KR100738818B1 - Plasma Display Apparatus and Driving Method thereof - Google Patents

Abstract

The present invention relates to a plasma display device and a driving method thereof.

In the plasma display apparatus and its driving method according to the present invention, a plurality of subfields are divided into a reset period, an address period, and a sustain period, and the plurality of sustain electrodes are divided into a plurality of sustain electrode groups in the address period, and the set-down period of the reset period is performed. And a voltage lower than the bias voltage is applied to at least one sustain electrode group of the plurality of sustain electrode groups to which a bias voltage is applied during a predetermined period, and a predetermined period of time to which a voltage lower than the bias voltage is applied is the plurality of sustain electrode groups. And the first half of the set-down period and the address period in the latter half sustain group corresponding to the scan electrode which is scanned later among the three sustain electrode groups.

Description

Plasma display device and driving method thereof {Plasma Display Apparatus and Driving Method}

1 is a perspective view showing the structure of a three-electrode AC surface discharge type PDP having a discharge cell structure arranged in a matrix form according to the related art.

2 is a waveform diagram according to a driving method of a conventional plasma display panel.

3 is a view showing a state of wall charges according to a driving waveform of a conventional plasma display panel.

4 schematically illustrates a plasma display device according to the present invention;

5 is a view showing a waveform diagram and a wall charge state for explaining a first driving method of the plasma display device according to the present invention;

6 is a waveform diagram illustrating a second driving method of the plasma display device according to the present invention;

7 is a waveform diagram illustrating a third driving method of the plasma display device according to the present invention;

<Explanation of symbols for the main parts of the drawings>

100: plasma display panel 121: timing control unit

122: data driver 123: scan driver

124: sustain driver 125: drive voltage generator

The present invention relates to a plasma display device and a driving method thereof.

In general, a plasma display panel (hereinafter referred to as "PDP") displays an image including a character or a graphic by emitting phosphors by 147 nm ultraviolet rays generated when a He + Xe or Ne + Xe inert mixed gas is discharged. Done.

1 is a perspective view showing the structure of a three-electrode AC surface discharge type PDP having a discharge cell structure arranged in a matrix form. Referring to FIG. 1, the three-electrode AC surface discharge type PDP 100 includes a scan electrode 11a and a sustain electrode 12a formed on the upper substrate 10, and an address electrode formed on the lower substrate 20. 22). Each of the scan electrode 11a and the sustain electrode 12a is formed of a transparent electrode, for example, indium tin oxide (ITO). Metal bus electrodes 11b and 12b for reducing resistance are formed on each of the scan electrode 11a and the sustain electrode 12a. An upper dielectric layer 13a and a passivation layer 14 are stacked on the upper substrate 10 on which the scan electrode 11a and the sustain electrode 12a are formed. Wall charges generated during plasma discharge are accumulated in the upper dielectric layer 13a. The protective layer 14 prevents damage to the upper dielectric layer 13a due to sputtering generated during plasma discharge, and increases emission efficiency of secondary electrons. As the protective film 14, magnesium oxide (MgO) is usually used.

Meanwhile, the lower dielectric layer 13b and the partition wall 21 are formed on the lower substrate 20 on which the address electrode 22 is formed, and the phosphor layer 23 is formed on the surfaces of the lower dielectric layer 13b and the partition wall 21. Is applied. The address electrode 22 is formed in the direction crossing the scan electrode 11a and the sustain electrode 12a. The partition wall 21 is formed in parallel with the address electrode 22 to prevent ultraviolet rays and visible light generated by the discharge from leaking to the adjacent discharge cells. The phosphor layer 23 is excited by ultraviolet rays generated during plasma discharge to generate visible light of any one of red (R), green (G), and blue (B). An inert mixed gas such as He + Xe or Ne + Xe for discharging is injected into the discharge space of the discharge cell partitioned by the partition wall 21 between the upper substrate 10 and the lower substrate 20. Looking at the driving method of the conventional PDP having such a structure as shown in FIG.

2 is a waveform diagram according to a driving method of a conventional plasma display panel. As shown in FIG. 2, the waveform diagram of the conventional plasma display panel driving method includes a reset section, an addressing section, and a sustain section, and the reset section is a set-up section. And set-down intervals.

In the setup section, a high-voltage rmap up pulse is applied to the scan (Y) electrode so that positive wall charges are accumulated on the sustain (Z) electrode and the address (X) electrode, and negative wall charges are applied to the scan (Y) electrode. Piles up.

