KR20040068049A - A plasma display panel driving apparatus and the driving method which improves characteristics of an address period - Google Patents

Abstract

PURPOSE: An apparatus and a method for driving a plasma display panel with an improved address section characteristics are provided to improve stability of an image by changing an end portion of a bias applied to a panel. CONSTITUTION: An analog image signal to be displayed on a panel is converted into digital data to be recorded in a frame memory(100). A frame generator(200) divides the digital data stored in the frame memory upon outputting it to a driving pulse generator(400). A timing controller(300) generates all sorts of timing signals required for the operation of the frame generator and the driving pulse generator. The driving pulse generator receives a frame generating signal and a timing signal outputted from the frame generator and the timing controller to scan a scan electrode driver(600) and a common electrode driver(700) and to generate an address signal for driving an address electrode driver(500). The driving pulse generator generates a signal wave form to apply to each electrode in a reset period, a scan period, and a sustain period.

Description

Plasma display panel driving device with improved address section characteristics and driving method thereof {A PLASMA DISPLAY PANEL DRIVING APPARATUS AND THE DRIVING METHOD WHICH IMPROVES CHARACTERISTICS OF AN ADDRESS PERIOD}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel, and in particular, by modifying the last part of the bias applied to the panel, thereby widening the operating margin of the panel by the bias, thereby improving the address interval characteristic to stably express the image represented on the panel. A plasma display panel drive device and a driving method thereof.

In general, a plasma display panel (PDP) is a flat panel display device that displays characters or images by using plasma generated by gas discharge, and a matrix of tens to millions or more of pixels is matrixed according to its size. The plasma display panel is divided into a direct current type (DC type) and an alternating current type (AC type) according to the shape of a driving voltage waveform to be applied and the structure of a discharge cell.

The structural difference between the direct current type and the direct current type is that in the direct current type, the electrode is exposed to the discharge space as it is, so that the current flows in the discharge space while the voltage is applied. Therefore, there is a disadvantage in that the resistance for current limitation must be made externally. On the other hand, in the case of the AC type, the dielectric layer covers the electrode so that the current is limited by the natural capacitive formation, and the life is longer than that of the DC type because the electrode is protected from the impact of ions during discharge. The memory characteristic, which is one of the important characteristics of the AC plasma display panel, also comes from the capacitive property of the dielectric layer covering the electrode.

In the light emission principle of the AC plasma display panel, a pulse type potential difference is formed between the common electrode (or the X electrode and the sustain electrode) and the scan electrode (or the Y electrode and the scan electrode) to generate a discharge. As ultraviolet rays are excited to phosphors of red (R), green (G), and blue (B), each phosphor emits light by light combination. These discharges are affected by various parameters, but they are largely related to the discharge gas type and pressure inside the plasma display panel, and the secondary electron emission characteristics of the magnesium oxide (MgO) protective film. It depends a lot.

In the AC plasma display panel, since the sustain (common) electrode and the scan (scan) electrode for the sustain discharge act as capacitive loads, capacitance (Cp) exists for the X electrode and the Y electrode, and the waveform for the sustain discharge is shown. In order to apply, reactive power is required in addition to power for discharging.

1 is an electrode arrangement diagram of a typical plasma display panel.

The electrodes have a matrix configuration of m columns X n rows. Address electrodes A1 to Am are arranged in the column direction, and n rows of scan electrodes SCN1 to SCNn and common electrodes SUS1 to SUSn are arranged in the row direction. The discharge space at the intersection of the address electrode, the paired scan electrode, and the common electrode forms a discharge cell.

2 is a waveform diagram showing a conventional plasma display panel driving waveform.

In order to generate a driving waveform of a conventional plasma display panel, the driving device includes one or more switches according to an operation sequence, and supplies power to the panel according to the switching operation of the switch, and recovers the power again after discharge is performed. A pulse supply unit (not shown) for generating a drive waveform generates a reset pulse for initializing the state of each discharge cell, stores a pulse signal for allowing wall charges to accumulate in the discharge cell, and stores the pulse signal on the panel at a predetermined timing. The stored pulses are output, and each discharge cell is selected to address and discharge cells to be turned on and discharge cells not to be turned on.

