KR100749484B1 - Plasma display device and driving method thereof - Google Patents

Abstract

According to the present invention, after the address operation is performed on one of the scan electrode lines, the sustain discharge operation on the scan electrode line is performed only after the address operation of the last scan electrode line is completed. In order to solve the problem that a considerable time gap occurs until the occurrence of the sustain discharge operation becomes unstable, the cells of the plasma display panel including the plurality of scan electrodes and the plurality of sustain electrodes are divided into a plurality of groups, and the frame In expressing gradation in the subfield method, it is possible to minimize the temporal gap between the address period and the sustain period, so that smooth sustain discharge can occur in the sustain period. In this case, in at least one sustain period of the plurality of sustain periods, at least one sustain discharge pulse of the sustain discharge pulses applied to the scan electrodes of at least one group of the plurality of groups is the remaining scan electrode except the scan electrode. And an intermediate level of the sustain discharge pulse applied to the corresponding sustain electrode.

PDP, address / hold mix period, sustain discharge, minimum unit light

Description

Plasma display device and driving method thereof {PLASMA DISPLAY DEVICE AND DRIVING METHOD THEREOF}

1 is a diagram illustrating a gray scale display method of a conventional plasma display panel.

2 is a schematic conceptual diagram of a plasma display device according to an exemplary embodiment of the present invention.

FIG. 3 is a diagram for describing a driving method of a plasma display device in which a scan electrode line is divided into a plurality of (n) groups, and one frame is divided into a plurality of subfields for each group.

FIG. 4 is a diagram illustrating an example in which scan electrodes of a plasma display panel according to a first exemplary embodiment are divided into odd and even electrode lines.

FIG. 5 is a driving waveform diagram of a plasma display device according to a first exemplary embodiment of the present invention in which the driving method described with reference to FIG. 4 is applied to an odd line group Yodd, an even line group Yeven, and a sustain electrode X of the scan electrode. to be.

The present invention relates to a plasma display device including a plasma display panel (PDP) and a driving method thereof.

A plasma display device is a flat display device that displays characters or images by using plasma generated by gas discharge. In the display panel, tens to millions or more of pixels are arranged in a matrix form according to their size.

In general, a plasma display device divides one frame into a plurality of subfields SF1-SF8 having respective weights (1T, 2T, 4T, 8T, 16T, 31T, 64T, and 128T) and time-divisionally controls them to implement gradation. Each subfield SF1-SF8 has a reset period (not shown), an address period Ad1-Ad8, and a sustain period S1-S8. The reset period is a period of initializing the state of each cell in order to perform an address operation smoothly on the cell. The address period is a wall charge on a cell (addressed cell) that is turned on to distinguish a cell that is turned on and a cell that is not turned on. This is the period during which the stacking operation is performed. The sustain period is a period in which a discharge for actually displaying an image on an addressed cell is applied by applying a sustain discharge voltage pulse.

1 is a diagram illustrating a gray scale expression method of a conventional plasma display panel.

As shown in FIG. 1, the conventional method of driving a plasma display device sequentially completes an address operation from the first scan electrode line Y1 to the last scan electrode line Yn, and then simultaneously holds all the cells in the sustain period. It is to perform the discharge operation. According to such a driving method, after an address operation is performed on one scan electrode line, the sustain discharge operation in the scan electrode line is performed only after the address operation of the last scan electrode line is completed. Therefore, there is a problem that a significant time gap occurs until the sustain discharge operation occurs in the cell in which the address operation has occurred, and thus the sustain discharge operation may become unstable.

Accordingly, an object of the present invention is to provide a plasma display device and a driving method thereof capable of reducing a time gap between an address operation and a sustain discharge operation.

In addition, it is to ensure the gradation linearity due to the mismatch in the number of sustain discharges between the gradations.

