KR20090054222A - Plasma display and driving method thereof - Google Patents

Abstract

In the plasma display device, a power recovery switch is connected between the power recovery capacitor and the address electrode to the address electrode driver for driving the address electrode, and a driving switch is connected between the power supply supplying the Va voltage and the address electrode. . A grounding switch is connected between the ground terminal and the address electrode. The address electrode driver turns on the power recovery switch to change the voltage of the address electrode from the 0V voltage to the Va / 2 voltage, and then applies the Va voltage to the address electrode by repeatedly turning the driving switch a predetermined number of times.

PDP, Electrode, Power Recovery, Switch, Integrated Circuit, TCP, Discharge

Description

Plasma display device and driving method thereof {PLASMA DISPLAY AND DRIVING METHOD THEREOF}

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

The plasma display device is a display device using a plasma display panel that displays text or an image by using plasma generated by gas discharge.

In the plasma display device, one frame is divided into a plurality of subfields, and the gray scale is displayed by a combination of weights of subfields in which a display operation occurs among the plurality of subfields. The light emitting cell and the non-light emitting cell are selected by the address discharge during the address period of each subfield, and the image is actually displayed by the sustain discharge performed on the light emitting cell during the sustain period.

In order to select the light emitting cell and the non-light emitting cell in the address period of each subfield, scan pulses are sequentially applied to the plurality of scan electrodes, and address pulses are selectively applied to the plurality of address electrodes. At this time, since the scan electrode and the address electrode act as capacitive components, a capacitance component exists in the panel. Therefore, in order to apply the address pulse to the address electrode, reactive power for generating a predetermined voltage to the panel capacitor is required in addition to the power for the address discharge. Accordingly, the panel capacitor is charged or discharged by using the power recovery capacitor to recover and reuse reactive power generated when the address pulse is applied to the address electrode.

However, after the panel capacitor is charged using the power recovery capacitor, when a switch connected to a power supply for supplying a voltage (for example, Va) of an address pulse is turned on, a sudden current flows to the panel capacitor. The sudden current change of the panel capacitor generates noise, and due to the generation of noise, it is impossible to output normal address pulses, that is, normal address data.

In addition, an integrated circuit for transmitting address data to a plurality of address electrodes is formed in the plasma display device. In an integrated circuit, when a plurality of output terminals are connected one-to-one to a plurality of address electrodes, and fewer than the number of address electrodes of the number of output terminals, a plurality of integrated circuits are used in the plasma display device. At this time, a sudden current change of the panel capacitor generates heat in the integrated circuit, and as the number of output terminals increases, more heat is generated and eventually the integrated circuit is burned out. In other words, the rapid current change of the panel capacitor makes it difficult to multi-channel the integrated circuit.

SUMMARY OF THE INVENTION An object of the present invention is to provide a plasma display device and a driving method thereof capable of reducing noise generated due to a sudden current change.

According to an embodiment of the present invention, an electrode, a power recovery capacitor, a first switch, a second switch, a third switch, and a controller are included. The first switch controls the current path between the power recovery capacitor and the electrode. The second switch is connected between the first power supply for supplying a first voltage and the electrode. The third switch is connected between the electrode and a second power supply for supplying a second voltage lower than the first voltage. The controller turns on the first switch during the first period of the period of changing the voltage of the electrode from the second voltage to the first voltage, and then turns on / off the second switch for the remaining second period.

According to another embodiment of the present invention, a method of driving a plasma display device including an electrode is provided. The driving method may include changing a voltage of the electrode by turning on a first switch controlling a current path between the electrode and the power recovery capacitor, and being connected between the first power supply supplying the first voltage and the electrode. Changing the voltage of the electrode by repeatedly turning on / off the second switch, and applying the first voltage to the electrode.

According to an embodiment of the present invention, after the voltage of the address electrode is changed by using the voltage charged in the power recovery capacitor, the voltage of the address electrode is changed by repeating turn-on / turn-off of the driving switch, thereby rapidly changing the current. Noise can be minimized. This also minimizes address data loss and enables multichannelization of integrated circuits.

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.

Throughout the specification, when a part is said to "include" a certain component, it means that it can further include other components, except to exclude other components unless specifically stated otherwise.

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. When a part is connected to another part, this includes not only a directly connected part but also a case where another part is connected in between.

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

1 is a diagram schematically 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 electrode driver 300, a sustain electrode driver 400, and a scan electrode driver 500. It includes.

