KR100438909B1 - Method and Apparatus Driving of Plasma Display Panel - Google Patents

Abstract

The present invention relates to a method and apparatus for driving a plasma display panel, which automatically detects a control signal of an energy recovery device due to a malfunction of the plasma display panel and prevents damage to the driving device by automatically detecting it.

The method and apparatus for driving a plasma display panel according to the present invention integrate an switch control signal for controlling a switch element, output an integrated voltage of a DC voltageized switch control signal, and integrate the predetermined voltage and a predetermined reference value of the switch control signal. A control signal is generated by comparing voltages, and the driving of the energy recovery device is controlled in response to the control signal.

Description

Method and apparatus for driving plasma display panel {Method and Apparatus Driving of Plasma Display Panel}

The present invention relates to a plasma display panel, and in particular, when a control signal of an energy recovery apparatus does not occur due to a malfunction of the plasma display panel, a method of driving the plasma display panel to automatically detect and automatically prevent damage to the driving apparatus. And to an apparatus.

Plasma Display Panels (hereinafter referred to as "PDPs") display images containing characters or graphics by emitting phosphors by 147 nm ultraviolet rays generated during discharge of He + Xe or Ne + Xe inert mixed gases. . Such a PDP is not only thin and easy to enlarge, but also greatly improved in quality due to recent technology development. In particular, the three-electrode AC surface discharge type PDP has advantages of low voltage driving and long life because wall charges are accumulated on the surface during discharge and protect the electrodes from sputtering caused by the discharge.

Referring to FIG. 1, a discharge cell of a three-electrode AC surface discharge type PDP includes a scan electrode 12Y and a sustain electrode 12Z formed on an upper substrate 10, and an address electrode formed on a lower substrate 18. 20X). The upper dielectric layer 14 and the passivation layer 16 are stacked on the upper substrate 10 having the scan electrode 12Y and the sustain electrode 12Z side by side. Wall charges generated during plasma discharge are accumulated in the upper dielectric layer 14. The protective layer 16 prevents damage to the upper dielectric layer 14 due to sputtering generated during plasma discharge, and increases emission efficiency of secondary electrons. As the protective film 16, magnesium oxide (MgO) is usually used. The lower dielectric layer 22 and the partition wall 24 are formed on the lower substrate 18 on which the address electrode 20X is formed, and the phosphor 26 is coated on the surfaces of the lower dielectric layer 22 and the partition wall 24. The address electrode 20X is formed in the direction crossing the scan electrode 12Y and the sustain electrode 12Z. The partition wall 24 is formed in parallel with the address electrode 20X to prevent ultraviolet rays and visible light generated by the discharge from leaking to the adjacent discharge cells. The phosphor 26 is excited by ultraviolet rays generated during plasma discharge to generate visible light of any one of red, green, and blue. Inert gas for gas discharge is injected into the discharge space provided between the upper and lower plates and the partition wall.

Referring to FIG. 2, in the driving apparatus of the conventional AC surface discharge type PDP, m × n discharge cells 1 have scan electrode lines Y1 to Ym, sustain electrode lines Z1 to Zm, and address electrode lines. PDP 30 arranged in a matrix form so as to be connected to the electrodes X1 to Xn, a scan driver 32 for driving the scan electrode lines Y1 to Ym, and sustain electrode lines Z1 to Zm. The sustain driver 34 for driving the < RTI ID = 0.0 > and < / RTI > odd-numbered address electrode lines X1, X3, ..., Xn-3, Xn-1 and even-numbered address electrode lines X2, X4, ..., Xn-2, First and second address drivers 36A and 36B for dividing and driving Xn) are provided. The scan driver 32 sequentially supplies scan pulses and sustain pulses to the scan electrode lines Y1 to Ym so that the discharge cells 1 are sequentially scanned in line units, and m × n discharge cells are provided. (1) Let the discharge in each last. The sustain driver 34 supplies a sustain pulse to all of the sustain electrode lines Z1 to Zm. The first and second address drivers 36A and 36B supply image data to the address electrode lines X1 through Xn in synchronization with the scan pulse. The first address driver 36A supplies image data to the odd-numbered address electrode lines X1, X3, ..., Xn-3, Xn-1, and the second address driver 36B supplies the even-numbered address electrode lines ( Image data is supplied to X2, X4, ..., Xn-2, Xn).

