LIQUID CRYSTAL DISPLAY DEVICE AND DRIVING METHOD THEREOF

• US 20090289878A1
• Filed: 07/06/2008
• Published: 11/26/2009
• Est. Priority Date: 05/22/2008
• Status: Abandoned Application

• Current Assignee: AU Optronics Corporation
• Original Assignee: AU Optronics Corporation
• Inventors: Chen, Chung-Chun
• Application Number:
  US12/168,149
• Publication Number:
  US 20090289878A1
• Time in Patent Office: Days
• US Class Current: 345/87
• CPC Class Codes: G09G 2310/0297 Special arrangements with multiplexing or demultiplexing of display data in the drivers for data electrodes, in a pre-processing circuitry delivering display data to said drivers or in the matrix panel, e.g. multiplexing plural data signals to one D/A converter or demultiplexing the D/A converter output to multiple columns
• CPC Class Codes: G09G 3/3614 Control of polarity reversal in general
• CPC Class Codes: G09G 3/3655 Details of drivers for counter electrodes, e.g. common electrodes for pixel capacitors or supplementary storage capacitors
• CPC Class Codes: G09G 3/3688 suitable for active matrices only

Abstract

An LCD device and driving method thereof are disclosed. The LCD device includes a source driver, a controller, a voltage generator, a plurality of data lines, a plurality of pixels, and a plurality of demultiplexer modules. The controller provides two sets of control signals. The voltage generator provides an AC common voltage. Each demultiplexer module includes two demultiplexers. The first demultiplexer distributes data signals received from the source driver into a set of data lines based on the first set of control signals. The second demultiplexer distributes data signals received from the source driver into another set of data lines based on the second set of control signals. The driving method is utilized for writing a plurality of low-voltage data signals having different polarities into a plurality of pixels based on different common voltages during different intervals of a frame period.

Claims

1. A liquid crystal display device comprising:

a source driver for generating a plurality of data signals, the source driver comprising a plurality of output ports for outputting the data signals;

a gate driver for generating a plurality of gate signals;

a plurality of data lines, the data lines comprising a plurality of first data lines and a plurality of second data lines;

a plurality of gate lines, each of the gate lines being coupled to the gate driver for receiving a corresponding gate signal;

a control circuit for generating a plurality of first control signals and a plurality of second control signals; and

a plurality of demultiplexer modules, each of the demultiplexer modules comprising;

a first demultiplexer coupled to the control circuit, the source driver and the first data lines for distributing a first data signal of the data signals to the first data lines based on the first control signals; and

a second demultiplexer coupled to the control circuit, the source driver and the second data lines for distributing a second data signal of the data signals to the second data lines based on the second control signals.

2. The liquid crystal display device of claim 1, wherein the first demultiplexer comprises a plurality of switches, each of the switches comprises:

a first end coupled to a corresponding output port of the output ports of the source driver;

a second end coupled to a corresponding data line of the first data lines; and

a control end coupled to the control circuit for receiving a corresponding control signal of the first control signals, wherein the switch controls a signal connection between the first and second ends of the switch based on the corresponding control signal furnished to the control end of the switch;

wherein the switches are thin film transistors or MOS field effect transistors.

3. The liquid crystal display device of claim 1, wherein the second demultiplexer comprises a plurality of switches, each of the switches comprises:

a first end coupled to a corresponding output port of the output ports of the source driver;

a second end coupled to a corresponding data line of the second data lines; and

a control end coupled to the control circuit for receiving a corresponding control signal of the second control signals, wherein the switch controls a signal connection between the first end and the second end of the switch based on the corresponding control signal furnished to the control end of the switch;

wherein the switches are thin film transistors or MOS field effect transistors.

4. The liquid crystal display device of claim 1, further comprising:

a plurality of storage units, each of the storage units comprising;

a first end coupled to a corresponding data line of the data lines; and

a second end for receiving a common voltage.

5. The liquid crystal display device of claim 4, further comprising:

a plurality of common lines, each of the common lines coupled to a plurality of corresponding storage units of the storage units; and

a voltage generator coupled to the common lines for providing the common voltage.

