Plasma display apparatus

Abstract

The present invention relates to a plasma display apparatus including a sustain driving apparatus that supplies a sustain signal to a panel. The plasma display apparatus includes a panel in which a front substrate having formed first and second electrodes therein and a rear substrate are coalesced, a sustain driver including a first switch for applying a first voltage to any one of the first and second electrodes and a second switch for applying a second voltage, and a circuit protection unit that controls one of the first and second switches, which has a voltage higher than a predetermined voltage, at its both ends, not to turn on. According to the present invention, when a voltage at both ends of the switch included in the sustain driving apparatus in order to supply the sustain signal is higher than a reference voltage, the switch is controlled not to turn on. It is therefore possible to prevent damage due to the short of the sustain driving apparatus and, therefore, to improve the lifespan and reliability of a product.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Further objects and advantages of the invention can be more fully understood from the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a block diagram of a general panel driving apparatus included in a plasma display apparatus;

FIG. 2 is a circuit diagram of a general sustain driving apparatus included in the plasma display apparatus;

FIG. 3 is a perspective view showing an embodiment of a PDP structure according to the present invention;

FIG. 4 is a cross-sectional view showing an embodiment of the electrode arrangement of the PDP;

FIG. 5 is a timing diagram showing an embodiment of a method of time-driving the PDP with one frame being divided into a plurality of subfields;

FIG. 6 is a timing diagram showing an embodiment of driving signals for driving the PDP;

FIG. 7 is a block diagram showing an overall construction of a sustain driving apparatus according to the present invention;

FIG. 8 is a circuit diagram showing an embodiment of the construction of the sustain driving apparatus;

FIG. 9 is a circuit diagram showing an embodiment of the construction of a circuit protection unit shown in FIG. 7;

FIG. 10 is a graph showing an embodiment of the operation of the circuit protection unit shown in FIG. 7; and

FIG. 11 is a circuit diagram showing an embodiment of the construction of a comparator included in the circuit protection unit shown in FIG. 8.

Claims

1. A plasma display apparatus, comprising: a panel in which a front substrate having formed first and second electrodes therein and a rear substrate are coalesced;a sustain driver including a first switch for applying a first voltage to any one of the first and second electrodes and a second switch for applying a second voltage; anda circuit protection unit that controls one of the first and second switches, which has a voltage higher than a predetermined voltage, at its both ends, not to turn on.

2. The plasma display apparatus of claim 1, wherein the panel comprises: a front substrate;the first and second electrode formed on the front substrate;a rear substrate;a third electrode formed on the rear substrate; andbarrier ribs formed over the rear substrate, for partitioning a plurality of discharge cells.

3. The plasma display apparatus of claim 1, wherein the predetermined voltage is ¼ or less of a sustain voltage.

4. The plasma display apparatus of claim 1, wherein the circuit protection unit controls the turn-on of the first and second switches according to an amount of a sustain signal applied to any one of the first and second electrodes.

5. The plasma display apparatus of claim 4, wherein the circuit protection unit controls the first switch not to turn on when the amount of the sustain signal is lower than a third voltage, and controls the second switch not to turn on when the amount of the sustain signal is higher than the third voltage.

6. The plasma display apparatus of claim 5, wherein the circuit protection unit comprises an OP amp for comparing the amount of the sustain signal and the third voltage.

7. The plasma display apparatus of claim 5, wherein the third voltage is set in a range of ¼ to ¾ of a sustain voltage.

8. The plasma display apparatus of claim 1, wherein the circuit protection unit controls the first switch not to turn on when a voltage at both ends of the first switch is higher than a fourth voltage, and controls the second switch not to turn on when a voltage at both ends of the second switch is higher than a fifth voltage.

9. The plasma display apparatus of claim 1, wherein the circuit protection unit comprises an OP amp for comparing a voltage at both ends of each of the first and second switches and the predetermined voltage.

10. The plasma display apparatus of claim 1, wherein at least one of the first and second switches is a FET (Field Effect Transistor), and the circuit protection unit precludes a voltage input to a gate of the FET when a drain-source voltage of the FET is higher than the predetermined voltage.

11. A plasma display apparatus, comprising: a sustain driver including a first switch for applying a sustain signal to a plasma display panel and a first voltage to the panel, and a second switch for applying a second voltage to the panel;a control unit that generates a first control signal to control the turn on/off of the first switch and a second control signal to control the turn on/off of the second switch and outputs the first and second control signals to the sustain driver; anda circuit protection unit that controls the first switch not to turn on when an amount of the sustain signal is smaller than a third voltage and controls the second switch not to turn on when the amount of the sustain signal is greater than the third voltage.

12. The plasma display apparatus of claim 11, wherein the circuit protection unit comprises: a comparator that compares the amount of the sustain signal and the third voltage;a first inverter that inverts the comparator output signal;a first NAND gate that receives the first inverter output signal and the first control signal as inputs;a second inverter that inverts the first NAND gate output signal and outputs the inverted signal to the first switch;a second NAND gate that receives the second comparator output signal and the second control signal as inputs; anda third inverter that inverts the second NAND gate output signal and outputs the inverted signal to the second switch.

13. The plasma display apparatus of claim 12, wherein the comparator comprises: a fourth inverter that inverts the sustain signal; anda fifth inverter that inverts the fourth inverter output signal,wherein the fourth and fifth inverters have a predetermined threshold voltage.

14. The plasma display apparatus of claim 12, wherein the comparator comprises: a third NAND gate using the sustain signal as two inputs; anda fourth NAND gate using the third NAND gate output signal as two inputs,wherein the third and four NAND gates have a predetermined threshold voltage.

15. The plasma display apparatus of claim 13, wherein the comparator further comprises a scale adjustment unit that scales down the sustain signal and outputs the resulting signal to the fourth inverter.

16. The plasma display apparatus of claim 15, wherein the scale adjustment unit comprises: a plurality of resistors for scaling down the sustain signal; anda diode connected between both ends of at least one of the plurality of resistors.

17. The plasma display apparatus of claim 13, wherein the comparator further comprises a resistor connected between both ends of the fourth inverter.

18. The plasma display apparatus of claim 13, wherein the comparator further comprises a resistor connected between the fourth inverter and the fifth inverter.

19. The plasma display apparatus of claim 11, further comprising an energy recovery unit that recovers and stores energy supplied to the panel, wherein the energy recovery unit comprises:a source capacitor;third and fourth switches that respectively control energy supply and recovery between the source capacitor and the panel; andan inductor that forms a resonant circuit together with the source capacitor and a capacitor of the panel.

20. The plasma display apparatus of claim 19, wherein the sustain driver further comprises a sustain voltage source that supplies a sustain voltage, and the first switch is turned on after energy is supplied to the panel by the energy recovery unit, so that the first voltage is applied to the panel, and the second switch is turned on after energy is recovered from the panel by the energy recovery unit, so that the second voltage is applied to the panel.