KR20080023451A - Plasma display device and driving method thereof - Google Patents

Abstract

A plasma display device and a driving method thereof are provided to perform a reliable address discharge by compensating for a variation in wall charges in discharge cells. In at least one sub-field, plural sustain electrodes are classified into plural groups having first and second groups. During a first reset period, discharge cells in the first group is initialized, and an address discharge is performed for the discharge cells in the first group during a first address period. During a second reset period, discharge cells in the second group is initialized, and a sustain discharge is performed on the discharge cells in the first and second groups during the sustain period. During the second address period, scan and address pulses longer than the pulsewidth in the first address period are applied. During the sustain period, sustain discharge pulses with different pulsewidths and voltage levels are applied to the discharge cells in the first and second groups.

Description

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

1 is a diagram illustrating a plasma display device according to an exemplary embodiment of the present invention.

2 illustrates a driving waveform of the plasma display device according to the first embodiment of the present invention.

3 illustrates a driving waveform of the plasma display device according to the second exemplary embodiment of the present invention.

4 illustrates a driving waveform of a plasma display device according to a third exemplary embodiment of the present invention.

5 is a view showing a driving waveform of the plasma display device according to the fourth embodiment of the present invention.

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

Plasma display devices are flat display devices that display characters or images using plasma generated by gas discharge, and dozens to millions or more of pixels are arranged in a matrix form according to their size.

The plasma display device is driven by dividing one frame into a plurality of subfields having respective weights. Each subfield consists of a reset period, an address period, and a sustain period. In this case, the reset period is a period for initializing the wall charge state in order to stably perform the address discharge, and the address period is a period for selecting (addressing) a cell to be turned on and a cell not to be turned on from the plurality of discharge cells. The sustain period is a period in which sustain discharge is performed for the cells to be turned on to actually display an image.

In general, in a method of driving a plasma display device, a scan pulse is sequentially applied to a scan electrode in an address period, and the address electrode forming a discharge cell to be selected from among the discharge cells formed by the scan electrode to which the scan pulse is applied. Apply an address pulse. Then, the address operation is sequentially performed from the first scan electrode to the last scan electrode.

As such, when the address operation is sequentially performed for all the discharge cells in the address period, in the discharge cells addressed later in time, the wall charges formed between the scan electrodes and the address electrodes may be lost or the priming particles inside the discharge cells may be insufficient. have. For this reason, there is a problem that an unstable address period is performed and low discharge may occur in the sustain period.

An object of the present invention is to provide a plasma display device and a driving method thereof capable of performing a stable address period and a sustain period.

According to an aspect of the present invention, a frame is included in a plasma display device including a plurality of first electrodes, a plurality of second electrodes, and a plurality of third electrodes formed in a direction crossing the first electrode and the second electrode. A method of driving by dividing into a plurality of subfields is provided. The driving method includes dividing the plurality of second electrodes into a plurality of groups including first and second groups, and a first group of discharge cells formed by the second electrodes of the first group in a first reset period. Initializing the step; selecting a discharge cell to be turned on among the discharge cells of the first group in a first address period; discharging cells of a second group formed by the second electrode of the second group in a second reset period; Initializing, selecting a discharge cell to be turned on among the discharge cells of the second group in a second address period, and sustaining and discharging the discharge cells of the selected first and second groups in a sustain period. Selectively applying a first scan pulse having a first pulse width to the plurality of first electrodes in one address period, and shorter than the first pulse width to the plurality of first electrodes in the second address period A second scan pulse having a second pulse width is selectively applied.

According to another aspect of the present invention, a method of dividing and driving one frame into a plurality of subfields in a plasma display device including a plurality of first electrodes and a plurality of second electrodes is provided. In this driving method, a first group of discharge cells are formed by dividing the plurality of second electrodes into a plurality of groups including first and second groups, and formed by second electrodes of the first group in a first reset period. Selecting a cell to be turned on from among the first group of discharge cells in a first address period after initializing the step; and forming a second electrode formed by the second electrode of the second group in a second reset period subsequent to the first address period. Initializing two groups of discharge cells, selecting a cell to be turned on from the discharge cells of the second group in a second address period, and sustaining discharge of the selected discharge cells of the discharge cells of the first and second groups in a sustain period; Steps. In this sustain period, a first voltage having a second voltage higher than the first voltage to the plurality of first electrodes while a first voltage is applied to the second electrodes of the first and second groups during the first period. Applying a sustain discharge pulse and applying a second sustain discharge pulse having the second voltage to a second electrode of the first group in a state where the first voltage is applied to the plurality of first electrodes for a second period; And applying a third sustain discharge pulse having the second voltage to the second electrode of the second group during the third period of the part of the second period, and then applying the first voltage for the remaining period of the second period. do.

