KR100533724B1 - Driving method and apparatus of plasma display panel - Google Patents

Abstract

The present invention relates to a method and apparatus for driving a plasma display panel that can improve display quality and reliability.

In the plasma display panel driving method, a subframe period is divided into a plurality of subfields, and each subfield is time-divided into a reset period, an address period, and a sustain period to display an image. Varying the duty value of the sustain pulse applied in the sustain period according to the weight of the field; The duty value is reduced as the subfield expressing the high luminance weight among the subfields.

Description

Method and apparatus for driving plasma display panel {DRIVING METHOD AND APPARATUS OF PLASMA DISPLAY PANEL}

The present invention relates to a plasma display panel, and more particularly, to a method and apparatus for driving a plasma display panel capable of improving display quality and reliability.

Recently, there is a growing interest in flat panel displays that can reduce the weight and volume of cathode ray tubes. Such flat panel displays include Liquid Crystal Display (LCD), Plasma Display Panel (PDP), Field Emission Display (FED), Electro-Luminescence (EL) And digital signals or analog data to the display panel.

The plasma display panel emits phosphors by 147 nm ultraviolet rays generated when the inert mixed gases such as He + Xe, Ne + Xe, and He + Ne + Xe gases are discharged to display images and video including characters or graphics. The plasma display panel is not only thin and large in size, but also greatly improved in image quality due to recent technology development.

In particular, the three-electrode AC surface discharge type plasma display panel accumulates wall charges using a dielectric layer during discharging, thereby lowering the voltage required for discharging, and has advantages of low voltage driving and long life because it protects the electrodes from sputtering of plasma.

1 is a perspective view showing a discharge cell structure of a three-electrode AC surface discharge type plasma display panel.

Referring to FIG. 1, a discharge cell of a three-pole current alternating surface discharge plasma display panel is formed on a scan electrode Y and a sustain electrode Z formed on an upper substrate 10, and a lower substrate 18. The address electrode X is provided.

Each of the scan electrode Y and the sustain electrode Z has a line width smaller than that of the transparent electrodes 12Y and 12Z and the transparent electrodes 12Y and 12Z, and is formed on the metal bus electrode 13Y, which is formed at one edge of the transparent electrode. 13Z).

Indium tin oxide (ITO) is generally used as a material of the transparent electrodes 12Y and 12Z. As the material of the metal bus electrodes 13Y and 13Z, a metal such as chromium (Cr) is usually used. The metal bus electrodes 13Y and 13Z are formed on the transparent electrodes 12Y and 12Z to reduce the voltage drop caused by the transparent electrodes 12Y and 12Z having high resistance. The upper dielectric layer 14 and the passivation layer 16 are stacked on the upper substrate 10 having the scan electrode Y and the sustain electrode Z side by side. In the upper dielectric layer 14, charged particles generated by gas discharge ionization gas (plasma) are accumulated. The protective layer 16 protects the upper dielectric layer 14 from sputtering of charged particles generated during gas discharge and increases the emission efficiency of secondary electrons. As the bottom film 16, magnesium oxide (MgO) is usually used. The address electrode X is formed in a direction crossing the scan electrode Y and the sustain electrode Z. The lower dielectric layer 22 and the partition wall 24 are formed on the lower substrate 18 on which the address electrode X is formed.

The phosphor layer 26 is formed on the surfaces of the lower dielectric layer 22 and the partition wall 24. The partition wall 24 is formed to be parallel to the address electrode X to physically distinguish the discharge cells, and prevent ultraviolet rays and visible light generated by the discharge from leaking to the adjacent discharge cells. The phosphor layer 26 is emitted by ultraviolet rays generated during gas discharge to generate visible light of any one of red (R), green (G), and blue (B). Inert mixed gases such as He + Xe, Ne + Xe, and He + Ne + Xe for discharging are injected into the discharge space provided between the upper and lower substrates 10 and 18 and the partition wall 24.

The three-electrode AC surface discharge type plasma display panel is driven by dividing one frame into several subfields having different emission counts in order to realize gray levels of an image. Such a driving method of the plasma display panel is roughly classified into a selective writing (SW) method and a selective erasing (SE) method according to whether the discharge cells selected by the address discharge are emitted.