6. A driving method for use in an LCD device, comprising:

setting a first gate signal to be an enabled signal during a first interval;

setting a common voltage to be a first voltage during a first sub-interval of the first interval; and

setting the common voltage to be a second voltage during a second sub-interval of the first interval.

7. The driving method of claim 6, further comprising:

setting the first gate signal to be a disabled signal during a second interval;

setting the common voltage to be the second voltage during a first sub-interval of the second interval; and

setting the common voltage to be the first voltage during a second sub-interval of the second interval.

8. The driving method of claim 6, wherein the first interval is corresponding to a line time.

9. A driving method for use in an LCD device, comprising:

setting a first gate signal to be an enabled signal during a first interval;

setting a common voltage to be a first voltage and writing a first set of data signals with a first polarity sequentially into a first set of storage units of the LCD device based on the enabled first gate signal during a first set of sub-intervals of the first interval; and

setting the common voltage to be a second voltage and writing a second set of data signals with a second polarity sequentially into a second set of storage units of the LCD device based on the enabled first gate signal during a second set of sub-intervals of the first interval;

wherein the first voltage is different from the second voltage, the first set of sub-intervals and the second set of sub-intervals are not overlapped, and the first polarity is opposite to the second polarity.

10. The driving method of claim 9, wherein:

setting the common voltage to be the first voltage and writing the first set of data signals with the first polarity sequentially into the first set of storage units of the LCD device based on the enabled first gate signal during the first set of sub-intervals of the first interval comprises;

setting the common voltage to be the first voltage and writing a first data signal with the first polarity into a first storage unit of the LCD device based on the enabled first gate signal during a first sub-interval of the first interval;

setting the common voltage to be the first voltage and writing a second data signal with the first polarity into a second storage unit of the LCD device based on the enabled first gate signal during a second sub-interval of the first interval; and

setting the common voltage to be the first voltage and writing a third data signal with the first polarity into a third storage unit of the LCD device based on the enabled first gate signal during a third sub-interval of the first interval; and

setting the common voltage to be the second voltage and writing the second set of data signals with the second polarity sequentially into the second set of storage units of the LCD device based on the enabled first gate signal during the second set of sub-intervals of the first interval comprises;

setting the common voltage to be the second voltage and writing a fourth data signal with the second polarity into a fourth storage unit of the LCD device based on the enabled first gate signal during a fourth sub-interval of the first interval;

setting the common voltage to be the second voltage and writing a fifth data signal with the second polarity into a fifth storage unit of the LCD device based on the enabled first gate signal during a fifth sub-interval of the first interval; and

setting the common voltage to be the second voltage and writing a sixth data signal with the second polarity into a sixth storage unit of the LCD device based on the enabled first gate signal during a sixth sub-interval of the first interval;

wherein the first, second and third sub-intervals are not overlapped between each other, and the fourth, fifth and sixth sub-intervals are not overlapped between each other.

11. The driving method of claim 10, wherein:

writing the first data signal with the first polarity into the first storage unit of the LCD device is writing the first data signal with the first polarity into the first storage unit of the LCD device via a first demultiplexer of the LCD device;

writing the second data signal with the first polarity into the second storage unit of the LCD device is writing the second data signal with the first polarity into the second storage unit of the LCD device via the first demultiplexer;

writing the third data signal with the first polarity into the third storage unit of the LCD device is writing the third data signal with the first polarity into the third storage unit of the LCD device via the first demultiplexer;

writing the fourth data signal with the second polarity into the fourth storage unit of the LCD device is writing the fourth data signal with the second polarity into the fourth storage unit of the LCD device via a second demultiplexer of the LCD device;

writing the fifth data signal with the second polarity into the fifth storage unit of the LCD device is writing the fifth data signal with the second polarity into the fifth storage unit of the LCD device via the second demultiplexer; and

writing the sixth data signal with the second polarity into the sixth storage unit of the LCD device is writing the sixth data signal with the second polarity into the sixth storage unit of the LCD device via the second demultiplexer.

