TWI232427B - Driving method of driving circuit - Google Patents

Abstract

The present invention provides a driving method of LCD panel in which the driving pixel is formed by the data line connected to the data driver and the gate line connected to the gate driver. In the method of the present invention, a first gate driver is selected from at least two gate drivers based on the selection rule, and the first gate driver displays the image pattern corresponding to the portion of the driving voltage for a predetermined number rows sequentially from the gate line of the A row. Select the second gate driver based on the selection rule, and the second gate driver displays the image pattern corresponding to the portion of the driving voltage having a target value for a predetermined number rows simultaneously from the gate line of B row which is spaced apart with A row by predetermined distance, so that the pixels in the predetermined number of rows from the B row resumes to the target value.

Description

1232427 V. Description of the invention [Technical field to which the invention belongs] The present invention relates to a driving method of a driving circuit, and particularly to driving a liquid crystal panel with a fast gray-scale response time. [Prior art] It is well known that due to the relationship between the display characteristics of LCD displays, the grayscale response speed of LCD displays always has a certain bottleneck. When used as a personal computer monitor, the use of LCD monitors and CRT monitors will not be significantly different for users. However, when LCD TVs are used to watch TV programs, because the TV programs are almost entirely dynamic images, the problem of the grayscale response speed of LCDs has a certain bottleneck, which is the traditional LCD TV. Its display effect will be significantly worse than CRT TV. Traditionally, the plurality of pixels of the above-mentioned LCD are driven by a plurality of data drivers and a plurality of gate drivers included in a driving circuit. A pixel of the LCD panel is composed of a data line connected to the data driver and a gate line connected to the gate driver. In the following, the conventional LCD driving method is briefly described, and then the existing methods for improving the grayscale response speed are discussed. Please refer to Figures 1 A to 1 B. Figures 1 A to 1 B are conventional driving waveforms. When the vertical sync signal appears, a new daylight will

1232427 # Instructions (2),: 4 are displayed on the LCD panel one by one. First, as shown in Figure 1A, the STH signal will become active, indicating that the first to first pixel data of the first scan line will be sequentially input into the data driver. When the horizontal clock signal rises, the first pixel data will be shifted from left to right, and the next pixel data will be read in until the nth stroke. The above pixel data is digital data including R, G, and B. If the pixel data of the first row to the n-th row has been shifted, the data driver receives a rising signal as shown in Figure 1A, and the R of each pixel data in the same row The digital data of G, G and B are converted into corresponding driving voltages to the data lines in the LCD panel. At this time, as shown in Figure 1B, the vertical clock will rise, and the gate driving circuit will turn on the gate driving signal of the first line, so that the driving voltage driven by the data driving circuit on the data line is converted to the first of the LCD panel. After that, the other scanning lines will display the entire day signal on the panel in the same way. At present, many methods for improving the grayscale response speed of LCDs have been proposed, and one of them is called an analog pulse driving method (Ps e u d ο I m p u 1 s e D r i v e, P I D) is a more promising method. As the name implies, the PI D series uses analog pulse driving methods such as CRT to drive the LCD, making the LCD as close to the CRT display effect as possible. There are currently three known PID methods. Please refer to Figures 2A ~ 2C. Figures 2A ~ 2C are schematic diagrams of the conventional analog pulse driving method. As shown in Figure 2A, an image is played sequentially.

