuit section sequentially outputting a touch driving
signal to M number of common electrode groups, where
2.ltoreq.M.ltoreq.N, into which N number of common electrodes
disposed on a display panel are categorized, during a touch
mode.
[0029] In this display driver circuit, the touch circuit section
may output a pre-setting signal before sequentially outputting the
touch driving signal to the M number of common electrode
groups.
[0030] According to still another aspect of the present disclosure,
a display driver circuit includes: a data driver circuit outputting
a data voltage to a plurality of data lines disposed on a display
panel during a display mode; and a touch sensing signal detection
circuit sequentially detecting a touch sensing signal from M number
of common electrode groups, where 2.ltoreq.M.ltoreq.N, into which N
number of common electrodes disposed on the display panel are
categorized, during a touch mode.
[0031] In the display driver circuit, the touch sensing signal
detection circuit may extract a portion of a plurality of pulses of
the touch sensing signal.
[0032] According to present embodiments, it is possible to provide
the touch circuit, the display driver circuit, the touch display
device, and the method of driving the same able to improve the
accuracy of touch sensing by stabilizing touch sensing when display
driving is ended and touch driving begins to be performed.
[0033] According to present embodiments, it is possible to provide
the touch circuit, the display driver circuit, the touch display
device, and the method of driving the same able to minimize or
remove the influence between the display mode and the touch mode
when the display mode and the touch mode are undertaken by being
time-divided, such that the display function and the touch sensing
function can be properly performed.
[0034] According to the present embodiments, it is possible to
provide the touch circuit, the display driver circuit, the touch
display device, and the method of driving the same able to
accurately perform touch driving and touch sensing without the
influence of ended display driving when display driving is ended
and touch driving begins to be performed, thereby providing an
accurate touch sensing result.
[0035] According to the present embodiments, it is possible to
provide the touch circuit, the display driver circuit, the touch
display device, and the method of driving the same able to
accurately perform display driving without the influence of ended
touch driving when touch driving is ended and display driving
begins to be performed, thereby improving image quality.
[0036] According to the present embodiments, it is possible to
provide the touch circuit, the display driver circuit, the touch
display device, and the method of driving the same able to
accurately perform touch driving and load free driving as well as
resultant touch sensing without the influence of ended display
driving when display driving is ended and both touch driving and
load free driving for removing parasitic capacitance begin to be
performed.
[0037] In one embodiment, a touch sensitive display device
comprises a display panel including a plurality of electrodes. The
display device also comprises circuitry to drive the electrodes
during at least a display mode and a touch mode. During the display
mode, the circuitry provides a common voltage to the electrodes.
During the touch mode, the circuitry provides a touch driving
signal to at least one first electrode of the electrodes. During a
pre-setting period after the common voltage is provided to the
electrodes and before the touch driving signal is provided to the
at least one first electrode, the circuitry provides a pre-setting
dummy pulse signal to the at least one first electrode. During the
pre-setting period the circuitry disregards touch sensing data
generated responsive to the pre-setting dummy pulse signal.
[0038] In one embodiment, the touch sensitive display device
comprises a timing controller to generate a synchronization signal
having a first state during the touch mode and a second state
during the display mode. The pre-setting period can be during the
touch mode when the synchronization signal is in the first state.
Alternatively, the pre-setting period can be during the display
mode when the synchronization signal is in the second state.
[0039] In one embodiment, during the touch mode, the circuitry
provides the touch driving signal to at least one second electrode
of the electrodes after providing the touch driving signal to the
at least one first electrode. Also during the touch mode, the
circuitry does not provide the pre-setting dummy pulse signal to
the at least one second electrode.
[0040] In one embodiment, the circuitry provides the pre-setting
dummy pulse signal to at least one second electrode of the
electrodes after providing the touch driving signal to the at least
one first electrode. The circuitry also provides the touch driving
signal to the at least one second electrode after providing the
pre-setting dummy pulse signal to the at least one second
electrode.
[0041] In one embodiment, the display panel comprises a plurality
of data lines and a plurality of gate line. The circuitry provides
a pre-setting load free driving (LFD) signal to at least one of the
gate lines or data lines while the pre-setting dummy pulse signal
is provided to the at least one first electrode. The pre-setting
LFD signal also has a same phase as the pre-setting dummy pulse
signal.
[0042] In one embodiment, during another display mode following the
touch mode, the circuitry again provides the common voltage to the
electrodes. During a post-setting period after the circuitry
provides the touch driving signal to the at least one electrode and
before the circuitry again provides the common voltage to the
electrodes, the circuitry provides a post-setting signal to the
electrodes that is same as the common voltage.
[0043] In one embodiment, the pre-setting dummy pulse signal has a
same phase as the touch driving signal. The pre-setting dummy pulse
signal may have a same amplitude as the touch driving signal or
have a greater amplitude than the touch driving signal.
[0044] In one embodiment, the touch driving signal comprises one or
more reset pulses and one or more real touch driving pulses after
the one or more reset pulses. The circuitry does not sense touch
from touch sensing data generated responsive to the reset pulses
and senses touch from touch sensing data generated responsive to
the one or more real touch driving pulses.
[0045] In one embodiment, a driver circuit is disclosed that
includes the circuitry for driving the electrodes of the display
panel. In embodiment, a method of operation in the display panel is
disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0046] The above and other objects, features and advantages of the
present disclosure will be more clearly understood from the
following detailed description when taken in conjunction with the
accompanying drawings, in which:
[0047] FIG. 1 is a system configuration view illustrating a touch
display device according to embodiments of the present
disclosure;
[0048] FIG. 2 is a schematic diagram illustrating a touch system of
the touch display device according to the present embodiments;
[0049] FIG. 3 is a schematic configuration diagram of a touch
circuit of the touch system of the touch display device according
to the present embodiments;
[0050] FIG. 4 is a configuration diagram of the touch circuit of
the touch system of the touch display device according to the
present embodiments when N number of common electrodes are
sequentially driven;
[0051] FIG. 5 is a configuration diagram of the touch circuit of
the touch system of the touch display device according to the
present embodiments when N number of common electrodes categorized
into M number of common electrode groups are driven according to
the common electrode groups;
[0052] FIG. 6 is an equivalent circuit diagram illustrating the
principle of touch driving and touch sensing for the touch system
of the touch display device according to the present
embodiments;
[0053] FIG. 7 is a diagram illustrating main signals in the display
mode and the touch mode of the touch display device according to
the present embodiments;
[0054] FIG. 8 is a diagram illustrating a sensing destabilizing
phenomenon caused by display touch crosstalk in the touch display
device according to the present embodiments;
[0055] FIG. 9 to FIG. 11 are diagrams illustrating a sensing
destabilizing phenomenon caused by signal delay in the touch
display device according to the present embodiments;
[0056] FIG. 12 is a diagram illustrating a pre-setting scheme for
sensing stabilization in the touch display device according to the
present embodiments;
[0057] FIG. 13 is a diagram illustrating three types of time
periods in which a pre-setting signal for sensing stabilization is
output in the touch display device according to the present
embodiments;
[0058] FIG. 14 is a diagram illustrating signals applied to a
common electrode between the display mode and the touch mode when
the pre-setting scheme is utilized in the touch display device
according to the present embodiments;
[0059] FIG. 15 and FIG. 16 are diagrams illustrating examples of
signal waveforms in a pre-setting signal for sensing stabilization
in the touch display device according to the present
embodiments;
[0060] FIG. 17 is a diagram illustrating main signals in the
display mode and the touch mode when the pre-setting scheme is
utilized in the touch display device according to the present
embodiments;
[0061] FIG. 18 is a diagram illustrating a application of the
pre-setting scheme when driving is performed according to common
electrode groups in the touch display device according to the
present embodiments;
[0062] FIG. 19 is a diagram differently illustrating an application
of the pre-setting scheme when driving is performed according to
the common electrode groups in the touch display device according
to the resent exemplary embodiments;
[0063] FIG. 20 is a diagram illustrating noise reduction effects
that can be obtained using the pre-setting scheme for sensing
stabilization in the touch display device according to the present
embodiments;
[0064] FIG. 21 is a diagram illustrating the post-setting scheme
for display stabilization in the touch display device according to
the present embodiments;
[0065] FIG. 22 is a block diagram illustrating a touch circuit of
the touch display device according to the present embodiments;
[0066] FIG. 23 is a block diagram illustrating a touch IC of the
touch display device 100 according to the present embodiments;
[0067] FIG. 24 is a block diagram illustrating a display driver
circuit of the touch display device according to the present
embodiments;
[0068] FIG. 25 is a block diagram illustrating another display
driver circuit of the touch display device according to the present
embodiments; and
[0069] FIG. 26 is a flowchart illustrating a method of driving the
touch display device according to the present embodiments.
DETAILED DESCRIPTION
[0070] Reference will now be made in detail to embodiments of the
present disclosure, examples of which are illustrated in the
accompanying drawings. Throughout this document, reference should
be made to the drawings, in which the same reference numerals and
signs will be used to designate the same or like components. In the
following description of the present disclosure, detailed
descriptions of known functions and components incorporated herein
will be omitted in the case that the subject matter of the present
disclosure may be rendered unclear thereby.
[0071] It will also be understood that, while terms such as
"first," "second," "A," "B," "(a)" and "(b)" may be used herein to
describe various elements, such terms are only used to distinguish
one element from another element. The substance, sequence, order or
number of these elements is not limited by these terms. It will be
understood that when an element is referred to as being "connected
to" or "coupled to" another element, not only can it be "directly
connected" or "coupled to" the other element, but it can also be
"indirectly connected or coupled to" the other element via an
"intervening" element. In the same context, it will be understood
that when an element is referred to as being formed "on" or "under"
another element, not only can it be directly formed on or under
another element, but it can also be indirectly formed on or under
another element via an intervening element.
[0072] FIG. 1 is a system configuration view illustrating a touch
display device 100 according to embodiments of the present
disclosure.