In the set down period, the wall charges accumulated excessively by the high-pressure ramp up pulses are uniformly reduced to a certain level due to the application of a ramp down pulse.

In the addressing period, addressing discharge is generated by the scan pulse of the scan (Y) electrode and the data pulse of the address (X) electrode, and the sustain voltage (Vs) is maintained at the sustain (Z) electrode. At this time, the bias voltage Vs applied to the sustain (Z) electrode is maintained such that the scan pulse applied to the scan (Y) electrode and a voltage not causing discharge are maintained.

In the sustain period, sustain discharge is performed by applying a sustain pulse to the scan (Y) electrode and the sustain (Z) electrode alternately.

3 illustrates a state of wall charges according to a driving waveform of a conventional plasma display panel. Figure 3 (a) shows the state of the wall charge formed by the setup discharge generated by the high-pressure ramp up pulse in the setup period. It can be seen that a large number of wall charges are formed on the scan (Y) electrode, the sustain (Z) electrode, and the address (X) electrode by the ramp-up pulse of the high voltage.

Figure 3 (b) shows the state of the wall charge formed by the discharge process by the lamp down pulse in the set down period. Excessive accumulated wall charges are removed to a certain level by the ramp down pulses, thereby making the wall charges of each cell uniform.

(C) of FIG. 3 shows the state of the wall charge immediately after the scan pulse and the data pulse are applied to the scan (Y) electrode and the address (X) electrode in the addressing period, respectively. It can be seen that when compared to the reversed.

3 (d) shows the wall charge state in the second half of the addressing section in the cell in which the addressing discharge has already occurred in the first half of the addressing section, and it can be seen that much of the wall charge is lost as compared with FIG. . As such, the wall charge state of the cell formed by the addressing discharge in the first half of the addressing period should be maintained until the second half of the addressing period. However, if much wall charge is lost as shown in FIG. A problem occurs.

In particular, as shown in (d) of FIG. 3, the wall charge state of the cell in which the address discharge has already occurred cannot be maintained until the second half of the addressing period, and the wall charge is lost as follows.

That is, the higher the resolution of the plasma display panel, the longer the addressing period becomes. Thus, wall charges formed by the addressing discharge of the initial scan line as shown in FIG. 3C continue until the addressing period ends as shown in FIG. Since the same scan (Y) electrode and the sustain (Z) electrode are in the voltage state, wall charges are lost due to natural coupling of charges after a long time.

The present invention for solving the above problems is to provide a plasma display device and a driving method thereof that can generate a stable discharge without erroneous discharge during high resolution or high temperature driving.

In order to achieve the above object, a plasma display device and a method of driving the same according to the present invention divide a plurality of sustain electrodes into a plurality of sustain electrode groups in the address period because a plurality of subfields are divided into a reset period, an address period, and a sustain period. And applying a voltage lower than the bias voltage to at least one sustain electrode group of the plurality of sustain electrode groups to which a bias voltage is applied during the setdown period and the address period of the reset period, for a predetermined period. The predetermined period during which the low voltage is applied is characterized in that the set-down period and the first half of the address period in the latter half sustain group corresponding to the scan electrode which is scanned later among the plurality of sustain electrode groups.

The voltage lower than the bias voltage is characterized in that the positive voltage.

A voltage lower than the bias voltage is smaller than the bias voltage and is above ground level.

The number of the plurality of sustain electrode groups may be two or more.

When the number of the sustain electrode groups is two, the sustain electrodes may be divided into odd and even numbers.

The number of sustain electrodes belonging to the plurality of sustain electrode groups may be the same.

The number of sustain electrodes belonging to the plurality of sustain electrode groups is different.

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

4 is a schematic view showing a plasma display device according to the present invention. As shown in FIG. 4, the plasma display apparatus according to the present invention supplies data to the plasma display panel 100 and the address electrodes X1 to Xm formed on the lower substrate (not shown) of the plasma display panel 100. A data driver 122 for driving, a scan driver 123 for driving the scan electrodes Y1 to Yn, a sustain driver 124 for driving the sustain electrodes Z which are common electrodes, and a plasma display For driving the panel, the timing controller 121 for controlling the data driver 122, the scan driver 123, and the sustain driver 124, and for supplying driving voltages to the respective driving units 122, 123, and 124. The driving voltage generator 125 is included.