In the plasma display panel including a plurality of scan electrodes and a plurality of sustain electrodes forming a plurality of cells according to an aspect of the present invention for solving this problem, the plurality of scans and electrodes are divided into a plurality of groups, A driving method of a plasma display device in which one frame is divided into a plurality of subfields for each group, wherein the subfields have a plurality of address periods corresponding to the plurality of groups and the plurality of groups in common. A common sustain period for performing sustain discharge, and in the first subfield,

Selecting cells to be displayed from among the cells of the group in the address period of each group, and performing sustain discharge of the first number of cells to be displayed among the cells of the plurality of groups in the common sustain period. Characterized in that.

According to another aspect of the present invention, a plasma display device includes a plasma display panel including a plurality of scan electrodes and a plurality of sustain electrodes, a driver for applying a driving signal to the scan electrodes, and the plurality of scan electrodes into a plurality of groups. And a control unit for controlling the driving unit by dividing each subfield into a plurality of address periods corresponding to the plurality of groups, and a common sustain period for performing sustain discharge in common with the plurality of groups.

The driving unit sequentially performs an address discharge for selecting a cell to be displayed among the cells of the group in the address period of each group in the first subfield, and in the common sustain period, Characterized in that the number of times of sustain discharge.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention. Like parts are designated by like reference numerals throughout the specification.

A plasma display device and a driving method thereof according to an exemplary embodiment of the present invention will now be described in detail with reference to the accompanying drawings.

First, a plasma display device according to an exemplary embodiment of the present invention will be described with reference to FIG. 2. 2 is a schematic conceptual diagram of a plasma display device according to an exemplary embodiment of the present invention.

As shown in FIG. 2, a plasma display device according to an exemplary embodiment of the present invention includes a plasma display panel 100, a controller 200, an address driver 300, a sustain electrode driver 400, and a scan electrode driver 500. Include. The plasma display panel 100 includes a plurality of address electrodes A1-Am arranged in the column direction, a plurality of sustain electrodes X1-Xn arranged in the row direction, and a plurality of scan electrodes Y1-Yn. do. The plurality of scan electrodes Y1-Yn and the sustain electrodes X1-Xn are arranged in pairs with each other. The discharge cells are formed by the adjacent scan electrodes, the sustain electrodes, and the address electrodes crossing them.

The controller 200 receives an image signal from the outside and outputs an address driving control signal, a sustain electrode driving control signal, and a scan electrode driving control signal. The controller 200 divides and drives one frame into a plurality of subfields, and each subfield is represented by a reset period, an address period, and a sustain period. The address driver 300 receives an address drive control signal from the controller 200 and applies a display data signal for selecting a discharge cell to be displayed to each address electrode. The sustain electrode driver 400 receives the sustain electrode driving control signal from the controller 200 and applies a driving voltage to the sustain electrode X. The scan electrode driver 500 receives a scan electrode driving control signal from the controller 200 and applies a driving voltage to the scan electrode Y.

Next, a driving method of the plasma display device according to the first embodiment of the present invention will be described with reference to FIGS. 3 to 5.

FIG. 3 is a diagram for describing a driving method of a plasma display device in which a scan electrode line is divided into a plurality of (n) groups, and one frame is divided into a plurality of subfields for each group. In FIG. 3, each group is represented by a combination of eight subfields.

Meanwhile, in the method of dividing the scan electrode lines into a plurality of groups, groups may be formed by grouping a predetermined number of scan electrode lines in a physical arrangement order. For example, when the panel is formed of 800 scan electrode lines, the first to 100th scan electrode lines may be set as the first group and the 101st to 200th scan electrode lines may be set as the second group while being divided into eight groups. However, in grouping the scan electrode lines, adjacent neighboring lines may not be collected, but scan electrode lines spaced apart from each other may be collected in the same group. That is, the first, 9, 17, ... (8k + 1) th scan electrode lines are allocated to the first group, and the second, 10, 18, ... (8k + 2) th scan electrodes are allocated to the second group. Allocating lines. On the other hand, if necessary, it is possible to group the scan electrode lines even in an irregular manner.