[0073] Referring to FIG. 1, the touch display device 100 according
to the present embodiments is a device able to provide both an
image display function (display function) and a touch sensing
function.
[0074] Referring to FIG. 1, the touch display device 100 according
to the present embodiments includes a display panel 110, a data
driver 120, a gate driver 130, a controller 140, and the like in
order to provide the display function. On the display panel 110, a
plurality of data lines LD and a plurality of gate lines GL are
disposed, and a plurality of subpixels SP are arranged. The data
driver 120 drives the plurality of data lines LD, and the gate
driver 130 drives the plurality of gate lines GL. The controller
140 controls the data driver 120 and the gate driver 130.
[0075] The controller 140 controls the data driver 120 and the gate
driver 130 by supplying a variety of control signals to the data
driver 120 and the gate driver 130.
[0076] The controller 140 starts scanning based on timing realized
by each frame, outputs converted video data by converting video
data input from an external source into a data signal format
readable by the data driver 120, and at a suitable point in time,
regulates data processing in response to the scanning.
[0077] The controller 140 may be a timing controller used in a
typical display device or may be an integrated controller including
a timing controller and executing other control functions.
[0078] The data driver 120 drives the plurality of data lines DL by
supplying data voltages thereto. The data driver 120 is also
referred to as a "source driver."
[0079] The gate driver 130 sequentially drives the plurality of
gate lines GL by sequentially supplying a scanning signal thereto.
The gate driver 130 is also referred to as a "scanning driver."
[0080] The gate driver 130 sequentially supplies the scanning
signal having an on or off voltage to the plurality of gate lines
GL under the control of the controller 140.
[0081] When a specific gate line is opened by the gate driver 130,
the data driver 120 converts video data received from the
controller into analog data voltages and supplies the analog data
voltages to the plurality of data lines DL.
[0082] In FIG. 1, the data driver 120 is positioned on one side
(the upper side or the lower side) of the display panel 110.
However, the data driver 120 may be positioned on both sides (e.g.
both the upper side and the lower side) of the display panel 110
depending on the driving system, the design of the panel, or the
like.
[0083] The gate driver 130 is positioned on one side (the left side
or the right side) of the display panel 110 in FIG. 1. However, the
gate driver 130 may be positioned on both sides (e.g. both the left
side and the right side) of the display panel 110 depending on the
driving system, the design of the panel, or the like.
[0084] The controller 140 receives a variety of timing signals
including a vertical synchronization signal Vsync, a horizontal
synchronization signal Hsync, an input data enable (DE) signal, and
a clock signal from external sources (e.g. a host system), together
with input video data.
[0085] The controller 140 not only outputs converted video data by
converting video data input from an external source into a data
signal format readable by the data driver 120, but also outputs a
variety of control signals to the data driver 120 and the gate
driver 130 by generating the variety of control signals in response
to a variety of received timing signals, including a vertical
synchronization signal Vsync, a horizontal synchronization signal
Hsync, an input DE signal, and a clock signal, in order to control
the data driver 120 and the gate driver 130.
[0086] For example, the controller 140 outputs a variety of gate
control signals (GCSs) including a gate start pulse (GSP), a gate
shift clock (GSC) signal, and a gate output enable (GOE) signal in
order to control the gate driver 130.
[0087] Here, the GSP controls the operation start timing of the
gate driver integrated circuits (ICs) of the gate driver 130. The
GSC signal is a clock signal commonly input to the gate driver ICs
to control the shift timing of a scanning signal (gate pulse). The
GOE signal designates the timing information of the gate driver
ICs.
[0088] In addition, the controller 140 outputs a variety of data
control signals (DCSs) including a source start pulse (SSP), a
source sampling clock (SSC) signal, and a source output enable
(SOE) signal in order to control the data driver 120.
[0089] Here, the SSP controls the data sampling start timing of the
source driver ICs of the data driver 120. The SSC signal is a clock
signal controlling the data sampling timing of each of the source
driver ICs. The SOE signal controls the output timing of the data
driver 120.
[0090] The above-described data driver 120 may be implemented as
one or more source driver ICs.
[0091] Each of the source driver ICs may be connected to the
bonding pads of the display panel 110 by tape-automated bonding
(TAB) or chip-on-glass (COG) bonding, may be directly disposed on
the display panel 110, or in some cases, may be integrated with the
display panel 110, forming a portion of the organic display panel
110. Alternatively, each of the source driver ICs may be mounted on
a film connected to the display panel 110 by a chip-on film (COF)
method.
[0092] Each of the source driver ICs may include a shift register,
a latch circuit, a digital-to-analog converter (DAC), an output
buffer, and the like.
[0093] In some cases, each of the source driver ICs further
includes an analog-to-digital converter (ADC).
[0094] The gate driver 130 includes one or more gate driver
ICs.
[0095] Each of the gate driver ICs may be connected to the bonding
pads of the display panel 110 by tape-automated bonding (TAB) or
chip-on-glass (COG) bonding, may be implemented as a gate-in-panel
(GIP)-type IC directly disposed on the display panel 110, or in
some cases, may be integrated with the display panel 110, forming a
portion of the display panel 110. Alternatively, each of the gate
drivers IC may be mounted on a film connected to the display panel
110 by a chip-on film (COF) method.
[0096] Each of the gate drivers IC may include a shift register, a
level shifter, and the like.
[0097] The touch display device 100 according to the present
embodiments may include one or more source printed circuit boards
(S-PCBs) required for circuit-connection to the data driver 120 and
a control printed circuit boards (C-PCB) on which control
components, such as the controller 140, and a variety of electronic
devices are mounted.
[0098] Each of the S-PCBs may have a source driver IC mounted
thereon, or a film on which the source driver IC is mounted may be
connected to each S-PCB.
[0099] The C-PCB may have the controller 140, a power control
circuit (420 in FIG. 4), and the like mounted thereon, in which the
controller 140 controls the operations of the data driver 120, the
gate driver 130, and the like, and the power control circuit
supplies a variety of voltages or currents to or controls the
supply of the variety of voltages or currents to the display panel
110, the data driver 120, the gate driver 130, and the like.
[0100] The S-PCBs and the C-PCB may be connected by means of at
least one connecting member.
[0101] The connecting member may be a flexible printed circuit
(FPC), a flexible flat cable (FFC), or the like.
[0102] The S-PCBs and the C-PCB may be integrated as a single
PCB.
[0103] In the touch display device 100 according to the present
embodiments, the data driving function and the gate driving
function can be provided by an integrated driver in which the data
driver 120 and the gate driver 130 are unified.
[0104] In this case, the touch display device 100 according to the
present embodiments may include at least one driver IC providing
both the data driving function and the gate driving function.
[0105] The touch display device 100 according to the present
embodiments may be, for example, a device selected from among
various types of devices, such as a liquid crystal display (LCD)
device, an organic light-emitting diode (OLED) display device, a
plasma display device, and the like.
[0106] By the way, the touch display device 100 according to the
present embodiments includes a touch system in order to provide the
touch function.
[0107] Hereinafter, the touch system of the touch display device
100 according to the present embodiments will be described in
detail.
[0108] FIG. 2 is a schematic diagram illustrating the touch system
of the touch display device 100 according to the present
embodiments.
[0109] Referring to FIG. 2, the touch system of the touch display
device 100 according to the present embodiments includes a
plurality of touch electrodes acting as touch sensors, a touch
circuit 200 performing touch sensing by driving the plurality of
touch electrodes, and the like.
[0110] In the touch system of the touch display device 100
according to the present embodiments, the plurality of touch
electrodes are disposed on the display panel 110.
[0111] That is, in the touch display device 100 according to the
present embodiments, the display panel 110 has a touchscreen panel
(TSP) disposed therein.
[0112] In addition, in the touch display device 100 according to
the present embodiments, the plurality of touch electrodes may act
not only as the touch sensors, but also as display electrodes
associated with the display function.
[0113] In this connection, hereinafter, the touch electrodes will
be described as common electrodes CE.
[0114] Here, the term "common" means that the common electrodes CE
are in common use as the display electrodes and the touch
electrodes.
[0115] When the plurality of common electrodes CE are used as the
touch electrodes, a touch driving signal (TDS) is sequentially
applied to the plurality of common electrodes CE.
[0116] When the plurality of common electrodes CE are used as the
display electrodes, a display mode voltage is simultaneously
applied to the plurality of common electrodes CE.
[0117] When the plurality of common electrodes CE are used as the
display electrodes, each of the common electrodes CE may be an
electrode corresponding to a pixel electrode present in each
subpixel area.
[0118] In this case, the display mode voltage applied to the
plurality of CEs may be a common voltage Vcom corresponding to a
pixel voltage (a data voltage or a voltage corresponding thereto)
applied to pixel electrodes.
[0119] N number common electrodes CE (N.gtoreq.2) are disposed on
the display panel 110.
[0120] Each of the common electrodes CE may have the shape of a
block, as illustrated in FIG. 2. This is not intended to be
limiting, and the common electrodes may have any shape as long as
the common electrodes are separated from each other.
[0121] The N number of common electrodes CE disposed within the
display panel 110 may be arranged in a matrix, as illustrated in
FIG. 2.
[0122] The N number of common electrodes disposed on the display
panel 110 may be categorized into M number of common electrode
groups GE #1, . . . , and GE #M, where 2.ltoreq.M.ltoreq.N.
[0123] According to this categorization, each of the common
electrode groups includes N/M number of common electrodes CE.
[0124] The N/M number of common electrodes CE of each common
electrode group are simultaneously touch-driven. The simultaneous
touch driving of the common electrode group can be interpreted as
the N/M number of common electrodes CE of the common electrode
group being simultaneously driven.
[0125] When the number N of the common electrodes is equal to the
number M of the common electrode groups, each of the common
electrode groups includes a single common electrode CE. That is,
the single common electrode CE forms a common electrode group. In
this case, to drive a common electrode group has the same meaning
as to drive a common electrode CE.