5. Description of the invention (3) Boxes 1, 2, 3, and 4 are composed. Between frames 1 and 2, picture. The first analog pulse driving method is to insert H 1 1, 12 and 1 3 separately for each frame by inserting it between the black and white assets 2 and 3 and between frames 3 and 4, respectively, and Corresponding to the first analog pulse drive mentioned above, the earth backlight sources 14 ~ 20 are all in the light-emitting state. The balance method is used to achieve the purpose of analog pulses, as shown in Figure 2B. — Today, 5, 6, and Framed by 7 / The first frame is played in sequence. Frames 1, 2, 3, 4 do n’t correspond to frames 2, 4, and R. An analog pulse driving method is to divide the state into the extinguished state, and to restore the individual points of time. Backlights 22, 24, and 26, sources 21, 23, 25, and the backlight of frames 1, 3, 5, 7, 9, and 6, and 7 maintain the original makeup 2 " light state, and frame 1, 2, 3, 4, 5 kinds of analog pulse driving methods. In other words, the blinking hibiscus in the second off state interacts with the backlight source to turn on and off, thereby achieving the purpose of simulating pulses. As shown in Figure 2C, -g you constitute. And the third kind of wedge: Play frame 1, 2, 3, and 4 pseudo-pulse driving methods in sequence, so that the r ^ picture = dynamic method combines the above two modes and the division between frames 3 and 4 ^^ Between 2 and between frames 2 and 3, and inserting an all-black data frame Η, 12 on the back, please 2 9 corresponds to the individual time points 2 t of frames U, 12 and 13; 4 V ': the annihilation state' while the others are on the frame 1 and Γ-ΛJ, the original 21, 23, 25, and 27 are light-emitting states. In other words, Ϊ Γ 二 ί ^ Ϊ The driving method is to use the backlight to interact with each other; the flashing mode of the off state is also shown in the picture frame, 2, 3, and 1232427. 5. Description of the invention (4) 4 each An all-black frame is inserted between them to achieve the purpose of simulating pulses. SUMMARY OF THE INVENTION The main object of the present invention is to provide a driving method of a driving circuit, and to drive a liquid crystal panel with a fast gray-scale response time.

Based on the above object, the present invention provides a driving method of a driving circuit. This driving method drives a liquid crystal panel by a plurality of data drivers and at least two gate drivers in the driving circuit. A pixel of the liquid crystal panel is composed of a data line connected by a data driver and a gate line connected by a gate driver. When the driving voltage corresponding to at least one column of pixels corresponding to the graphic image is input from the data line, the gate driver displays the graphic image on the liquid crystal panel in sequence by the gate driving signal input by the gate line.

Specifically, the driving method disclosed in the present invention firstly selects a first gate driver among at least two gate drivers based on a selection rule, and causes the first gate driver to sequentially display a predetermined number of rows from the gate lines of the A column. The graphic image of the part corresponding to the driving voltage. Then, also based on the selection rule, a second gate driver is selected from at least two gate drivers, and the second gate driver is simultaneously displayed from a predetermined number of gate lines from the Bth column at a predetermined distance from the Ath column. Predetermined target voltage drive voltage

Page 8 1232427 V. Description of the invention (5) The pixel number of the predetermined number of columns in column B is returned to the target value. After the relative screen data of the first brake driver has been displayed, the next brake drive circuit will then drive the relative daytime data. Similarly, after the pixels of the last column of the second gate driver have been returned to the target value, the next gate driver will then return the pixels of the predetermined number of columns to the target value in the same manner. As long as the number of intervals between columns A and B is selected in the design, when displaying the day surface, there will be no daytime display or return target value on the same gate drive. About the advantages and spirit of the present invention, the following can be achieved by The detailed description of the invention and the attached drawings are further understood. [Implementation method] Please refer to FIG. 3, which is a schematic diagram of a driving circuit of the present invention. As shown in Fig. 3, the driving circuit of the present invention drives the liquid crystal panel 34 by a plurality of data drivers 30 and gate drivers 32 and 33. When the resolution of the LCD panel 34 is 640X480, the number of pixels of the LCD panel 34 is 3 0 72 0 0 (64 0X48 0), and the data lines connected to the plurality of data drivers 30 are 6 4 0 Line, and the gate lines connected to the gate drivers 3 2 and 3 3 are 480 columns. It should be noted that the OE signals of the gate drivers 3 2 and 3 3 inputted in the driving circuit of the present invention are OE 1 and OE 2 respectively, and the 0 E signal is different from the 0 E signal input in the conventional driving circuit. Always on.