FIG. 4 is a diagram illustrating an example in which scan electrodes of a plasma display panel according to a first exemplary embodiment are divided into odd and even electrode lines. One subfield consists of a reset period R, an address / sustain mixing period T1, and a common sustain period T2.

The reset period R initializes the wall charge state of the cell by applying reset pulses to the scan electrode lines of all groups.

The address / sustain mixing period T1 sequentially performs an address operation from the first scan electrode line of the odd line Yodd to the last scan electrode line (Aodd). When all the address operations are completed for the cells of the odd line Yodd, at least one sustain pulse is applied to the scan electrode Yodd of the odd line to perform the sustain discharge operation (Sodd).

When the sustain period (Sodd) of the odd line (Yodd) is finished, the address operation for the cells of the even line (Yeven) is performed (Aeven).

When the address period Aeven of the even line Yeven ends, that is, when all address operations for the scan electrode lines belonging to the even line Yeven are completed, the sustain period Seven for the even line Yeven is performed. do. When the sustain period Seven for the even line Yeven ends, a common sustain period T2 is performed in which sustain discharge is performed in common for the odd line Yod and the even line Yeven.

At this time, the first sustain discharge occurs once in each of the odd and even lines in the address / sustain mixing period T1, and then the sustain discharge occurs in common in the common sustain period T2 to satisfy the gray level between the odd and even lines. As described above, at least two sustain discharge pulses may be generated so that the sustain discharge is also performed on the odd line Yodd which has already been addressed in the sustain period Seven after the end of the even period Yeven. Can be authorized. In this case, a luminance difference equal to the number of sustain discharges generated during the sustain period Seven in the odd line Yod occurs, and a predetermined additional sustain period is required to equally correct the luminance difference between the lines. For this purpose, it may further include a luminance correction period (not shown) which is a sustain discharge period selectively performed for each line so that the gray levels of the cells of each line are equally corrected with each other.

On the other hand, the common sustain period T2 is selectively used when the gradation degree specification assigned to each subfield is not satisfied by the address / sustain mixing period T1 or the address / sustain mixing period T1 and the luminance correction period. Can be performed. The common holding period T2 may be performed after the address / hold mixing period T1 or may be performed after the luminance correction period.

In addition, the size of the common sustain period T2 may be appropriately changed according to the weight of the subfield.

In addition, one subfield may be implemented only in the address / sustain mixing period T1. Specifically, after the address operation and the sustain discharge operation on the odd line Yod are completed, the address operation and the sustain discharge operation of the even line Yeven are sequentially performed.

FIG. 5 is a driving waveform diagram of a plasma display device according to a first exemplary embodiment of the present invention in which the driving method described with reference to FIG. 4 is applied to an odd line group Yodd, an even line group Yeven, and a sustain electrode X of the scan electrode. to be.

In the reset period R, a reset waveform is applied to the odd and even scan electrode groups Yodd and Yeven to initialize the wall charge state of the cell. Since the reset waveform of FIG. 5 is a general waveform, detailed description thereof will be omitted.

In the address / sustain mixing period T1, first, an address period Aodd and a sustain period Sodd for the odd line group Yodd of the scan electrode are performed. Next, the address period Aeven and the sustain period Seven of the even line group Yeven are performed.

In the address period Aodd, the scan pulses having the VscL voltage are sequentially applied to the scan electrodes of the odd line group Yodd while the scan electrodes Yeven of the even line group are maintained at the VscH voltage. At this time, the VscH voltage is also applied to the scan electrodes of the odd line group Yodd without the scan pulse. Although not shown, an address voltage is applied to an address electrode forming a cell to be displayed among cells formed by a scan electrode to which a scan pulse is applied. Then, an address discharge occurs due to a difference between the address voltage applied to the address electrode and the voltage VscL applied to the scan electrode and the wall voltage caused by the wall charges formed on the address electrode and the scan electrode, thereby forming a wall voltage on the scan electrode and the sustain electrode. do.

