KR20060119003A - Plasma display device - Google Patents

Abstract

A plasma display device is provided to detect defects of the plasma display device in advance by immediately detecting abnormal operation of a power recovery circuit. A plasma display device includes plural electrodes formed in one direction; at least one inductor(L) having a first stage electrically connected to the electrode; a first transistor electrically connected between the electrode and a first power source(Vs) supplying a first voltage; a second transistor electrically connected between the electrode and a second power source(0V) supplying a second voltage; a first diode(D1) having an anode electrically connected to a second stage of the inductor; a third transistor electrically connected between a cathode of the first diode and a power recovery power source supplying a third voltage having a level between the first and second voltages and turned on to form a path for reducing the voltage of the electrode; and a gate voltage supply source having a fuse and an output stage electrically connected to the cathode of the first diode, and receiving a control signal through an input stage(in) and outputting the gate voltage for controlling the gate of the first or second transistor to the output stage.

Description

Plasma display device {PLASMA DISPLAY DEVICE}

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

2 and 3 are views showing a sustain discharge driving circuit according to an embodiment of the present invention.

4A and 4B are diagrams for explaining a current path in each mode when the power recovery circuit is normally operated in the sustain discharge driving circuit according to the embodiment of the present invention.

5 is a view for explaining an operation when the circuit element (D2) is burned out in the sustain discharge drive circuit according to an embodiment of the present invention.

6 is a view for explaining an operation when the circuit element (Xr) is burned out in the sustain discharge drive circuit according to an embodiment of the present invention.

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

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

In general, the driving method of the plasma display device includes a reset period, an address period, and a sustain period.

The reset period is a period for initializing the state of each cell, and the address period is a period for selecting cells to be turned on and cells not to be turned on in the panel. The sustain period is a period in which discharge for actually displaying an image is performed on a cell to be turned on by applying a sustain discharge pulse.

On the other hand, when the sustain discharge pulse is applied to the electrode in the sustain period, the reactive power required for charging and discharging the capacitive load (hereinafter, referred to as the "panel capacitor") formed by the electrodes is needed, and thus recovering such reactive power. The power recovery circuit is used for reuse. As a power recovery circuit, L.F. There is a sustain discharge circuit proposed by Weber (US Pat. Nos. 4,866,349 and 5,081,400). The power recovery circuit charges and discharges the panel capacitor by using the resonance of the inductor and the panel capacitor.

When the power recovery operation does not occur in such a power recovery circuit, the power consumption increases, but there is no significant effect on the screen. Therefore, it is difficult to easily check whether the power recovery operation is performed on the screen. However, in the absence of the power recovery operation, hard switching occurs when the sustain discharge pulse is applied, and thus heat generation may increase and affect other peripheral circuits.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide a plasma display device capable of removing heat generated when a power recovery circuit is not operated.

According to an aspect of the present invention, a plasma display device includes a plurality of electrodes formed in one direction, at least one inductor electrically connected to a first end of the electrode, and a first voltage supplying the first voltage to the electrodes. A first transistor electrically connected between a first transistor electrically connected between a first power supply, and a second transistor electrically connected between the electrode and a second power supply supplying a second voltage, and a first anode electrically connected to a second end of the inductor. An electrical connection between a diode and a cathode of the first diode and a power recovery power supply for supplying a third voltage between the first and second voltages to form a path for reducing the voltage of the electrode at turn-on; And a third transistor and a fuse, and receives a control signal through an input terminal to open a gate of the first or second transistor. And output a gate voltage to the output terminal, the output terminal including a gate voltage source electrically connected to the cathode of the first diode.

According to another aspect of the present invention, a plasma display device is configured to supply a first transistor, an electrode, and a second voltage, which are electrically connected between a plurality of electrodes formed in one direction and a first power supply supplying the electrode and a first voltage. A first stage to a power recovery power supply for supplying a second transistor electrically connected between a second power supply and a first diode electrically connected to the electrode and a third voltage between the first voltage and the second voltage; A third transistor and a fuse electrically connected between the at least one inductor and the second end of the inductor and the cathode of the first diode, the third transistor forming a path for reducing the voltage of the electrode when turned on. And a gate voltage for controlling a gate of the first or second transistor by receiving a control signal through an input terminal. Stage outputs and is characterized in that the output stage comprises a gate voltage supply source electrically connected to the cathode of the first diode.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention. Like parts are designated by like reference numerals throughout the specification.