According to still another feature of the present invention, a method of driving a plasma display device including a plurality of first electrodes and a plurality of second electrodes is provided. The driving method includes dividing the plurality of second electrodes into a plurality of groups including first and second groups, initializing discharge cells of the first group formed by the second electrodes of the first group, and then Selecting a cell to be turned on from among a first group of discharge cells, initializing a second group of discharge cells formed by the second electrode of the second group, and then selecting a cell to be turned on from the second group of discharge cells And sustaining and discharging a selected discharge cell among the discharge cells of the first and second groups in the sustain period, wherein during the first period in the sustain period, the plurality of first electrodes are formed in the discharge cells of the first group. And a first sustain discharge pulse that generates a first voltage difference between the first electrode and the second electrode of the first group, and between the plurality of first electrodes and the second electrode of the second group to discharge cells of the second group. A second electric charge smaller than the first voltage difference And it applies a second sustain discharge pulse that causes the difference.

According to another feature of the present invention, a plasma display panel including a plurality of first electrodes and a plurality of second electrodes, and the plurality of second electrodes into a plurality of groups including first and second groups. In the control unit and at least one subfield for controlling to divide and drive one frame into a plurality of subfields, initializing a discharge cell of a first group formed by the second electrode of the first group in a first reset period. Select a cell to be turned on from among the discharge cells of the first group in a first address period, initialize a discharge cell of a second group formed by the second electrode of the second group in a second reset period, and perform a second address Selecting a cell to be turned on from the discharge cells of the second group in a period, and applying a sustain discharge pulse having a first voltage to the plurality of first electrodes and the second electrodes of the first and second groups in a sustain period; It includes. The driving unit generates a first voltage difference between the plurality of first electrodes and the second electrodes of the first and second groups during the first period in the sustain period, and during the second period that is continuous with the first period. Generate the first voltage difference between the plurality of first electrodes and the second electrode of the first group, and generate the first plurality of electrodes and the second group of the second group during a third period of time of the second period; After generating the first voltage difference between the electrodes, a second voltage difference smaller than the first voltage difference is generated for the remaining period of the second period.

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.

And wall charges referred to throughout the specification refers to charges that are formed close to each electrode on the wall of the cell (eg, the dielectric layer). And the wall charge is not actually in contact with the electrode itself, but is described here as “formed”, “accumulated” or “stacked” on the electrode. In addition, a wall voltage refers to the potential difference formed in the wall of a cell by wall charge.

Throughout the specification, when a part is said to "include" a certain component, it means that it may further include other components, except to exclude other components unless otherwise stated.

Now, a plasma display device and a driving method thereof according to an exemplary embodiment of the present invention will be described in detail.

First, a schematic structure of a plasma display device according to an exemplary embodiment of the present invention will be described in detail with reference to FIG. 1.

1 is a diagram illustrating a plasma display device according to an exemplary embodiment of the present invention.

As shown in FIG. 1, a plasma display device according to an exemplary embodiment of the present invention includes a plasma display panel 100, a controller 200, an address electrode driver 300, a scan electrode driver 400, and a sustain electrode driver 500. It includes.

The plasma display panel 100 includes a plurality of address electrodes A1 to Am extending in the column direction, and a plurality of sustain electrodes X1 to Xn and scan electrodes Y1 to Yn extending in pairs in the row direction. Include. The sustain electrodes X1 to Xn are formed corresponding to the scan electrodes Y1 to Yn, and generally, one end thereof is commonly connected to each other. The plasma display panel 100 includes a substrate (not shown) on which the sustain and scan electrodes X1 to Xn and Y1 to Yn are arranged, and a substrate (not shown) on which the address electrodes A1 to Am are arranged. The two substrates are disposed to face each other so that the scan electrodes Y1 to Yn and the address electrodes A1 to Am and the sustain electrodes X1 to Xn and the address electrodes A1 to Am are orthogonal to each other. At this time, the discharge space at the intersection of the address electrodes A1 to Am and the sustain and scan electrodes X1 to Xn and Y1 to Yn forms a discharge cell. The structure of the plasma display panel 100 is an example, and a panel having another structure to which the driving waveform described below may be applied may also be applied to the present invention.

