KR100603661B1 - Driving apparatus for plasma display panel - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving device of a plasma display panel. The present invention adjusts components and arrangements of an energy recovery circuit to prevent unnecessary resonance by using free-wheeling of an inductor, and to provide a conventional energy recovery circuit. The present invention provides a driving apparatus of a plasma display panel which reduces power consumption of the driving apparatus by reducing the number of clamping diodes.

The driving device of the plasma display panel of the present invention includes an energy recovery circuit for sustain discharge when driving the plasma display panel, wherein the energy recovery circuit includes an energy supply and recovery capacitor having one end grounded ( Css), a first inductor L1 and a second inductor L2 connected in parallel between the energy supply and recovery capacitor and the panel, and between the energy supply and recovery capacitor and the first inductor and the second inductor, respectively. A first diode D1 and a second diode D2 and a first inductor for reverse current blocking positioned between the first switch S1 and the second switch S2, the first inductor and the second inductor, and the panel electrode. And a first capacitor C1 having one end connected to ground between the first diode and the first diode.

Plasma Display Panels, Energy Recovery, Clamping

Description

Driving device of plasma display panel {DRIVING APPARATUS FOR PLASMA DISPLAY PANEL}

1 is a view showing the structure of a typical plasma display panel.

2 is a diagram illustrating an energy recovery circuit of a typical plasma display panel.

3 is an operational state diagram of the energy recovery circuit shown in FIG.

Figure 4a is a diagram showing a practical application of the energy recovery circuit according to the prior art.

4b shows another practical application of the energy recovery circuit according to the prior art;

5 is a diagram illustrating an energy recovery circuit included in a driving apparatus of a plasma display panel according to an exemplary embodiment of the present invention.

6 is an operation state diagram showing the energy recovery operation of the energy recovery circuit according to an embodiment of the present invention.

FIG. 7A is a graph illustrating simulation results of resonance of an inductor during a first state (er_up) and a second state (sus_up) in which sustain pulses are generated.

FIG. 7B is a graph illustrating a result of simulating a resonance phenomenon of an inductor during a third state (er_dn) and a fourth state (sus_dn). FIG.

The present invention relates to a driving device of a plasma display panel, and more particularly, to a driving device of a plasma display panel including an energy recovery circuit capable of reducing the number of clamping diodes and suppressing heat generation of a coil.

In general, a plasma display panel is a partition wall formed between a front substrate and a rear substrate to form a unit cell, and each cell includes neon (Ne), helium (He), or a mixture of neon and helium (Ne + He) and An inert gas containing the same main discharge gas and a small amount of xenon is filled. When discharged by a high frequency voltage, the inert gas generates vacuum ultraviolet rays and emits phosphors formed between the partition walls to realize an image. Such a plasma display panel has a spotlight as a next generation display device because of its thin and light configuration.

1 illustrates a structure of a general plasma display panel.

As shown in FIG. 1, a plasma display panel includes a front substrate in which a plurality of sustain electrode pairs formed by pairing a scan electrode 102 and a sustain electrode 103 are formed on a front glass 101, which is a display surface on which an image is displayed. The rear substrate 110 having the plurality of address electrodes 113 arranged to intersect the plurality of sustain electrode pairs on the back glass 111 forming the back surface 100 and the rear surface is coupled in parallel with a predetermined distance therebetween. .

The front substrate 100 is made of a scan electrode 102 and a sustain electrode 103, that is, a transparent electrode (a) formed of a transparent ITO material and a metal material to mutually discharge and maintain light emission of the cells in one discharge cell. The scan electrode 102 and the sustain electrode 103 provided as the bus electrode b are included in pairs. The scan electrode 102 and the sustain electrode 103 are covered by one or more upper lower dielectric layers 104 that limit the discharge current and insulate the electrode pairs, and facilitate discharge conditions on the upper lower dielectric layer 104. In order to do this, a protective layer 105 on which magnesium oxide (MgO) is deposited is formed.

The rear substrate 110 is arranged in such a manner that a plurality of discharge spaces, that is, barrier ribs 112 of a stripe type (or well type) for forming discharge cells are maintained in parallel. In addition, a plurality of address electrodes 113 which perform address discharge to generate vacuum ultraviolet rays are arranged in parallel with the partition wall 112. On the upper side of the rear substrate 110, R, G, and B phosphors 114 which emit visible light for image display during address discharge are coated. A lower dielectric layer 115 is formed between the address electrode 113 and the phosphor 114 to protect the address electrode 113.