1232427 V. Description of the invention (6) The resolution of the LCD panel 34 is 640X48 0. In order to drive the LCD panel 34 smoothly, the gate drivers 3 2 and 3 3 need to allocate 4 8 0 gate wires connected to the LCD panel 34. Therefore, the number of fixed gate wires connected to the gate drivers 3 2 and 3 3 is 240 columns. In other words, the gate driver 32 is connected to the gate lines of the 1st to 240th columns, and the gate driver 33 is connected to the gate lines of the 241st to 480th columns. Therefore, when a graphic image is to be displayed on the LCD panel 34, during each frame time, the gate drivers 3 2 and 3 3 are sequentially displayed here by sequentially scanning 4 80 rows of gate lines. Graphic image in frame. In brief, the driving method of the present invention is based on the selection rule, selecting the gate driver 32 from the gate drivers 32 and 33 as the first gate driver, and the gate driver 33 as the second gate driver. And by using the first gate driver and the second gate driver, a scanning sequence of gate lines different from the conventional technique is performed, so as to drive the liquid crystal panel with a fast gray-scale response time. The following will describe how to generate the special scanning sequence of the present invention through OE 1 and OE 2, and how the selection rules select the first gate driver and the second gate driver. In the scanning sequence of the driving method of the present invention, first, a graphic image of a portion corresponding to a driving voltage of a predetermined number of columns is sequentially displayed from the gate lines of the A column by the first gate driver. Next, the second gate driver simultaneously displays a predetermined number of driving voltages having a target value from the gate lines of the Bth column spaced a predetermined distance from the Ath column, and returns the pixels from the predetermined number of pixels in the Bth column.

Page 10 1232427 V. Description of the invention (7) To the target value. Since the predetermined pitch is greater than or equal to the number of fixed lines, when the resolution of the liquid crystal panel 34 is 64 × 0 4 0 0, the predetermined pitch is greater than the number of fixed lines of 240. In other words, a part of the graphic image and a driving voltage having a target value are processed by different gate drivers such as the gate drivers 32 and 33. In order to modify the conventional driving circuit to display the graphic image of the part and the graphic represented by the driving voltage with the target value in a “sequential order”, such as a fixed number of lines of 2 to 40, , So that the gate drivers 3 2 and 3 3 can accept the control of the above 0E 1 and 0E 2 and display them in a "hop sequence" manner. Based on the above description, the rule system is selected. Shame, f material riot 3 α more enemies > avoid / drive. When the voltage is corresponding to a part of the graphic image, / then-is. .. The reversed J-shape is displayed on the liquid crystal panel 34. The gate driver 1 is the 5th gate driver. Mann is the driving voltage with a target value. The graph produced by the driving voltage is displayed on the LCD panel gate driver 33. This is the second gate drive. Figure C 4-A 4 Please refer to the figure 4 for the method between the French and the French. The road is U —1 ^ The first drive is issued as a copy and it is 1 The figure is C number 4 ~ column A is determined when 2 is 3 because it is away from Ma Mingfa in the display area. At the moment, Ma Zha in the follower area is the first place. Figure 4A shows 4. It is just as it is. It is the same as the one in the second place and the first place of the driving gate of the second slave. If the brake train is divided,

The number of lines of the gate is set in advance. ^ 9ΠΊ l ^ no The opening of the gate is 21, the 3 drive, the third is the L oit 4, the image is 0 ?, the shadow is 32, the distance is the same, and the column is the same.

Page 11 1232427 V. Description of the invention (8) / Press. Because the target voltage represents a / full-black graph, the number of columns in the graph rises to 1. The predetermined number of columns is 1. Therefore, the second gate driver displays the gate lines from the 3rd and 2nd columns simultaneously, and displays 1 column at the same time. Close to full black graphic 42.

As shown in FIG. 4B, the above scanning operation is repeated and sequentially scanned, and the first gate driver displays the column part of the graphic image 40 as the first column, and the predetermined interval is still 3 2 0, so by The second brake driver displays a nearly full black pattern 4 2 in the 3 3 1 column. When the gate driver 3 2 continues the above scanning operation to the last column of the gate line connected to the gate driver 3 2, that is, the column 3 2 0, the next line of the input graphic image 40 will be transformed into the gate driver 3 3 connected brake wires. Similarly, the next time the input near full black pattern 4 2 will be transformed into the gate line connected to the gate driver 32. In other words, the first gate driver will be transformed from the gate driver 32 to the gate driver 33, and the second gate driver will be transformed from the gate driver 33 to the gate driver 32. This is because, according to the selection rule, the first gate driver system is defined to input a sequence portion of the graphic image 40, and the second gate driver system is defined to input a pattern almost completely black 4 2.