The controller 200 receives an image signal from the outside and outputs an address driving control signal, a sustain electrode X driving control signal, and a scan electrode Y driving control signal. The controller 200 divides and drives one frame into a plurality of subfields, and each subfield includes a reset period, an address period, and a sustain period when expressed as a change in time. According to the exemplary embodiment of the present invention, the control unit 200 may improve the low discharge problem that may be caused by the wall charges lost during the address period in the conventional method of driving the plasma display device. Control by dividing into a plurality of groups.

The address electrode driver 300 receives the address electrode A driving 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 scan electrode driver 400 receives the scan electrode Y driving control signal from the controller 200 and applies a driving voltage to the scan electrode Y.

The sustain electrode driver 500 receives the sustain electrode X driving control signal from the controller 200 and applies a driving voltage to the sustain electrode X.

Next, a driving waveform of the plasma display device according to the first embodiment of the present invention will be described in detail with reference to FIG. 2. Hereinafter, for convenience, a scan electrode (hereinafter referred to as a “Y electrode”), a sustain electrode (hereinafter referred to as an “X electrode”) and an address electrode (hereinafter referred to as an “A electrode”) forming one cell are applied. Only driving waveforms will be described.

2 illustrates a driving waveform of the plasma display device according to the first embodiment of the present invention.

The plasma display device according to the first embodiment of the present invention divides and drives a plurality of X electrodes into a plurality of groups. In FIG. 2, the plurality of X electrodes is divided into a first group X1 and a second group X2. For example, the first group X1 may represent an odd-numbered X electrode, the second group X2 may represent an even-numbered X electrode, and the plurality of X electrodes may be divided into a plurality of groups based on different criteria to be driven. . In the following, the discharge cells formed by the X and Y electrodes of the first group X1 and the A electrode crossing the same are referred to as the discharge cells of the first group X1, and the X and Y electrodes of the second group X2. The discharge cells formed by the electrodes and the A electrodes crossing them are called discharge cells of the second group X2.

According to the first embodiment of the present invention, in one subfield, the reset period is first performed on the discharge cells of the first group X1, and then the address period is performed, and then to the discharge cells of the second group X2. The address period is performed after performing the reset period. Then, the sustain period is performed in common for the discharge cells of the first and second groups X1 and X2.

Specifically, as shown in FIG. 2, the Y electrode of the Y electrode is applied to the X electrode of the first group X1 in the rising period of the first reset period R1 while the Vn voltage lower than the reference voltage (0 V in FIG. 2) is applied. The voltage is gradually raised from the reference voltage to the voltage Vs1. Then, in the falling period, the voltage of the Y electrode is gradually lowered from the reference voltage to the Vnf voltage while a Ve voltage higher than the reference voltage is applied to the X electrodes of the first group X1. In this case, the X electrode of the second group X2 is biased to a voltage Vs2 higher than the reference voltage during the rising period of the first reset period R1, and the reference voltage is applied during the falling period. In addition, the voltage of the A electrode is maintained at the reference voltage during the first reset period (R1). In this way, each electrode is formed by the voltage difference Vs1-Vn between the X electrode and the Y electrode of the first group X1 while the voltage of the Y electrode is gradually increased in the rising period of the first reset period R1. Discharge occurs between the wall charges in all the discharge cells of the first group X1. That is, (+) wall charges are formed at the X electrode of the first group (X1), and (-) wall charges are formed at the Y electrode. In the falling period of the first reset period R1, while the voltage of the Y electrode gradually decreases, a weak discharge occurs due to a voltage difference between the X electrode and the Y electrode of the first group X1, and thus, The wall charges that have been formed in the discharge cells are erased appropriately for the address operation. At this time, since the sum of the voltage difference between the X electrode and the Y electrode of the second group X2 and the formed wall voltage during the rising period of the first reset period R1 does not exceed the discharge start voltage, no discharge occurs.