In general, a plasma display panel having such a structure is filled with a discharge gas such as Ne, as described above, between the front substrate 100 and the rear substrate 110 at about 300 to 400 Torr, and is composed of an electrode, a dielectric layer, and a discharge gas. It acts as a capacitive element that charges and discharges itself.

On the other hand, the plasma display panel has a problem in that a large amount of power is consumed due to the charging and discharging of the panel capacitor during driving. In the recent trend of enlargement, the power consumption problem is a major obstacle to the enlargement of the panel.

In order to solve the above power consumption problem, an energy recovery device has been proposed, and the energy recovery device can efficiently use the power supplied to the panel by recovering energy supplied to the electrode and supplying it to the electrode again. To perform the function. In other words, in order to reduce power consumption of the driving circuit for driving the panel, an energy recovery circuit is used instead of a general sustain circuit when driving the panel to reduce the number of switching elements and to prevent switching loss to increase the power efficiency of the circuit.

2 is a schematic diagram illustrating a concept of an energy recovery apparatus of a general plasma display panel.

Referring to FIG. 2, the energy recovery circuit of the conventional plasma display panel includes an energy supply and a recovery capacitor Css having one end grounded, first to fourth switches S1, S2, S3 and S4 connected in series and in parallel, respectively. And an inductor L and the like.

Four driving steps are required to operate the energy recovery circuit of FIG. 2, which will be described with reference to the operating state diagram of FIG. 3.

First, when the power of the entire system is turned on at the beginning of operation and a plurality of discharges continue to occur in the panel, the discharge current of the panel is charged to the energy supply and recovery capacitor Css through the inductor L.

Thereafter, the switch S1 is turned on to supply the panel with the voltage charged in the capacitor Css (State 1). This is called a first state (er_up state).

Next, turn on S3 to supply voltage Vcc to the panel. This is called a second state (sus_up state).

Next, S2 is turned on to charge the energy supplied to the panel to the energy supply and recovery capacitor Css. This is called a third state (er_down state).

Next, turn on S4 to finally set the ground level.

That is, in the first state and the third state, the energy recovery circuit operates so that energy supplied to Css in the first state is supplied to the panel electrode through L, and energy is recovered from the panel to Css in the third state. The energy recovery circuit operates while repeating the first to fourth states. FIG. 3 (b) shows the state of the voltage VL at one node of the inductor L during the operation of the energy recovery circuit. In the first state, VL = Vcc / 2 is maintained by turning on S1 and S2 in the third state. On keeps VL = Vcc / 2 again.

Hereinafter, a practical application example of the energy recovery circuit will be described with reference to FIGS. 4A to 4B.

Indeed, a clamping diode is required for VL to maintain a stable Vcc / 2 voltage value in the first and third states. For example, when the operation is continued from the first state to the second state, the voltage Vp of the panel maintains the voltage of Vcc, so that the voltage VL of the inductor resonates at a high frequency toward Vcc. At this time, a peak voltage of more than the Vcc voltage is generated to cause an electromagnetic interference (EMI) problem due to peaking, and an unnecessary resonance phenomenon is caused. In order to prevent this, a clamping diode is required.

4A shows diodes D3 and D4 further designed for clamping as a first example of a conventional energy recovery circuit. In general, clamping means fixing a portion of a repetitive waveform to a certain level, and is applied to limit a voltage change or the like to a certain range during switching. Normally, the high level of the output is fixed by using a diode.

FIG. 4B is a method of dividing the inductor into a first state er_up and a third state er_dn. In this case, twice the clamping diode is required as compared to FIG. 4A.

As described above, the energy recovery circuit according to the related art requires a large number of switching elements and clamping diodes to configure the energy recovery circuit, thereby increasing the cost and increasing the size due to the increase in the number of components. Therefore, there is a problem in that the power consumption of the panel driving circuit is consumed a lot.

The present invention to solve this problem by adjusting the components and arrangement of the energy recovery circuit to prevent unnecessary resonance by using the free-wheeling of the inductor, while reducing the number of clamping diodes compared to the conventional energy recovery circuit. It is an object of the present invention to provide a driving device of the plasma display panel which reduces the power consumption of the driving device.

In the plasma display panel driving apparatus according to the present invention for achieving the above object, the plasma display panel driving apparatus including an energy recovery circuit for sustain discharge when driving the plasma display panel, the energy recovery circuit is the one end is grounded energy A supply and recovery capacitor Css, a first inductor L1 and a second inductor L2 connected in parallel between the energy supply and recovery capacitor and the panel, an energy supply and recovery capacitor and a first inductor; A first switch S1 and a second switch S2 respectively configured between the second inductor, and a first diode D1 and a second diode for blocking reverse current positioned between the first inductor and the second inductor and the panel electrode. And a first capacitor C1 having one end connected to the ground between D2 and the first inductor and the first diode.