In the conventional plasma display panel driving method, one frame includes n subfields, and one subfield includes a reset period, a scan period, and a sustain period.

As shown in FIG. 2, in the reset period, all address electrodes A1 to Am and all sustain electrodes SUS1 to SUSn are held at 0 V in all the reset periods, and all scan electrodes SCN1 to SCNn are connected to each other. A ramp voltage that rises smoothly from the voltage below the discharge start voltage to the voltage above the discharge start voltage is applied to the sustain electrode. In the second half of the reset period, ramp voltages that slowly drop toward the 0 V over the discharge start voltage are applied to all the scan electrodes from the voltage which is below the discharge start voltage.

In the scan (address) section, all the Y electrodes are held at the voltage Vsc, and a positive scan pulse voltage is applied to the address electrode corresponding to the discharge cell to be displayed on the first row of the addressing electrodes, and a scan pulse voltage is applied to the Y electrode of the first row. 0 V) is applied simultaneously to allow wall charge to accumulate.

In the sustain (sustain) section, a predetermined sustain pulse is applied to all the Y electrodes and the X electrodes so that sustain discharge occurs at a gray scale to be expressed in the discharge cell.

In the erase period, a predetermined erase pulse is applied to all the X electrodes to stop the sustain discharge.

In such a conventional plasma display panel driving method (particularly, an address-display separation (ADS) driving method), the purpose of address discharge is to select a discharge cell in which sustain discharge will occur in an address period and a discharge cell in which it will not. The condition that the address discharge is to be satisfied is that the address discharge occurs precisely within a given address period, and the wall charge structure advantageous for the sustain discharge is produced to perform the sustain discharge.

X electrode biasing within the scan period plays an important role in making a wall charge structure capable of sustain discharge to address discharge. In other words, the wall charge structure is formed so that the discharge is generated between the X electrode and the Y electrode by using the address discharge of the Y electrode as a trigger to generate a large amount of wall charge between the X electrode and the Y electrode. Form or attract electrons to the X electrode. Therefore, the higher the X electrode biasing voltage, the higher the operating margin.

However, in the conventional plasma display panel driving method, when the X electrode biasing voltage is excessively high, a large amount of electrons accumulate on the X electrode and a voltage due to wall charge is formed, so that the X electrode biasing is at ground (GND) level or reference. There is a problem in that an incorrect discharge occurs in the last part falling to the voltage. In other words, the higher the X electrode biasing voltage, the more electrons accumulate on the X electrode, and a discharge occurs when the X electrode biasing voltage drops to the ground level or the reference voltage. This discharge prevents or sustains the next sustain discharge. There is a problem of weakening the discharge.

In order to solve this problem, the technical problem of the present invention is to improve the driving voltage applied to the common electrode in the address period by modifying the last part of the bias falling to the ground level or the reference voltage, the operation of the common electrode bias The purpose is to widen the margin so that the image displayed on the plasma display panel can be stably represented.

1 is an electrode arrangement diagram of a typical plasma display panel.

2 is a waveform diagram showing a conventional plasma display panel driving waveform.

3 is a diagram illustrating a plasma display panel driving apparatus having improved characteristics of an address section according to a first embodiment of the present invention.

4 is a waveform diagram illustrating a driving waveform of a plasma display panel with improved characteristics of an address section according to a first embodiment of the present invention.

5 is a waveform diagram illustrating driving waveforms of a plasma display panel with improved characteristics of an address section according to a second exemplary embodiment of the present invention.

6 is a waveform diagram illustrating driving waveforms of a plasma display panel having improved characteristics of an address section according to another example of the second exemplary embodiment of the present invention.

FIG. 7 is a waveform diagram illustrating driving waveforms of a plasma display panel with improved characteristics of an address section according to another example of the second exemplary embodiment of the present invention.

FIG. 8 is a waveform diagram illustrating driving waveforms of a plasma display panel having improved characteristics of an address section according to another example of the second exemplary embodiment of the present invention.

9 is a waveform diagram illustrating driving waveforms of a plasma display panel with improved characteristics of an address section according to a third exemplary embodiment of the present invention.

In order to achieve the above object, the present invention provides a first drive of the sustain discharge or falls with at least one constant slope while the common electrode bias falls to the ground level or the reference voltage in order to prevent the sustain discharge from being affected by the initial discharge. Overlap the pulse.