2 is a frame configuration diagram of a plasma display panel using a selective writing method.

Referring to FIG. 2, each subfield of the selective write method SW has a reset period for generating discharge uniformly, an address period for selecting a Banggen cell, a sustain period for implementing gray scale according to the number of discharges, and a sustain period. It is divided into an erasing period for erasing wall charges formed in all the discharge cells. For example, in the case where an image is to be displayed with 265 gray levels, one frame period (16.67 ms) corresponding to 1/60 second is divided into eight subfields SF1 to SF8. Each of the eight subfields is divided into a reset period, an address period, a sustain period, and an erase period. The reset period and the address period of each subfield are the same for each subfield, while the sustain period and the number of discharges thereof are 2 ⁿ in each subfield (where n = 0, 1, 2, 3, 4, 5, 6, 7) is increased in proportion. The erase period is arranged in the last subfield of the eight subfields. As such, gray scales can be implemented by combining subfields having different sustain periods.

The selective write (SW) driving method selects the discharge cells by turning off the full screen in the reset period and turning on the discharge cells with the write discharge in the address period. In the sustain period, images are displayed by causing the discharge cells selected in the address period to maintain discharge. In the reset period, the electric charges formed by the sustain discharge in the sustain period are erased.

3 is a waveform diagram illustrating a driving waveform of the plasma display panel according to the selective writing method.

In FIG. 3, X represents a data electrode, Y represents a scan electrode, and Z represents a signal waveform supplied to the sustain electrode. The selective write (SW) driving method of the plasma display panel includes a reset period for initializing the full screen, an address period for selecting a cell, a sustain period for maintaining the discharge of the selected cell, and an erase period for erasing charges formed by the sustain discharge. It is driven by dividing by.

The reset period is divided into a setup period and a setdown period by the waveform applied to the scan electrode (Y).

In the setup period, a ramp-up waveform, in which the voltage value rises to the sustain voltage Vs value and then the voltage value rises over time, is simultaneously applied to all the scan electrodes Y. At the same time, the ground voltage GND is applied to the sustain electrode Z and the address electrode X.

The scan electrode (Y) and the sustain electrode (Z) between the scan electrode (Y) and the address electrode (X) in the cells of the full screen by a ramp-up waveform applied to the scan electrodes (Y). Priming discharge occurs between. Due to the priming discharge, positive wall charges are accumulated on the address electrode X and the sustain electrode Z, and negative wall charges are accumulated on the scan electrode Y.

During the set-down period, after the ramp-up waveform is supplied, it starts to fall over time at the sustain voltage (Vs) lower than the peak voltage of the ramp-up waveform, and then the base voltage (GND). Alternatively, a ramp-down waveform that drops to a specific voltage of negative polarity is simultaneously applied to the scan electrodes Y. At the same time, a positive sustain voltage Vs is applied to the sustain electrode Z which is a common electrode, and a ground voltage 0 [V] is applied to the address electrode X. When a ramp-down waveform is applied to the sustain electrode Y, an erase discharge occurs between the scan electrode Y and the sustain electrode Z. This erase discharge erases excess wall charges unnecessary for the address discharge among the wall charges generated during the setup period.

In the address period, the scan pulse (-SP) is sequentially applied to the scan electrodes (Y) and the data pulse (DP) is applied to the address electrodes (X) in synchronization with the scan pulse (-SP). As the voltage difference between the scan pulse -SP and the data pulse DP and the wall voltage due to the wall charge generated during the reset period are added, an address discharge is generated in the cell to which the data pulse DP is applied. In the cells selected by the address discharge, wall charges such that discharge can occur when the sustain voltage Vs is applied are formed.

On the other hand, the sustain electrode Z is supplied with a positive DC voltage so as to reduce the voltage difference between the scan electrode Y during the set-down period and the address period so as to prevent erroneous discharge from the scan electrode Y.