And a second capacitor C2 having one end connected to a ground between the second inductor and the second diode.

One end of the panel, the cathode of the first diode and the anode of the second diode are characterized in that one end is commonly connected to the other end of the third switch (S3) connected to the Vcc and the other end of the fourth switch (S4).

The first state (er_up) in which the first switch is turned on to supply energy pre-charged to the energy supply / recovery capacitor to the panel through the first inductor, and the third switch is turned on to supply the voltage Vcc to the panel. A second state (sus_up), a third state (er_dn) for recovering energy supplied to the panel by the second switch is turned on, and a fourth switch (ON) for grounding the panel by turning on the fourth switch (ON) It is characterized by operating in the state (sus_dn).

After the first state is finished, the resonance characteristic of the first inductor is adjusted through the first capacitor.

<Example>

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

5 is a view showing a driving apparatus of a plasma display panel including an energy recovery circuit according to an embodiment of the present invention.

Referring to FIG. 5, a first inductor L1 and a second inductor L2 are connected in parallel between an energy supply and recovery capacitor Css having one end grounded and a panel. This is a method of dividing the inductor of FIG. 3b into the first state er_up and the third state er_dn, respectively. When the energy recovery circuit is UP in the first state, energy is supplied to the panel electrode through L1. In the third state, when the energy recovery circuit is down, the energy of the panel electrode is recovered to the energy supply and recovery capacitor Css through L2. However, the biggest difference compared to FIG. 4B is that a plurality of clamping diodes are not additionally installed and only two clamping diodes are installed. That is, clamping diodes D1 and D2 are positioned between the first inductor L1 and the second inductor L2 and the panel electrode, and between the first inductor L1 and the first clamping diode D1 and the second inductor L2. The first capacitor C1 and the second capacitor C2 are connected to each other with one end connected to the ground between the second clamping diode D2 and the second clamping diode D2.

That is, in the conventional energy recovery circuit, a diode is disposed between the inductor and the energy recovery capacitor. However, in the present invention, a difference between the diode is disposed between the inductor and the panel electrode, and a capacitor having one side grounded between the diode and the inductor is installed. Therefore, the resonance characteristic of the inductor can be adjusted.

Hereinafter, an energy recovery operation of the energy recovery device according to an embodiment of the present invention will be described with reference to FIG. 5.

First, when the power of the entire system is turned on at the beginning of operation and a plurality of discharges continue to occur in the panel, the discharge current of the panel is charged to the energy supply and recovery capacitor Css through the second inductor L2.

Thereafter, the switch S1 is turned on to supply the voltage charged in the Css to the panel through the first inductor L1 (State 1). This is called a first state (er_up state).

In the first state, Vp and Vp 'rise while VL maintains the Vcc / 2 voltage. At this time, since the resonance phenomenon may occur unnecessarily even after the first state is terminated, the resonance characteristic of the inductor L1 is adjusted through the dummy capacitor C1 to prevent this.

Next, turn on S3 to supply voltage Vcc to the panel. This is called a second state (sus_up state).

Then, turn on S2 to charge the energy supplied to the panel to the energy supply and recovery capacitor (Css). This is called a third state (er_down state). In this case, as in the case where the first state is terminated, the resonance phenomenon may occur unnecessarily Vp ', and thus, the resonance characteristic of the inductor L2 is adjusted through the dummy capacitor C2 to prevent this.

Finally, turn on S4 to set the ground level. This is called a fourth state.

That is, in the first state and the third state, the energy recovery circuit operates so that energy supplied to Css in the first state is supplied to the panel electrode through L1, and energy is recovered from the panel to Css through L2 in the third state. . The energy recovery circuit operates while repeating the first to fourth states. During operation of the energy recovery circuit, the state of VL at one node of the inductor L maintains VL = Vcc / 2 by S1 on in the first state and VL = Vcc / 2 again by S2 On in the third state. Will be maintained.