As described above, the reason why the discharge does not occur between the X electrode and the Y electrode of the second group X2 in the first reset period R1 is as follows. In the sustain period (not shown) of the previous subfield, when the last sustain discharge pulse is applied, a voltage Vs is applied to the X electrodes of the first and second groups X1 and X2 and a reference voltage is applied to the Y electrode. Then, a sustain discharge occurs between the X and Y electrodes of the first and second groups X1 and X2 to form a negative wall charge on the X electrodes of the first and second groups X1 and X2, and to the Y electrode ( +) Wall charges are formed. Thereafter, in the rising period of the first reset period R1, the X electrode of the second group X2 rises to the voltage Vs1 while the voltage of the Y electrode rises to the voltage Vs1 while being biased with the voltage Vs2, so that the X electrode of the second group X2 The sum of the voltage difference (Vs1-Vs2) between the Y electrode and the Y electrode and the previously formed wall voltage does not exceed the discharge start voltage, so that no discharge occurs. Therefore, even after the rising period of the first reset period R1, the wall charge state between the X electrode and the Y electrode of the second group X2 maintains the wall charge state immediately after the sustain period of the previous subfield. In this state, if the voltage of the Y electrode is gradually decreased from the reference voltage to the Vnf voltage while the voltage of the X electrode of the second group X2 is maintained as the reference voltage in the falling period of the first reset period R1. The sum of the voltage difference Vnf between the X electrode and the Y electrode of the two groups X2 and the previously formed wall voltage does not exceed the discharge start voltage so that no discharge occurs. Therefore, the discharge cells of the second group X2 maintain the wall charge state immediately after the sustain period of the previous subfield during the first reset period R1.

Then, in the first address period A1, the voltage of the X electrode of the first group X1 is maintained at the Ve voltage, and the voltage of the X electrode of the second group X2 is maintained at the reference voltage. Apply a scan pulse to the. That is, in order to select a cell to emit light, the scan pulse Vscl is sequentially applied to the Y electrode, and the non-scan pulse Vsch is applied to the Y electrode to which the Vscl voltage is not applied. The address pulse Va is applied to the A electrode passing through the discharge cell to be selected from among the plurality of discharge cells formed by the Y electrode to which the Vscl voltage is applied, and the unselected A electrode is biased to the reference voltage. Then, an address discharge occurs in the discharge cells formed by the A electrode to which the Va voltage is applied and the Y electrode to which the Vscl voltage is applied, and then an address between the X electrode and the Y electrode of the first group X1 adjacent to the Y electrode where the discharge has occurred. Discharge occurs. Then, a positive wall charge is formed at the Y electrode, and a negative wall charge is formed at the A electrode and the X electrode of the first group X1, respectively. On the other hand, the sum of the voltage difference Vscl applied to the Y electrode and the X electrode of the second group X2 and the previously formed wall voltage does not exceed the discharge start voltage and thus is applied to the X electrode of the second group X2. No address discharge occurs.

Subsequently, in the rising period of the second reset period R2, the voltage of the Y electrode is gradually raised from the reference voltage to the voltage Vs1 while a voltage of Vn lower than the reference voltage is applied to the X electrodes of the second group X2. Then, in the falling period, the voltage of the Y electrode is gradually lowered from the reference voltage to the Vnf voltage while the Ve voltage higher than the reference voltage is applied to the X electrode of the second group X2. At this time, the X electrode of the first group X1 is biased to a voltage Vs2 higher than the reference voltage during the rising period of the second reset period R2, and the reference voltage is applied during the falling period. In addition, the voltage of the A electrode is maintained at the reference voltage during the second reset period (R2). In this case, while the voltage of the Y electrode gradually increases in the rising period of the second reset period R2, the voltage difference Vs1-Vn between the X electrode and the Y electrode of the second group X2 is increased between the respective electrodes. A discharge occurs to form wall charges in all the discharge cells of the second group X2. That is, (+) wall charges are formed at the X electrode of the second group (X2) and (-) wall charges are formed at the Y electrode. In the falling period of the second reset period R2, while the voltage of the Y electrode gradually decreases to the voltage Vnf, a weak discharge occurs due to the voltage difference between the X electrode and the Y electrode of the second group X2. The wall charges formed in the discharge cells of X2) are appropriately erased for the address operation. At this time, since the sum of the voltage difference between the X electrode and the Y electrode of the first group X1 and the wall voltage formed in the rising period of the second reset period R2 does not exceed the discharge start voltage, no discharge occurs.

Here, in the first and second reset periods R1 and R2, the states of all the cells of each group must be initialized, so the difference between the voltage Vs1 and the voltage Vn must be large enough to cause a discharge in the cells of all conditions. Further, the additional power can be reduced by setting the magnitudes of the voltages Vs1 and Vs2 to the same level as the high level voltage Vs of the sustain discharge pulses applied to the X and Y electrodes in the sustain period.

