Low-Power Driving Display Device and Driving Method of Same

Patent metadata

Field	Value
Publication number	US-2022208123-A1
Application number	US-202117545964-A
Country	US
Kind code	A1
Filing date	Dec 8, 2021
Priority date	Dec 28, 2020
Publication date	Jun 30, 2022
Grant date	—

Abstract

A lower-power driving display device and a driving method. The driving method of the display device includes dividing the plurality of output buffers of the data driver into a plurality of output buffer groups, each of the plurality of output buffers being configured to apply the data voltage to each of the plurality of data lines connected with the display panel, and determining the magnitude of a bias current supplied to an output buffer on the basis of a pattern of a data voltage output by the output buffer which belongs to each of the plurality of divided output buffer groups.

First claim

What is claimed is:

1 . A display device comprising:
a display panel having a plurality of pixels disposed in a matrix form thereon; a timing controller configured to process an image signal and a control signal received from an outside and to generate data, a data drive control signal, and a gate drive control signal for outputting the image signal to the display panel; and a data driver comprising output buffers configured to output a corresponding data voltage to each of a plurality of data lines of the display panel, wherein the plurality of data lines are divided into a plurality of data line groups, respectively, and the data driver supplies a bias current having a different magnitude for each of the data line groups to each of the output buffers which drive data lines which belong to the plurality of data line groups, respectively.

2 . The display device of claim 1 , wherein based on pattern recognition results on the data which are required to be output to the data lines which belong to the plurality of data line groups, respectively, the bias currents supplied to the output buffers corresponding to the plurality of data line groups, respectively, have different magnitudes.

3 . The display device of claim 2 , wherein an applicable maximum bias current is supplied to a data line group comprising at least one data line to which an outputting data voltage having a toggle pattern is applied.

4 . The display device of claim 3 , wherein a corresponding 1-bit bias control signal is provided for each of the plurality of data line groups,
wherein the bias control signal is generated such that a first logic value is set for a bit corresponding to the data line group which receives the applicable maximum bias current, and a second logic value is set for a bit corresponding to each of remaining data line groups, the bias control signal being applied to the data driver.

5 . The display device of claim 4 , wherein on a basis of the bias control signal, the data driver supplies the applicable maximum bias current to a first output buffer for the data line group corresponding to the bit for which the first logic value is set, and supplies a bias current to a first output buffer for the data line group corresponding to the bit for which the second logic value is set, the bias current being obtained by subtracting a magnitude of a preset current from the applicable maximum bias current supplied to the first output buffer for the adjacent data line group.

6 . The display device of claim 5 , wherein the data driver is provided with a bias part for each of the plurality of data line groups,
wherein the bias part comprises: a plurality of constant current sources having the same magnitudes, and a plurality of switches for connecting each of the plurality of constant current sources to the first output buffer for the data line group, wherein the data driver controls the plurality of switches on a basis of a magnitude of a current to be supplied to a first output buffer for each of the plurality of data line groups.

7 . The display device of claim 5 , wherein in order to perform an interpolation for preventing a visibility defect at a boundary between each of the plurality of data line groups, a data line group which is located at a position adjacent to the boundary between each of the plurality of data line groups and has data lines preset in number is set to be changed in an even-numbered frame and an odd-numbered frame.

8 . The display device of claim 7 , wherein when bias currents supplied to first output buffers for data line groups at opposite sides of the boundary have the same magnitudes, the data line group to which the data lines belong is set not to be changed in the even-numbered frame and the odd-numbered frame.

9 . The display device of claim 1 , wherein the plurality of pixels are divided into a plurality of pixel groups on a basis of a distance between each of the pixels and the data driver, and
the data driver supplies a bias current having a different magnitude to a first output buffer for each of the plurality of pixel groups such that time which a data voltage output to each of the data lines connected to the plurality of pixel groups takes to reach a preset voltage (a settled value) in a last pixel of an associated pixel group is the same in each of the plurality of pixel groups.

10 . The display device of claim 9 , wherein in order to perform an interpolation for preventing a visibility defect at a boundary between each of the plurality of pixel groups, a pixel group which is located at a position adjacent to the boundary between each of the plurality of pixel groups and has pixels preset in number is set to be changed in an even-numbered frame and an odd-numbered frame.

11 . The display device of claim 10 , wherein in the odd-numbered frame, settings of the plurality of pixel groups are maintained, and
in the even-numbered frame, pixels which each of the plurality of pixel groups comprises are changed such that each of the plurality of set pixel groups is moved by a preset number to a first side toward the data driver or to a second side away from the data driver.

12 . The display device of claim 10 , wherein in the odd-numbered frame, pixels which each of the plurality of pixel groups comprises are changed such that each of the plurality of set pixel groups is moved by a preset number to a side toward the data driver,
in the even-numbered frame, pixels which each of the plurality of pixel groups comprises are changed such that each of the plurality of set pixel groups is moved by a preset number to a side far from the data driver.

13 . The display device of claim 9 , wherein in order to perform a plurality of interpolations for preventing a visibility defect at a boundary between each of the plurality of pixel groups, an interpolation area is set for performing an interpolation at a surrounding area of the boundary, the interpolation area is divided into n sub-groups, and a frame set is configured by n+1 frames greater by 1 than the number of the sub-groups, so a data voltage applied to a pixel which belongs to each of the n sub-groups is changed from a first pixel group toward a second pixel group adjacent thereto in frames different from each other inside the frame set.

14 . The display device of claim 1 , wherein the display panel further comprises touch electrodes, and
the display device further comprises a touch driver configured to supply a touch drive signal voltage to each of the touch electrodes of the display panel, wherein the plurality of touch electrodes is divided into a plurality of touch electrode groups on a basis of a distance between each of the touch electrodes and the touch driver, and the touch driver supplies a different touch drive signal voltage to each of the plurality of touch electrode groups such that the touch drive signal voltage supplied to each of the touch electrodes which are located in each of the plurality of touch electrode groups and are located at positions, respectively, farthest from the touch driver is the same.

15 . The display device of claim 1 , wherein among the plurality of data line groups, a magnitude of a bias current supplied to a first output buffer corresponding to a data line group comprising at least one data line to which a data voltage having a toggle pattern is applied is larger than a magnitude of a bias current supplied to a second output buffer corresponding to a data line group which does not comprise a data line to which a data voltage having a toggle pattern is applied.

16 . A driving

Assignees

• Lg Display Co Ltd

Inventors

• Kim Daehwan
• Kang Jeongho
• Park Yongjin

Classifications

• G09G2310/0291

  Details of output amplifiers or buffers arranged for use in a driving circuit · CPC title

• G06F3/0412

  Digitisers structurally integrated in a display · CPC title

• G09G2330/021

  Power management, e.g. power saving · CPC title

• G06F3/0416

  Control or interface arrangements specially adapted for digitisers · CPC title

• G06F3/04166

  Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving (Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184) · CPC title