[0126] Referring to FIG. 2, the touch circuit 200 can provide a
touch driving function of sending a touch driving signal to the
common electrodes CE and a touch sensing function of detecting a
touch or calculating the coordinates of a touch point by receiving
a touch sensing signal (TSS) from at least one common electrode
among the common electrodes CE to which the touch driving signal is
applied.
[0127] Regarding the touch driving function, in a time period
determined for the touch driving, the touch circuit 200 can
sequentially output a touch driving signal to the M number of
common electrode groups in order to sequentially drive the M number
of common electrode groups.
[0128] Regarding the touch sensing function, the touch circuit 200
can receive a TSS from a common electrode CE to which the touch
driving signal TDS is applied and subsequently detect a touch or
calculate the coordinates of a touch point by sensing capacitance
(or a voltage or a charge) or a variation in capacitance (or a
change in voltage or a change in charge) in the corresponding
common electrode CE.
[0129] Here, the touch circuit 200 is electrically connected to the
N number of common electrodes CE through N number of sensing lines
SL.
[0130] The touch circuit 200 receives the TSS by sending the touch
driving signal TDS to a single common electrode CE through a single
sensing line SL.
[0131] Regarding the display function, the data driver 120, a power
control circuit, or the other power supply can simultaneously
supply display mode voltages to the N number of common electrodes
CE through the N number of sensing lines SL.
[0132] The above-described touch circuit 200 may be formed of a
plurality of functional components or one or more touch ICs in
order to provide both the touch driving function and the touch
sensing function.
[0133] In addition, some portions of the plurality of components of
the touch circuit 200 may be formed as a separate circuit and the
other portions of the plurality of components of the touch circuit
200 may be situated within the other driving chip.
[0134] Hereinafter, as illustrated in FIG. 2, the case that, when N
is 12, 12 common electrodes CE are disposed on the display panel
110, in a matrix consisting of 3 rows and 4 columns, will be
described for the sake of convenience of explanation.
[0135] In addition, for example, 12 and 3 common electrode groups
are formed by categorizing the twelve common electrodes CE. That
is, the number of the common electrode groups is 12 or 3.
[0136] FIG. 3 is a schematic configuration diagram of the touch
circuit 200 of the touch system of the touch display device 100
according to the present embodiments, FIG. 4 is a configuration
diagram of the touch circuit of the touch system of the touch
display device 100 according to the present embodiments when N
number of common electrodes are sequentially driven, and FIG. 5 is
a configuration diagram of the touch circuit of the touch system of
the touch display device 100 according to the present embodiments
when N number of common electrodes categorized into M number of
common electrode groups are driven according to the common
electrode groups.
[0137] FIG. 4 illustrates an example in which 12 common electrodes
CE 11, CE 12, CE 13, CE 14, CE 21, CE 22, CE 23, CE 24, CE 31, CE
32, CE 33, and CE 34 are categorized into 12 common electrode
groups GE #1, GE #2, . . . , and GE #12 (M=12). In this case, each
of the common electrodes forms a common electrode group.
[0138] FIG. 5 illustrates an example in which 12 common electrodes
CE 11, CE 12, CE 13, CE 14, CE 21, CE 22, CE 23, CE 24, CE 31, CE
32, CE 33, and CE 34 are categorized into 3 common electrode groups
GE #1, GE #2, and GE #3 (M=3).
[0139] In this case, each of the common electrode groups includes 4
common electrodes. Specifically, common electrode group GE #1
includes CE 11, CE 12, CE 13, and C14, common electrode group GE #2
includes CE 21, CE 22, CE 23, and C24, and common electrode group
GE #3 includes CE 31, CE 32, CE 33, and C34.
[0140] The number of common electrodes belonging to a single common
electrode group is obtained by dividing the number N of common
electrodes by the number M of the common electrode groups.
[0141] The number of common electrodes belonging to a single common
electrode group is equal to the number of common electrodes that
can be simultaneously touch-driven.
[0142] Referring to FIG. 3, the touch circuit 200 of the touch
system of the touch display device 100 according to the present
embodiments includes, for example, a signal providing circuit 310,
a switch circuit 320, a touch sensing signal detection circuit 330,
a sensing data generator circuit 340, a touch sensing circuit 350,
and the like.
[0143] The signal providing circuit 310 provides a touch driving
signal TDS.
[0144] One end of the switch circuit 320 is connected to the signal
providing circuit 310, and the other end of the switch circuit 320
is connected to N number of signal lines SL 11, SL 12, SL 13, SL
14, SL 21, SL 22, SL 23, SL 24, SL 31, SL 32, SL 33, and SL 34.
[0145] The N number of signal lines SL 11, SL 12, SL 13, SL 14, SL
21, SL 22, SL 23, SL 24, SL 31, SL 32, SL 33, and SL 34 are
connected to N number of common electrodes CE 11, CE 12, CE 13, CE
14, CE 21, CE 22, CE 23, CE 24, CE 31, CE 32, CE 33, and CE 34 in a
corresponding manner.
[0146] The switch circuit 320 sequentially connects one or more
common electrodes to the signal providing circuit 310 according to
the touch driving sequence of the N number of common electrodes CE
11, CE 12, CE 13, CE 14, CE 21, CE 22, CE 23, CE 24, CE 31, CE 32,
CE 33, and CE 34.
[0147] Consequently, the touch driving signal TDS provided by the
signal providing circuit 310 is sequentially transferred to one or
more sensing lines through the switch circuit 320, whereby the
touch driving signal TDS is sequentially applied to the one or more
common electrodes that are to be touch-driven.
[0148] The touch sensing signal detection circuit 330 can detect
the touch sensing signal TSS, received from the one or more common
electrodes (included in the common electrode group) to which the
touch driving signal TDS is applied, by means of the switch circuit
320.
[0149] The sensing data generator circuit 340 generates sensing
data based on the touch sensing signal detected from each common
electrode.
[0150] The touch sensing circuit 350 senses a touch based on the
sensing data. Here, to sense the touch means to detect a touch or
calculate the coordinates of a touch point.
[0151] Referring to FIG. 4 and FIG. 5, the signal providing circuit
310 includes, for example, a pulse generator 410 generating a pulse
modulation signal (e.g. a pulse width modulation signal) and the
power control circuit 420 providing a touch driving signal TDS
generated based on the pulse modulation signal.
[0152] Referring to FIG. 4 and FIG. 5, the touch sensing signal
detection signal 330 includes one or more analog front ends
(AFEs).
[0153] The touch sensing signal detection signal 330 may include
one AFE, as illustrated in FIG. 4, or may include two or more AFEs
AFE #1, AFE #2, AFE #3, and AFE #4, as illustrated in FIG. 5.
[0154] Referring to FIG. 4 and FIG. 5, the switch circuit 320
includes one or more multiplexers.
[0155] Specifically, as illustrated in FIG. 4, when a single AFE is
provided, the switch circuit 320 includes a single multiplexer MUX.
As illustrated in FIG. 5, when four AFEs AFE #1, AFE #2, AFE #3,
and AFE #4 are provided, the switch circuit 320 includes 4
multiplexers MUX #1, MUX #2, MUX #3, and MUX #4.
[0156] That is, the number of the multiplexers is equal to the
number of the AFEs.
[0157] The number of the multiplexers and the number of the AFEs
may vary depending on the level to which the common electrodes are
grouped.
[0158] That is, the number of the multiplexers and the number of
the AFEs increase with increases in the level to which the common
electrodes are grouped, i.e. decreases in the number M of the
common electrode groups.
[0159] The embodiment of FIG. 5 indicates that the common
electrodes are grouped to a high level, i.e. the number M of the
common electrode groups is small. Thus, the number the multiplexers
and the number of the AFEs are increased.
[0160] Referring to FIG. 4 and FIG. 5, each of the number of the
multiplexers and the number of the AFEs is equal to the number of
common electrodes belonging to a single common electrode group.
[0161] Here, the number of the common electrodes belonging to a
single common electrode group is N/M, obtained by dividing the
number N of the common electrodes by the number M of the common
electrode groups.
[0162] Each of the number of the multiplexers and the number of the
AFEs is equal to the number of the common electrodes that can be
simultaneously touch-driven.
[0163] Referring to FIG. 4 and FIG. 5, each of the multiplexers is
an M:1 multiplexer considering that a TDS provided by the power
control circuit 420 is output through one signal line from among
the M number of signal lines or a TSS from one signal line from
among the M number of signal lines is transferred to the
corresponding AFE.
[0164] In the embodiment of FIG. 4 where M=12, a single multiplexer
MUX is a 12:1 multiplexer. In the embodiment of FIG. 5 where M=3,
each of 4 (=12/3) multiplexers MUX #1, . . . , and MUX #4 is a 3:1
multiplexer.
[0165] Referring to FIG. 4 and FIG. 5, the sensing data generator
circuit 340 includes an ADC generating sensing data by converting a
detected TSS into digital data.
[0166] Referring to FIG. 4 and FIG. 5, the touch sensing circuit
350 and the pulse generator 410 may be implemented as separate
components, or may be implemented as a single micro-control unit
(MCU).
[0167] Referring to FIG. 4 and FIG. 5, the switch circuit 320, the
touch sensing signal detection circuit 330, and the sensing data
generator circuit 340 may be separately formed. As an alternative,
at least one of the switch circuit 320, the touch sensing signal
detection circuit 330, and the sensing data generator circuit 340
may be included in a display driving chip together with a data
driver circuit or may be included within the data driver
circuit.
[0168] FIG. 6 is an equivalent circuit diagram illustrating the
principle of touch driving and touch sensing for the touch system
of the touch display device 100 according to the present
embodiments.
[0169] Referring to FIG. 6, the touch system performs touch driving
and touch sensing by using an integrator 600.