In order to achieve the above object, there is provided a driving apparatus of a plasma display panel in which an address section characteristic is improved.

A driving device of a plasma display panel including a plurality of address electrodes and a plurality of scan electrodes and sustain electrodes paired with one another in pairs,

An address electrode driver for processing an address signal and applying the same to one or more of the address electrode lines;

A sustain / scan pulse generator configured to sequentially scan one or more of the scan electrodes, generate scan pulses and sustain pulses, and apply them to the scan electrodes and the sustain electrodes to form wall charges;

The sustain / scan pulse generator is configured to maintain the voltage of the sustain electrode as a first voltage in an address section, and to apply the first sustain discharge pulse to the scan electrode in a sustain section, during the initial part of the section of the sustain electrode. The voltage is maintained at the first voltage.

According to another aspect of the present invention, there is provided a driving apparatus of a plasma display panel having improved address range characteristics

A driving device of a plasma display panel including a plurality of address electrodes and a plurality of scan electrodes and sustain electrodes paired with one another in pairs,

An address electrode driver for processing an address signal and applying the same to one or more of the address electrode lines; A sustain / scan pulse generator configured to sequentially scan one or more of the scan electrodes, generate scan pulses and sustain pulses, and apply them to the scan electrodes and the sustain electrodes to form wall charges;

The sustain / scan pulse generation unit maintains the voltage of the sustain electrode as the first voltage in the address period, and applies the voltage of the sustain electrode to the first voltage before applying the first sustain discharge pulse to the scan electrode in the sustain period. Gradually lowering to the second voltage at.

According to another aspect of the present invention, there is provided a method of driving a plasma display panel with improved address interval characteristics.

A driving method of a plasma display panel including a plurality of address electrodes and a plurality of scan electrodes and sustain electrodes paired with one another in pairs,

A reset step of initializing a charge distribution state of the discharge cells formed by the address electrode, the scan electrode, and the sustain electrode;

A scan step of determining on and off of the discharge cells and addressing them; And

A sustain discharge step of sustain discharge of the addressed discharge cells;

The sustain electrode voltage is maintained at the first voltage in the addressing step, and the voltage of the sustain electrode is changed during the initial part of the period in which the first sustain discharge pulse is applied to the scan electrode in the sustain discharge step. It is characterized by maintaining the voltage.

According to another aspect of the present invention, there is provided a method of driving a plasma display panel with improved address interval characteristics.

A driving method of a plasma display panel including a plurality of address electrodes and a plurality of scan electrodes and sustain electrodes paired with one another in pairs,

A reset step of initializing a charge distribution state of a discharge cell formed by the address electrode, scan electrode, and sustain electrode;

A scan step of determining on and off of the discharge cells and addressing them; And

A sustain discharge step of sustain discharge of the addressed discharge cells;

In the addressing step, the voltage of the sustain electrode is maintained at the first voltage, and the voltage of the sustain electrode is changed from the first voltage to the second voltage before the first sustain discharge pulse is applied to the scan electrode in the sustain discharge step. It is characterized by gradually descending.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a diagram illustrating a plasma display panel driving apparatus having improved characteristics of an address section according to a first embodiment of the present invention.

As shown in FIG. 3, the plasma display panel driving apparatus having improved characteristics of the address section according to the first embodiment of the present invention includes a frame memory unit 100, a frame generator 200, a timing controller 300, The driving pulse generator 400, the address electrode driver 500, the scan electrode driver 600, the common electrode driver 700, and the panel 800 are included.

The analog image signal to be displayed on the panel 800 is converted into digital data and recorded in the frame memory 100.

The frame generator 200 divides digital data stored in the frame memory 100 as necessary and outputs the divided digital data to the driving pulse generator 400. For example, in order to display gray scales, the panel 800 divides one frame of pixel data stored in the frame memory 100 into a plurality of subfields according to the gray scale level, and outputs data of each subfield.

The timing controller 300 generates various timing signals necessary for the operation of the frame generator 200 and the driving pulse generator 400.