12. The driving method of claim 10, wherein:

setting the common voltage to be the first voltage and writing the first data signal with the first polarity into the first storage unit of the LCD device based on the enabled first gate signal is setting the common voltage to be a low voltage and writing the first data signal with positive polarity into the first storage unit of the LCD device based on the enabled first gate signal;

setting the common voltage to be the first voltage and writing the second data signal with the first polarity into the second storage unit of the LCD device based on the enabled first gate signal is setting the common voltage to be the low voltage and writing the second data signal with positive polarity into the second storage unit of the LCD device based on the enabled first gate signal;

setting the common voltage to be the first voltage and writing the third data signal with the first polarity into the third storage unit of the LCD device based on the enabled first gate signal is setting the common voltage to be the low voltage and writing the third data signal with positive polarity into the third storage unit of the LCD device based on the enabled first gate signal;

setting the common voltage to be the second voltage and writing the fourth data signal with the second polarity into the fourth storage unit of the LCD device based on the enabled first gate signal is setting the common voltage to be a high voltage and writing the fourth data signal with negative polarity into the fourth storage unit of the LCD device based on the enabled first gate signal;

setting the common voltage to be the second voltage and writing the fifth data signal with the second polarity into the fifth storage unit of the LCD device based on the enabled first gate signal is setting the common voltage to be the high voltage and writing the fifth data signal with negative polarity into the fifth storage unit of the LCD device based on the enabled first gate signal; and

setting the common voltage to be the second voltage and writing the sixth data signal with the second polarity into the sixth storage unit of the LCD device based on the enabled first gate signal is setting the common voltage to be the high voltage and writing the sixth data signal with negative polarity into the sixth storage unit of the LCD device based on the enabled first gate signal.

13. The driving method of claim 10, further comprising:

setting a second gate signal to be an enabled signal during a second interval;

setting the common voltage to be the second voltage and writing a seventh data signal with the second polarity into a seventh storage unit of the LCD device based on the enabled second gate signal during a first sub-interval of the second interval;

setting the common voltage to be the second voltage and writing an eighth data signal with the second polarity into an eighth storage unit of the LCD device based on the enabled second gate signal during a second sub-interval of the second interval; and

setting the common voltage to be the second voltage and writing a ninth data signal with the second polarity into a ninth storage unit of the LCD device based on the enabled second gate signal during a third sub-interval of the second interval;

setting the common voltage to be the first voltage and writing a tenth data signal with the first polarity into a tenth storage unit of the LCD device based on the enabled second gate signal during a fourth sub-interval of the second interval;

setting the common voltage to be the first voltage and writing an eleventh data signal with the first polarity into an eleventh storage unit of the LCD device based on the enabled second gate signal during a fifth sub-interval of the second interval; and

setting the common voltage to be the first voltage and writing a twelfth data signal with the first polarity into a twelfth storage unit of the LCD device based on the enabled second gate signal during a sixth sub-interval of the second interval;

wherein the first interval and the second interval are not overlapped, and the first through sixth sub-intervals of the second interval are not overlapped between each other.

14. The driving method of claim 13, wherein:

setting the first gate signal to be the enabled signal during the first interval is furnishing the first gate signal having a high voltage level to a first gate line during the first interval; and

setting the second gate signal to be the enabled signal during the second interval is furnishing the second gate signal having a high voltage level to a second gate line adjacent to the first gate line during the second interval.

15. The driving method of claim 14, wherein:

the first through sixth storage units are coupled to the first gate line;

the seventh through twelfth storage units are coupled to the second gate line;

the first, second and third storage units are corresponding to a first pixel unit;

the fourth, fifth and sixth storage units are corresponding to a second pixel unit adjacent to the first pixel unit;

the seventh, eighth and ninth storage units are corresponding to a third pixel unit adjacent to the first pixel unit; and

the tenth, eleventh and twelfth storage units are corresponding to a fourth pixel unit adjacent to the second and third pixel units.