In the sustain period, sustain pulses SuPy and SusPz are applied to the scan electrodes Y and the sustain electrodes Z alternately. The cell selected by the address discharge is sustained between the scan electrode (Y) and the sustain electrode (Z) whenever the sustain pulses (SusPy, SusPz) are applied as the wall voltage and the sustain pulses (SusPy, SusPz) voltages are added. Discharge, that is, display discharge (oil aliphatic), occurs.

In the erasing period, a ramp waveform ES having a small pulse width and a low voltage level is supplied to the sustain electrode Z to erase the wall charge remaining in the cells turned on by the sustain discharge.

In the selective write (SW) driving method, sufficient wall charges are formed in the discharge cells only when the pulse width of the scan pulse supplied to the scan electrode Y is set to about 3 us or more in the address period. For this reason, in the selective write (SW) method, a large amount of time is taken as an address period, and thus the sustain (maintenance) period is relatively reduced, resulting in low luminance. Furthermore, when the high resolution image is implemented by the selective write (SW) driving method, the address period is further increased, and gray scale is impossible due to the lack of the sustain period.

In order to solve these problems, a selective erase (SE) driving method has been proposed.

4 is a frame configuration diagram of a plasma display panel using a selective erasing method.

Referring to FIG. 4, each subfield of the selective erase (SE) method is divided into a reset period, an address period, and a sustain period.

After all cells are turned on by the front lighting discharge in the reset period, the cells are selectively erased and discharged in the address period to turn off. Subsequently, in the sustain period, images are displayed by causing the discharge cells not selected in the address period to maintain the discharge. For example, in the case where an image is to be displayed with 265 gray levels, one frame period (16.67 ms) corresponding to 1/60 second is divided into eight subfields SF1 to SF8. Each of the eight subfields is divided into a reset period, an address period, and a sustain period. The reset period and the address period of each subfield are the same for each subfield, while the sustain period and the number of discharges thereof are 2 ⁿ in each subfield (where n = 0, 1, 2, 3, 4, 5, 6, 7) is increased in proportion. As such, gray scales can be implemented by combining subfields having different sustain periods.

Since the selective erasing (SE) method selects the discharge cells for the erase discharge in the address period, the scan pulse width can be reduced compared to the selective write method, thereby reducing the address period. The luminance can be improved by increasing the sustain period by the time remaining by reducing the address period.

5 is a waveform diagram illustrating a driving waveform of the plasma display panel according to the selective erasure driving method.

Referring to FIG. 5, eight subfields SF1 to SF8 included in one frame of the conventional plasma display panel generate reset discharges in all discharge cells of the plasma display panel, thereby turning on the discharge cells. The driving period is divided into a reset period for generating a sustain period, an address period for selectively turning off the discharge cells turned on in the reset period, and a sustain period for causing sustain discharge in discharge cells not selected in the address period.

The reset period is divided into a front writing period in which the lamp pulses RPy and -RPz are applied to the scan electrode Y and the sustain electrode Z, and a sustain pulse period in which the sustain pulses Py and Pz are applied.

During the front lighting period, the positive polarity (+) lamp pulse (RPy) is supplied to the scan electrode (Y), the negative electrode pulse (-RPz) is supplied to the sustain electrode (Z), and the address electrode ( The ground potential GND is supplied to X). Here, the peak value of the ramp pulse RPy of positive polarity (+) is set to the same voltage as the sustain voltage Vs. Further, the peak absolute value of the negative pulse pulse (-RPz) is set to an absolute voltage greater than the sustain voltage Vs. (I.e., | Vs | <| -Vz |) The positive polarity (+) lamp pulse (RPy) is supplied to the scan electrode (Y) during the entire front lighting period, and the negative (-) is applied to the sustain electrode (Z). When the lamp pulse of -RPz is supplied, a reset discharge is generated in all the discharge cells by the voltage difference between the scan electrode Y and the sustain electrode Z, so that all the discharge cells are turned on.

When the reset discharge is generated during the front lighting period, a negative wall charge is formed on the scan electrode Y to which the positive positive pulse pulse RPy is supplied, and a negative negative pulse pulse is formed. Positive (+) wall charges are formed on the sustain electrode Z supplied with (-RPz).