In the sustain period Sodd of the address / sustain mixing period T1, a sustain discharge pulse is applied to the scan electrodes Yodd and Yeven and the sustain electrode X alternately. In FIG. 5, one sustain discharge pulse is applied to the scan electrodes Yodd and Yeven and the sustain electrode X, respectively. In addition, the sustain discharge pulse has a high level voltage (Vs voltage in FIG. 5) and a low level voltage (0V or VscH voltage in FIG. 5), and the voltage Vs or (Vs-VscH) may cause sustain discharge along with the wall voltage. That is the voltage. First, a Vs voltage is applied to the scan electrodes Yod and Yeven and 0 V is applied to the sustain electrode X, and a wall is formed between the scan electrode Yodd and the sustain electrode X by the address discharge in the address period Aodd. In the cell in which the voltage is formed, sustain discharge occurs due to the wall voltage and the voltage difference Vs between the scan electrode Yodd and the sustain electrode X, so that the wall voltages having opposite polarities are applied to the scan electrode Yodd and the sustain electrode X. Is formed. On the other hand, the sustain discharge pulse is also applied to the even-numbered scan electrodes Yeven during the sustain period Sodd of the address / sustain mixing period T1, but a wall voltage is formed between the scan electrodes Yeven and the sustain electrodes X. There is no maintenance discharge.

As such, when the address period Aodd and the sustain period Sod of the address / sustain mixing period T1 are completed for the scan electrodes Yod of odd lines, the address / sustain mixing period for the even electrodes of even lines The address period Aeven of (T1) is performed.

With respect to the even-numbered scan electrodes Yeven, in the address period Aeven of the address / sustain mixing period T1, the scan electrodes Yod of the odd-numbered lines are kept in sequence with the scan electrodes Yeven while maintaining the VscH voltage. A scan pulse with a VscL voltage is applied. At this time, the VscH voltage is also applied to the scan electrodes of the even line group Yeven to which the scan pulse is not applied. As described above, the wall voltage is formed by applying the address voltage to the address electrode A forming the cell to be displayed among the cells formed by the scan electrode Yeven to which the VscL voltage is applied. In FIG. 5, although a part of the sustain period Sodd and a part of the address period Aeven overlap, the two periods Sodd and Aeven may be separated.

In the sustain period Seven of the address / sustain mixing period T1, a sustain discharge pulse having an alternating Vs voltage and a 0V voltage is applied to the even-numbered scan electrode Yeven and the sustain electrode X. Then, sustain discharge occurs in a cell in which the wall voltage is formed in the address period Aeven among the cells of the even line Yeven. On the other hand, in the sustain period Seven, the discharge is not generated in the cells of the odd line Yodd, and the discharge is generated only in the cells of the even line Yeven. To this end, when the sustain discharge pulse of the Vs voltage is applied to the sustain electrode X, a Vs / 2 voltage between the Vs voltage and the 0V voltage is applied to the scan electrode Yodd of the odd line. Then, the voltage difference Vs-Vs / 2 between the scan electrode Yodd and the sustain electrode X of the odd line does not reach the discharge start voltage Vf, so that no discharge occurs and only the even line scan electrode group Yeven is maintained. Discharge occurs.

At this time, in order to cause the discharge to occur only in the even-numbered scan electrodes Yeven in the sustain period Seven, the voltage applied to the odd-numbered scan electrodes Yodd is equal to the discharge start voltage (S). If the voltage does not reach Vf), other voltages having a magnitude between Vs and 0V may be used in addition to the above-mentioned Vs / 2 voltage. Alternatively, a voltage equal to the sustain discharge pulse voltage (Vs voltage in FIG. 5) applied to the sustain electrode X may be applied. Then, a voltage Vs is applied to the sustain electrode X, and a voltage of 0 V is applied to the scan electrodes Yodd and Yeven of odd and even lines. Then, since there is no previous sustain discharge in the cells of the odd line scan electrode Yodd, the wall voltage is formed to be reverse polarity, so that sustain discharge does not occur, and sustain discharge occurs in the cells of the even line scan electrode Yeven.