As shown in FIG. 4C, the gate driver 3 3 of the first gate driver is inputted in the column 3 2 1 of the graphic image 4 0, and the gate driver 32 of the second gate driver is the same In the first column with a predetermined pitch of 3 2 0, a pattern 4 2 which is nearly completely black is input. Because before the input of the column of the graphic image 40 in the 3 21st column, the figure 321 in the 321st column, which is nearly black as shown in FIG. 4A, has been entered, so that the pixels in the 3 21st column have been input. The points have been restored to the driving voltage of the target value of the pattern 4 2 which is completely black in advance. So, as the first gate driver

Page 1212324 V. Description of the invention (9) After the brake driver 3 3 of the graphic image 4 0 is entered in the 3 21 column, the voltage change of each pixel point in the 321 column appears as The pulse shape of the CRT screen achieves the purpose of the invention, and drives the LCD panel 34 with a fast gray-scale response time. Hereinafter, a driving waveform diagram corresponding to the scanning sequence and driving method described above will be further described. Please refer to FIG. 5, which is a driving waveform diagram of the present invention. When the predetermined number of columns is 1, the first column is the first column, and the predetermined pitch is 3 2 0, as shown in FIG. 5, the order of the driving voltages output from the data driver 30 is corresponding to the first column. Striped portion of the graphic image 40, a nearly full black pattern 42 in the column 31, a striped portion of the graphic image 40 in the second column, a nearly black pattern 42 in the column 3 22 ... a graphic of the 321st column The driving voltages of the image 40 are in the horizontal and vertical directions, and the pattern 42 in the first column is almost completely black. In each vertical clock cycle, when OE 1 is active, the first column gate driving signal is input to the first column gate line so that the graphic image 40 of the first column is displayed on the LCD screen 3 4 and when OE 2 is in a movable state, the 3 21st column gate pushing signal is input to the 3 21st column gate line so that the 321st column displays a nearly black figure 42. Please refer to FIG. 6, which is a schematic diagram of a driving method of another driving circuit of the present invention. When the predetermined number of columns is two, the first column is the first column, and the predetermined pitch is 3 2 0, the scanning sequence in the driving method of the present invention is as shown in FIG. 6. Therefore, the first gate driver starts from the first column. The gate line sequentially displays the graphic image 40 of the two lines of the gate line 40 as shown in FIG. 6 on the first and second lines.

Page 13 1232427 V. Description of the Invention (ίο) Sections. Next, the second brake driver simultaneously displays a predetermined number of columns such as 2 from the 3rd and 2nd columns from the 3rd and 2nd columns from the first column and the 3rd and 2nd columns from the 3rd and 2nd column from the 2nd column. A graph represented by a driving voltage having a target value. Because the pattern represented by the driving voltage with the target value is a pattern close to completely black 4 2 and the predetermined number of columns is 2, the second gate driver simultaneously displays two columns close to completely black from the gate line of the 3 2 1st column. Figure 4 2. In other words, as shown in Fig. 6, the scanning order is to display the first column, the second to display the second column, and the third to display both the 3, 21, and 3 2 columns. Please refer to FIG. 7, which is another driving waveform diagram of the present invention. When the predetermined number of columns is 2 and the first column is the first column and the predetermined pitch is 3 2 0, the order of the driving voltages output from the data driver 30 is the line portion corresponding to the graphic image 40 of the first line , The column part of the graphic image 40 in the second column, the nearly black graphic 4 2 in the 3 2 1 column, and the nearly black graphic 42 in the 3 2 2 column ... the bar of the graphic image 40 in the 321 column The driving voltages of the column portion, the strip portion of the graphic image 40 of the 322th column, the nearly black pattern 42 in the first column, and the nearly black pattern 42 in the second column. As shown in Figure 7, in each vertical clock cycle, when OE 1 is active, the first row of gate push signals are input to the first row of gate lines to make the first row of graphic images 40 bars. The column part is displayed on the LCD screen 34, and the second column gate driving signal is input to the second column gate line so that the second column of the graphic image 40 is displayed on the LCD screen 34, and when OE 2 is available In the active state, the 321st gate and 3-22th gate push signals are simultaneously input to the 321st and 3222th gate lines to make the 321st and 3222th rows Simultaneously