The plasma display panel 100 is bonded to an upper substrate (not shown) and a lower substrate (not shown) at regular intervals, and a plurality of electrodes, for example, scan electrodes Y1 to Yn and a sustain electrode, are attached to the upper substrate. Za and Zb are formed in pairs, and address electrodes X1 to Xm are formed on the lower substrate to intersect the scan electrodes Y1 to Yn and the sustain electrodes Za and Zb. As shown in the drawing, the sustain electrode formed on the upper substrate is grouped with odd-numbered Za and even-numbered Zb in the electrode arrangement order to form a sustain electrode group. Here, the sustain electrode group is divided into two sustain groups of the first sustain electrode group and the second sustain electrode group by grouping odd and even numbers, but the number of groups of the sustain electrodes may be divided into two or more.

In addition, the number of each of the sustain electrodes belonging to the plurality of sustain electrode groups may be the same, and at least one of the number of the sustain electrodes belonging to the plurality of sustain electrode groups may be different.

The data driver 122 is subjected to inverse gamma correction and error diffusion by an inverse gamma correction circuit, an error diffusion circuit, and the like, and then data mapped to each subfield is supplied by the subfield mapping circuit. The data driver 122 samples and latches data in response to the timing control signal CTRX from the timing controller 121, and then supplies the data to the address electrodes X1 to Xm.

The scan driver 123 supplies the rising ramp waveform Ramp-up and the falling ramp waveform Ramp-down to the scan electrodes Y1 to Yn during the reset period under the control of the timing controller 121. In addition, the scan driver 123 maintains the scan bias voltage Vsc during the address period under the control of the timing controller 121 while maintaining the scan pulse Sp of the scan voltage -Vy to the scan electrodes Y1 to Yn. Supply sequentially.

In this case, the scan driver 123 first scans the odd-numbered scan electrodes Y1, Y3, Y5,... Among the plurality of scan electrodes Y1 to Yn formed in the plasma display panel, and then even-numbered scans. The electrodes Y2, Y4, Y6, ... are scanned. That is, the scan driver 123 sequentially scans the scan electrodes corresponding to the sustain electrode group grouped into odd-numbered and even-numbered groups. Of course, when the number of sustain electrode groups is three or more, the scan driver 123 sequentially scans corresponding scan electrodes such as the sustain electrode group divided into two groups. Although not shown, the scan driver includes a first scan driver and a second scan driver to independently drive the odd-numbered scan electrode lines and the even-numbered scan electrode lines, respectively, according to the number of sustain electrode groups. Can be.

The sustain driver 124 supplies the bias voltage of the positive voltage to the sustain electrodes Za and Zb during the set down period and the address period during which the ramp ramp is generated under the control of the timing controller 121. do. At this time, the sustain driver 124 applies a voltage lower than the positive bias voltage to the sustain electrode group of the plurality of sustain electrode groups for a predetermined period during the set down period and the address period. A detailed driving method thereof will be described in detail in the driving method of the plasma display apparatus according to the present invention. In addition, the sustain driver 124 causes the sustain driving circuit provided therein to alternately operate with the sustain driving circuit provided in the scan driver 123 to supply the sustain pulse su to the sustain electrodes Z during the sustain period. do.

The timing controller 121 receives the vertical / horizontal synchronization signal and the clock signal and receives timing control signals for controlling operation timing and synchronization of the driving units 122, 123, and 124 in the reset period, the address period, and the sustain period. Each of the driving units 122, 123, and 124 is controlled by generating (CTRX, CTRY, CTRZ) and supplying the timing control signals CTRX, CTRY, and CTRZ to the corresponding driving units 122, 123, and 124.

The data control signal CTRX includes a sampling clock for sampling data, a latch control signal, a switch control signal for controlling on / off time of the sustain driving circuit and the driving switch element. The scan control signal CTRY includes a switch control signal for controlling on / off time of the sustain driving circuit in the scan driver 123 and the driving switch element, and the sustain control signal CTRZ includes the sustain in the sustain driver 124. A switch control signal for controlling the on / off time of the driving circuit and the driving switch element is included.

The driving voltage generator 125 generates a setup voltage Vsetup, a scan common voltage Vscan-com, a scan voltage -Vy, a sustain voltage Vs, a data voltage Vd, and the like. These driving voltages may vary depending on the composition of the discharge gas or the structure of the discharge cell.