Then, in the second address period A2, the voltage of the X electrode of the second group X2 is maintained at the Ve voltage, and the voltage of the X electrode of the first group X1 is maintained at the reference voltage. Apply a scan pulse to the. That is, in order to select a cell to emit light, the scan pulse Vscl is sequentially applied to the Y electrode, and the non-scan pulse Vsch is applied to the Y electrode to which the Vscl voltage is not applied. The address pulse Va is applied to the A electrode passing through the discharge cell to be selected from among the plurality of discharge cells formed by the Y electrode to which the Vscl voltage is applied, and the unselected A electrode is biased to the reference voltage. Then, an address discharge occurs in the discharge cell formed by the A electrode to which the Va voltage is applied and the Y electrode to which the Vscl voltage is applied, and then an address between the X electrode and the Y electrode of the second group X2 adjacent to the Y electrode where the discharge has occurred. Discharge occurs. Then, positive wall charges are formed on the Y electrode, and negative wall charges are formed on the A electrode and the X electrode of the second group X2, respectively. On the other hand, the sum of the voltage difference Vscl applied to the Y electrode and the X electrode of the first group X1 and the wall voltage previously formed does not exceed the discharge start voltage, so that the X electrode of the first group X1 does not exceed the discharge start voltage. No address discharge occurs.

Next, in the sustain period S, the sustain discharge pulse having the high level voltage Vs and the low level voltage 0V at the Y electrode and the X electrodes of the first and second groups X1 and X2 is in the opposite phase. Is applied to cause sustain discharge in the selected discharge cells in the preceding first and second address periods. At this time, the widths of the sustain discharge pulses applied to the Y electrode and the X electrodes of the first and second groups X1 and X2 are the same in the T1 period. That is, as shown in FIG. 2, when the high level voltage Vs of the sustain discharge pulse is applied to one of the Y electrodes or the X electrodes of the first and second groups X1 and X2, the other electrode The low level voltage (0V) is applied. Then, in the first and second address periods A1 and A2, Y is caused by the voltage difference between the sustain discharge pulse and the wall voltage formed between the Y electrode and the X electrode of the first and second groups X1 and X2. A sustain discharge occurs between the electrode and the X electrodes of the first and second groups X1 and X2.

As described above, the reset operation is first performed on the discharge cells of the first group X1 and then the address operation is performed, and then the reset operation is performed on the discharge cells of the second group X2. By doing so, it is possible to reduce the time taken for the address operation to be performed on the last discharge cell after the reset period, thereby causing stable address discharge.

Meanwhile, a cell selected as a cell to be turned on among the discharge cells of the first group X1 in the first address period A1 may have a sustain period S after the second reset period R2 and the second address period A2 are performed. Will be performed. Therefore, below, the wall charges formed in the discharge cells of the first group X1 which may be lost in the discharge space during the second reset period R2 and the second address period A2 may be compensated. An embodiment of the present invention will be described in detail with reference to FIGS. 3 to 5.

3 illustrates a driving waveform of the plasma display device according to the second exemplary embodiment of the present invention. 3 is similar to the driving waveform and the operation described with reference to FIG. 2 except that scan pulses and address pulses applied in the first and second address periods A1 and A2 are different, and thus, detailed descriptions thereof will be omitted.

In FIG. 3, unlike in FIG. 2, the width of the scan pulse Vscl applied to the Y electrode in the first address period A1 is greater than the width of the scan pulse Vscl applied to the Y electrode in the second address period A2. Lengthen. In this case, although the width of each address pulse Va applied to the A electrode in the first and second address periods A1 and A2 is not shown in FIG. 3, the address applied to the A electrode in the first address period A1 is not shown. The width of the pulse Va is equal to the width of the scan pulse Vscl applied to the Y electrode, and the width of the address pulse Va applied to the A electrode in the second address period A2 is applied to the Y electrode. It can be set equal to the width of the scan pulse Vscl.

Specifically, when the scan pulse is sequentially applied to the Y electrode in the first address period A1, the Vscl voltage is applied during the T2 period. Thereafter, when the scan pulse is sequentially applied to the Y electrode in the second address period A2, the Vscl voltage is applied for a T3 period shorter than the T2 period. At this time, the period T3 is set to a width such that address discharge can occur between the Y electrode and the A electrode. As such, the widths of the scan pulses and the address pulses applied in the first address period A1 are longer than the widths of the scan pulses and the address pulses applied in the second address period A2, thereby turning on the first address period A1. The wall charges are further accumulated in the discharge cells of the first group X1 selected as the cells. Therefore, a stable sustain discharge is achieved by compensating wall charges of the discharge cells of the first group X1 which may be lost during the second reset period R2 and the second address period A2 after the first address period A1. Can be done.