16. The driving method of claim 13, wherein:

writing the seventh data signal with the second polarity into the seventh storage unit of the LCD device is writing the seventh data signal with the second polarity into the seventh storage unit of the LCD device via a first demultiplexer of the LCD device;

writing the eighth data signal with the second polarity into the eighth storage unit of the LCD device is writing the eighth data signal with the second polarity into the eighth storage unit of the LCD device via the first demultiplexer;

writing the ninth data signal with the second polarity into the ninth storage unit of the LCD device is writing the ninth data signal with the second polarity into the ninth storage unit of the LCD device via the first demultiplexer;

writing the tenth data signal with the first polarity into the tenth storage unit of the LCD device is writing the tenth data signal with the first polarity into the tenth storage unit of the LCD device via a second demultiplexer of the LCD device;

writing the eleventh data signal with the first polarity into the eleventh storage unit of the LCD device is writing the eleventh data signal with the first polarity into the eleventh storage unit of the LCD device via the second demultiplexer; and

writing the twelfth data signal with the first polarity into the twelfth storage unit of the LCD device is writing the twelfth data signal with the first polarity into the twelfth storage unit of the LCD device via the second demultiplexer.

17. The driving method of claim 13, wherein:

setting the common voltage to be the second voltage and writing the seventh data signal with the second polarity into the seventh storage unit of the LCD device based on the enabled second gate signal is setting the common voltage to be a high voltage and writing the seventh data signal with negative polarity into the seventh storage unit of the LCD device based on the enabled second gate signal;

setting the common voltage to be the second voltage and writing the eighth data signal with the second polarity into the eighth storage unit of the LCD device based on the enabled second gate signal is setting the common voltage to be the high voltage and writing the eighth data signal with negative polarity into the eighth storage unit of the LCD device based on the enabled second gate signal;

setting the common voltage to be the second voltage and writing the ninth data signal with the second polarity into the ninth storage unit of the LCD device based on the enabled second gate signal is setting the common voltage to be the high voltage and writing the ninth data signal with negative polarity into the ninth storage unit of the LCD device based on the enabled second gate signal;

setting the common voltage to be the first voltage and writing the tenth data signal with the first polarity into the tenth storage unit of the LCD device based on the enabled second gate signal is setting the common voltage to be a low voltage and writing the tenth data signal with positive polarity into the tenth storage unit of the LCD device based on the enabled second gate signal;

setting the common voltage to be the first voltage and writing the eleventh data signal with the first polarity into the eleventh storage unit of the LCD device based on the enabled second gate signal is setting the common voltage to be the low voltage and writing the eleventh data signal with positive polarity into the eleventh storage unit of the LCD device based on the enabled second gate signal; and

setting the common voltage to be the first voltage and writing the twelfth data signal with the first polarity into the twelfth storage unit of the LCD device based on the enabled second gate signal is setting the common voltage to be the low voltage and writing the twelfth data signal with positive polarity into the twelfth storage unit of the LCD device based on the enabled second gate signal.

18. The driving method of claim 9, wherein:

setting the common voltage to be the first voltage and writing the first set of data signals with the first polarity sequentially into the first set of storage units of the LCD device based on the enabled first gate signal during the first set of sub-intervals of the first interval comprises;

setting the common voltage to be the first voltage and writing a first data signal with the first polarity into a first storage unit of the LCD device based on the enabled first gate signal during a first sub-interval of the first interval;

setting the common voltage to be the first voltage and writing a third data signal with the first polarity into a third storage unit of the LCD device based on the enabled first gate signal during a second sub-interval of the first interval; and

setting the common voltage to be the first voltage and writing a fifth data signal with the first polarity into a fifth storage unit of the LCD device based on the enabled first gate signal during a third sub-interval of the first interval; and

setting the common voltage to be the second voltage and writing the second set of data signals with the second polarity sequentially into the second set of storage units of the LCD device based on the enabled first gate signal during the second set of sub-intervals of the first interval comprises;

setting the common voltage to be the second voltage and writing a second data signal with the second polarity into a second storage unit of the LCD device based on the enabled first gate signal during a fourth sub-interval of the first interval;

setting the common voltage to be the second voltage and writing a fourth data signal with the second polarity into a fourth storage unit of the LCD device based on the enabled first gate signal during a fifth sub-interval of the first interval; and

setting the common voltage to be the second voltage and writing a sixth data signal with the second polarity into a sixth storage unit of the LCD device based on the enabled first gate signal during a sixth sub-interval of the first interval;

wherein the first, second and third sub-intervals are not overlapped between each other, and the fourth, fifth and sixth sub-intervals are not overlapped between each other.