[0170] The integrator 600 may include a feedback capacitor Cfb and
an amplifier including a positive terminal (+), a negative terminal
(-) functioning as an input terminal, and an output terminal.
[0171] The integrator 600 may output an integral value with respect
to a voltage of a signal input to the input terminal.
[0172] A touch driving signal TDS is input to the positive terminal
(+) of the amplifier in the integrator 600 and is applied to a
common electrode CEs to be touch-driven and touch-sensed, which is
electrically connected to the negative terminal (-) of the
amplifier.
[0173] According to the presence or absence of a touch, that is,
the presence or absence of a formation of a capacitor between the
common electrode CEs and a pointer such as a finger and a pen, a
total capacitance of the amplifier in the integrator 600, connected
to the negative terminal (-) (input terminal), is changed, and the
change in the total capacitance is output to the output terminal of
the amplifier in the integrator 600 as a touch sensing signal
TSS.
[0174] In the case of the presence of the pointer, the total
capacitance of the amplifier in the integrator 600 connected to the
negative terminal (-) (input terminal) may be determined by an
absolute capacitance Cab of the common electrode CEs and a
capacitance Cf between the common electrode CEs and the
pointer.
[0175] In the case of the absence of the pointer, the total
capacitance of the amplifier in the integrator 600 connected to the
negative terminal (-) (input terminal) may be determined by the
absolute capacitance Cab of the common electrode CEs.
[0176] At the time of touch driving, when the touch driving signal
TDS is applied to the common electrode CEs to be touch-driven and
touch-sensed, parasitic capacitance Cp may be unnecessarily
generated between the common electrode CEs and a pattern, such as a
data line, a gate line, or other common electrodes CEo, disposed on
the display panel 110.
[0177] When the parasitic capacitance Cp is generated, the total
capacitance may be determined by the absolute capacitance Cab of
the common electrode CEs, the capacitance Cf between the common
electrode CEs and the pointer, and the parasitic capacitance
Cp.
[0178] Therefore, as the parasitic capacitance Cp is generated, the
total capacitance may be changed, and the touch sensing signal TSS
may be changed according to the change in the total capacitance.
The change in the touch sensing signal TSS may considerably
decrease touch sensing accuracy.
[0179] Therefore, when the touch driving signal TDS is applied to
the common electrode CEs to be touch-driven and touch-sensed, the
touch system according to the present embodiments performs load
free driving (LFD) that applies a signal corresponding to the touch
driving signal TDS to the pattern disposed on the display panel
110.
[0180] The LFD may be a driving technique that prevents the
generation of the parasitic capacitance Cp acting as a load at the
time of touch driving and may be performed together with touch
driving.
[0181] The pattern of conductive elements allowing for the LFD is
referred to as a load free driving pattern (LFD pattern), and a
signal applied to the LFD pattern is referred to as a load free
driving signal (LFD signal).
[0182] The LFD pattern may be all of electrodes and lines that are
disposed around the common electrode CEs to which the touch driving
signal TDS is applied and are able to generate the parasitic
capacitance Cp together with the common electrode CEs and may be,
for example, at least one of the data line DL, the gate line GL,
and the other common electrodes CEo to which the touch driving
signal TDS is not applied.
[0183] FIG. 7 is a diagram illustrating main signals in the display
mode and the touch mode of the touch display device 100 according
to the present embodiments.
[0184] Referring to FIG. 7, the display mode and the touch mode may
be time-divided and may be alternately performed.
[0185] Referring to FIG. 7, the touch system and display driving
configurations in the touch display device 100 may recognize the
display mode and the touch mode through a touch sync signal Touch
Sync. The touch sync signal Touch Sync may be a control signal
output from the controller 140 or the micro control unit MCU.
[0186] The signal level or state of the touch synch signal Touch
Sync indicates whether the system is in a display mode or a touch
mode. When a signal level of the touch sync signal Touch Sync is in
a high state (or low state), the display mode may be performed, and
when the signal level of the touch sync signal Touch Sync is in a
low state (or high state), the touch mode may be performed.
[0187] The main signals illustrated in FIG. 7 are signals
corresponding to a case in which the common electrode CE, the data
line DL, and the gate line GL are load-free-driven.
[0188] Referring to FIG. 7, during the touch mode, a touch driving
signal TDS is applied to a common electrode CEs that is being
touch-driven. A common electrode load free driving signal Vcom-LFD
is applied to a different common electrode CEo that is being
load-free-driven. At least one of a phase or an amplitude of the
common electrode load free driving signal Vcom-LFD corresponds to
the touch driving signal TDS.
[0189] The other common electrode CEo being load-free-driven may be
one or more common electrodes CEo adjacent to the common electrode
CEs being touch-driven or may be all remaining common electrodes
CEo.
[0190] During the display mode, a display mode voltage Vcom is
applied to all of the common electrodes CE.
[0191] Referring to FIG. 7, during the touch mode, a gate load free
driving signal GATE-LFD is applied to a gate line GL(n-1) and a
gate line GL(n), which are load-free-driven. At least one of a
phase and an amplitude of the gate load free driving signal
GATE-LFD corresponds to the touch driving signal TDS.
[0192] The gate line GL(n-1) and the gate line GL(n) being
load-free-driven may be at least one gate line adjacent to the
common electrode CEs being touch-driven and may be all of gate
lines.
[0193] During the display mode, a scan signal SCAN(n-1) is applied
to the (n-1).sup.th gate line GL(n-1), and a scan signal SCAN(n) is
applied to the n.sup.th gate line GL(n).
[0194] Referring to FIG. 7, during the touch mode, a data load free
driving signal DATA-LFD is applied to a data line DL being
load-free-driven. At least one of a phase and an amplitude of the
data load free driving signal DATA-LFD corresponds to the touch
driving signal TDS.
[0195] The data line DL being load-free-driven may be at least one
data line adjacent to the common electrode CEs being touch-driven
and may be all data lines.
[0196] During the display mode, a data voltage Vdata may be applied
to the data line DL. When the touch display device 100 is a liquid
crystal display device, while a polarity is inversed in every
display mode, the data voltage Vdata may be applied.
[0197] Hereinafter, a sensing destabilizing phenomenon and a touch
sensing noise according to the sensing destabilizing phenomenon
will be described, the sensing destabilizing phenomenon occurring
in a case in which the display mode and the touch mode are
performed by being time-divided and in a case in which the LFD is
applied.
[0198] FIG. 8 is a diagram illustrating a sensing destabilizing
phenomenon caused by display touch crosstalk in the touch display
device 100 according to the present embodiments.
[0199] As described above, since the common electrode CE is a
common mode electrode that operates as a touch electrode in the
touch mode and operates as a display electrode in the display mode,
the touch display device 100 alternately performs a display
function and a touch sensing function by dividing one frame into
the display mode and the touch mode.
[0200] Referring to FIG. 8, when the common electrode CE enters the
touch mode from the display mode, the common electrode CE receives
the touch driving signal TDS but may be in a "sensing-destabilized
state" in which the common electrode CE is not ready to normally
start touch driving and touch sensing (set a voltage state).
[0201] In other words, after the display mode is ended, as the
touch mode is performed, when the touch driving signal TDS is
abruptly applied to the common electrode CE to which the display
mode voltage Vcom is applied during the display mode, the common
electrode CE may not rapidly become a voltage state required for
the touch mode.
[0202] When touch sensing is performed in the "sensing-destabilized
state" of the common electrode CE, sensing data may include a touch
sensing noise. Therefore, an accurate touch sensing result may not
be acquired.
[0203] More specifically, after the display mode is ended, when the
touch mode is performed to perform touch driving and touch sensing,
a display image pattern displayed during the display mode may
appear as the touch sensing signal TSS or may distort the touch
sensing signal TSS. This phenomenon is referred to as "display
touch crosstalk."
[0204] The display image pattern, which appears as the touch
sensing signal TSS and distorts the touch sensing signal TSS in the
touch mode, is referred to as a "touch sensing noise."
[0205] As a result, when the touch mode is performed immediately
after the display mode is ended, the sensing destabilizing
phenomenon may be caused by the display touch crosstalk in which
the display image pattern displayed on a screen in the display mode
appears as the touch sensing signal TSS, that is, the touch sensing
noise and distorts the touch sensing signal TSS.
[0206] FIG. 9 to FIG. 11 are diagrams illustrating a sensing
destabilizing phenomenon caused by signal delay in the touch
display device 100 according to the present embodiments.
[0207] Referring to FIG. 9, as described above, a signal
transmission pathway through which the touch driving signal TDS,
output from the power control circuit 420 of the signal providing
circuit 310 and passing through the multiplexer MUX, is transferred
to the common electrode CEs touch-driven and touch-sensed is
different from a signal transmission pathway through which the
common electrode load free driving signal Vcom-LFD, output from the
power control circuit 420 and passing through the multiplexer MUX,
is transferred to the common electrode CEo being
load-free-driven.
[0208] Referring to FIG. 9, the touch driving signal TDS passing
through the multiplexer MUX is transferred to the common electrode
CEs touch-driven and touch-sensed through the integrator 600. The
common electrode load free driving signal Vcom-LFD does not pass
through the integrator 600 and is directly transferred to the
common electrode CEo being load-free-driven.
[0209] Therefore, a length Ltds of the signal transmission pathway
in which the touch driving signal TDS is transferred to the common
electrode CEs touch-driven and touch-sensed is greater than a
length Llfd of the signal transmission pathway in which the common
electrode free driving signal Vcom-LFD is transferred to the common
electrode CEo being load-free-driven.
[0210] In addition, a process of passing the touch driving signal
TDS from the negative terminal (-) of the integrator 600 to the
positive terminal (+) thereof, is required for transferring the
touch driving signal TDS to the common electrode CEs touch-driven
and touch-sensed, but the process is not required for transferring
the common load free driving signal Vcom-LFD to the common
electrode CEo being load-free-driven.