Looking at the driving method according to the plasma display device of the present invention having such a structure as shown in FIG.

5 is a view illustrating a waveform diagram and a wall charge state for explaining a first driving method of the plasma display apparatus according to the present invention. As shown, the first driving method of the plasma display apparatus according to the present invention is the top and bottom of the scan electrode (Y1, Y2, Y3, ...) formed on the plasma display panel with respect to the center line of the plasma display panel Although driving may be performed by dividing into, the odd-numbered scan electrodes Y1, Y3, ... corresponding to the first sustain electrode group Za and the even-numbered scan electrodes Y2, corresponding to the second sustain electrode group Zb Drive by dividing by Y4, ...).

For convenience of description, the odd-numbered scan electrode is referred to as the front half scan electrode, and the first sustain electrode group Za corresponding thereto is also referred to as the front half sustain electrode group, and the even-numbered scan electrode is referred to as the second half scan electrode and corresponds to the first scan electrode. The 2 sustain electrode group (Zb) is also referred to as the latter half sustain electrode group. Here, the first half scan electrode refers to a scan electrode that scans first based on the scan order among the scan electrodes formed on the plasma display panel in the address period, and the second half scan electrode later scans based on the scan order in the address period. Means.

The first half scan electrodes Y1, Y3, ... corresponding to the first sustain electrode group Za divided into two groups and the second half scan electrodes Y2, Y4 corresponding to the second sustain electrode group Zb In the reset period, the rising ramp pulse Ramp-up is applied in the setup period a, and the falling ramp pulse Ramp-down is supplied in the set-down period b. At this time, a positive bias voltage Vz is applied to the first sustain electrode group Za and the second sustain electrode group Zb. The positive bias voltage Vz may be equal to the magnitude of the voltage Vs of the sustain pulse applied in the sustain period.

Thereafter, during the address period, the scan pulse Sp is sequentially applied to the first half scan electrodes Y1, Y3, ... and the second half scan electrodes Y2, Y4, .... In this case, the first half sustain electrode group Za and the second half sustain electrode group Zb are driven differently.

That is, in the first half sustain electrode group Za, the positive bias voltage Vz is maintained from the first half c to the second half c 'of the addressing period. In the second half sustain electrode group Zb, a voltage Vz 'lower than the positive bias voltage is maintained in the first half c of the address period, and the positive bias voltage Vz is held in the second half c' of the address period. ) Is maintained. In this manner, when the voltage Vz 'lower than the positive bias voltage is maintained in the first half c of the address period with respect to the second half sustain electrode group Zb, the positive charge can be maintained at the sustain electrode, resulting in an error in the addressing period. Discharge can be prevented. At this time, the voltage Vz 'lower than the positive bias voltage is preferably the ground level GND as shown by the dotted line. In addition, the first sustain electrode group Za maintains the positive bias voltage, which holds the negative charge accumulated in the first sustain electrode group Za after the addressing discharge, so that the second sustain electrode group Zb stably addresses the addressing discharge. To do that.

6 is a waveform diagram illustrating a second driving method of the plasma display device according to the present invention.

Referring to FIG. 6, the second driving method of the plasma display device according to the present invention is the same as the first driving method. However, in the latter half sustain electrode group Zb, the voltage Vz 'lower than the positive bias voltage is maintained not only in the first half c of the address period but also in the setdown period b of the reset period. At this time, the voltage Vz 'which is lower than the positive bias voltage in the set-down period b of the reset period as well as the first half c of the address period may be the ground level GND.

7 is a waveform diagram illustrating a third driving method of the plasma display device according to the present invention.

Referring to FIG. 7, in the third driving method of the plasma display apparatus according to the present invention, the sustain electrode group is divided into three groups (Za, Zb, and Zc), and a scan in which the scan is performed late in an address period among the three sustain electrode groups is performed in time. The sustain electrode group Zc corresponding to the electrode is driven longer than the other sustain electrode group Zb in which the voltage Vz 'lower than the positive bias voltage Vz is maintained.

That is, the first sustain electrode group Za is applied during the address period in which the scan pulse Sp is applied to the scan electrodes Y1, Y4, Y7, ... corresponding to the set-down period b of the reset period (c, d, e) the positive bias voltage Vz is maintained,

The second sustain electrode group Zb maintains the positive bias voltage Vz during the set-down period b of the reset period, and the voltage Vz lower than the positive bias voltage Vz in the initial period c of the address period. ') Is maintained When the scan pulse Sp is applied to the corresponding scan electrodes Y2, Y5, Y8, ..., the positive bias voltage Vz is maintained.