The plasma display panel 100 includes a plurality of address electrodes (hereinafter referred to as "A electrodes") A1-Am extending in the column direction, and a plurality of sustain electrodes extending in pairs with each other in the row direction (hereinafter, " X electrodes "(X1-Xn) and scan electrodes (hereinafter referred to as" Y electrodes ") (Y1-Yn). In general, the X electrodes X1 to Xn are formed corresponding to the respective Y electrodes Y1 to Yn, and the display for displaying an image in the sustain period between the X electrodes X1 to Xn and the Y electrodes Y1 to Yn. Perform the action. The Y electrodes Y1-Yn and the X electrodes X1-Xn are arranged to be orthogonal to the A electrodes A1-Am. At this time, the discharge space at the intersection of the A electrodes A1-Am and the X and Y electrodes X1-Xn and Y1-Yn forms a discharge cell 110 (hereinafter referred to as a cell). The structure of the plasma display panel 100 is an example, and a panel having another structure to which the driving waveform described below may be applied may also be applied to the present invention.

The controller 200 receives an image signal from the outside and outputs driving control signals of the A electrodes A1-Am, the X electrodes X1-Xn, and the Y electrodes Y1-Yn, and outputs one frame for each luminance weight. Driving is performed by dividing into a plurality of subfields having.

The address electrode driver 300 applies a driving voltage to the A electrodes A1-Am according to the driving control signal from the controller 200. In particular, the address electrode driver 300 selectively applies an address pulse for selecting the light emitting cells and the non-light emitting cells to the A electrodes A1-Am during the address period.

The sustain electrode driver 400 applies a driving voltage to the X electrodes X1-Xn according to the drive control signal from the controller 200.

The scan electrode driver 500 applies a driving voltage to the Y electrodes Y1-Yn according to the driving control signal from the controller 200. In particular, the scan electrode driver 500 selectively applies a scan pulse to the Y electrodes Y1-Yn during the address period. For example, the scan electrode driver 400 may sequentially apply scan pulses to the Y electrodes Y1-Yn in the order in which the Y electrodes Y1-Yn are arranged in the column direction.

Next, an address electrode driver 300 according to an exemplary embodiment of the present invention will be described in detail with reference to FIG. 2.

2 is a diagram schematically illustrating an address electrode driver 300 according to an exemplary embodiment of the present invention.

As shown in FIG. 2, the address electrode driver 300 according to an exemplary embodiment of the present invention includes a plurality of addresses connected to at least one power recovery capacitor C1 and an A electrode (A1-Am of FIG. 1), respectively. The drive circuit 310 is included. The address driving circuit 320 includes a driving switch S1, a grounding switch S2, and a power recovery switch S3.

In FIG. 2, only the address driving circuit 310 connected to one A electrode is illustrated for convenience of description, and a capacitive component formed by the A electrode and the Y electrode is illustrated as a panel capacitor Cp. The predetermined number of address driving circuits 310 among the plurality of address driving circuits 310 may be manufactured in the form of one integrated circuit (IC). The integrated circuit may be mounted in the form of a chip in a packaging connection member such as a tape carrier package (TCP). The packaging connection member is adhered to a printed circuit board (not shown) of the plasma display panel 100 and the address electrode driver 300, and the power recovery capacitor C1 is mounted on the printed circuit board so that the packaging connection member is integrated circuit. Can be connected to. In addition, at least one power recovery capacitor C1 may be commonly connected to the plurality of address driving circuits 310 connected to the A electrode (A1-Am in FIG. 1), and the predetermined number of address driving circuits (for example, For example, a separate power recovery capacitor C1 may be connected to each integrated circuit formed of a predetermined number of address driving circuits. At this time, the size of the power recovery capacitor (C1) compared to the panel capacitor (Cp) is large, the power recovery capacitor (C1) by the current charged or discharged in the panel capacitor (Cp) when the power recovery switch (S3) is turned on Assume that the change in voltage is small. The power recovery capacitor C1 is charged with a voltage between Va and 0V (for example, approximately Va / 2).