[0211] Due to the points described above, although the touch
driving signal TDS and the common electrode free driving signal
Vcom-LFD output from the power control circuit 420 have the same
signal waveform (for example, the same phase and the same
amplitude), when the touch driving signal TDS and the common
electrode free driving signal Vcom-LFD are actually applied to the
common electrode CEs touch-driven and touch-sensed and the common
electrode CEo being load-free-driven, respectively, signal
waveforms may be changed as illustrated in FIG. 10 or 11.
[0212] Referring to FIG. 10, since the length Ltds of the signal
transmission pathway for the touch driving signal TDS actually
applied to the common electrode CEs being touch-driven and
touch-sensed is greater than the length Llfd of the signal
transmission pathway for the common electrode load free driving
signal Vcom-LFD applied to the common electrode CEo being
load-free-driven (Ltds>Llfd), a signal transmission delay of the
touch driving signal TDS is greater than a signal transmission
delay of the common electrode load free signal Vcom-LFD, resulting
in delaying a rise time of the touch driving signal TDS.
[0213] The delay of the rise time may cause a signal transmission
delay.
[0214] Referring to FIG. 11, although signal rising starts at the
same time, due to the additional process of passing the touch
driving signal TDS through the integrator 600, the touch driving
signal TDS actually applied to the common electrode CEs
touch-driven and touch-sensed may have a longer rise time compared
to the common electrode load free driving signal Vcom-LFD actually
applied to the common electrode CEo being load-free-driven. The
rise time is a time elapsed until a voltage is increased to a
voltage (k times a maximum high level voltage, where k is a value
set to the range of 0.5 to 1) in which a change from a low level to
a high level is recognized.
[0215] That is, assuming that the rise time of the common electrode
load free driving signal Vcom-LFD applied to the common electrode
CEo being load-free-driven is TR1, the rise time of the touch
driving signal TDS actually applied to the common electrode CEs
touch-driven and touch-sensed is TR2, which is greater than
TR1.
[0216] In other words, the common electrode load free driving
signal Vcom-LFD applied to the common electrode CEo being
load-free-driven has a fast rise time, but the touch driving signal
TDS applied to the common electrode CEs touch-driven and
touch-sensed has a slow rise time.
[0217] The slow rise time of the touch driving signal TDS actually
applied to the common electrode CEs touch-driven and touch-sensed
also corresponds to a kind of signal delay.
[0218] As described above with reference to FIG. 9 to FIG. 11,
although the LFD is performed to prevent the generation of the
parasitic capacitance, the parasitic capacitance between the common
electrode CEs touch-driven and touch-sensed and the common
electrode CEo being load-free-driven may be generated by a signal
delay difference (i.e., 1. a signal delay difference due to a
transmission delay difference and 2. a signal delay difference due
to a rise time difference) between the touch driving signal TDS and
the common electrode free driving signal Vcom-LFD.
[0219] Therefore, the signal delay difference between the touch
driving signal TDS and the common load free driving signal Vcom-LFD
may act as touch sensing noise that causes the sensing
destabilizing phenomenon.
[0220] According to the present embodiments, a pre-setting scheme
for preparing to perform touch driving and touch sensing prior to
performing touch driving is provided as a method of minimizing the
sensing destabilizing phenomenon caused by the display touch
crosstalk and the sensing destabilizing phenomenon caused by the
signal delay difference.
[0221] Hereinafter, the pre-setting scheme for sensing
stabilization will be described in more detail.
[0222] FIG. 12 is a diagram illustrating the pre-setting scheme for
sensing stabilization in the touch display device 100 according to
the present embodiments.
[0223] Referring to FIG. 12, in the touch screen device 100
according to the present embodiments, before sequentially driving M
electrode groups (when M=n, N common electrodes), the touch circuit
200 may output a "pre-setting dummy pulse signal" to at least one
of the M common electrode groups. The outputting of the pre-setting
dummy pulse signal to the common electrode CE is referred to as
"pre-setting driving."
[0224] As described above, before the M common electrode groups (N
common electrodes when M=N) are sequentially driven, by applying
the "pre-setting dummy pulse signal" to the at least one of the M
common electrode groups, a voltage state required for touch driving
and touch sensing may rapidly occur in the common electrode CE to
which the pre-setting dummy pulse signal is applied.
[0225] That is, as the pre-setting dummy pulse signal is
pre-applied to the common electrode CE before the touch driving
signal TDS is applied, the display touch crosstalk can be removed
or reduced, and the signal delay difference can also be removed or
reduced, thereby stabilizing sensing.
[0226] Referring to FIG. 12, the pre-setting dummy pulse signal may
have substantially the same phase as the touch driving signal
TDS.
[0227] As described above, a state of the common electrode CE, to
which the pre-setting dummy pulse signal is applied before touch
driving, may be set to be substantially the same as a state of the
common electrode CE to which the touch driving signal TDS is
applied. This is done by setting the phase of the pre-setting dummy
pulse signal so as to be substantially the same as the phase of the
touch driving signal TDS, thereby efficiently stabilizing sensing
and efficiently performing pre-setting driving.
[0228] The common-electrode CE, to which the pre-setting dummy
pulse signal is applied, may be the common electrode CEs to which
the touch driving signal TDS is to initially be applied. The
common-electrode to which the pre-setting dummy pulse signal is
applied may also be one or more common electrodes CEo different
from the common electrode CEs, and may be all common
electrodes.
[0229] FIG. 13 is a diagram illustrating three types of time
periods in which a pre-setting dummy pulse signal for sensing
stabilization is output in the touch display device 100 according
to the present embodiments.
[0230] Referring to FIG. 13, the time period, i.e., a pre-setting
output time periods, in which the pre-setting dummy pulse signal is
output in the touch circuit 200, may be, for example, a time period
that is the front portion of the touch mode (Case 1), a time period
that is the end portion of the display mode (Case 2), or a time
period between the display mode and the touch mode (Case 3).
[0231] As described above, the pre-setting dummy pulse signal
output time period may be variously designed, thereby reducing the
influence of pre-setting driving on the display mode and the touch
mode or enabling efficient pre-setting driving.
[0232] FIG. 14 is a diagram illustrating signals applied to the
common electrode between the display mode and the touch mode when
the pre-setting scheme is utilized in the touch display device 100
according to the present embodiments.
[0233] Referring to FIG. 14, the pre-setting dummy pulse signal may
have a pulse signal form and may include, for example, one or more
dummy pulses.
[0234] For example, the pre-setting dummy pulse signal may include
1 to 4 dummy pulses.
[0235] Regarding the number of the pre-setting dummy pulses, when
the pre-setting dummy pulse signal is set to a small number of
pulses, while the influence is minimized on the display mode and/or
the touch mode, pre-setting driving may be performed, but
performance of sensing stabilization may be reduced according to
pre-setting driving.
[0236] On the contrary, when the pre-setting dummy pulse signal is
set to a large number of pulses, pre-setting driving may more
greatly influence the display mode and/or the touch mode, but the
performance of the sensing stabilization may be improved according
to pre-setting driving.
[0237] Therefore, the number of the dummy pulses constituting the
pre-setting dummy pulse signal may be efficiently adjusted by
taking into consideration the performance of the sensing
stabilization according to pre-setting driving and the efficiency
and performance of the display mode and/or the touch mode by
pre-setting driving.
[0238] The touch driving signal TDS may include, for example, one
or more reset pulses and one or more real touch driving pulses or
may include one or more real touch driving pulses.
[0239] The one or more reset pulses are pulses that function to
indicate a start of touch driving in the touch mode or function to
indicating a start of touch driving according to the common
electrode groups in the touch mode.
[0240] The one or more real touch driving pulses are pulses used in
actual touch driving.
[0241] The touch circuit 200 may sense a touch by extracting only a
portion of the touch sensing signal TSS corresponding to the real
touch driving pulses from which pulses corresponding to the
pre-setting dummy pulse signal and the reset pulse are removed, the
touch sensing signal TSS being received from the common electrode
groups to which the touch driving signal TDS is applied.
[0242] According to the signal waveform described above, the touch
circuit 200 may easily grasp the start of touch driving in the
touch mode or easily grasp the start of touch driving according to
the common electrode groups in touch mode by using use the one or
more reset pulses, and may sense a touch by grasping pulses
corresponding to the one or more reset pulses.
[0243] In addition, among a plurality of pulses constituting the
touch sensing signal TSS, only a pulse generated in relation to the
real touch driving pulse may be extracted and used in touch sensing
by removing pulses generated by pre-setting dummy pulses and reset
pulses which are not substantially related to touch driving but are
additionally applied to the common electrode. This can consequently
prevent the sensing destabilizing phenomenon caused by the sensing
display touch crosstalk and the sensing destabilizing phenomenon
caused by the signal delay difference and also performing accurate
touch sensing.
[0244] Specifically, when the dummy pulses or reset pulses are
being driven onto the common electrodes, a touch sensing signal TSS
is still generated from the dummy pulses and reset pulses, and the
ADC of the sensing data generator circuit 340 still generates
sensing data from TSS. However, the touch sensing circuit 350
simply disregards the sensing data as being dummy sensing data or
reset sensing data.
[0245] FIG. 15 and FIG. 16 are diagrams illustrating examples of
signal waveforms in the pre-setting dummy pulse signal for sensing
stabilization in the touch display device 100 according to the
present embodiments.
[0246] The pre-setting dummy pulse signal for sensing stabilization
may include one or more pulses and may be generated in various
signal waveforms. That is, the pre-setting dummy pulse signal may
be generated by variously setting an amplitude, a reference swing
voltage, and the like.
[0247] Cases A, B, C, and D are illustrated in FIG. 15 and FIG. 16
as examples according to a design change of an amplitude
.DELTA.Vpre and a voltage Vcom that is the reference of the
swing.
[0248] Referring to FIG. 15 and FIG. 16, the touch driving signal
TDS may be a pulse modulation signal that swings between a high
level voltage VH and a low level voltage VL, and the pre-setting
dummy pulse signal may be the pulse modulation signal like the
touch driving signal TDS.