Then, in the common sustain period T2, sustain discharge pulses are applied to the scan electrodes Yodd and Yeven and the sustain electrode X to perform sustain discharge in common with all the scan electrodes Yodd and Yeven.

In FIG. 5, five sustain discharges occur each of the scan electrode groups Yodd and Yeven.

In this way, sustain discharges in the sustain periods (Sodd, Seven) and the common sustain period (T2) of each of the scan electrode groups (Yodd and Yeven) of odd and even lines are applied to each of the scan electrode groups (Yodd and Yeven). The total number of sustain discharges generated is equally seven times.

Meanwhile, the number of sustain discharges according to the number of sustain discharge pulses applied to the corresponding subfield to explain a method of implementing sustain discharge for gray scale expression in the method of driving the plasma display device according to the first embodiment of the present invention as described above. The information is shown in Table 1 below.

 Subfield Sodd Seven T2 Number of maintenance discharges Y, X Y, X Y, X Y SF1 SKIP SKIP SKIP 0.5 1 time SF2 One One One 0.5 5 times SF3 One One 2 0.5 7th SF4 One One 3 0.5 9th

Referring to Table 1, in order to implement a discharge discharge, an independent maintenance period, that is, a maintenance period (Sodd or Seven) performed for each group (Yodd and Yeven) in a corresponding subfield, is performed for a predetermined period in all groups. The common sustain period T2 is performed to express the gray level in the corresponding subfield as the sum of light.

In this case, the number of sustain discharge pulses 1 in Table 1 means when a pulse having a Vs voltage is applied to the scan electrode Y and the sustain electrode X once. That is, one sustain discharge pulse represents the case where the pulse of the Vs voltage is applied to the sustain electrode X after the pulse of the Vs voltage is applied to the scan electrode Y. In Table 1, 0.5 sustain discharge pulses represent a case where a pulse of Vs voltage is applied only to the scan electrode (Y).

On the other hand, in the plasma display device according to the first embodiment of the present invention, the number of sustain discharge pulses allocated to the minimum weight subfield is 0 to less than 1. That is, in order to realize the minimum unit light, the sustain periods Sodd and Seven and the common sustain period T2 of each group are not performed, and 0.5 sustain discharge pulses are applied to the scan electrode Y. As a result, the smallest unit light in the minimum weight subfield (subfield 1) may be realized by one sustain discharge by the sustain discharge pulse applied to the scan electrode (Y).

In this way, the light intensity of the minimum weight subfield can be reduced. However, as shown in Table 1, if the number of sustain discharges (5 times in Table 1) of the subfield having the weight after the minimum weight subfield is more than one time, the luminance difference may increase between one gray level and two gray levels. That is, gray scale linearity may not be guaranteed. Hereinafter, an example in which gray scale linearity may be maintained will be described with reference to Table 2.

The sustain discharge implementation method according to the second embodiment of the present invention is common to each scan electrode group (Yodd, Yeven) when the number of sustain discharges in the corresponding subfield is one or more times in the sustain discharge implementation method according to the first embodiment of the present invention. Since the implementation methods are the same except that the number of sustain discharges in the sustain period T2 is the same, redundant descriptions are omitted.

Therefore, in the second embodiment of the present invention, the number of sustain discharge pulses applied to the common sustain period of the subfield in which the total number of sustain discharges is two or more times in Table 1 is subtracted to adjust the total number of sustain discharges in the corresponding subfield. do. That is, when the number of sustain discharge pulses 1 is subtracted, as described above, application of a pulse having a Vs voltage to the scan electrode Y and the sustain electrode X once is omitted, thereby reducing the total number of sustain discharges twice.

In this way, if the number of pulses applied in the common holding period is adjusted in a subfield in which the total number of sustain discharges in the corresponding subfield is two or more times, as shown in Table 2, the number of sustain discharges between the minimum weighted subfield and the next subfield is determined. The gray level linearity can be maintained by reducing a large difference.