Page 14 1232427 V. Description of the invention (11) The figure 4 which is almost completely black is displayed. Comparing Fig. 5 and Fig. 7, it can be found that, in Fig. 7 where the predetermined number of columns is more than 1, since the nearly black figure 4 2 such as 3 21 and 3 2 2 is displayed at the same time, it is only In 3 vertical clock signal periods, the display operations of the first column, the second 歹 ^, the 3 2 1 歹 J, and the 3 2 2 columns are completed. Compared with the four vertical clock signal periods shown in FIG. 5, One less vertical clock signal period. Based on the above description, theoretically, if the predetermined number of columns is increased, the required number of clock signal cycles can be reduced. It is specifically stated that the predetermined number of rows can be at most the same as the number of fixed gate lines, and when the predetermined number of rows is the same as the number of fixed gate lines, the required number of clock signal cycles will be very close to that required by the conventional LCD . Please refer to FIG. 8, which is a schematic diagram of resetting / presetting according to the present invention. The data driver 30 shown in FIG. 8 is connected to a reset line to receive a reset signal or connected to a preset line to receive a preset signal. When the driving voltage output by the data driver 30 through the digital / analog converter 80 is a driving voltage with a target value (that is, the gate driver 3 2 or 3 3 will be displayed as a nearly black figure 4 2) By resetting the signal, the data driver 30 causes all the pixel data temporarily stored in the data recorder 82 in the data driver 30 to be cleared, so that the driving voltage output by the data driver 30 has a target value. In addition, when the driving voltage output by the data driver 30 is a driving voltage having a target value, the data driver 30 enables the pixel data temporarily stored in all the data recorders 82 therein to be set by a preset signal at the same time. Into the default value, so that the output of the data drive 30

1232427 V. Description of the invention (12) The driving voltage has a target value. In this way, as long as the data driver 30 is additionally connected to the reset line to receive the reset signal or the preset line to receive the preset signal, there is no need to read the pixel data as shown in Figure 5 when the pixel data is read. The pixel data of the driving voltage of the value, and only need to read the pixel data of the image image sequentially as in the conventional technology. Therefore, such a method can drive the liquid crystal panel 3 4 with a fast gray-scale response time without increasing the horizontal clock signal of the data driver 30 when reading pixel data. However, the data driver 30 shown in FIG. 8 still needs to convert the pixel data temporarily stored in the data recorder 82 into a driving voltage by a digital / analog converter 80 and input it into the data line. Please refer to the data drive switch 90 shown in Figure 9. If the driving of the graphic image is converted by the driving voltage of the driving voltage line 90 of the driver, the driving value of the target value 80 can be set in the data. Figure 9 is a schematic diagram of the switch of the present invention. As shown in Figure 9, when the actuator 3 0 sets the driving voltage of the input data line to the corresponding partial voltage before the driving voltage is input to the data line, the driving voltage through the switch 90 is a digital / analog converter 8 0 conversion. If the input data is a driving voltage with a target value, the switching voltage is not a digital / analog conversion through the data driver 30, but the target voltage line is used to input the voltage without conversion. It is specifically stated that the digital / analog converter 8 0 drives 30 inside or outside.

Page 1232424 V. Description of the invention (13) In this way, the relationship between the data driver 30 and the digital / analog converter 80 as shown in FIG. 9 can not only increase the data driver 3 0 in the When reading the horizontal clock signal of the pixel data, the conversion of the digital / analog converter 80 can also be omitted, and the purpose of the present invention is also achieved, and the liquid crystal panel 34 is driven with fast grayscale response time. With the above detailed description of the preferred embodiments, it is hoped that the features and spirit of the present invention may be described more clearly, rather than limiting the scope of the present invention with the preferred specific embodiments disclosed above. On the contrary, the intention is to cover various changes and equitable arrangements within the scope of the patent to which the present invention is intended.

Page 17 1232427 Brief description of the diagrams Figures 1 A to 1 B are conventional driving waveforms. Figures 2A ~ 2C are schematic diagrams of the conventional analog pulse driving method. FIG. 3 is a schematic diagram of a driving circuit of the present invention. 4A to 4C are schematic diagrams of a driving method of a driving circuit according to the present invention. Fig. 5 is a driving waveform diagram of the present invention. FIG. 6 is a schematic diagram of a driving method of another driving circuit according to the present invention. FIG. 7 is another driving waveform diagram of the present invention. FIG. 8 is a schematic diagram of reset / preset of the present invention. FIG. 9 is a schematic diagram of a switch according to the present invention.