Referring to FIG. 6, the output waveform of Vp is similar to that of the related art, but the voltage of Vp ′ performs free-wheeling operation as a dotted line in the second state of sus_up. That is, the resonance peak in the second state (sus_up) becomes the peak at the start of the third state (er_dn), so that the resonance in the second state, but the unnecessary high frequency resonance does not occur as in the conventional do. This reduces the heating loss of the inductor and does not generate a resonance waveform of more than Vcc, thus eliminating the need for a conventional clamping diode. The resonant frequency may be adjusted through the values of C1 and C2. Since the operating characteristic is a value related to the capacitance of the panel, an appropriate value may be selected according to the driving conditions of the panel.

7 is a graph showing the simulation results of the drive circuit of the present invention on a computer.

FIG. 7A is a graph illustrating a resonance phenomenon of an inductor during a first state er_up and a second state sus_up in which a sustain pulse is generated, and FIG. 7B illustrates a third state er_dn and a fourth state sus_dn. Is a graph showing the results of simulating the resonance phenomenon of an inductor.

Referring to FIG. 7A, it can be seen that the resonance phenomenon of the inductor occurs in the process of generating the sustain pulse. At this time, it can be seen that an optimum operating condition can be made by matching the resonance frequency with the sustain pulse driving timing.

Meanwhile, referring to FIG. 7B, the er_up process and the er_dn process may be operated in the same manner.

On the other hand, in order to operate the energy recovery circuit according to the present invention more stably, it is preferable to drive the On operation (er_up) of S1 together with the sus_up operation, as seen in the control condition of FIG. Similarly, it is preferable to drive the On operation (er_dn) of S2 together with the sus_dn operation. The two operations are not necessarily driven together, but if preferably driven together, the circuit configuration can be further simplified and the reliability of the operation can be increased.

The energy recovery apparatus according to the present invention may allow only one state of the er_up or er_dn operation to be implemented, and the other state may use the prior art.

That is, only one of the dummy capacitors C1 or C2 may be installed and the other may be operated by installing a clapping diode as in the prior art. However, as described above, the circuit configuration and the inductor heat may be suppressed. In order to achieve this, it is preferable to configure both operations.

As described in detail above, the present invention adjusts the components and arrangement of the energy recovery circuit to prevent unnecessary resonance by using free-wheeling of the inductor, while reducing the number of clamping diodes compared to the conventional energy recovery circuit. By reducing the power consumption of the drive device to provide a driving device of the plasma display panel.

As described above, the technical configuration of the present invention described above will be understood by those skilled in the art that the present invention can be implemented in other specific forms without changing the technical spirit or essential features of the present invention.

Therefore, the exemplary embodiments described above are to be understood as illustrative and not restrictive in all respects, and the scope of the present invention is indicated by the following claims rather than the detailed description, and the meaning and scope of the claims and All changes or modifications derived from the equivalent concept should be interpreted as being included in the scope of the present invention.

As described in detail above, the present invention can reduce the number of switching elements in the configuration of the energy recovery circuit can be reduced cost and size reduction, it is possible to prevent the addition of the clamping diode by preventing unnecessary resonance phenomenon of the conventional inductor. .

In addition, there is an effect that can prevent a problem that consumes a lot of power consumption of the panel driving circuit due to a plurality of circuit components.

Claims (5)

A plasma display panel driving apparatus comprising an energy recovery circuit for sustain discharge when driving a plasma display panel, The energy recovery circuit An energy supply and recovery capacitor Css whose one end is grounded; A first inductor L1 and a second inductor L2 connected in parallel between the energy supply and recovery capacitor and the panel; A first switch S1 and a second switch S2 respectively configured between the energy supply and recovery capacitor and a first inductor and a second inductor; A clamping first diode D1 and a second diode D2 positioned between the first inductor and the second inductor and the panel electrode; And a first capacitor (C1) having one end connected to a ground between the first inductor and the first diode. The method of claim 1, And a second capacitor (C2) having one end connected to a ground between the second inductor and the second diode. The method of claim 2, One end of the panel, the cathode of the first diode and the anode of the second diode are connected in common to the other end of the third switch (S3) and one end of the grounded fourth switch (S4) connected to one Vcc Drive of display panel. The method of claim 3, wherein A first state (er_up) in which the first switch is turned on so that energy pre-charged in the energy supply and recovery capacitor is supplied to the panel through the first inductor; A second state sus_up for supplying the voltage Vcc to the panel by turning on the third switch, A third state er_dn in which the second switch is turned on to recover energy supplied to the panel to the energy supply and recovery capacitor; And the fourth switch is turned on to operate in a fourth state (sus_dn) for grounding the panel. The method of claim 4, wherein And the resonance characteristic of the first inductor is adjusted through the first capacitor after the first state is terminated.

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