In the sustain pulse period, the first stabilization pulse Pz is supplied to the sustain electrode Z, and then the second stabilization pulse Py is supplied to the scan electrode Y. At this time, the voltage values of the first stabilization pulse Py and the second stabilization pulse Pz are set equal to the sustain voltage Vs. Therefore, sustain discharge is generated between the scan electrode Y and the sustain electrode Z by the difference in the sustain voltage Vs between the scan electrode Y and the sustain electrode Z, so that uniform wall charges are formed in all the discharge cells. do.

In the address period, scan pulses (-SP) are sequentially supplied to the scan lines (Y), and data pulses (DP) synchronized with the scan pulse (-SP) are supplied to the address electrodes (X). Accordingly, in the discharge cells supplied with the data pulse DP, an address discharge, that is, an erase discharge occurs, and the wall charges in the discharge cell are erased. At this time, the wall charges formed in the reset period are sufficiently maintained in the discharge cells in which the erase discharge has not occurred.

In the sustain period, sustain pulses SuPy and SusPz are applied to the scan electrodes Y and the sustain electrodes Z alternately. Accordingly, sustain discharge occurs in discharge cells in which wall charges are not erased in the address period. In this case, the gray level value corresponding to the luminance weight is expressed by adjusting the number of sustain discharges.

6 is a diagram illustrating a duty ratio of waveforms applied to a sustain period according to the method of driving a plasma display panel.

Referring to FIG. 6, in a method of displaying an image on a plasma display panel, one frame is divided into a plurality of subfields to express a specific gray level, and each subfield is divided into a reset period, an address period, and a sustain period. Each subfield has a sustain period corresponding to a predetermined luminance weight, and a combination of these subfields represents a desired gray scale value.

The gradation value expressed in the sustain period is determined by the number of discharges in the sustain period. In order to cause such a discharge, a sustain pulse (holding pulse) should be applied to the scan electrode Y and the sustain electrode Z alternately during the sustain period.

These sustain pulses have periods t (i) Sus_cycle and t (j) Sus_cycle, and each period has a period (t (i) Sus_ON, t (j) Sus_ON) to which the sustain pulses are applied and a sustain pulse is not applied. The period is divided into t (i) Sus_OFF and t (j) Sus_OFF. In order for the sustain discharge to occur stably, the periods (t (i) Su_ON and t (j) Sus_ON) to which the sustain pulses are applied in the sustain pulse period should be sufficient. The relative ratio of the ON time and the OFF time of the sustain pulse is referred to as duty.

This duy is represented by the following equation.

In general, a driving method of a plasma display panel is a duty of a subfield representing a low luminance weight (eg, a first subfield) and a subfield representing a high luminance weight (eg, an eighth subfield). Is set to be equal. For example, in the i-th subfield with low luminance weight and the j-th subfield with high luminance weight, the period ON for applying the sustain pulse and the period OFF for not applying the sustain pulse are set to be the same. Further, the periods of the sustain pulses (t (i) Sus-cycle, t (j) Sus-cycle) are set to be the same.

  The relationship between the sustain pulse periods is expressed by the following equation.

Here, t (i) Sus_cycle is a sustain pulse period in a subfield indicating low luminance weight, and t (j) Sus_cycle is a sustain pulse period in a subfield indicating high luminance weight.

Recently, various attempts have been made to increase contrast, which is one of important factors for determining the image quality of plasma display panels. One method is to increase the frequency of discharge by increasing the sustain frequency within the sustain period to increase the peak brightness. However, this method does not increase the sustain frequency much because the sustain period is limited in one frame.

In addition, unlike the total load calculation method in which weights are simply calculated according to gray scale values of each display cell, even if the corresponding gray scale value of the display cells is low, the driving margin is determined according to how much area is displayed in the frame. margins vary. As illustrated in FIG. 7, when a low gray scale value is expressed in a large area, the gray scale value is expressed by sustain discharge of a subfield expressing a relatively low luminance weight among a plurality of subfields. However, if the period and duty of the sustain pulse are not sufficient in the sustain period of such a subfield, the discharge will not occur and the driving margin will deteriorate sharply. Therefore, the display discharge cannot be stably displayed on the area independently of the total accumulated data volume. Poor reliability In addition, depending on the panel state, there is a high possibility of false discharge occurring locally or entirely.