19. The driving method of claim 18, wherein:

writing the first data signal with the first polarity into the first storage unit of the LCD device is writing the first data signal with the first polarity into the first storage unit of the LCD device via a first demultiplexer of the LCD device;

writing the third data signal with the first polarity into the third storage unit of the LCD device is writing the third data signal with the first polarity into the third storage unit of the LCD device via the first demultiplexer;

writing the fifth data signal with the first polarity into the fifth storage unit of the LCD device is writing the fifth data signal with the first polarity into the fifth storage unit of the LCD device via a second demultiplexer of the LCD device;

writing the second data signal with the second polarity into the second storage unit of the LCD device is writing the second data signal with the second polarity into the second storage unit of the LCD device via the first demultiplexer;

writing the fourth data signal with the second polarity into the fourth storage unit of the LCD device is writing the fourth data signal with the second polarity into the fourth storage unit of the LCD device via the second demultiplexer; and

writing the sixth data signal with the second polarity into the sixth storage unit of the LCD device is writing the sixth data signal with the second polarity into the sixth storage unit of the LCD device via the second demultiplexer.

20. The driving method of claim 18, wherein:

setting the common voltage to be the first voltage and writing the first data signal with the first polarity into the first storage unit of the LCD device based on the enabled first gate signal is setting the common voltage to be a low voltage and writing the first data signal with positive polarity into the first storage unit of the LCD device based on the enabled first gate signal;

setting the common voltage to be the first voltage and writing the third data signal with the first polarity into the third storage unit of the LCD device based on the enabled first gate signal is setting the common voltage to be the low voltage and writing the third data signal with positive polarity into the third storage unit of the LCD device based on the enabled first gate signal;

setting the common voltage to be the first voltage and writing the fifth data signal with the first polarity into the fifth storage unit of the LCD device based on the enabled first gate signal is setting the common voltage to be the low voltage and writing the fifth data signal with positive polarity into the fifth storage unit of the LCD device based on the enabled first gate signal;

setting the common voltage to be the second voltage and writing the second data signal with the second polarity into the second storage unit of the LCD device based on the enabled first gate signal is setting the common voltage to be a high voltage and writing the second data signal with negative polarity into the second storage unit of the LCD device based on the enabled first gate signal;

setting the common voltage to be the second voltage and writing the fourth data signal with the second polarity into the fourth storage unit of the LCD device based on the enabled first gate signal is setting the common voltage to be the high voltage and writing the fourth data signal with negative polarity into the fourth storage unit of the LCD device based on the enabled first gate signal; and

setting the common voltage to be the second voltage and writing the sixth data signal with the second polarity into the sixth storage unit of the LCD device based on the enabled first gate signal is setting the common voltage to be the high voltage and writing the sixth data signal with negative polarity into the sixth storage unit of the LCD device based on the enabled first gate signal.

21. The driving method of claim 18, further comprising:

setting a second gate signal to be an enabled signal during a second interval;

setting the common voltage to be the second voltage and writing a seventh data signal with the second polarity into a seventh storage unit of the LCD device based on the enabled second gate signal during a first sub-interval of the second interval;

setting the common voltage to be the second voltage and writing a ninth data signal with the second polarity into a ninth storage unit of the LCD device based on the enabled second gate signal during a second sub-interval of the second interval; and

setting the common voltage to be the second voltage and writing an eleventh data signal with the second polarity into an eleventh storage unit of the LCD device based on the enabled second gate signal during a third sub-interval of the second interval;

setting the common voltage to be the first voltage and writing an eighth data signal with the first polarity into an eighth storage unit of the LCD device based on the enabled second gate signal during a fourth sub-interval of the second interval;

setting the common voltage to be the first voltage and writing a tenth data signal with the first polarity into a tenth storage unit of the LCD device based on the enabled second gate signal during a fifth sub-interval of the second interval; and

setting the common voltage to be the first voltage and writing a twelfth data signal with the first polarity into a twelfth storage unit of the LCD device based on the enabled second gate signal during a sixth sub-interval of the second interval;

wherein the first interval and the second interval are not overlapped, and the first through sixth sub-intervals of the second interval are not overlapped between each other.