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

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

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

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

The plasma display panel 100 includes a plurality of address electrodes (hereinafter referred to as "A electrodes") A1 to Am extending in the column direction, and a plurality of sustain electrodes extending in pairs to each other in the row direction (hereinafter, "X electrode" (X1 to Xn) and scan electrode (hereinafter referred to as "Y electrode") (Y1 to Yn). The X electrodes X1 to Xn are formed corresponding to the respective Y electrodes Y1 to Yn, and generally have one end connected in common to each other. The plasma display panel 100 includes a substrate (not shown) on which the X and Y electrodes X1 to Xn and Y1 to Yn are arranged, and a substrate (not shown) on which the A electrodes A1 to Am are arranged. The two substrates are disposed to face each other with discharge spaces interposed so that the Y electrodes Y1 to Yn and the A electrodes A1 to Am and the X electrodes X1 to Xn and the A electrodes A1 to Am are orthogonal to each other. At this time, the discharge space at the intersection of the A electrodes A1 to Am and the X and Y electrodes X1 to Xn and Y1 to Yn forms a discharge cell.

The controller 200 receives an image signal from the outside and outputs an address driving control signal, an X electrode driving control signal, and a Y electrode driving control signal. The controller 200 divides and drives one frame into a plurality of subfields, and each subfield is composed of a reset period, an address period, and a sustain period.

The address driver 300 receives an address drive control signal from the controller 200 and applies a display data signal for selecting a discharge cell to be displayed to each address electrode.

The sustain electrode driver 400 receives the sustain electrode driving control signal from the controller 200 and applies a driving voltage to the sustain electrode.

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

FIG. 2 is a diagram illustrating a sustain discharge driving circuit according to an exemplary embodiment of the present invention, in which the switch used in FIG. 2 is illustrated as an n-channel field effect transistor having a body diode (not shown). It can be made with other switches. In addition, although each transistor may be formed of a plurality of transistors connected in parallel, the transistors are illustrated and described as one transistor in FIG. 2. In FIG. 2, the capacitive components formed by the X and Y electrodes are illustrated as panel capacitors Cp for convenience.

As shown in FIG. 2, the sustain discharge driving circuit according to the embodiment of the present invention includes a power recovery unit 410, a sustain voltage supply unit 420, a gate voltage supply unit 430, and a diode D3.

The sustain voltage supply unit 420 includes two transistors Xa and Xg. Transistor Xa is connected between the power supply supplying the sustain discharge voltage Vs and the X electrode of the panel capacitor Cp, and the transistor Xg is the power supply supplying the ground voltage and the X electrode of the panel capacitor Cp. It is connected between. The transistors Xa and Xg respectively supply a Vs voltage and a ground voltage to the X electrode of the panel capacitor Cp.

The power recovery unit 410 includes transistors Xr and Xf, an inductor L, diodes D ₁ and D ₂ , and a power recovery capacitor C 1. The capacitor C1 is charged with a Vs / 2 voltage corresponding to an intermediate voltage between the two voltages Vs and 0V supplied from the sustain voltage supply unit 420.

The drain of the transistor Xs is connected to the power supply Vs supplying the voltage Vs, and the source of the transistor Xg is connected to the ground terminal 0. The source of the transistor Xs and the drain of the transistor Xg are connected to the X electrode of the panel capacitor Cp, and the first end of the inductor L is connected to the Y electrode of the panel capacitor Cp.

Transistor Xr has a drain connected to capacitor C1 and a source connected to the second end of the inductor L. Transistor Xg has a drain connected to the second end of the inductor L and a source connected to the capacitor ( Connected to C1). In general, since there are body diodes in the transistors Xr and Xg, the diode D1 is connected between the source of the transistor Xr and the second end of the inductor L to block the path formed by the body diode. Diode D2 is connected between the drain of transistor Xg and the second end of inductor L.

Unlike FIG. 2, the inductor L may be connected between the power recovery capacitor C1 and the transistors Xr and Xf.

In the power recovery unit 410, the connection order between the inductor L, the diode D1, and the transistor Xr may be changed. Can be changed.

The gate voltage supply unit 430 includes an amplifier and a fuse, and receives a control signal (for example, a signal having 0V and 5V) through an input terminal in to transistors Xr, Xf, Xs, and Xg. Gate voltages (for example, 0V and 15V) for driving the voltage are generated, and the generated gate voltage is applied to the gates of the transistors Xr, Xf, Xs, and Xg. In addition, the diode D3 is further connected to the output terminal of the gate voltage supply unit 430 to prevent the power recovery current from flowing back toward the gate drive power supply 5V.