As described above, in the general plasma display panel driving method, sustain discharge is performed by fixing the period and duty value of the sustain pulse in all subfields of one frame. Using this method, it is difficult to generate stable sustain discharge in a subfield expressing low luminance weight when a low gray scale value is to be expressed in a large area, resulting in poor driving margin and poor reliability.

In addition, when trying to express a high gradation value, a large number of sustain discharges cannot be generated in a subfield expressing a high brightness weight, resulting in poor display quality.

Accordingly, there is a need for a method and apparatus for driving a plasma display panel that can generate stable sustain discharge in a subfield expressing a low brightness weight and generate many sustain discharges in a subfield expressing a high brightness weight. .

Accordingly, it is an object of the present invention to provide a method and apparatus for driving a plasma display panel which can improve display quality and reliability.

In order to achieve the above object, the plasma display panel driving method according to the present invention divides one frame period into a plurality of subfields, and time-divisionally drives each subfield into a reset period, an address period and a sustain period to display an image. A method of driving a display panel, the method comprising: varying a duty value of a sustain pulse applied in the sustain period according to a weight of the subfield; The duty value is reduced as the subfield expressing the high luminance weight among the subfields. The low weight subfield is driven ahead of the high weight subfield; The pulse width is increased as a subfield representing a low luminance weight among the subfields. The duty value is increased as the subfield expressing the low luminance weight among the subfields. The number of pulses applied to the subfield representing the high brightness weight is increased by decreasing the pulse width in the subfield representing the high brightness weight. The pulse width applied to the subfield expressing the low luminance weight is increased by decreasing the pulse width in the subfield expressing the high luminance weight. As the subfield expressing the high luminance weight among the subfields, the pulse period time is reduced. The pulse period time is increased as a subfield expressing a low luminance weight among the subfields. The pulse cycle time applied to the subfield representing the low luminance weight is increased by decreasing the pulse cycle time in the subfield representing the high luminance weight. The number of pulses applied to the subfield expressing the high brightness weight is increased by decreasing the pulse period time in the subfield expressing the high brightness weight. The driving apparatus of the plasma display panel divides one frame period into a plurality of subfields, and time-divisionally drives each subfield into a reset period, an address period, and a sustain period to display an image. The duty pulse is generated by varying the duty value of the sustain pulse applied in the sustain period according to the weight of the field, and means for reducing the duty value in the subfield expressing the high luminance weight among the subfields.

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Other objects and features of the present invention other than the above object will become apparent from the description of the embodiments with reference to the accompanying drawings.

Hereinafter, a method and apparatus for driving a plasma display panel according to the present invention will be described in detail with reference to FIGS. 8 to 10.

A method and apparatus for driving a plasma display panel according to the present invention include a selective write (SW) method, a selective erase (SE) method, and a selective write and erase (SE) combination of the above-described selective write (SW) method and selective erase (SE) method. It can be applied to both SWSE) methods.

Referring to FIG. 8, in the plasma display panel driving method, the gray value expressed in the sustain period is determined by the number of discharges in the sustain period. In order to cause such a discharge, a sustain pulse is applied to the scan electrode Y and the sustain electrode Z alternately during the sustain period.

These sustain pulses have periods (t (i) Sus-cycle, t (j) Sus-cycle), and each pulse period has no sustain pulses (t (i) Sus-ON, t (j) Sus-ON) and sustain pulses. Period (t (i) Sus_OFF, t (j) Sus_OFF).

In the method of driving the plasma display panel according to the first embodiment of the present invention, the duty value of the sustain waveform applied in the sustain period of the subfield expressing the low luminance weight and the subfield expressing the high luminance weight is set differently. .

In detail, the driving method of the plasma display panel according to the first exemplary embodiment of the present invention includes the period t of the sustain pulse applied to the j-th subfield (for example, the eighth subfield) expressing the high luminance weight. j) Decrease Sus_ON).