Schematic symbol description I, 2, 3, 4, 5, 6, 7 Frame II, 1 2, 1 3 Data frame 14, 15, 16, 16, 17, 18, 19, 20, 21, 22, 23, 24 , 25, 2 6, 2 7 Backlight 3 0 Data driver 3 2 Gate driver 3 4 LCD panel 4 0 Graphic image

4 2 Near black graphics 8 0 Digital / analog converter 8 2 Data logger 9 0 Switcher

Page 18

Claims (1)

1232427 6. Application patent scope 1. A driving method of a driving circuit, the driving method is to drive a liquid crystal panel by a plurality of data drivers and at least two gate drivers in the driving circuit, and one pixel of the liquid crystal panel The point is composed of a data line connected by the data driver and a gate line connected by the gate driver. When a driving voltage corresponding to at least one row of pixel points of a graphic image is input by the data line, the point The gate driver displays the graphic image on the liquid crystal panel in a row by a gate driving signal input by the gate line. The driving method includes: Based on a selection rule, a first gate driver is selected from at least two gate drivers, and the first gate driver sequentially displays a predetermined number of columns corresponding to the driving voltage from the gate lines in column A. Based on the selection rule, a second gate driver is selected from at least two gate drivers based on the selection rule, and the second gate driver is simultaneously from the gate line of the B column at a predetermined distance from the A column. The driving voltage with a target value of the predetermined number of columns is displayed on the ground, so that the pixel point from the predetermined number of columns of the B column is returned to the target value. 2. The driving method as described in item 1 of the scope of patent application, wherein the selection rule is based on, if the driving voltage output by the data driver is a part of the graphic image, the driving voltage is determined by the driving voltage. The gate driver whose representative figure is displayed on the liquid crystal panel is called the first gate driver. Page 19, 1232427 6. Application patent scope 4. The driving method as described in item 1 of the patent application scope, wherein the first gate driver and the second gate driver are allocated according to a resolution of the liquid crystal panel. The gate lines are connected such that the first gate driver and the second gate driver are connected to a fixed number of gate lines. 5. The driving method as described in item 4 of the scope of patent application, wherein the predetermined distance is greater than or equal to the number of fixed brake wires. 6. The driving method according to item 1 of the scope of patent application, wherein the data driver is connected to a reset line and receives a reset signal. When the driving voltage output by the data driver has the target, When the value of the driving voltage is reached, the data driver simultaneously clears all the pixel data temporarily stored in a data recorder by the reset signal, so that the driving voltage output by the data driver has The target value. 7. The driving method as described in item 1 of the scope of patent application, wherein the data driver is connected to another preset line to receive a preset signal. When the driving voltage output by the data driver has the target, Value of the driver Rules should be tangible. Selecting the dynamic medium-pressure meter with a chart drive should drive its electric brake. The second method to drive the third party to drive the electric drive is to drive out the drive. Then drive 1 drive, brake: ^ The pressure of the 'JI' moving plate of the surrounding I-power company, if the driving surface is-, the liquid-based value of the crystal green tt and the h are shown on the display. Page 20 1232427 6. When applying for a patent range voltage, the data driver simultaneously sets a pixel data temporarily stored by all the data recorders in it to a preset value by the preset signal, so that the The driving voltage output by the data driver has the target value. 8. The driving method according to item 1 of the scope of patent application, wherein a switch is provided before the driving voltage is input to the data line, and if the driving voltage input to the data line is a corresponding part of the graphic image When the driving voltage is used, the driving voltage passing through the switch is converted by a digital / analog converter of the data driver. 9. The driving method according to item 1 of the scope of patent application, wherein a switch is provided before the driving voltage is input to the data line, and if the driving voltage input to the data line is the driving voltage having the target value The driving voltage passing through the switch is not a conversion via a digital / analog converter of the data driver, but another target value line is used to input the driving voltage having the target value without conversion. Page 21