The driving pulse generator 400 receives the frame generation signal and the timing signal output from the frame generator 200 and the timing controller 300, and scans the scan electrode driver 600 and the common electrode driver 700. An address signal for driving the driver 500 is generated, and a signal waveform to be applied to each electrode is generated in the reset period, the scan period, and the sustain period. That is, the driving pulse generator 400 generates a reset signal for initializing the state of each discharge cell, generates an address signal for selecting and addressing a discharge cell that is turned on and a discharge cell that is not turned on, and discharges the addressed cell. Generate a hold signal.

Hereinafter, the operation of the plasma display panel and the method of driving the plasma display panel by the operation of the driving apparatus according to the first embodiment of the present invention will be described in detail with reference to the accompanying drawings.

4 is a waveform diagram illustrating a driving waveform of a plasma display panel with improved characteristics of an address section according to a first embodiment of the present invention.

One frame includes a plurality of subfields, and each subfield includes a reset period, an address period, and a sustain period. The present invention may be applied to a case in which the present invention has a subfield structure of a frame as in the embodiment. The invention is not limited only to the examples.

The reset section is a section in which the wall charge distribution is adjusted to smoothly perform the write operation in the address section by forming wall charges with appropriate polarities and amounts in the address electrodes, the scan electrodes, and the common electrodes, respectively. That is, the wall charge state of each electrode is a section in which the charge state of the discharge cell is adjusted so that write discharge in the address section can be performed. The reset operation in the case where the reset period is performed immediately after the sustain discharge is performed in one subfield is a ramp in which the driving pulse generator 400 slowly rises to the common electrode when the sustain discharge in the previous subfield is completed. Apply a pulse. At this time, in the discharge cell that caused the sustain discharge, the inter-surface voltage on the scan electrode and the common electrode is obtained by adding the lamp voltage to the negative wall charge on the scan electrode and the positive wall charge on the common electrode appearing at the end of the sustain period. It becomes. The driving pulse generator 400 applies a ramp pulse to the common electrode, applies a square wave reset pulse to the first half of the reset section, and applies a ramp pulse that decreases linearly to the second half.

The drive pulse generator 400 maintains all the scan electrodes at the scan voltage Vsc and scans the positive scan pulse voltages to the address electrodes corresponding to the discharge cells to be displayed on the first row of the addressing electrodes in the scan period. The scan pulse voltage (0 V) is simultaneously applied to the scan electrodes of to allow wall charge to accumulate. At this time, an X electrode bias higher than the sustain discharge voltage Vs is applied to the common electrode.

The X bias in the scan period draws electrons generated by the address discharge onto the common electrode, thereby helping to smoothly discharge in the first pulse of the next sustain discharge period. That is, the discharge between the address electrode and the scan electrode causes the positive wall charges to the scan electrode and the electrons to the address electrode to be drawn to the common electrode by the X bias, so that the first sustain discharge pulse on the scan electrode side is followed. It becomes easy to occur. Therefore, when the X bias is higher than the sustain discharge voltage Vs, the probability of transition to sustain discharge is increased even if the address discharge by the address electrode-scan electrode does not occur strongly. This characteristic serves to increase the probability of transition to sustain discharge in case of performing a high-speed address or in the case where address discharge occurs in the absence of scan priming.

After the scan period ends and the sustain discharge period begins, the driving pulse generator 400 drops after applying the first sustain discharge pulse of the scan electrode before dropping the X electrode bias of the common electrode to the ground level or the reference voltage. Drop. This makes it possible to use the discharge generated by falling to the ground level or the reference voltage at a predetermined or more X bias as a sustain discharge, thereby improving the unnecessary discharge problem and widening the operating margin of 10 to 20 V than conventionally. Can be.

5 is a waveform diagram illustrating driving waveforms of a plasma display panel with improved characteristics of an address section according to a second exemplary embodiment of the present invention.

The driving device of the plasma display panel having improved characteristics of the address section according to the second embodiment of the present invention will be described by using the same reference numerals as the driving device of the first embodiment of the present invention. Hereinafter, the first embodiment of the present invention will be described. Descriptions of overlapping parts will be omitted.