The number of sustain pulses applied to the subfield expressing the high luminance weight is increased by the time remaining by decreasing the period (t (j) Sus_ON) during which the sustain pulse of the j-th subfield expressing the high luminance weight is applied. Increasing the number of sustain pulses generates a large number of sustain discharges, which improves luminance.

In addition, the i-th subfield (for example, the first subfield) that expresses low gradation by the time remaining by decreasing the period (t (j) Sus_ON) to which the sustain pulse of the j-th subfield expressing the high luminance weight is applied. Increases the supply period t (i) Sus_ON of the sustain pulses applied thereto. As the sustain pulse supply period is increased, sustain discharge is generated more stably. When the sustain discharge is stably generated, the driving margin is increased to improve the reliability.

The duty of the sustain pulse applied to the subfield expressing the low luminance weight by this method is expressed by the following equation.

The duty of the sustain pulse applied to the subfills expressing the high luminance weight by this method is expressed by the following equation.

When the method according to the first embodiment of the present invention is applied, the duty of the sustain pulse applied to the subfield expressing the low luminance weight is equal to or greater than the duty of the sustain pulse applied to the subfield expressing the high luminance weight. Becomes

If this is expressed as an equation, it is expressed as follows.

9 is a diagram illustrating a frame structure and waveforms for explaining a method of driving a plasma display panel according to a second embodiment of the present invention.

In the driving method of the plasma display panel, the gray value expressed in the sustain period is determined by the number of discharges in the sustain period. In order to cause such a discharge, a sustain pulse (sustain pulse) should be applied to the scan electrode Y and the sustain electrode Z alternately during the sustain period.

These sustain pulses have periods (t (i) Sus-cycle, t (j) Sus-cycle), and each pulse period has no sustain pulses (t (i) Sus-ON, t (j) Sus-ON) and sustain pulses. Period (t (i) Sus_OFF, t (j) Sus_OFF).

In the method of driving the plasma display panel according to the second embodiment of the present invention, the period t of the sustain pulse applied to the sustain period of the i-th subfield representing the low luminance weight and the jth subfield representing the high luminance weight (t (i Set Sus_cycle, t (j) Sus_cycle) differently.

In detail, the period t (j) Sus_ON of the sustain pulse applied to the j-th subfield (for example, the eighth subfield) expressing the high luminance weight and the period t (j) where the sustain pulse is not applied Decreases SuS_OFF). By decreasing both the ON and OFF periods of the sustain pulse, the period t (j) Sus-cycle of the sustain pulse is reduced.

The number of sustain pulses applied to the subfield expressing the high luminance weight is increased by the time remaining by decreasing the sustain pulse period t (j) Sus-cycle of the j-th subfield expressing the high luminance weight. Increasing the number of sustain pulses generates a large number of sustain discharges, which improves luminance.

In addition, the sustain pulse in the subfield (eg, the first subfield) expressing the low luminance weight by the time remaining by decreasing the sustain pulse period t (j) Sus-cycle of the j-th subfield expressing the high luminance weight is sustained. The period in which t is applied (t (i) Sus_ON) and the period in which the sustain pulse is not applied (t (i) Sus_OFF) are increased. The duration of the sustain pulse period t (i) Sus-cycle is increased by increasing both the period t (i) Sus_ON during which the sustain pulse is applied and the period t (i) Sus_OFF where the sustain pulse is not applied.

In this way, sustain discharge is stably generated in the subfield expressing low brightness, and the driving margin is increased, thereby improving reliability.

According to the driving method of the plasma display panel according to the second embodiment of the present invention, the period (t (i) Sus_cycle) of the sustain pulse applied to the i subfield representing the low luminance weight is the j th representing the high luminance weight. It is equal to or greater than the period t (j) Sus_cycle of the sustain pulse applied to the subfield.

If this is expressed as an equation, it is expressed as follows.

10 is a block diagram showing the configuration of a plasma display panel device according to the present invention.