In the AC surface discharge PDP thus driven, a high voltage of several hundred volts or more is required for the address discharge and the sustain discharge. Accordingly, in order to minimize the driving power required for the address discharge and the sustain discharge, an energy recovery device is added to the scan driver 32, the sustain driver 34, and the address drivers 36A and 36B. The energy recovery apparatus recovers the voltage charged between the scan electrode line (Y) and the sustain electrode line (Z) and the voltage charged between the address electrode lines (X) and reuses it as a driving voltage at the next discharge.

This energy recovery device is applied to the scan and sustain drives 32 and 34 shown in FIG. The scan and sustain drivers 32 and 34 to which the energy recovery device is applied are shown in detail with reference to the display panel as shown in FIG. 3. In FIG. 3, the scan driver 32 includes the third and fourth switches S3 and S4 and the inverter L connected in parallel to the panel capacitor Cp, and the first and the third connected in parallel to the inverter L. Common to the first and second switches S1 and S2 and the first and second switches S1 and S2 connected to the two diodes D1 and D2, the first and second diodes D1 and D2, respectively. Capacitor Css connected to is provided. In addition, the third switch S3 is connected to the external sustain voltage supply source Vcc, and the fourth switch S4 is connected to the ground GND. The panel capacitor Cp equivalently represents the capacitance formed between the scan electrode 12Y and the sustain electrode 12Z in the display panel 30 illustrated in FIG. 2. The holding driver 34, which is connected to the scan driver 32 with the panel capacitor Cp opposite to the scan driver 32, has the same configuration as the scan driver 32.

4 is a view for explaining a switching state of the operation of the energy recovery device shown in FIG.

3 and 4, assuming that the sustain pulse SSUS applied to the scan and sustain electrodes 12Y and 12Z in the sustain period SPD has a voltage charged to the external capacitor Css, first, t1. In the period of time, the first switch S1 is closed so that the voltage Vss charged in the external capacitor Css is charged in the panel capacitor Cp via the first switch S1 and the inductor L. The panel capacitor Cp is charged by closing the third switch S3 at the resonance point of the LC resonance waveform and supplying the external sustain voltage Vcc to the panel capacitor Cp for the period t2. At the time of discharging, the second switch S2 is first closed in the period t3 so that the voltage charged in the panel capacitor Cp is supplied to the external capacitor Css via the inductor L and the second switch S2, thereby providing an external capacitor. (Css) is charged. Next, in the t4 period, the second switch S2 is opened and the fourth switch S4 is closed so that the panel capacitor Cp is completely discharged. After the panel capacitor Cp maintains discharge for a predetermined period (approximately 1 mA), the scan driver 32 charges / discharges the panel capacitor Cp. As such, before the panel capacitor Cp is charged using the external sustain voltage Vcc, the panel capacitor Cp is supplied from the energy storage capacitor Css to supply the sustain voltage to the panel at a low voltage. do.

In the scan and sustain drives 32 and 34 based on the energy recovery device, the third switch S3 and the fourth switch S4 turn at the same time to be the most damaged by the malfunction during the sustain discharge operation. -On operation. That is, when the third switch S3 and the fourth switch S4 are turned on at the same time, the sustain voltage Vs and the ground GND caused by the external sustain voltage source Vcc are short-circuited, which leads directly to component damage. Will be.

Accordingly, in the related art, as shown in FIG. 5, a control signal for driving the third and fourth switches S3 and S4 is connected to the AND gate 40 to stop the operation of each driver 32 and 34. I use it.

Referring to FIG. 5, the driving apparatus of the PDP further includes an AND gate 40 in addition to the scan driver 32. Using the AND gate 40, the output according to the control signal is used as a signal for stopping the operation of the scan driver 32. This is carried out in the same configuration and operation in the holding drive 34 as well.

Referring to these operations, when the control signals of the third and fourth switches S3 and S4 are turned on at the same time, a high output is generated at the AND gate 40, and this high signal stops the operation of the driver. It acts to stop, preventing damage such as short circuit to ground. In addition, the control signals of the third and fourth switches S3 and S4 may not be generated. In this case, since the switch is not driven, the sustain pulse for sustain discharge does not occur, and problems such as component damage do not occur.

However, the control signals of the first and second switches S1 and S2 are different from those of the third and fourth switches S3 and S4. For example, even when the third and fourth switches S3 and S4 operate normally to generate a sustain pulse, the control signal of the first and second switches S1 and S2 is malfunctioned to control the energy recovery device. There are cases when no signal is generated. In this case, since the discharge is generated only by the sustain pulse of the high voltage without the energy recovery operation, there is a problem that an overcurrent is generated even in a short time, causing damage to the driving unit.

Accordingly, an object of the present invention is to provide a method and apparatus for driving a plasma display panel that automatically detects and corrects a control signal of an energy recovery device due to a malfunction of the PDP.