Subsequently, a second end of the driving switch S1 having the first end connected to the high level voltage of the address pulse, that is, the power supply Va supplying the address voltage Va, is connected to the A electrode. A second end of the grounding switch S2 is connected to the A electrode, the first end of which is connected to a power supply for supplying a low level voltage, i.e., a beer dress voltage (0V in FIG. 2). The second end of the power recovery switch S3 having the first end connected to the power recovery capacitor C1 is connected to the A electrode. In FIG. 2, a field effect transistor may be used for each of the switches S1, S2, and S3, and another switch having the same or similar function may be used. In addition, when the transistor in which the body diode is formed is used as the switches S1, S2, and S3, the power recovery switch S3 is used to block a path in which the power recovery capacitor C1 is charged or discharged due to the body diode. It may also be formed of a transistor connected in a back-to-back form.

Next, the operation of the switches S1, S2, and S3 according to the control signal of the controller 200 will be described in detail with reference to FIGS. 3, 4A, and 4D.

3 is a diagram illustrating signal timings of the switches S1, S2, and S3 illustrated in FIG. 2, and FIGS. 4A to 4D are diagrams illustrating current paths according to the signal timing illustrated in FIG. 3, respectively. First, it is assumed that the grounding switch S2 is turned on and the ground voltage 0V is applied to the A electrode A before the mode 1 M1 starts.

3 and 4A, in mode 1 M1, the controller 200 turns off the grounding switch S2 and turns on the power recovery switch S3. Then, the voltage charged in the power recovery capacitor C1 is directly charged to the panel capacitor Cp through the current path of the power recovery capacitor C1, the power recovery switch S3, and the panel capacitor Cp. . Then, the voltage of the A electrode increases from 0V to near the predetermined voltage. At this time, the voltage of the A electrode is determined by the turn-on time of the power recovery switch S3. As described above, assuming that a voltage Va / 2 is charged in the power recovery capacitor C1 and that the capacity of the power recovery capacitor C1 is large, the voltage of the A electrode A increases to approximately Va / 2 voltage. can do.

When the voltage of the power recovery capacitor C1 is directly charged to the panel capacitor Cp, the charging time may be shortened than when the panel capacitor Cp is charged by using the resonance of the external inductor and the panel capacitor Cp. .

3 and 4B, in mode 2 (M2), the controller 200 turns off the power recovery switch S3 and repeats the turn-on / turn-off of the driving switch S1 for the period M21. After that, the driving switch S1 is turned on for the period M22.

When the driving switch S1 is turned on, as shown in FIG. 4B, current flows to the A electrode through a path of the power supply Va, the driving switch S1, and the panel capacitor Cp, and thus the voltage of the A electrode is increased. Is increased. At this time, the voltage of the A electrode is increased in proportion to the time when the driving switch S1 is turned on. Subsequently, when the driving switch S1 is turned off, the A electrode is in a floating state. As described above, if the turn-on / turn-off of the switch S1 is repeated during the period M21, the voltage of the A electrode may increase in a step shape according to the turn-on / turn-off of the switch S1.

When the turn-on / turn-off of the driving switch S1 is repeated in the period M21, when the driving switch S1 is continuously turned on for the period M21 when the driving switch S1 is turned on. Since it becomes shorter than, it is possible to reduce the abrupt current change. Therefore, noise generation can be reduced, and thus address data loss can be minimized.

3 and 4D, in mode 3 (M3), the controller 200 turns off the driving switch S2 and turns on the power recovery switch S3. Then, as shown in FIG. 4D, the voltage charged in the panel capacitor Cp through the path of the panel capacitor Cp, the power recovery switch S3, and the power recovery capacitor Cp is the power recovery capacitor. Recovered to (C1). Then, the voltage of the A electrode A decreases from the voltage Vs to around the predetermined voltage. As described above, assuming that the capacity of the power recovery capacitor C1 is large, the voltage of the A electrode A may decrease to approximately Va / 2 voltage.

3 and 4D, in mode 4 M4, the controller 200 turns off the power recovery switch S3 and turns on the grounding switch S2. Then, as shown in FIG. 4D, a 0V voltage is applied to the A electrode of the panel capacitor Cp through the path of the panel capacitor Cp, the grounding switch S2, and the panel capacitor Cp.