That is, in Table 2, the total number of sustain discharge pulses in subfield 2 having a larger weight than subfield 1, which is the minimum weight subfield, is 1.5. The total number of sustain discharges is three times. Next, the total number of sustain discharge pulses in subfield 3, which is a subfield having a larger weight than that of subfield 2, is 2.5. The total number of sustain discharges is five times. Next, the total number of sustain discharge pulses in subfield 4, which is a subfield having a greater weight than that of subfield 3, is 3.5. The total number of sustain discharges is seven times.

That is, the gray scale linearity can be maintained because the number of sustain discharges in the minimum weight subfield and the next subfield increases once and three times, and then increases constantly, such as five times and seven times.

 Number of sustain discharge pulses Sodd Seven T2 Number of maintenance discharges Y, X Y, X Y, X Y SF1 SKIP SKIP SKIP 0.5 1 time SF2 One One SKIP 0.5 3rd time SF3 One One One 0.5 5 times SF4 One One 2 0.5 7th

On the other hand, unlike the second embodiment of the present invention, the number of sustain discharge pulses in each sustain period (Sodd, Seven) in the address / sustain mixing period (T1) for each scan electrode group (Yodd, Yeven) is adjusted in each group Even if the total number of sustain discharges is equal to that of the second embodiment, the same effects as in the second embodiment of the present invention can be obtained.

All frames may not be formed as frames having subfields described in the first and second embodiments. In general, a plasma display device uses a method of limiting the total number of sustain discharge pulses allocated to one frame according to the screen load ratio in order to reduce power consumption. This method is called automatic power control. When the total number of sustain discharge pulses is determined, the number of sustain discharge pulses allocated to each subfield is determined according to the weight of the subfields.

For automatic power control, the control unit 500 of FIG. 2 measures the screen load ratio for each frame and limits the power consumption by reducing the total number of sustain discharge pulses when the screen load ratio is high. That is, the controller 500 consumes more discharge cells that are turned on when the screen load rate is high, so that the power consumption increases. Since the power is low, the luminance is increased by reducing the number of sustain discharge pulses (the number of fat-dielectric discharges).

Therefore, the controller 500 may apply the method described in the first and second embodiments of the present invention when the screen load ratio is higher than the threshold and the number of sustain discharge pulses allocated to the minimum weight subfield is 1 or less.

 Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the invention defined in the following claims are also provided. It belongs to the scope of rights.

As described above, according to the present invention, the cells constituting the display panel can be driven in a plurality of groups without the addition of a driving circuit. In addition, when the cells constituting the display panel are divided into a plurality of groups without the addition of a driving circuit, and the gray level is expressed in a frame-subfield method, the temporal gap between the address period and the sustain period is minimized to facilitate the maintenance period. Maintenance discharge can occur.

In addition, it is possible to solve the problem of weakness in gray scale linearity and color band phenomenon due to the difference in the number of times of discharge discharge between gray scales.

Claims (20)