Referring to FIG. 10, the plasma display panel driving apparatus according to the present invention includes a data driver 55 for driving the address electrode X of the plasma display panel and a scan for driving the scan electrode Y of the plasma display panel. The driver 51, the sustain driver 53 for driving the sustain electrode Z of the plasma display panel, the timing controller 57 for controlling the driving timing of the plasma display panel, the scan driver 51 and the sustain. Pulse control switches 59 and 69 for controlling the sustain voltage applied to the driver 53, a gamma correction unit, an automatic gain control unit, an error diffusion unit, a data search unit, a subfield mapping unit, a frame memory, A data alignment unit for each drive IC is provided.

The data driver 55 is connected to a predetermined number of address electrodes X and includes a plurality of data drive ICs for supplying data to the address electrodes X.

The scan driver 51 is connected to the scan electrodes Y to supply a reset pulse (or setup pulse) to the scan electrodes Y at the same time. In addition, the scan driver 51 sequentially supplies the scan pulses to the scan electrodes Y in the address period, and then simultaneously supplies the sustain pulses to the scan electrodes Y in the sustain period.

The sustain driver 53 is commonly connected to the sustain electrodes Z to supply the sustain pulses to the sustain electrodes Z at the same time.

The timing controller 57 receives the vertical / horizontal synchronization signals H and V to generate a timing control signal, and supplies the timing control signal to the data driver 55, the scan driver 51, and the sustain driver 53. The driving timing of the plasma display panel is controlled. Further, the switch control signals tc1 and tc2 are generated and supplied to the pulse control switches 59 and 69 connected to the scan electrode Y and the sustain electrode Z, respectively, to scan electrode Y and the sustain electrode Z. Control the sustain pulse applied to).

The pulse control switches 59 and 69 are connected to the scan electrode Y and the sustain electrode Z in accordance with the switch control signals tc1 and tc2 generated from the timing controller 57 and the sustain electrode. The sustain pulse supplied to the electrode Z is controlled. These switch control signals tc1 and tc2 are applied to each of the pulse control switches 59 and 69 alternately with each other.

In detail, when the switch control signal tc1 generated from the timing controller 57 is supplied to the pulse control switch 59 connected to the scan driver 51, the pulse control switch 59 is turned on. -On). When the pulse control switch 59 is turned on, the sustain voltage Vs is supplied to the scan driver 51, and a sustain pulse is applied to the scan electrode Y. Thereafter, when the switch control signal tc1 is not supplied to the pulse control switch 59, the pulse control switch 59 is turned off. When the pulse control switch 59 is turned off, the sustain voltage Vs is not supplied to the scan driver 51, so that the sustain pulse is not applied to the scan electrode Y.

On the other hand, when the switch control signal tc2 generated from the timing controller 57 is supplied to the pulse control switch 69 connected to the sustain driver 53, the pulse control switch 69 is turned on. do. When the pulse control switch 69 is turned on, the sustain voltage Vs is supplied to the sustain driver 53 so that a sustain pulse is applied to the sustain electrode Z. Thereafter, when the switch control signal tc2 is not supplied to the pulse control switch 69 (Off), the pulse control switch 69 is turned off. When the pulse control switch 69 is turned off, the sustain voltage Vs is not supplied to the sustain driver 53, so that a sustain pulse is not applied to the sustain electrode Z.

The sustain pulse periods t (i) Sus-cycle, t (j) Sus-cycle and duty (Duty (i), Duty (j)) applied to the scan electrode (Y) and the sustain electrode (Z) correspond to the scan electrode (Y). It is controlled by the switch control signals tc1 and tc2 supplied to the pulse control switches 59 and 69 connected to the sustain electrode Z.

As described above, the method and apparatus for driving the plasma display panel according to the exemplary embodiment of the present invention may set the duty value of the sustain pulse applied in the sustain period and the sustain pulse period differently. In this way, the discharge is stably generated in the subfield expressing the low luminance weight to increase the driving margin to improve reliability, and in the subfield expressing the high luminance weight, the number of pulses is increased to generate a large number of discharges, thereby improving luminance. . As a result, the display quality of the plasma display panel can be improved.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

1 is a perspective view showing a discharge cell structure of a three-electrode AC surface discharge type plasma display panel.

2 is a frame configuration diagram of a plasma display panel using a selective writing method.

3 is a waveform diagram illustrating a driving waveform of the plasma display panel according to the selective writing method.