The controller 200 may also plot the A electrode for a predetermined period between the mode 1 (M1) and the mode 2 (M2) and between the mode 3 (M3) and the mode 4 (M4). That is, the driving switch S1 and the power recovery switch S3 may be turned on simultaneously due to the reverse recovery time of the power recovery switch S3 in the mode 2 M2 without the floating period. As a result, an abnormality may occur in the operation of the address electrode driver 300. Similarly, in the case of the mode 4 (M4), the ground recovery switch S2 and the power recovery switch S3 may be turned on simultaneously due to the reverse recovery time of the power recovery switch S3. Then, the voltage charged in the power recovery capacitor C1 is discharged through the grounding switch S2, and an abnormality may occur in the operation of the address electrode driver 300. Therefore, when the A electrode is floated for a predetermined period between Mode 1 (M1) and Mode 2 (M2) and between Mode 3 (M3) and Mode 4 (M4), the drive switch S1 and the power recovery switch S3 Can be prevented from being turned on at the same time and the case where the grounding switch S2 and the power recovery switch S3 are turned on at the same time.

Modes 1 to 4 (M1-M4) described above operate when data applied to the A electrode A (hereinafter referred to as "address data") changes. For example, a voltage of 0 V is applied to the A electrode A during a period in which a scanning pulse is applied to the first Y electrode (Y1 in FIG. 1) (a period before M1 starts), and a second Y electrode (in FIG. 1). The voltage A is applied to the A electrode A in the period M2 during which the scan pulse is applied to Y2, and the A electrode A in the period M4 during which the scan pulse is applied to the third Y electrode (Y3 in FIG. 1). If the 0V voltage is applied to), it may operate as in Modes 1 to 4 (M1-M4). However, if Va voltage is applied to the A electrode A in the periods M2 and M4 during which the scan pulse is applied to the second and third scan electrodes Y2 and Y3 of FIG. That is, Va voltage may be continuously applied to the A electrode A without the process of reducing the voltage of the A electrode A. FIG. Similarly, if a 0 V voltage is applied to both the first and second A electrodes A, 0 V continues to A electrode A without mode 1 (M1) (i.e. without increasing the voltage of A electrode A). Voltage can be applied.

Meanwhile, in the exemplary embodiment of the present invention, the driving circuit illustrated in FIG. 2 is described as being applied to the address electrode driver 300, but the driving circuit illustrated in FIG. 2 includes the sustain electrode driver 400 and the scan electrode driver 500. Applicable to

Although the 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 present invention defined in the following claims are also provided. It belongs to the scope of rights.

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

2 is a view schematically showing an address electrode driver 300 according to an embodiment of the present invention.

3 is a diagram illustrating signal timings of the switches S1, S2, and S3 illustrated in FIG. 2.

4A to 4D are diagrams illustrating current paths according to signal timings illustrated in FIG. 3, respectively.

Claims (11)

electrode, Power recovery capacitor, A first switch controlling a current path between the power recovery capacitor and the electrode; A second switch connected between the first power supply for supplying a first voltage and the electrode; A third switch connected between the electrode and a second power supply for supplying a second voltage lower than the first voltage, and A control unit which turns on / off the second switch for the second period after turning on the first switch during a period of changing the voltage of the electrode from the second voltage to the first voltage; Plasma display device comprising a. The method of claim 1, And the control unit turns on the first switch for a third period of the period of changing the voltage of the electrode from the first voltage to the second voltage, and turns on the third switch for the remaining fourth period. The method of claim 2, And the first switch, the second switch, and the third switch are manufactured in the form of one integrated circuit. The method of claim 2, Further comprising a packaging connection member for connecting the electrode and the power recovery capacitor, And the first switch, the second switch, and the third switch are mounted to the packaging connection member. The method of claim 4, wherein The packaging connecting member includes a tape carrier package. The method according to any one of claims 1 to 5, The controller turns on the second switch after the voltage of the electrode is changed from the second voltage to the first voltage, and turns on the third switch after the voltage of the electrode is changed from the first voltage to the second voltage. Plasma display device. In the method of driving a plasma display device comprising an electrode, Changing a voltage of the electrode by turning on a first switch controlling a current path between the electrode and the power recovery capacitor; Changing the voltage of the electrode by repeating turn-on / turn-off of a second switch connected between the first power supply for supplying a first voltage and the electrode, and Applying the first voltage to the electrode Driving method comprising a. The method of claim 7, wherein And the first switch and the second switch are formed in one integrated circuit. The method of claim 7, wherein The plasma display device, Further comprising a packaging connection member for connecting the electrode and the power recovery capacitor, And the first and second switches are mounted to the packaging connection member. The method according to any one of claims 7 to 9, Turning on the first switch to change the voltage of the electrode, and Applying a second voltage lower than the first voltage to the electrode; Driving method further comprising. The method of claim 10, And a voltage between the first voltage and the second voltage is charged in the power recovery capacitor.

Images