delete In a plasma display panel including a plurality of scan electrodes and a plurality of sustain electrodes forming a plurality of cells, the plurality of scan electrodes are divided into a plurality of groups, and one frame is divided into a plurality of subfields for each group. In the driving method of the plasma display device, The subfield includes a plurality of address periods corresponding to each of the plurality of groups and a common sustaining period for performing sustain discharge in common with the plurality of groups. In the first subfield, Selecting cells to be displayed from cells of the corresponding group in the address period of each group; And Performing sustain discharge a first number of times for cells to be displayed among the cells of the plurality of groups in the common sustain period; And the first number of times is one time. In a plasma display panel including a plurality of scan electrodes and a plurality of sustain electrodes forming a plurality of cells, the plurality of scan electrodes are divided into a plurality of groups, and one frame is divided into a plurality of subfields for each group. In the driving method of the plasma display device, The subfield includes a plurality of address periods corresponding to each of the plurality of groups and a common sustaining period for performing sustain discharge in common with the plurality of groups. Selecting cells to be displayed from cells of the group in an address period of each group in a first subfield; Performing sustain discharge of the first number of times for cells to be displayed among the cells of the plurality of groups in the common sustain period in the first subfield; Selecting cells to be displayed from cells of each group in an address period of each group in a second subfield having a greater weight than the first subfield; Performing sustain discharge of the second number of times for cells to be displayed in the group immediately after the address period of each group in the second subfield; And And performing sustain discharge of the first number of times of cells to be displayed among the cells of the plurality of groups in the common sustain period of the second subfield. The method of claim 3, The second number of times is two, and the first number of times is one time. The method of claim 3, In a third subfield having a greater weight than the second subfield, Selecting cells to be displayed from cells of each group in the address period of each group; Performing sustain discharge three times on cells to be displayed in the group immediately after the address period of each group; And Performing sustain discharge four times for the cells to be displayed among the cells of the plurality of groups in the common sustain period; And the sum of the third number and the fourth number is greater than the sum of the first number and the second number. The method of claim 5, And wherein the third number of times is equal to the second number of times. The method of claim 6, The fourth number is two times greater than the first number, Wherein the first number of times is one time and the second number of times is two times. The method according to any one of claims 2 to 7, And the first subfield is a minimum weight subfield of one frame. The method according to any one of claims 2 to 7, And when the number of sustain discharges is one, sustain discharge pulses are applied to the scan electrodes and low sustain discharge pulses are applied to the sustain electrodes. The method according to any one of claims 2 to 7, And when the number of sustain discharges is two or more times, sustain discharge is performed by alternately applying a high level sustain discharge pulse and a low level sustain discharge pulse to the scan electrode and the sustain electrode. The method according to claim 2 or 3, The frame including the first subfield is a frame when the screen load ratio is greater than or equal to a threshold. The method according to claim 2 or 3, At least one of sustain discharge pulses applied to the scan electrode or the sustain electrode in at least one group of the plurality of groups in at least one sustain period performed for each group after an address period corresponding to the plurality of groups, respectively. And a level at which the sustain discharge pulse prevents sustain discharge from occurring between the scan electrode and the sustain electrode. The method of claim 12, And the at least one sustain discharge pulse is an intermediate level between a high level and a low level of the sustain discharge pulse. A plasma display panel including a plurality of scan electrodes and a plurality of sustain electrodes; A driving unit applying a driving signal to the scan electrode; And The driving unit divides the plurality of scan electrodes into a plurality of groups, and divides each subfield into a plurality of address periods corresponding to the plurality of groups and a common sustain period for performing sustain discharge in common to the plurality of groups. It includes a control unit for controlling, The driving unit, In the first subfield, In the address period of each group, an address discharge for selecting a cell to be displayed among cells of the group is sequentially performed, In the common sustain period, a plasma discharge device performing a first number of sustain discharges in common for all groups. The method of claim 14, And said first number of times is one time. The method of claim 14, In a second subfield having a greater weight than the first subfield, Selecting cells to be displayed from the cells of each group in the address period of each group, and performing sustain discharge of the second number of cells to be displayed in the group immediately after the address period of each group; And sustain discharge of the first number of times of cells to be displayed among the cells of the plurality of groups in the common sustain period. The method of claim 16, In a third subfield having a greater weight than the second subfield, Selecting cells to be displayed from among the cells of each group in the address period of each group, and performing sustain discharge three times for the cells to be displayed in the group immediately after the address period of each group; And a fourth time of sustain discharge for the cells to be displayed among the cells of the plurality of groups in the common sustain period. The method of claim 17, The sum of the third number of times and the fourth number of times is greater than the sum of the first number of times and the second number of times. The method of claim 14, And the first subfield is a minimum weight subfield of one frame. The method of claim 14, The frame including the first subfield is a frame when the screen load ratio is greater than or equal to a threshold.

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