4 is a frame configuration diagram of a plasma display panel using a selective erasing method.

5 is a waveform diagram illustrating a driving waveform of the plasma display panel according to the selective erasing method.

6 is a diagram illustrating a duty ratio of waveforms applied to a sustain period according to the method of driving a plasma display panel.

7 is a diagram illustrating a data load distribution according to a screen displayed on a plasma display panel.

8 is a diagram illustrating a frame structure and waveforms for explaining a method of driving a plasma display panel according to a first embodiment of the present invention.

9 is a diagram illustrating a frame structure and waveforms for explaining a method of driving a plasma display panel according to a second embodiment of the present invention.

10 is a block diagram showing the configuration of a plasma display panel device according to the present invention.

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

10: upper substrate 18: lower substrate

Y: scan electrode Z: sustain electrode

X: address electrode 12Y, 12Z: transparent electrode

13Y, 13Z: metal bus electrode 14: upper dielectric layer

16: protective film 22: lower dielectric layer

24: partition 26: phosphor layer

51: scan drive unit 53: sustain drive unit

55: data driver 57: timing controller

59,69: pulse control switch

Claims (25)

delete delete delete A driving method of a plasma display panel in which a frame period is divided into a plurality of subfields and time-division driving of each subfield into a reset period, an address period, and a sustain period is displayed. Varying the duty value of the sustain pulse applied in the sustain period according to the weight of the subfield; And a duty value is reduced as a subfield expressing a high brightness weight among the subfields. The method of claim 4, wherein The low weight subfield is driven ahead of the high weight subfield; And the pulse width is increased as a subfield expressing a low luminance weight among the subfields. The method of claim 5, And a duty value of the subfield representing the low luminance weight among the subfields is increased. The method of claim 4, wherein And increasing the number of pulses applied to the subfield expressing the high brightness weight by decreasing the pulse width in the subfield expressing the high brightness weight. The method of claim 6, And increasing the pulse width applied to the subfield expressing the low brightness weight by decreasing the pulse width in the subfield expressing the high brightness weight. The method of claim 4, wherein And the pulse cycle time is reduced as a subfield expressing a high luminance weight among the subfields. The method of claim 9, And the pulse cycle time is increased as a subfield expressing a low luminance weight among the subfields. The method of claim 10, And increasing the pulse cycle time applied to the subfield expressing the low luminance weight by decreasing the pulse cycle time to the subfield expressing the high luminance weight. The method of claim 10, And increasing the number of pulses applied to the subfield expressing the high brightness weight by decreasing the pulse cycle time in the subfield expressing the high brightness weight. delete delete delete delete A driving apparatus of a plasma display panel for dividing a frame period into a plurality of subfields and time-division driving each subfield into a reset period, an address period, and a sustain period to display an image. And a means for generating the sustain pulse by varying the duty value of the sustain pulse applied in the sustain period according to the weight of the subfield, and reducing the duty value as the subfield expressing the high luminance weight among the subfields. A drive device for a plasma display panel. The method of claim 17, The low weight subfield is driven ahead of the high weight subfield; And the pulse width is increased as a subfield expressing a low luminance weight among the subfields. The method of claim 17, And a duty value of the subfield representing the low luminance weight in the subfield increases. The method of claim 16, And increasing the number of pulses applied to the subfield expressing the high brightness weight by decreasing the pulse width in the subfield expressing the high brightness weight. The method of claim 17, And increasing the pulse width applied to the subfield expressing the low brightness weight by decreasing the pulse width in the subfield expressing the high brightness weight. The method of claim 17, And the pulse cycle time is reduced as a subfield expressing a high luminance weight among the subfields. The method of claim 22, And the pulse cycle time is increased as a subfield expressing a low luminance weight among the subfields. The method of claim 23, wherein And increasing the pulse cycle time applied to the subfield representing the low luminance weight by decreasing the pulse cycle time to the subfield representing the high luminance weight. The method of claim 23, wherein And increasing the number of pulses applied to the subfield expressing the high brightness weight by decreasing the pulse cycle time in the subfield expressing the high brightness weight.