[0249] Referring to FIG. 15 and FIG. 16, as in cases A and B, each
of amplitudes .DELTA.Vpre1 and .DELTA.Vpre3 in the pre-setting
dummy pulse signal may be substantially the same as an amplitude
.DELTA.V of the touch driving signal TDS.
[0250] As described above, when the pre-setting dummy pulse signal
having the same amplitude as the touch driving signal TDS is
generated, the pre-setting dummy pulse signal may be easily
generated.
[0251] Referring to FIG. 15 and FIG. 16, as in cases B and D, each
of amplitudes .DELTA.Vpre2 and .DELTA.Vpre4 in the pre-setting
dummy pulse signal may be greater than the amplitude .DELTA.V of
the touch driving signal TDS.
[0252] As described above, when the pre-setting dummy pulse signal
having the amplitude greater than the amplitude of the touch
driving signal TDS is generated, the common electrode CE may be
more rapidly set to a voltage state in which normal touch driving
and touch sensing are performed, thereby more rapidly achieving
sensing stabilization according to the pre-setting dummy pulse
signal.
[0253] Referring to FIG. 15 and FIG. 16, as in cases A and B, each
of the pre-setting dummy pulse signal and the touch driving signal
TDS is the pulse modulation signal that swings between the high
level voltage VH and the low level voltage VL. A low level voltage
of each of the pre-setting dummy pulse signal and the touch driving
signal TDS is a display mode voltage Vcom.
[0254] That is, in cases A and B, each of the pre-setting dummy
pulse signal and the touch driving signal TDS is a signal that
swings in a manner in which a voltage is raised to the high level
voltage and is returned to the low level voltage corresponding to
the display mode voltage Vcom.
[0255] Referring to FIG. 15 and FIG. 16, as in cases C and D, each
of the pre-setting dummy pulse signal and the touch driving signal
TDS is the pulse modulation signal that swings between the high
level voltage VH and the low level voltage VL. A high level voltage
of each of the pre-setting dummy pulse signal and the touch driving
signal TDS is higher than the display mode voltage Vcom. The low
level voltage of each of the pre-setting dummy pulse signal and the
touch driving signal TDS is lower than the display mode voltage
Vcom.
[0256] That is, in cases C and D, each of the pre-setting dummy
pulse signal and the touch driving signal TDS is the signal that
swings in a manner in which a voltage is raised to the high level
voltage and is returned to the low level voltage with respect to
the display mode voltage Vcom.
[0257] According to a swing property of the presetting signal and
the touch driving signal TDS described above, a voltage range used
for touch driving and pre-setting driving may be set to a voltage
range available in the touch display device 100.
[0258] FIG. 17 is a diagram illustrating main signals in the
display mode and the touch mode when the pre-setting scheme is
utilized in the touch display device 100 according to the present
embodiments.
[0259] Referring to FIG. 17, the display mode and the touch mode
may be time-divided and may be alternately performed.
[0260] The main signals illustrated in FIG. 17 are signals
corresponding to a case in which the LFD and the pre-setting
driving are performed on the common electrode CE, the data line DL,
and the gate line GL.
[0261] Referring to FIG. 17, according to the load free driving,
during the touch mode, load free driving signals Vcom-LFD,
GATE_LFD, and DATA_LFD, a phase of each of which is substantially
the same as a phase of the touch driving signal TDS, may be applied
to a load free driving pattern predefined on the display panel
110.
[0262] The load free driving pattern being load-free-driven may be,
for example, at least one data line DL, at least one gate line
GL(n-1) or GL(n), or at least one common electrode CE, may also be
a pattern such as an electrode or a voltage wiring, adjacent to the
common electrode CEs to which the touch driving signal TDS is
applied, and in some cases, may be all of patterns in the display
panel 110.
[0263] According to the load free driving described above, during
the touch mode, parasitic capacitance may be prevent from being
unnecessarily generated, thereby improving touch sensing
accuracy.
[0264] Referring to FIG. 17, during the touch mode, the touch
driving signal TDS is applied to the common electrode CEs being
touch-driven. In addition, the common electrode load free driving
signal Vcom-LFD is applied to a common electrode CEo corresponding
to the load free driving pattern being load-free-driven. At least
one of a phase and an amplitude of Vcom-LFD corresponds to the
touch driving signal TDS,
[0265] The common electrode CEo being load-free-driven may be one
or more common electrodes CEo adjacent to the common electrode CEs
being touch-driven or may be all remaining common electrodes
CEo.
[0266] Before the touch driving signal TDS is applied, the
pre-setting dummy pulse signal may be pre-applied to the relevant
common electrode CEs.
[0267] At this time, before the common electrode load free driving
signal Vcom-LFD is applied to the common electrode CEo
corresponding to the load free driving pattern, the pre-setting
dummy pulse signal (pre-setting dummy pulse signal for load free
driving) corresponding to the common electrode load free driving
signal Vcom-LFD may be pre-applied to the relevant common electrode
CEo.
[0268] During the display mode, a display mode voltage Vcom is
applied to all of the common electrodes CE.
[0269] Referring to FIG. 17, during the touch mode, the gate load
free driving signal GATE-LFD is applied to gate lines GL(n-1) and
GL(n) being load-free-driven. At least one of a phase and an
amplitude of GATE-LFD corresponds to the touch driving signal
TDS.
[0270] The gate lines GL(n-1) and the GL(n) being load-free-driven
may be at least one gate line adjacent to the common electrode CEs
being touch-driven and may be all of gate lines.
[0271] Before the common electrode load free driving signal
Vcom-LFD is applied to the gate lines GL(n-1) and GL(n)
corresponding to the load free driving pattern to be
load-free-driven, the pre-setting dummy pulse signal (pre-setting
dummy pulse signal for load free driving) corresponding to the gate
load free driving signal GATE-LFD may be pre-applied to the gate
lines GL(n-1) and GL(n).
[0272] During the display mode, a scan signal SCAN(n-1) is applied
to the (n-1).sup.th gate line GL(n-1), and a scan signal SCAN(n) is
applied to the n.sup.th gate line GL(n).
[0273] Referring to FIG. 17, during the touch mode, the data load
free driving signal DATA-LFD is applied to a data line DL being
load-free-driven. At least one of a phase and an amplitude of
DATA-LFD corresponds to the touch driving signal TDS.
[0274] The data line DL corresponding to the load free driving
pattern being load-free-driven may be at least one data line
adjacent to the common electrode CEs touch-driven and may be all of
data lines.
[0275] Before the data load free driving signal DATA-LFD is applied
to the data line DL corresponding to the load free driving pattern
to be load-free-driven, the pre-setting dummy pulse signal
(pre-setting dummy pulse signal for load free driving)
corresponding to the data load free driving signal DATA-LFD may be
pre-applied to the data line DL corresponding to the load free
driving pattern.
[0276] During the display mode, the relevant data voltage Vdata may
be applied to the data line DL. When the touch display device 100
is a liquid crystal display device, while a polarity is inversed in
every display mode, the data voltage Vdata may be applied.
[0277] As described above, even before the load free driving
signals Vcom_LFD, GATE_LFD, and DATA_LFD are applied, the
pre-setting dummy pulse signal may be applied to the load free
driving patterns CEo, GL, and DL, thereby improving the
stabilization of the load free driving. In addition, the touch
sensing accuracy may be improved by normally performing the load
free driving.
[0278] Hereinafter, as in FIG. 5, when touch driving is performed
according to the common electrode groups, a method of applying a
pre-setting scheme will be described. Of course, even in the case
of FIG. 4, assuming that one common electrode is one common
electrode group, it may be considered that touch driving is
performed according to the common electrode groups.
[0279] FIG. 18 is a diagram illustrating an application of the
pre-setting scheme when driving is performed according to the
common electrode groups in the touch display device 100 according
to the present embodiments.
[0280] Referring to FIG. 18, in the touch screen device 100
according to the present embodiments, when driving is performed
according to the common electrode groups, during the touch mode,
the touch circuit 200 may output the pre-setting dummy pulse signal
before outputting the touch driving signal TDS, to be applied to a
common electrode group GE #1 that is initially driven.
[0281] That is, although a plurality of common electrode groups GE
#1, GE #2, and GE #3 are touch-driven with respect to one touch
mode, the touch circuit 200 may generate the pre-setting dummy
pulse signal before applying the touch driving signal TDS to the
common electrode group GE #1 to be initially touch-driven.
[0282] Accordingly, although touch driving is performed according
to the common electrode groups, and the plurality of common
electrode groups GE #1, GE #2, and GE #3 are sequentially
touch-driven with respect to the one touch mode, pre-setting
driving may be efficiently performed by generating the pre-setting
dummy pulse signal only once.
[0283] FIG. 19 is a diagram differently illustrating an application
of the pre-setting scheme when driving is performed according to
the common electrode groups in the touch display device 100
according to the present exemplary embodiments.
[0284] Referring to FIG. 19, in the touch screen device 100
according to the present embodiments, when driving is performed
according to the common electrode groups, during the touch mode,
the touch circuit 200 may output the pre-setting dummy pulse signal
each time before outputting the touch driving signal TDS, to be
applied to each of common electrode groups that are sequentially
driven.
[0285] That is, although a plurality of common electrode groups GE
#1, GE #2, and GE #3 are touch-driven with respect to one touch
mode, the touch circuit 200 may generate the pre-setting dummy
pulse signal corresponding to each of the plurality of common
electrode groups GE #1, GE #2, and GE #3 before applying the touch
driving signal TDS to each of the plurality of common electrode
groups GE #1, GE #2, and GE #3.
[0286] Accordingly, although touch driving is performed according
to the common electrode groups, and the plurality of common
electrode groups GE #1, GE #2, and GE #3 are sequentially
touch-driven during one touch mode, performance of pre-setting
driving may be improved by generating the pre-setting dummy pulse
signal each time before each of the plurality of common electrode
groups GE #1, GE #2, and GE #3 is touch-driven.