In the second embodiment of the present invention, in order to lower the X bias to the ground level or the reference voltage, the driving pulse generator 400 causes the common bias to drop the X bias of the common electrode. By doing so, it is possible to reduce excessive wall charges on the common electrode through the weak discharge to an appropriate level. This driving method has an effect of increasing the conventional X bias by 30 V or more. At this time, in the embodiment of the present invention, although the X bias is dropped by the same slope as the slope of the falling ramp waveform applied in the reset period, the present invention is not limited only to the embodiment, and weak discharge by wall charge may be performed. You can also adjust the slope under conditions. However, in the plasma display panel driving method according to the second embodiment of the present invention, there is a problem in that the falling time of the X bias should take about 80 microseconds.

6 is a waveform diagram illustrating driving waveforms of a plasma display panel having improved characteristics of an address section according to another example of the second exemplary embodiment of the present invention.

As shown in FIG. 6, the driving pulse generator 400 rapidly lowers the voltage Vx to a voltage Vx that does not affect the operating state inside the panel 800 so as to reduce the fall time of the X bias. And drop it to ground level or reference voltage.

FIG. 7 is a waveform diagram illustrating a driving waveform of a plasma display panel having improved characteristics of an address section according to another example of the second exemplary embodiment of the present invention, and FIG. 8 illustrates an address according to another example of the second exemplary embodiment of the present invention. It is a waveform diagram which shows the drive waveform of the plasma display panel which improved the characteristic of a section.

As shown in FIG. 7, in order to reduce the amount of wall charge through the weak discharge, the driving pulse generator 400 is lowered to the ground level or the reference voltage in a log waveform after applying the X bias. In FIG. 8, in order to reduce the fall time of the X bias, the voltage 800 is quickly lowered to a voltage Vx which does not affect the operating state inside the panel 800, and then the waveform is in the form of a log, and the voltage falls to the ground level or the reference voltage. Let's do it.

9 is a waveform diagram illustrating driving waveforms of a plasma display panel with improved characteristics of an address section according to a third exemplary embodiment of the present invention.

The driving apparatus of the plasma display panel having improved characteristics of the address section according to the third embodiment of the present invention will be described using the same reference numerals as the driving apparatus of the first and second embodiments of the present invention. Descriptions of portions overlapping with the first and second embodiments will be omitted.

According to the third embodiment of the present invention, after the driving pulse generator 400 lowers the X bias to the ground level or the reference voltage, the first sustain discharge pulse of the scan electrode is held at a time within 1 μs. How to raise up.

Of course, the present invention is not limited to the embodiment as many modifications and variations can be made to the driving waveform of the plasma display panel without departing from the gist of the present invention.

As described above, the plasma display panel driving apparatus and the driving method which improve the characteristics of the address section of the present invention improves the driving voltage applied to the common electrode in the address section, thereby reducing the last part of the bias falling to the ground level or the reference voltage. By deforming, the operating margin of the common electrode bias is widened so that the image expressed on the plasma display panel can be stably expressed.

Claims (2)

In a driving apparatus of a plasma display panel including a plurality of address electrodes, a plurality of scan electrodes and a sustain electrode arranged in pairs with each other, An address electrode driver for processing an address signal and applying the same to one or more of the address electrode lines; A sustain / scan pulse generator configured to sequentially scan one or more of the scan electrodes, generate scan pulses and sustain pulses, and apply them to the scan electrodes and the sustain electrodes to form wall charges; The sustain / scan pulse generator, The voltage of the sustain electrode is maintained at the first voltage during an initial part of the period in which the voltage of the sustain electrode is maintained at the first voltage in the address period and the first sustain discharge pulse is applied to the scan electrode in the sustain period. doing An apparatus for driving a plasma display panel having improved characteristics of an address section. In a driving method of a plasma display panel comprising a plurality of address electrodes, a plurality of scan electrodes and a sustain electrode arranged in pairs with each other, A reset step of initializing a charge distribution state of a discharge cell formed by the address electrode, scan electrode, and sustain electrode; An addressing step of determining on and off of the discharge cells and addressing them; And A sustain discharge step of sustain discharge of the addressed discharge cells; The sustain electrode voltage is maintained at the first voltage in the addressing step, and the voltage of the sustain electrode is changed during the initial part of the period in which the first sustain discharge pulse is applied to the scan electrode in the sustain discharge step. Maintained with voltage A method of driving a plasma display panel having improved address interval characteristics.