Lastly, like the second sustain electrode group, the third sustain electrode group Zc maintains the positive bias voltage Vz during the set-down period b of the reset period, and the initial period c and the middle period d of the address period. Is maintained at a lower voltage (Vz ') than the positive bias voltage (Vz). When a scan pulse (Sp) is applied to the corresponding scan electrodes (Y3, Y6, Y9, ...) (e) (Vz) is maintained.

As described above, the driving method of the plasma display apparatus according to the present invention divides the sustain electrodes into a plurality of groups when the positive bias voltage is applied to the sustain electrodes in the set-down period and the address period of the reset period, and biases each sustain electrode group. By controlling the voltage application time, it is possible to prevent the loss of wall charges and to achieve stable discharge. In addition, it is possible to suppress the discharge delay phenomenon caused by the instability of the driving conditions in the addressing section.

In particular, this driving method is more effective in the stable discharge characteristics in a high temperature environment or a plasma display device having a high resolution.

As such, the technical configuration of the present invention described above can be understood by those skilled in the art that the present invention can be implemented in other specific forms without changing the technical spirit or essential features of the present invention.

Therefore, the exemplary embodiments described above are to be understood as illustrative and not restrictive in all respects, and the scope of the present invention is indicated by the appended claims rather than the foregoing detailed description, and the meaning and scope of the claims are as follows. And all changes or modifications derived from the equivalent concept should be interpreted as being included in the scope of the present invention.

As described above, the present invention has the effect of preventing erroneous discharge due to wall charge loss in a high temperature environment or high resolution.

In addition, the present invention can stabilize the addressing driving conditions, thereby reducing the discharge delay phenomenon in the address period.

Claims (18)

A plasma display panel having a plurality of sustain electrodes formed thereon; A sustain electrode driver for driving the sustain electrode; And A voltage lower than the bias voltage is applied to at least one sustain electrode group of the plurality of sustain electrode groups to which the plurality of sustain electrodes are divided into a plurality of sustain electrode groups, and the sustain electrode driver is applied with a bias voltage during a set down period and an address period. And a timing controller for controlling the sustain electrode driver to apply the voltage for a predetermined period of time. The predetermined period during which a voltage lower than the bias voltage is applied And a set-down period and a first half address period in a second half sustain group corresponding to a scan electrode to be scanned later among the plurality of sustain electrode groups. delete delete The method of claim 1, And a voltage lower than the bias voltage is a positive voltage. The method of claim 4, wherein And a voltage lower than the bias voltage is smaller than the bias voltage and above a ground level. The method of claim 1, And the number of the plurality of sustain electrode groups is two or more. The method of claim 6, And when the number of the sustain electrode groups is two, the sustain electrodes are divided into odd-numbered and even-numbered groups. The method of claim 1, And the number of sustain electrodes belonging to the plurality of sustain electrode groups is the same. The method of claim 1, And at least one of the number of sustain electrodes belonging to the plurality of sustain electrode groups is different. A driving method of a plasma display apparatus in which a plurality of subfields are driven by being divided into a reset period, an address period, and a sustain period. The plurality of sustain electrodes are divided into a plurality of sustain electrode groups in the address period, and at least one of the plurality of sustain electrode groups to which a bias voltage is applied during the set down period and the address period of the reset period is less than the bias voltage. Applying a low voltage for a period of time, The predetermined period during which the voltage different from the bias voltage is applied And a set-down period and an address period of the first half in the latter half sustain group corresponding to the scan electrodes which are scanned later among the plurality of sustain electrode groups. delete delete The method of claim 10, And a voltage lower than the bias voltage is a positive voltage. The method of claim 13, And a voltage lower than the bias voltage is smaller than the bias voltage and above a ground level. The method of claim 10, And the number of the plurality of sustain electrode groups is two or more. The method of claim 15, And when the number of the sustain electrode groups is two, the sustain electrodes are divided into odd-numbered and even-numbered groups. The method of claim 10, And the number of sustain electrodes belonging to the plurality of sustain electrode groups is the same. The method of claim 10, And at least one of the number of sustain electrodes belonging to the plurality of sustain electrode groups is different.

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