[0287] FIG. 20 is a diagram illustrating noise reduction effects
that can be obtained using the pre-setting scheme for sensing
stabilization in the touch display device 100 according to the
present embodiments.
[0288] FIG. 20 is a diagram illustrating a position in which touch
sensing noise occurs when the pre-setting scheme is not applied and
a position in which touch sensing noise occurs when the pre-setting
scheme is applied.
[0289] Referring to FIG. 20, when the pre-setting scheme is not
applied, touch sensing noises occurring at a plurality of points
are observed since sensing is destabilized due to sensing display
touch crosstalk and signal delay.
[0290] In contrast, when the pre-setting scheme is applied,
positions at which sensing noises occur and the number of the
occurrence of sensing noises are significantly reduced, since the
pre-setting scheme can promote sensing stabilization by preventing
the sensing destabilization due to the display-touch crosstalk and
the sensing destabilization due to the signal delay.
[0291] The foregoing descriptions have been made to the pre-setting
scheme for preventing the sensing destabilizing phenomenon
occurring when the display mode is ended and the touch mode begins
to be performed or the sensing destabilizing phenomenon occurring
during the touch mode.
[0292] That is, the pre-setting scheme of previously supplying the
pre-setting dummy pulse signal to the N number of common electrodes
before the touch circuit 200 drives the N number of common
electrodes during the touch mode and the sensing stabilization
based on the pre-setting scheme have been described.
[0293] When the touch mode is ended and the display mode is
performed, touch-display crosstalk, i.e. the influence of the touch
driving and the load free driving performed in the touch mode,
remains in the display mode. Consequently, the display may be
destabilized or may malfunction.
[0294] Hereinafter, a post-setting scheme for preventing the
display destabilization will be described in brief.
[0295] FIG. 21 is a diagram illustrating the post-setting scheme
for display stabilization in the touch display device 100 according
to the present embodiments.
[0296] Referring to FIG. 21, in the touch display device 100
according to the present embodiments, after the touch circuit 200
applies a touch driving signal TDS to a common electrode group
among M number of common electrode groups that is the last to
operate during the touch mode, before a display mode voltage Vcom
is applied by the touch circuit 200 or the display driver circuit
in the display mode, a post-setting signal may be applied to the M
number of common electrode groups and/or the load-free driving
pattern.
[0297] For example, the above-mentioned post-setting signal may
have a voltage, the phase, amplitude, and the like of which
correspond to those of a display mode voltage.
[0298] Here, the display mode voltage may be a common voltage Vcom
applied to common electrodes CEs, which were subjected to touch
driving and load-free driving during the touch mode, for the
purpose of display driving, or may be a data voltage Vdata and a
gate voltage VGH and VGL applied to data lines DL and gate lines
GL, which were subjected to load-free driving during the touch
mode, for the purpose of display driving.
[0299] It is possible to prevent the touch-display crosstalk, i.e.
the influence of touch driving and load-free driving performed in
the touch mode remaining in the display mode, by preemptively
forming a display driving preparatory state by previously applying
a post-setting signal before display driving is performed
immediately after touch driving is ended. This can consequently
result in display stabilization and improve image quality in the
display mode.
[0300] Here, the touch-display crosstalk may mean a phenomenon in
which, in the display mode, the voltage state of a common electrode
is not directly changed to a display mode voltage Vcom from the
voltage state in which touch driving and touch sensing was
performed.
[0301] In addition, the touch-display crosstalk may mean a
phenomenon in which, in the display mode, the voltage state of the
load-free-driven common electrode CEo, the data line DL, and the
gate line GL is not directly changed to the display mode voltage
Vcom, Vdata, or SCAN(VGH, VGL) from the voltage state in which load
free driving was performed.
[0302] Here, as illustrated in FIG. 21, the time period in which
the post-setting signal is applied may be the end portion of the
touch mode. In some cases, the time period may be the front portion
of the display mode or a time period between the touch mode and the
display mode.
[0303] As above, the time period in which the post-setting signal
is applied may be variously designed, thereby reducing the
influence of post-setting driving on the display mode and the touch
mode or enabling efficient post-setting driving.
[0304] Hereinafter, the above-described respective components of
the touch display device 100 according to the present embodiments
will be briefly described again.
[0305] FIG. 22 is a block diagram illustrating the touch circuit
200 of the touch display device 100 according to the present
embodiments. In the following description, FIG. 3 to FIG. 5 will
also be referred to.
[0306] The touch circuit 200 of the touch display device 100
according to the present embodiments illustrated in FIG. 22
includes a touch driver circuit 2210, a switch circuit 320, and a
touch sensing circuit 2220.
[0307] During the touch mode, the touch driver circuit 2210 can
sequentially output a touch driving signal TDS that will be applied
to each of the M number of common electrode groups GE #1, GE #2,
and GE #3 (2.ltoreq.M.ltoreq.N) in order to sequentially drive the
M number of common electrode groups in which the N number of common
electrodes CE 11, CE 12, CE 13, CE 14, CE 21, CE 22, CE 23, CE 24,
CE 31, CE 32, CE 33, and CE 34 are categorized (N=12, where the
common electrodes are arranged in the 3.times.4 matrix, as in FIG.
3 and FIG. 5).
[0308] The switch circuit 320 sequentially connects the touch
driver circuit 2110 to the M number of common electrode groups GE
#1, GE #2, and GE #3 according to the driving sequence (GE
#1.fwdarw.GE #2.fwdarw.GE #3) of the M number of common electrode
groups GE #1, GE #2, and GE #3.
[0309] The touch sensing circuit 2220 can receive a touch sensing
signal TSS through the switch circuit 320, the touch sensing signal
corresponding to the common electrode groups to which the touch
driving signal TDS is applied through the switch circuit 320, and
sense a touch based on the touch sensing signal TSS corresponding
to each of the common electrode groups.
[0310] The touch driver circuit 2210 can output a pre-setting dummy
pulse signal to at least one common electrode group or all of the M
number of common electrode groups GE #1, GE #2, and GE #3 before
sequentially driving the M number of common electrode groups GE #1,
GE #2, and GE #3.
[0311] Referring to FIG. 22 together with FIG. 3 to FIG. 5, the
touch driver circuit 2210 further includes the signal providing
circuit 310, which outputs a touch driving signal TDS that will be
applied to the common electrode groups connected via the switch
circuit 320.
[0312] The signal providing circuit 310 may further output a
pre-setting dummy pulse signal before sequentially outputting the
touch driving signal TDS.
[0313] In addition, the touch sensing circuit 2220 further includes
the touch sensing signal detection circuit 330, the sensing data
generator circuit 340, the touch sensing circuit 350, and the like.
The touch sensing signal detection circuit 330 detects the touch
sensing signal TSS, received from the common electrode groups to
which the touch driving signal TDS is applied, through the switch
circuit. The sensing data generator circuit 340 generates sensing
data based on the touch sensing signal TSS detected by each of the
common electrode groups. The touch sensing circuit 350 senses a
touch based on the sensing data.
[0314] The use of the touch circuit 200 can prevent the sensing
destabilizing phenomenon due to the display-touch crosstalk and the
sensing destabilizing phenomenon due to the signal delay difference
by previously outputting a pre-setting dummy pulse signal to the
corresponding common electrode CE before outputting a touch driving
signal, thereby improving the accuracy of touch sensing.
[0315] The signal providing circuit 310 includes the pulse
generator 410 generating a pulse modulation signal (e.g. a pulse
width modulation signal), the power control circuit 420 providing a
touch driving signal TDS generated based on the pulse modulation
signal, and the like.
[0316] The power control circuit 420 can generate the pre-setting
dummy pulse signal and the touch driving signal TDS having the same
phase based on the phase of the pulse modulation signal.
[0317] In addition, the power control circuit 420 can generate a
pre-setting dummy pulse signal and a touch driving signal TDS
having the same amplitude or corresponding amplitudes based on the
amplitude of the pulse modulation signal.
[0318] Furthermore, the power control circuit 420 can convert the
level (amplitude) of the pre-setting dummy pulse signal and the
level (amplitude) of the touch driving signal TDS, which are
primarily formed based on the pulse modulation signal.
[0319] In addition, the signal providing circuit 310 may further
include a level shifter able to convert the level (amplitude) of
the pre-setting dummy pulse signal and the level (amplitude) of the
touch driving signal TDS output by the power control circuit
420.
[0320] The use of the signal providing circuit 310 can generate and
provide the touch driving signal TDS for the purpose of touch
driving and the pre-setting dummy pulse signal for the purpose of
efficient pre-setting driving while efficiently controlling the
touch driving signal TDS and the pre-setting dummy pulse
signal.
[0321] Referring to FIG. 22 together with FIG. 3 to FIG. 5, the
touch sensing signal detection circuit 330 includes one or more
AFEs.
[0322] Referring to FIG. 22 together with FIG. 3 to FIG. 5, the
switch circuit 320 includes one or more multiplexers.
[0323] In a single time period of the touch mode, the pre-setting
dummy pulse signal may be outputted one time, as in FIG. 18, or may
be outputted a number of times equal to the number of common
electrodes electrically connected to each of the multiplexers of
the switch circuit 320 (M, i.e. the number of the common electrode
groups).
[0324] As described above, pre-setting driving corresponding to the
structure of the switch circuit 320, such as the multiplexers and
the AFEs, can be provided. In addition, it is possible to design
the structure of the switch circuit 320, such as the multiplexers
and the AFEs, according to intended pre-setting driving.
[0325] The above-described touch circuit 200 can be formed as a
single IC. That is, a plurality of components or internal
components of the touch circuit 200 may be included as a module in
the single IC.
[0326] Alternatively, as illustrated in FIG. 4 or FIG. 5, a
plurality of components or the internal components of the touch
circuit 200 may be connected via signal lines, thereby forming a
separate circuit.