Next, another embodiment for performing stable sustain discharge by compensating wall charges of the discharge cells of the first group X1 as in the second embodiment of the present invention will be described with reference to FIGS. 4 to 5.

4 illustrates a driving waveform of a plasma display device according to a third exemplary embodiment of the present invention.

In FIG. 4, the driving waveform and the similar operation to those described in FIG. 2 except for generating the sustain discharge by adjusting the widths of the first sustain discharge pulse and the second sustain discharge pulse applied in the sustain period S are described in detail. Description is omitted.

In FIG. 4, unlike in FIG. 2, the Y electrode and the X electrodes of the first and second groups X1 and X2 are extended by increasing the width of the first sustain discharge pulse Vs applied to the Y electrode in the sustain period S. To build up more wall charge. In addition, the walls of the X electrodes of the first group X1 that have previously performed the address operation by varying the widths of the second sustain discharge pulses Vs applied to the X electrodes of the first and second groups X1 and X2, respectively. Compensates for the charge and performs stable sustain discharge.

Specifically, when the first sustain discharge pulse Vs is applied to the Y electrode in the sustain period S, the reference voltage 0V is applied to the X electrodes of the first and second groups X1 and X2. At this time, in FIG. 2, the period T1 for applying the sustain discharge pulse Vs or the reference voltage 0V applied in the sustain period is the same, but in the third embodiment of the present invention, the Y electrode is applied to the Y electrode during the first sustain discharge pulse. The sustain discharge pulse Vs is applied during the T4 period longer than the T1 period. At this time, the reference voltage (0V) is applied to the X electrodes of the first and second groups (X1, X2) during the T4 period. By doing so, at the first sustain discharge, more wall charges are formed on the Y electrode and the X electrodes of the first and second groups X1 and X2 than in the first embodiment of the present invention.

However, in the case of the discharge cells of the first group X1 selected as the cells to be turned on in the first address period A1, the wall charges accumulated on the electrodes during the second reset period R2 and the second address period A2 are performed. It may be lost, and even if the width of the first sustain discharge pulse is increased in the sustain period S, an unstable sustain discharge may be caused. Therefore, in the third embodiment of the present invention, the width of the sustain discharge pulse Vs applied to the X electrodes of the first and second groups X1 and X2 is different when the first sustain discharge pulse is applied. That is, when the second sustain discharge pulse Vs is applied, the sustain discharge pulse Vs is applied to the X electrode of the first group X1 for a T5 period longer than the T1 period, and T5 is applied to the X electrode of the second group X2. The sustain discharge pulse Vs is applied for a period T6 shorter than the period. At this time, a reference voltage is applied to the Y electrode during the period of T5. The reference electrode (0 V) is applied to the X electrode of the second group X2 for the remaining period other than the T6 period in the T5 period. Here, the T5 period may be set to be the same as the T4 period, and the T6 period may be set to be the same as the T1 period. In this way, the wall charges are further accumulated in the discharge cells of the first group X1 in which the wall charges are lost during the second reset period R2 and the second address period A2, and then the first and second groups X1 are formed. , Sustain discharge of the same size occurs in the discharge cell of X2).

5 illustrates a driving waveform of the plasma display device according to the fourth embodiment of the present invention.

As shown in FIG. 5, in the fourth embodiment of the present invention, the width of the first sustain discharge pulse Vs applied to the Y electrode in the sustain period S is made longer than the T1 period, during which the first and second groups Different voltages are applied to the X electrodes of (X1, X2), respectively.

Specifically, when the first sustain discharge pulse Vs is applied to the Y electrode in the sustain period S, the sustain discharge pulse Vs is applied for a period T7 longer than the period T1 shown in FIG. 2. At this time, the voltage of the X electrode of the first group X1 is gradually reduced from the reference voltage (0 V in FIG. 5) to the Vn voltage, and a reference voltage (0 V) is applied to the X electrode of the second group X2. As such, when the first sustain discharge pulse is applied, when the voltage difference between the X electrode and the Y electrode of the first group X1 becomes larger, the discharge cells of the first group X1 are relatively larger than the discharge cells of the second group X2. Many wall charges build up. Therefore, the wall charges of the discharge cells of the first group X1 that have been lost during the previous second reset period R2 and the second address period A2 can be compensated to perform a stable sustain period.