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

FIG. 2 is a plan view showing an arrangement of electrode lines and discharge cells of the PDP shown in FIG. 1; FIG.

3 is a view showing a conventional energy recovery device installed in front of the scan drive.

4 is a timing diagram and waveform diagrams illustrating on / off timings of the switches illustrated in FIG. 3 and output waveforms of panel capacitors.

5 is a circuit diagram having a logic circuit to prevent a malfunction of the switch control signal in the energy recovery device of FIG.

6 is a schematic view showing a driving device for explaining a method of driving a plasma display panel according to the present invention;

FIG. 7 is a diagram for explaining a step-by-step drive control method for protecting a system by comparing and detecting control pulses for driving an energy recovery device according to the drive device shown in FIG. 6; FIG.

8 is a detailed view of the driving circuit shown in FIG.

<Description of Symbols for Main Parts of Drawings>

10: upper substrate 11: discharge cell

12Y, 62 scan electrode 12Z, 64 sustain electrode

14 upper dielectric layer 16 protective film

18: lower substrate 20X: address electrode

22: lower dielectric layer 24: partition wall

26 phosphor 30 PDP

40: AND gate 42: Integrating circuit

44,48: comparator 46,50: holding operation control unit

In order to achieve the above object, the driving method of the plasma display panel according to the present invention comprises the steps of receiving a switch control signal for controlling the switch element; Integrating the switch control signal to output an integrated voltage of the DC voltage-controlled switch control signal; Generating a control signal by comparing an integrated voltage of the switch control signal with a predetermined reference voltage; And controlling the driving of the energy recovery device in response to the control signal. The control signal has a high logic value and a low logic value. The driving method of the plasma display panel may be configured to a high logic value of the control signal. And in response to normally driving the energy recovery device, and stopping the driving of the energy recovery device in response to a low logic value of the control signal. And driving the energy recovery device normally in response to a low logic value, and stopping the driving of the energy recovery device in response to a high logic value of the control signal. The driving device includes pixel cells at an intersection of the first and second sustain electrodes and the address electrode. Driving signals for generating discharge in the pixel cells using a display panel arranged in a matrix, a capacitive load that charges and discharges a voltage, and a plurality of switch elements that control the charge and discharge in response to a switch control signal. Generating energy recovery device; An electrode driver for supplying driving signals from the energy recovery device to the electrodes; An integrating circuit for integrating the switch control signal and outputting an integrated voltage of the DC control switch; A comparator for generating a control signal by comparing an integrated voltage of the switch control signal with a predetermined reference voltage; And a control unit for controlling the driving of the energy recovery device in response to the control signal. The driving device of the plasma display panel further includes a first resistor and a second resistor for dividing a voltage to generate the reference voltage. The integrating circuit includes a resistor connected in series with the comparator and inputted with the switch control signal, and a capacitor connected between the resistor and the base voltage source to form an RC integrator. First and second switch elements connected in parallel; A third switch element for supplying a sustain voltage to the electrode; A fourth switch element for supplying a base voltage to the electrode; And an inductor constituting an LC resonant circuit together with the capacitive load. The switch control signal is a control signal of the first and second switch elements. The driving device of the plasma display panel includes the third and fourth switches. And an AND gate for controlling the driving of the energy recovery device by performing an AND operation on the control signal of the device.

Other objects and advantages of the present invention in addition to the above object will be apparent from the description of the preferred embodiment of the present invention with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to FIGS. 6 to 8.

Also in the present invention, as described in the related art, the driving apparatus of the PDP has m × n discharge cells 1 having scan electrode lines Y1 to Ym, sustain electrode lines Z1 to Zm, and address electrode lines. The PDP 30 arranged in a matrix so as to be connected to the X1 to Xn, the scan driver 32 for driving the scan electrode lines Y1 to Ym, and the sustain electrode lines Z1 to Zm. A sustain driver 34 for driving, odd-numbered address electrode lines X1, X3, ..., Xn-3, Xn-1 and even-numbered address electrode lines X2, X4, ..., Xn-2, Xn ) Is provided with first and second address drivers 36A and 36B for divided driving. The scan driver 32 sequentially supplies scan pulses and sustain pulses to the scan electrode lines Y1 to Ym so that the discharge cells 1 are sequentially scanned in line units, and m × n discharge cells are provided. (1) Let the discharge in each last. The sustain driver 34 supplies a sustain pulse to all of the sustain electrode lines Z1 to Zm. The first and second address drivers 36A and 36B supply image data to the address electrode lines X1 through Xn in synchronization with the scan pulse. The first address driver 36A supplies image data to the odd-numbered address electrode lines X1, X3, ..., Xn-3, Xn-1, and the second address driver 36B supplies the even-numbered address electrode lines ( Image data is supplied to X2, X4, ..., Xn-2, Xn).