In FIG. 2, only the gate voltage supply unit 430 having the output terminal connected to the gate of the transistor Xg is illustrated, but the gate voltage supply unit having the output terminal connected to the gate of the transistor Xs is also connected to the contact between the diode D2 and the transistor Xf. Can be connected.

The fuse is opened when the circuit elements D2 and Xr of the power recovery unit 410 are burned out, so that the gate voltage is not supplied from the gate voltage supply unit 430 to the transistors Xg and / or Xs. Therefore, when an abnormality occurs in the power recovery unit 410, the transistors Xg and / or Xs do not operate and hard switching does not occur.

3, the fuse may be connected between the input terminal in and the amplifier in the gate voltage supply unit 430, and the fuse may be connected to a contact point of the diode D2 and the transistor Xf. have. In this case, the diode D3 may be connected between the contact of the diode D2 and the transistor Xf and the fuse to block the current path in the opposite direction.

Next, the operation of the sustain discharge driving circuit for generating the sustain discharge pulse will be described in detail with reference to FIGS. 4A and 4B.

4A and 4B are diagrams for explaining a current path in each mode when the power recovery circuit is normally operated in the sustain discharge driving circuit according to the embodiment of the present invention.

First, before the mode 1 starts, the transistor Xg is turned on so that the voltage across the panel is maintained at 0V, and the capacitor C1 has a voltage (Vs / 2) equal to 1/2 of the externally applied voltage (Vs). Assume that it is precharged.

First, in mode 1, transistor Xr is turned on and transistor Xg is turned off. Then, as shown in FIG. 4A, a resonance path of the capacitor Cp-transistor Xr-diode D1-inductor L-panel capacitor Cp is formed (M1). Resonant current flows through the resonance path M1 to charge the panel capacitor Cp so that the X electrode voltage of the panel capacitor Cp is Vs. Increases to near voltage.

Next, in mode 2, the transistor Xs is turned off after the transistor Xs is turned on. Then, as shown in FIG. 4A, a path of the power source Vs-transistor Xs-panel capacitor Cp is formed (M2). The voltage Vs is applied to the X electrode of the panel capacitor Cp by this path M2.

Next, in mode 3, transistor Xf is turned on and transistor Xs is turned off. Then, as shown in FIG. 4B, a resonance path of the panel capacitor Cp, the inductor L, the diode D2, the transistor Xf, and the capacitor C1 is formed (M3). The resonance current flows through the resonance path M3 to discharge the voltage charged in the panel capacitor Cp so that the X electrode voltage of the panel capacitor Cp decreases to near 0V.

Next, in the mode 4, the transistor Xf is turned off after the transistor Xg is turned on. Then, as shown in FIG. 4B, a path of the panel capacitor Cp-transistor Xg-power source 0V is formed (M4). By this path, a 0V voltage is applied to the X electrode of the panel capacitor Cp.

In this manner, in the sustain period, the sustain discharge pulse is applied to the sustain electrode X through the resonance of the inductor L and the panel capacitor Cp through the paths M1-M4. In addition, power consumption of the plasma display panel may be reduced by the power recovery operation.

Now, a method of detecting an operation failure of the power recovery circuit in the sustain discharge driving circuit according to the embodiment of the present invention will be described in detail with reference to FIGS. 5 and 6.

5 and 6 are views for explaining the operation of the sustain discharge driving circuit according to an embodiment of the present invention.

In particular, FIG. 5 and FIG. 6 illustrate that the fuse is blown when the power recovery operation of the sustain discharge driving circuit is not properly performed, thereby preventing the influence on the peripheral circuit due to the power recovery operation not being performed. .

First, when the circuit element D2 in the power recovery unit 410 is burned out, the operation of the sustain discharge driving circuit according to the embodiment of the present invention will be described in detail with reference to FIG. 5.

FIG. 5 is a diagram illustrating a current path of the driving circuit shown in FIG. 2 when the circuit element of the power recovery unit is burned out.

As shown in FIG. 5, when the diode D2 is burned out in the power recovery unit 410, the resistance value across the diode D2 approaches zero. At this time, when the transistor Xg is turned on in the mode 4 of FIG. 4B, a path to the gate voltage supply part 430, the diode D3, and the ground GND is formed (M5). When the short current flows through the path M5, the fuse is opened and the gate voltage is not output from the gate voltage supply part 430. Accordingly, the operation of the sustain discharge driver circuit is stopped to prevent the phenomenon of smoke caused by the heat generation of the transistors Xs and Xg and damage to other circuit elements and even the plasma display device.