In FIG. 5, the voltage of the X electrodes of the first group X1 decreases in a ramp form from the reference voltage to the Vn voltage during the T7 period, but in addition to the Vn voltage at the X electrodes of the first group X1 in addition to the reference voltage. Another voltage having a level lower than (0 V) may be applied to increase the difference between the voltage applied to the Y electrode and the voltage applied to the X electrode of the first group X1.

In addition, the voltage level of each electrode described in the first to fourth embodiments of the present invention may be changed to other voltage levels or other forms as long as the voltage difference between the A electrode, the X electrode, and the Y electrode is similar to the embodiment.

Although the 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 present invention defined in the following claims are also provided. It belongs to the scope of rights.

According to an embodiment of the present invention, by dividing a plurality of sustain electrodes into a plurality of groups and performing a reset period and an address period, respectively, the effect of performing a stable address period by compensating wall charges of a discharge cell performing an address operation in the second half is achieved. have.

Further, there is an effect that the intensity of the sustain discharge occurring in the discharge cells of the group performing the address operation in the first half and the discharge cells of the group performing the address operation in the second half can be equalized.

Claims (17)

In a plasma display device including a plurality of first electrodes, a plurality of second electrodes, and a plurality of third electrodes formed in a direction crossing the first electrode and the second electrode, a frame is driven by dividing a frame into a plurality of subfields. In the method, Dividing the plurality of second electrodes into a plurality of groups including first and second groups, Initializing a discharge cell of a first group formed by the second electrode of the first group in a first reset period; Selecting a discharge cell to be turned on among the discharge cells of the first group in a first address period; Initializing a second group of discharge cells formed by the second group of electrodes in a second reset period; Selecting a discharge cell to be turned on among the discharge cells of the second group in a second address period; and Sustaining and discharging the selected first and second groups of discharge cells in a sustaining period, Selectively applying a first scan pulse having a first pulse width to the plurality of first electrodes in the first address period, and shorter than the first pulse width to the plurality of first electrodes in the second address period. A method of driving a plasma display device for selectively applying a second scan pulse having two pulse widths. The method of claim 1, Selectively applying a first address pulse having a pulse width equal to the first pulse width to the plurality of third electrodes in the first address period, And selectively applying a second address pulse having a pulse width equal to the second pulse width to the plurality of third electrodes in the second address period. The method according to claim 1 or 2, In the first reset period, Gradually increasing the voltage of the plurality of first electrodes to a first voltage and then gradually decreasing to a second voltage, While the voltages of the plurality of first electrodes gradually rise, the second electrode of the first group is biased to a third voltage and the second electrode of the second group is biased to a fourth voltage higher than the third voltage, In the second reset period, Gradually increasing the voltages of the plurality of first electrodes to a fifth voltage, and then gradually decreasing the voltages to a sixth voltage, While the voltages of the plurality of first electrodes are gradually raised, the second electrode of the first group is biased to the seventh voltage and the second electrode of the second group is biased to the eighth voltage lower than the seventh voltage. Method of driving the display device. The method of claim 3, In the first reset period, While the voltages of the plurality of first electrodes are gradually falling, the second electrode of the first group is biased to the ninth voltage and the second electrode of the second group is biased to the tenth voltage lower than the ninth voltage. , In the second reset period, While the voltages of the plurality of first electrodes are gradually falling, the second electrode of the first group is biased to the eleventh voltage and the second electrode of the second group is biased to the twelfth voltage higher than the eleventh voltage. A method of driving a plasma display device. The method of claim 4, wherein The first and fifth voltages are the same as the voltages of the sustain discharge pulses applied to the plurality of first electrodes in the sustain period, And the fourth and seventh voltages are the same as the voltages of sustain discharge pulses applied to the second electrodes of the first and second groups in the sustain period. In the plasma display device including a plurality of first electrodes and a plurality of second electrodes to drive by dividing a frame into a plurality of subfields, Dividing the plurality of second electrodes into a plurality of groups including first and second groups, Selecting a cell to be turned on among the discharge cells of the first group in a first address period after initializing the discharge cells of the first group formed by the second electrode of the first group in a first reset period; Cells to be turned on among the discharge cells of the second group in the second address period after initializing the second group of discharge cells formed by the second electrodes of the second group in the second reset period subsequent to the first address period. Selecting a; And Sustaining and discharging a selected discharge cell among the discharge cells of the first and second groups in the sustain period, In the retention period, Applying a first sustain discharge pulse having a second voltage higher than the first voltage to the plurality of first electrodes while a first voltage is applied to the second electrodes of the first and second groups during a first period; , Applying a second sustain discharge pulse having the second voltage to a second electrode of the first group in a state in which the first voltage is applied