Display device and driving method thereof in which bias current of data driver is controlled based on image pattern information

• US 9,978,332 B2
• Filed: 07/31/2014
• Issued: 05/22/2018
• Est. Priority Date: 02/11/2014
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Lee, Yong Soon, Kang, Moon Shik, Park, Jin Ho
• Primary Examiner(s): NOKHAM, JAMES S
• Application Number:
  US14/448,558
• Publication Number:
  US 20150228241A1
• Time in Patent Office: 1,391 Days
• Field of Search: 341122, 341145, 345 89, 345211, 345213
• CPC Class Codes: G09G 2310/0248 Precharge or discharge of column electrodes before or after applying exact column voltages
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: G09G 3/3688 suitable for active matrices only

Abstract

A display device including: a display panel including pixels and data lines; a data driver configured to apply data voltages to the data lines; an image pattern determiner configured to determine an image pattern based on an input image signal and to generate image pattern information; and a bias current control signal generator configured to generate a bias current control signal for determining a magnitude of a bias current of the data driver based on the image pattern information.

Claims

1. A display device comprising:

a display panel comprising a plurality of rows of pixels and data lines;

an image pattern determiner configured to receive an input image signal of a frame, determine a type of an image pattern to be displayed on the display panel for the entire plurality of rows of pixels based on an the input image signal and generate an image pattern information about the type of the image pattern for the frame, the type of the image pattern being dependent on a degree of a dynamic power consumption;

a data driver configured to receive an output image signal and generate data voltages to be supplied to the data lines based on the output image signal, the data driver comprising a digital to analog converter for converting the output image signal to the data voltages; and

a bias current control signal generator configured to receive the image pattern information and generate a bias current control signal for controlling a magnitude of a bias current of the data driver for the frame based on the image pattern information, wherein;

the bias current control signal generator comprises a plurality of switches each corresponding to a different parameter from each other among a plurality of parameters; and

one of the switches is turned on according to the image pattern information to select a parameter of the plurality of parameters, which is output as the bias current control signal.

2. The display device of claim 1, wherein the data driver comprises a bias unit for generating a bias current based on the bias current control signal.

3. The display device of claim 2, wherein the data driver comprises an amplifier configured to receive a voltage according to the bias current.

4. The display device of claim 3, wherein a minimum value of the parameters represents the image pattern of a gray-based image pattern.

5. The display device of claim 4, wherein a maximum value of the parameters represents the image pattern of a vertical stripe pattern in a row unit.

6. The display device of claim 5, wherein pixels of one pixel column of the pixels are alternatively connected to two adjacent data lines.

7. The display device of claim 6, wherein, during one frame:

a polarity of the data voltages applied to the data lines is constant; and

polarities of the data voltages applied to adjacent data lines are opposite to each other.

8. The display device of claim 2, further comprising a signal controller configured to control the data driver,

wherein the signal controller comprises the image pattern determiner and the bias current control signal generator.

9. The display device of claim 2, further comprising a signal controller configured to control the data driver,

wherein the signal controller comprises the image pattern determiner, and the data driver comprises the bias current control signal generator.

10. A display device comprising:

a display panel comprising pixels and data lines;

an image pattern determiner configured to receive an input image signal of a frame, determine a type of an image pattern to be displayed on the display panel for the entire pixels based on the input image signal and generate an image pattern information about the type of the image pattern for the frame, the type of the image pattern being dependent on a degree of a dynamic power consumption;

a data driver configured to receive an output image signal and generate data voltages to be supplied to the data lines, the data driver comprising a digital to analog converter for converting the output image signal to the data voltages; and

a bias current control signal generator configured to receive the image pattern information and generate a bias current control signal for controlling a magnitude of a bias current of the data driver for the frame based on the image pattern information, wherein;

the bias current control signal generator comprises a plurality of switches each corresponding to a different parameter from each other among a plurality of parameters; and

one of the switches is turned on according to the image pattern information to select a parameter of the plurality of parameters, which is output as the bias current control signal;

the data driver comprises driving blocks, the driving blocks comprising a bias unit configured to receive the image pattern information and generate a bias current having a magnitude that is controlled according to image pattern information; and

at least one of the driving blocks, except for the bias unit, is stopped during a first period of one frame while the bias unit does not stop during the first period.

11. The display device of claim 10, wherein the first period includes a vertical blank period.

12. A method of driving a display device comprising a display panel comprising a plurality of rows of pixels and data lines, an image pattern determiner, a bias current control signal generator, and a data driver, the method comprising:

determining a type of an image pattern to be displayed on the display panel for the entire plurality of rows of pixels based on an input image signal of a frame and generating an image pattern information about the type of the image pattern for the frame, by the image pattern determiner, the type of the image pattern being dependent on a degree of a dynamic power consumption;

turning on, according to the image pattern information, at least one of a plurality of switches each corresponding to a different parameter from each other among a plurality of parameters of the bias current control signal generator, to select a parameter of the plurality of parameters, which is output as a bias current control signal for controlling a magnitude of a bias current of the data driver, by the bias current control signal generator;

generating a bias current for the frame based on the bias current control signal, by the data driver;

generating data voltages based on the input image signal, by the data driver;

and applying the data voltages to the data lines.

13. The driving method of claim 12, wherein a minimum value of the parameters represents the image pattern of a gray-based image pattern.

14. The driving method of claim 13, wherein a maximum value of the parameters represents the image pattern of a vertical stripe pattern in a row unit.

15. The driving method of claim 14, wherein:

a polarity of the data voltage applied to one data line during one frame is constant; and

polarities of the data voltages applied to adjacent data lines are opposite to each other.

16. A method of driving a display device comprising a display panel comprising pixels and data lines, an image pattern determiner, and a data driver comprising driving blocks, the driving blocks comprising a bias unit, the method comprising:

determining a type of an image pattern to be displayed on the display panel for the entire pixels based on an input image signal of a frame and generating an image pattern information about the type of the image pattern for the frame, by the image pattern determiner, the type of the image pattern being dependent on a degree of a dynamic power consumption;

generating data voltages based on the input image signal, by the data driver; and

a bias current control signal generator configured to receive the image pattern information and generate a bias current control signal for controlling a magnitude of a bias current of the data driver for the frame based on the image pattern information, wherein;

the bias current control signal generator comprises a plurality of switches each corresponding to a different parameter from each other among a plurality of parameters; and

one of the switches is turned on according to the image pattern information to select a parameter of the plurality of parameters, which is output as the bias current control signal;

receiving the image pattern information and generating a bias current having a magnitude that is controlled according to the image pattern information; and

stopping at least one of the driving blocks, except for the bias unit, during a first period of one frame while the bias unit does not stop during the first period.

17. The driving method of claim 16, wherein the first period comprises a vertical blank period.