22. The driving method of claim 21, wherein:

setting the first gate signal to be the enabled signal during the first interval is furnishing the first gate signal having a high voltage level to a first gate line during the first interval; and

setting the second gate signal to be the enabled signal during the second interval is furnishing the second gate signal having a high voltage level to a second gate line adjacent to the first gate line during the second interval.

23. The driving method of claim 22, wherein:

the first through sixth storage units are coupled to the first gate line;

the seventh through twelfth storage units are coupled to the second gate line;

the first, second and third storage units are corresponding to a first pixel unit;

the fourth, fifth and sixth storage units are corresponding to a second pixel unit adjacent to the first pixel unit;

the seventh, eighth and ninth storage units are corresponding to a third pixel unit adjacent to the first pixel unit; and

the tenth, eleventh and twelfth storage units are corresponding to a fourth pixel unit adjacent to the second and third pixel units.

24. The driving method of claim 21, wherein:

writing the seventh data signal with the second polarity into the seventh storage unit of the LCD device is writing the seventh data signal with the second polarity into the seventh storage unit of the LCD device via a first demultiplexer of the LCD device;

writing the ninth data signal with the second polarity into the ninth storage unit of the LCD device is writing the ninth data signal with the second polarity into the ninth storage unit of the LCD device via the first demultiplexer;

writing the eleventh data signal with the second polarity into the eleventh storage unit of the LCD device is writing the eleventh data signal with the second polarity into the eleventh storage unit of the LCD device via a second demultiplexer of the LCD device;

writing the eighth data signal with the first polarity into the eighth storage unit of the LCD device is writing the eighth data signal with the first polarity into the eighth storage unit of the LCD device via the first demultiplexer of the LCD device;

writing the tenth data signal with the first polarity into the tenth storage unit of the LCD device is writing the tenth data signal with the first polarity into the tenth storage unit of the LCD device via the second demultiplexer; and

writing the twelfth data signal with the first polarity into the twelfth storage unit of the LCD device is writing the twelfth data signal with the first polarity into the twelfth storage unit of the LCD device via the second demultiplexer.

25. The driving method of claim 21, wherein:

setting the common voltage to be the second voltage and writing the seventh data signal with the second polarity into the seventh storage unit of the LCD device based on the enabled second gate signal is setting the common voltage to be a high voltage and writing the seventh data signal with negative polarity into the seventh storage unit of the LCD device based on the enabled second gate signal;

setting the common voltage to be the second voltage and writing the ninth data signal with the second polarity into the ninth storage unit of the LCD device based on the enabled second gate signal is setting the common voltage to be the high voltage and writing the ninth data signal with negative polarity into the ninth storage unit of the LCD device based on the enabled second gate signal;

setting the common voltage to be the second voltage and writing the eleventh data signal with the second polarity into the eleventh storage unit of the LCD device based on the enabled second gate signal is setting the common voltage to be the high voltage and writing the eleventh data signal with negative polarity into the eleventh storage unit of the LCD device based on the enabled second gate signal;

setting the common voltage to be the first voltage and writing the eighth data signal with the first polarity into the eighth storage unit of the LCD device based on the enabled second gate signal is setting the common voltage to be a low voltage and writing the eighth data signal with positive polarity into the eighth storage unit of the LCD device based on the enabled second gate signal;

setting the common voltage to be the first voltage and writing the tenth data signal with the first polarity into the tenth storage unit of the LCD device based on the enabled second gate signal is setting the common voltage to be the low voltage and writing the tenth data signal with positive polarity into the tenth storage unit of the LCD device based on the enabled second gate signal; and

setting the common voltage to be the first voltage and writing the twelfth data signal with the first polarity into the twelfth storage unit of the LCD device based on the enabled second gate signal is setting the common voltage to be the low voltage and writing the twelfth data signal with positive polarity into the twelfth storage unit of the LCD device based on the enabled second gate signal.