to the plurality of first electrodes during a second period, Applying a third sustain discharge pulse having the second voltage to a second electrode of the second group during a third period of a portion of the second period, and then applying the first voltage for the remaining period of the second period A method of driving a plasma display device. The method of claim 6, In the retention period, And a width of the first and second sustain discharge pulses is wider than a width of the sustain discharge pulse applied after the second period. The method according to claim 6 or 7, And the width of the third sustain discharge pulse is equal to the width of the sustain discharge pulse applied after the second period. The method of claim 6, And the first period is a period continuous to the second address period. In the method of driving a plasma display device comprising a plurality of first electrodes and a plurality of second electrodes, Dividing the plurality of second electrodes into a plurality of groups including first and second groups, Initializing a discharge cell of the first group formed by the second electrode of the first group and selecting a cell to be turned on among the discharge cells of the first group; Initializing a discharge cell of the second group formed by the second electrode of the second group and selecting a cell to be turned on among the discharge cells of the second group; And Sustaining and discharging a selected discharge cell among the discharge cells of the first and second groups in the sustain period, During the first period of time in the holding period, Applying a first sustain discharge pulse to generate a first voltage difference between the plurality of first electrodes and the second electrode of the first group to the discharge cells of the first group, And applying a second sustain discharge pulse to the discharge cells of the second group to generate a second voltage difference smaller than the first voltage difference between the plurality of first electrodes and the second electrodes of the second group. Driving method. The method of claim 10, For the remaining period except the first period in the maintenance period, Applying a third sustain discharge pulse to generate the second voltage difference to the discharge cells of the first and second groups, And the third sustain discharge pulse width is smaller than the first and second sustain discharge pulse widths. The method according to claim 10 or 11, wherein And wherein the second voltage difference is a voltage difference causing a sustain discharge to a cell selected as a cell to be turned on among discharge cells of the first and second groups. A plasma display panel including a plurality of first electrodes and a plurality of second electrodes; A control unit for dividing the plurality of second electrodes into a plurality of groups including first and second groups and controlling one frame to be divided into a plurality of subfields; And In at least one subfield, Initialize a discharge cell of the first group formed by the second electrode of the first group in a first reset period, Selecting a cell to be turned on from among the discharge cells of the first group in a first address period, Initialize a second group of discharge cells formed by the second electrode of the second group in a second reset period, Selecting a cell to be turned on from among the discharge cells of the second group in a second address period, A driving unit configured to apply a sustain discharge pulse having a first voltage to the plurality of first electrodes and the second electrodes of the first and second groups in a sustain period, The driving unit, Generating a first voltage difference between the plurality of first electrodes and the second electrodes of the first and second groups during the first period in the sustain period, Generating the first voltage difference between the plurality of first electrodes and the second electrode of the first group during a second period subsequent to the first period, Generating the first voltage difference between the plurality of first electrodes and the second electrode of the second group during a third period of a portion of the second period, and then than the first voltage difference for the remaining period of the second period. A plasma display device for generating a small second voltage difference. The method of claim 13, The driving unit, After the second period, the first voltage difference is generated by applying a sustain discharge pulse having a first pulse width between the plurality of first electrodes and the second electrodes of the first and second groups, And the first and second periods are longer than the first pulse width. The method according to claim 13 or 14, The driving unit, In the rising period of the first and second reset period, the voltage of the plurality of first electrodes is gradually increased to the first voltage, and then the voltages of the plurality of first electrodes are lower than the first voltage in the falling period. Gradually drop to voltage, Generating a first voltage difference and a second voltage difference smaller than the first voltage difference between the plurality of first electrodes and the second electrodes of the first and second groups, respectively, in the rising period of the first reset period, Generating a third voltage difference and a fourth voltage difference smaller than the third voltage difference between the plurality of first electrodes and the second electrodes of the first and second groups, respectively, in the falling period of the first reset period, Generating a fifth voltage difference and a sixth voltage difference greater than the fifth voltage difference between the plurality of first electrodes and the second electrodes of the first and second groups, respectively, in the rising period of the second reset period, A plasma display for generating a seventh voltage difference and an eighth voltage difference greater than the seventh voltage difference between the plurality of first electrodes and the second electrodes of the first and second groups, respectively, in the falling period of the second reset period. Device. The method of claim 13, And the first period is a period continuous to the second address period. The method of claim 13, And the first voltage difference is a voltage difference causing a sustain discharge to a cell selected as a cell to emit light in the first and second address periods.

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