In the AC surface discharge PDP thus driven, a high voltage of several hundred volts or more is required for the address discharge and the sustain discharge. Accordingly, in order to minimize the driving power required for the address discharge and the sustain discharge, an energy recovery device is added to the scan driver 32, the sustain driver 34, and the address drivers 36A and 36B. The energy recovery apparatus recovers the voltage charged between the scan electrode line (Y) and the sustain electrode line (Z) and the voltage charged between the address electrode lines (X) and reuses it as a driving voltage at the next discharge.

In addition, the energy recovery device used in the present invention is as shown in Figure 3 and performs the same operation.

6 is a schematic view showing a driving device for explaining a method of driving a plasma display panel according to the present invention, which is added to an energy recovery device in the scan driver 32 and the sustain driver 34 to prevent malfunction. .

Referring to FIG. 6, the driving apparatus of the plasma display panel includes an integrating circuit 42, a comparator 44, and a holding operation controller 46.

The integrating circuit 42 serves to integrate this control signal when a control signal is input from an external control unit (not shown) to control the switches S1 and S2 constituting the energy recovery device.

The comparator 44 compares the integral voltage Ver of the switch control signal, which is DC-voltageed by the integration of the control signal, with the predetermined reference voltage Vr due to the setting of the driving unit, and thus a high or low signal. Outputs

The holding operation control unit 46 receives the HIGH or LOW signal from the comparator 44 and controls the holding pulse for driving the sustain discharge from the scanning and holding drivers 32 and 34 to the panel. Do it.

FIG. 7 is a view for explaining a step-by-step drive control method of comparing and detecting control pulses for driving an energy recovery device according to the drive device shown in FIG.

Referring to FIG. 7, in the driving control method according to the present invention, first, a control signal for driving a switch constituting an energy recovery device is generated from an external controller. (S11) The switch is a field effect transistor (FET). The control signal is a signal for controlling the first and second switches S1 and S2 of the energy recovery apparatus. The control signal generated in this way is supplied to the integrating circuit 42 in FIG.

Next, the switch control signal of the energy recovery device is integrated. (S12) The control signal input from the previous step S11 integrates the signal generated from the external control unit periodically using the integrating circuit 42.

The integrated voltage Ver of the switch control signal is detected (S13). When the input control signal is integrated by the integrating circuit 42, a constant DC voltage can be detected. In this case, the constant DC voltage is referred to as the integral voltage Ver of the switch control signal.

When the integrated voltage Ver of the switch control signal is detected, the comparison signal is detected by comparing with the reference voltage Vr. (S14) The reference voltage Vr is a voltage that is already set and the integrated voltage Ver of the switch control signal. Is lower than a certain voltage, it is the voltage that makes the driving part not to operate. As a result, the integrated voltage Ver of the switch control signal is detected and compared with the reference voltage Vr, and outputs a high or low signal.

For example, assume a case of detecting a logic control signal of 5V level for driving an energy recovery device. In this case, when the integrated voltage Ver of the switch control signal is 3V when the control signal applied to the switch is normally operated, the reference voltage Vr is adjusted to about 2.5V and is high by the comparator 44. The signal is output. However, when a malfunction occurs in which the switch control signal of the energy recovery device does not occur, the integrated voltage Ver of the switch control signal becomes lower than when it is normal (3V). When the integrated voltage Ver of the lowered switch control signal is lower than the reference voltage Vr, a low signal is output through the comparator 44.

When the high signal is output in the previous step S14, the driving pulses are normally applied to the panel through the scanning and holding drivers 32 and 34. (S15)

When the low signal is output, the sustain pulse is stopped through the scan and sustain drivers 32 and 34. In this case, the driving units 32 and 34 have components for stopping the driving unit by receiving external high and low signals.

In addition, the method of restoring the stopped driving unit by outputting a low signal causes the original driving method to be executed again. When the integrated voltage Ver of the switch control signal becomes higher than the reference voltage Vr, the output of the comparator 44 is reset. When the signal is changed and recognized as a normal state, normal operation is performed. In this case, the normal and stop operations according to the high and low signals may be interchanged and driven.

FIG. 8 is a detailed view of the driving circuit shown in FIG. 6.