[0327] Two or more components among the plurality of components of
the touch circuit 200 or the internal components thereof may form a
separate single circuit or may be embodied as an internal module of
another driving chip.
[0328] For example, as illustrated in FIG. 4 or FIG. 5, the touch
sensing circuit 350 and the pulse generator 410 may be included as
an internal module of a micro-control unit (MCU). The power control
circuit 420 may be embodied as a separate power management IC. In
addition, the switch circuit 320, the touch sensing signal
detection circuit 330, the sensing data generator circuit 340, and
the like may be included together with a data driver circuit within
a driver chip 400, such as a display driver chip or a data driver
chip.
[0329] As described above, the positions and implementations of the
plurality of components or the internal components of the touch
circuit 200 may be varied in consideration of the functional and
operational characteristics thereof. This makes it possible to
design the touch circuit 200 that is structurally and functionally
optimized and the touch display device 100 including the same touch
circuit.
[0330] FIG. 23 is a block diagram illustrating a touch IC 2300 of
the touch display device 100 according to the present
embodiments.
[0331] Referring to FIG. 23, a description will be given of the
touch IC 2300 forming a portion or the entire portions of the touch
circuit 200.
[0332] Referring to FIG. 23, the touch IC 2300 includes a touch
driving module 2310 and a touch sensing module 2320. During the
touch mode, the touch driving module 2310 sequentially outputs a
touch driving signal TDS to M number of common electrode groups
(2.ltoreq.M.ltoreq.N) into which N number of common electrodes
disposed on the display panel 110 are categorized. The touch
sensing module 2320 senses a touch based on a touch sensing signal
TSS received from each of the common electrode groups.
[0333] The touch driving module 2310 can output pre-setting dummy
pulse signal before sequentially outputting the touch driving
signal TDS to the M number of common electrode groups.
[0334] The touch driving module 2310 is a module corresponding to
the touch driver circuit 2210 in FIG. 22, and the touch sensing
module 2320 is a module corresponding to the touch sensing circuit
2220 in FIG. 23.
[0335] Since the use of the touch IC 2300 outputs the pre-setting
dummy pulse signal to the corresponding common electrode before
outputting the touch driving signal TDS, it is possible to prevent
the sensing destabilizing phenomenon due to the display-touch
crosstalk and the sensing destabilizing phenomenon due to the
signal delay difference, thereby improving the accuracy of touch
sensing.
[0336] FIG. 24 is a block diagram illustrating a display driver
circuit 2400 of the touch display device 100 according to the
present embodiments.
[0337] Referring to FIG. 24, the display driver circuit 2400 of the
touch display device 100 according to the present embodiments
includes a display driving section 2410 and a touch circuit section
2420. During the display mode, the display driving section 2410
outputs a display mode voltage Vcom to the N number of common
electrodes CE disposed on the display panel 110. During the touch
mode, the touch circuit section 2420 sequentially outputs a touch
driving signal TDS to M number of common electrode groups
(2.ltoreq.M.ltoreq.N) into which N number of common electrodes are
categorized.
[0338] The touch circuit section 2420 can output a pre-setting
dummy pulse signal before sequentially outputting the touch driving
signal TDS to the M number of common electrode groups.
[0339] The display driving section 2410 and the touch circuit
section 2420 can operate based on relevant signals received from
the power control circuit 420.
[0340] The display driver circuit 2400 further includes a switch
circuit 320 having at least one multiplexer electrically connected
to the display driving section 2410 and the touch circuit section
2420.
[0341] The use of the display driver circuit 2400 can provide not
only the display function in which the N number of common
electrodes are driven as display electrodes, but also the touch
sensing function in which the N number of common electrodes are
driven as touch electrodes. In addition, a pre-setting dummy pulse
signal is output to the corresponding common electrode before the
touch driving signal TDS for touch driving is output to the
corresponding common electrode. This can consequently prevent the
sensing destabilizing phenomenon due to the display-touch crosstalk
and the sensing destabilizing phenomenon due to the signal delay
difference, thereby improving the accuracy of touch sensing.
[0342] FIG. 25 is a block diagram illustrating a display driver
circuit 2500 of the touch display device 100 according to the
present embodiments.
[0343] Referring to FIG. 25, the display driver circuit 2500 of the
touch display device 100 according to the present embodiments
includes a data driver circuit 2510 and the touch sensing signal
detection circuit 330. During the display mode, the data driver
circuit 2510 outputs data voltages to a plurality of data lines
disposed on the display panel 110. During the touch mode, the touch
sensing signal detection circuit 330 sequentially detects a touch
sensing signal TSS from M number of common electrode groups
(2.ltoreq.M.ltoreq.N) into which N number of common electrodes
disposed on the display panel 110 are categorized.
[0344] The touch sensing signal detection circuit 330 can extract
some pulses from among a plurality of pulses of the touch sensing
signal TSS.
[0345] Here, the extracted pulses may correspond to the real touch
driving pulses in FIG. 14 among the plurality of pulses of the
touch sensing signal TSS.
[0346] The touch sensing signal detection circuit 330 may include
the AFE illustrated in FIG. 22. In some cases, the touch sensing
signal detection circuit 330 may further include the sensing data
generator circuit 340 that can be an ADC.
[0347] The use of the display driver circuit 2500 can provide not
only the data driving function, but also the touch sensing function
when pre-setting driving for sensing stabilization is performed
before touch driving. In particular, among a plurality of pulses of
the touch sensing signal TSS, only a pulse generated in relation to
real touch driving may be extracted and used in touch sensing by
removing the pulses generated by pre-setting pulses and reset
pulses. This can consequently prevent the sensing destabilizing
phenomenon caused by the sensing display touch crosstalk and the
sensing destabilizing phenomenon caused by the signal delay
difference and also performing accurate touch sensing.
[0348] FIG. 26 is a flowchart illustrating a method of driving the
touch display device 100 according to the present embodiments.
[0349] Referring to FIG. 26, the method of driving the touch
display device 100 according to the present embodiments includes
display driving operation S2610 of applying a display mode voltage
to N number of common electrodes CE disposed on the display panel
110 in a display mode and touch driving operation S2630 of
sequentially applying a touch driving signal TDS to N number of
common electrodes in touch mode.
[0350] Referring to FIG. 26, the method of driving the touch
display device 100 according to the present embodiments further
includes pre-setting operation S2620 of applying a pre-setting
dummy pulse signal to at least one common electrode among the N
number of common electrodes CE before the touch driving operation
S2630 of sequentially applying the touch driving signal TDS to the
N number of common electrodes.
[0351] According to the driving method, the pre-setting dummy pulse
signal is applied to at least one common electrode group among M
number of common electrode groups (the N number of common
electrodes when M=N) before sequentially driving the M number of
common electrode groups. When touch driving is performed in
earnest, a voltage state required for touch driving and touch
sensing may rapidly occur in the common electrode(s) CE to which
the pre-setting dummy pulse signal is applied.
[0352] That is, as the pre-setting dummy pulse signal is
pre-applied to the common electrode CE before the touch driving
signal TDS is applied, the display touch crosstalk can be removed
or reduced, and the signal delay difference can also be removed or
reduced, thereby stabilizing sensing.
[0353] In addition, after the touch driving operation S2630,
post-setting operation S2640 of applying a post-setting signal to
the N number of common electrodes before a display mode voltage is
applied may be performed.
[0354] When the post-setting operation S2640 is further performed,
a display driving preparatory state is preemptively formed by
previously applying the post-setting signal before display driving
is performed immediately after touch driving is ended, thereby
preventing the touch-display crosstalk, i.e. the influence of touch
driving and load-free driving performed in the touch mode remaining
in the display mode. This can consequently result in display
stabilization and improve image quality in the display mode.
[0355] According to the present embodiments as set forth above, it
is possible to provide the touch circuit 200 or 2300, the display
driver circuit 2400 or 2500, the touch display device 100, and the
method of driving the same to be able to improve the accuracy of
touch sensing by stabilizing touch sensing when display driving is
ended and touch driving begins to be performed.
[0356] According to the present embodiments, it is possible to
provide the touch circuit 200 or 2300, the display driver circuit
2400 or 2500, the touch display device 100, and the method of
driving the same to be able to minimize or remove the influence
between the display mode and the touch mode when the display mode
and the touch mode are time-divided, such that the display function
and the touch sensing function can be properly performed.
[0357] According to the present embodiments, it is possible to
provide the touch circuit 200 or 2300, the display driver circuit
2400 or 2500, the touch display device 100, and the method of
driving the same to be able to accurately perform touch driving and
touch sensing without the influence of ended display driving when
display driving is ended and touch driving begins to be performed,
thereby providing an accurate touch sensing result.
[0358] According to the present embodiments, it is possible to
provide the touch circuit 200 or 2300, the display driver circuit
2400 or 2500, the touch display device 100, and the method of
driving the same to be able to accurately perform display driving
without the influence of touch driving when touch driving is ended
and display driving begins to be performed, thereby improving image
quality.
[0359] According to the present embodiments, it is possible to
provide the touch circuit 200 or 2300, the display driver circuit
2400 or 2500, the touch display device 100, and the method of
driving the same to be able to accurately perform touch driving and
load free driving as well as resultant touch sensing without the
influence of display driving when display driving is ended and both
touch driving and load free driving for removing parasitic
capacitance begin to be performed.
[0360] The foregoing descriptions and the accompanying drawings
have been presented in order to explain the certain principles of
the present disclosure. A person skilled in the art to which the
present disclosure relates can make many modifications and
variations by combining, dividing, substituting for, or changing
the elements without departing from the principle of the present
disclosure. The foregoing embodiments disclosed herein shall be
interpreted as illustrative only but not as limitative of the
principle and scope of the present disclosure. It should be
understood that the scope of the present disclosure shall be
defined by the appended Claims and all of their equivalents fall
within the scope of the present disclosure.
* * * * *