Next, when the circuit element Xr in the power recovery unit 410 is burned out, the operation of the sustain discharge driving circuit according to the embodiment of the present invention will be described in detail with reference to FIG. 6.

When the transistor Xr is burned out in the power recovery unit 410, the transistor Xr is in a short state. At this time, after the transistor Xf is turned on in the mode 4 of FIG. 4B, the path M6 as shown in FIG. 6 is formed during the period before the transistor Xg is turned off. When the short current flows along the path M6, the fuse is opened and the gate voltage is not output from the gate voltage supply part 430. As a result, the operation of the sustain discharge driver circuit is stopped and hard switching for applying the sustain discharge pulse does not occur, thereby preventing the occurrence of smoke caused by the heat generation of the transistors Xs and Xg and damage to other circuit elements and thus the plasma display device. It becomes possible.

As described above, when a problem occurs in the operation of the power recovery circuit, that is, when the transistor Xr or the diode D2 burns out as described above, the fuse is opened to stop the operation of the driving board. The fact that a problem occurred can be detected immediately.

Therefore, in such a case, the plasma display device can be normally used only by replacing parts due to damage of circuit elements of the power recovery unit or replacing the driving board including the power recovery unit, thereby reducing the maintenance cost of the plasma display device.

Here, although the operation of the power recovery circuit for applying the sustain discharge pulse to the sustain electrode X in the sustain period has been described as an example, the same applies to the operation of the power recovery circuit for applying the sustain discharge pulse to the scan electrode Y. can do.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the invention defined in the following claims are also provided. It belongs to the scope of rights.

As described above, according to the present invention, when a problem occurs in the operation of the power recovery circuit, it may be immediately detected and the defect of the plasma display device may be detected in advance.

Claims (7)

A plurality of electrodes formed in one direction; At least one inductor having a first end electrically connected to the electrode; A first transistor electrically connected between the electrode and a first power supply for supplying a first voltage; A second transistor electrically connected between the electrode and a second power supply for supplying a second voltage; A first diode having an anode electrically connected to the second end of the inductor; A third electrically connected between the cathode of the first diode and a power recovery power supply for supplying a third voltage between the first voltage and the second voltage and forming a path for reducing the voltage of the electrode when turned on transistor; And A gate voltage supply source comprising a fuse and receiving a control signal through an input terminal and outputting a gate voltage for controlling the gate of the first or second transistor to an output terminal, the output terminal being electrically connected to the cathode of the first diode; Plasma display device comprising a. The method of claim 1, A second diode having a cathode electrically connected to the second end of the inductor; And And a fourth transistor electrically connected between the anode of the second diode and the power recovery power source and forming a path for increasing the voltage of the electrode when turned on. A plurality of electrodes formed in one direction; A first transistor electrically connected between the electrode and a first power supply for supplying a first voltage; A second transistor electrically connected between the electrode and a second power supply for supplying a second voltage; A first diode in which an anode is electrically connected to the electrode; At least one inductor having a first end electrically connected to a power recovery power supply for supplying a third voltage between the first and second voltages; A third transistor electrically connected between the second end of the inductor and the cathode of the first diode, the third transistor forming a path for reducing the voltage of the electrode when turned on; And A gate voltage supply source comprising a fuse and receiving a control signal through an input terminal and outputting a gate voltage for controlling the gate of the first or second transistor to an output terminal, the output terminal being electrically connected to the cathode of the first diode; Plasma display device comprising a. The method of claim 3, A second diode having a cathode electrically connected to the electrode; And And a fourth transistor electrically connected between the anode of the second diode and the second end of the inductor, the fourth transistor forming a path for increasing the voltage of the electrode when turned on. The method according to any one of claims 1 to 4, And a third diode having an anode electrically connected to an output terminal of the gate voltage source and a cathode electrically connected to a cathode of the first diode. The method of claim 5, A first end of the fuse is electrically connected to the input end, And the gate voltage source further comprises an amplifier electrically connected between the second end of the fuse and the output end to change the control signal to the gate voltage. The method of claim 5, A second end of the fuse is electrically connected to the output end; And the gate voltage source further comprises an amplifier electrically connected between the first end of the fuse and the input end to change the control signal to the gate voltage.

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