Referring to FIG. 8, the driving circuit according to the present invention is added to the energy recovery apparatuses in the scan and sustain drivers 32 and 34 to maintain the normal operation and the stop operation, and the maintenance operation control unit ( A comparator 48 connected to the reference voltage Vr and an integrated voltage Ver of the switch control signal to output a comparison detection signal, and a first resistor connected to one end of an input side of the comparator 48; A capacitor which is connected to the first resistor R1, the comparator 48 and the ground voltage source GND, and which forms an integral circuit together with the first resistor R1 to integrate the switch control signal input from the external controller. (C) and second and third connected in parallel to the other end of the input side of the comparator 48 and connected in series between the sustain voltage source Vcc and the ground voltage source GND to determine the magnitude of the reference voltage Vr. Three resistors R2 and R3 are provided.

Referring to these operations, the control signal for operating the first and second switches S1 and S2 has a constant DC voltage while passing through an integration circuit composed of the first resistor R1 and the capacitor C. FIG. For example, when the control signal pulse is a 5V logic level, the periodic control signal pulse has a DC voltage of about 4V while passing through the RC integrating circuit. This DC voltage Ver is input to the comparator 48 as one input value. The other input value input to the comparator 48 is also the reference voltage Vr in which the sustain voltage source Vcc is divided by the second and third resistors R2 and R3. At this time, the reference voltage Vr is set to about 3 to 4V.

If the control signal pulse of the energy recovery device is normally input, the output of the comparator 48 becomes HIGH, which is determined to be normal operation and driven. However, if the control signal pulse is not even partially input, the integrated voltage Ver of the switch control signal is lowered and Ver <Vr. In this case, while the output of the comparator 48 becomes LOW, the output of the comparator 48 is determined as a malfunction state, and the stop operation is performed through the holding operation controller 50. In this case, the operation according to the high and low signals may be controlled to be operated interchangeably.

Such a driving circuit is allowed to be driven only within the holding period because the energy recovery device control signal is rarely used outside the holding period.

In addition, the driving circuit according to the present invention further includes an AND gate to prevent a malfunction of the third and fourth switches S3 and S4 as described in the related art. This makes it possible to prevent all malfunctions caused by driving the energy recovery device.

As described above, the driving device and driving method of the plasma display panel according to the present invention are integrated circuits and comparators to prevent malfunctions caused by using an energy recovery device for reusing energy in driving the plasma display panel. The detection circuit composed of the plurality of driving units is additionally arranged to drive the panel to be stably driven.

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.

Claims (10)

In the method of driving a plasma display panel using an energy recovery device including a plurality of switch elements, Receiving a switch control signal for controlling the switch element; Integrating the switch control signal to output an integrated voltage of the DC voltage-controlled switch control signal; Generating a control signal by comparing an integrated voltage of the switch control signal with a predetermined reference voltage; And controlling the driving of the energy recovery device in response to the control signal. delete delete The method of claim 1, The control signal, A driving method of a plasma display panel having a high logic value and a low logic value. The method of claim 4, wherein Driving the energy recovery device normally in response to a high logic value of the control signal; And stopping driving of the energy recovery device in response to a low logic value of the control signal. The method of claim 4, wherein Driving the energy recovery device normally in response to a low logic value of the control signal; And stopping driving of the energy recovery device in response to a high logic value of the control signal. A display panel in which pixel cells are arranged in a matrix at an intersection of the first and second sustain electrodes and an address electrode; An energy recovery device for generating drive signals for causing discharge in the pixel cells by using a capacitive load that charges and discharges a voltage and a plurality of switch elements that control the charge and discharge in response to a switch control signal; An electrode driver for supplying driving signals from the energy recovery device to the electrodes; An integrating circuit for integrating the switch control signal and outputting an integrated voltage of the DC control switch; A comparator for generating a control signal by comparing an integrated voltage of the switch control signal with a predetermined reference voltage; And a control unit for controlling the driving of the energy recovery device in response to the control signal. The method of claim 7, wherein And a first resistor and a second resistor for dividing the voltage to generate the reference voltage. The method of claim 7, wherein The integrating circuit is connected in series with the comparator and a resistor to which the switch control signal is input; And a capacitor connected between the resistor and the ground voltage source to form an RC integrator. The method of claim 7, wherein The energy recovery device, First and second switch elements connected in parallel to said capacitive load; A third switch element for supplying a sustain voltage to the electrode; A fourth switch element for supplying a base voltage to the electrode; An inductor constituting an LC resonant circuit together with the capacitive load; The switch control signal is a control signal of the first and second switch elements; And an AND gate for controlling the driving of the energy recovery device by performing an AND operation on the control signals of the third and fourth switch elements.