KR20060067007A - Driving apparatus and method for plasma display panel - Google Patents

Abstract

The present invention relates to a plasma display panel, and more particularly, to a plasma display panel driving apparatus and a driving method which can improve contrast by improving a structure of a sustain driving apparatus to reduce reactive power consumption and minimize black light. It is to.

The sustain drive device of the present invention for achieving this object is a frame memory unit for storing an image signal input from the outside, an APL unit for calculating the APL value using the image signal input from the frame memory unit, and the APL value A video signal processing unit for processing the video signal according to the present invention, a synchronous signal detector for determining the presence or absence of horizontal and vertical synchronous signals of the image, first and second comparison units for comparing the detection result values of the APL value and the synchronous signal detector; A sustain frequency controller for controlling the frequency of the sustain drive waveform according to the comparison result value of the first comparator, and a sustain pulse number controller and a sustain frequency controller and sustain for controlling the number of pulses of the sustain drive waveform according to the comparison result value of the second comparator The timing of applying the sustain drive waveform and the pulse of the sustain drive waveform are removed according to the result value of the pulse number controller. Which it is characterized in that it comprises a timing and the sustain pulse controller.

In addition, the sustain driving method of the plasma display panel according to the present invention comprises the steps of: storing the image signal input from the outside, calculating the APL value using the image signal, processing the image signal according to the APL value; And a step of detecting a synchronous signal to determine whether there is a horizontal or vertical synchronous signal of the video signal, a step of comparing the APL value with a horizontal and vertical synchronous signal detection result value, and controlling the frequency of the sustain driving waveform according to the comparison result value. According to the sustain frequency control step, the sustain pulse number control step of controlling the number of pulses of the sustain drive waveform according to the comparison result value, and the timing and sustain of applying the sustain drive waveform according to the result values of the sustain frequency control step and the sustain pulse number control step. And sustain timing and pulse control steps for controlling pulses of the drive waveform. It shall be.

Description

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

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

2 is a diagram illustrating a method of expressing image gradation of a conventional plasma display panel.

3 is a view showing a driving waveform of a conventional plasma display panel.

4 is a graph showing the relationship between the number of sustain pulses according to the APL value in the sustain driving waveform of the conventional plasma display panel.

5 is a diagram illustrating a sustain driving waveform of a plasma display panel according to a conventional APL value.

FIG. 6 is a diagram showing a sustain driving waveform of a plasma display panel applied when the APL value is 0% in the present invention compared with the conventional case.

7 is a block diagram of a sustain drive device of a plasma display panel in which the frequency of the sustain drive waveform is adjusted in the sustain drive device and method of the present invention;

Fig. 8 is a block diagram of a sustain driving apparatus of a plasma display panel in which the number of pulses of the sustain driving waveform is adjusted in the sustain driving apparatus and method of the present invention.

9 is a block diagram of a sustain drive device of a plasma display panel in which the frequency and the number of pulses of the sustain drive waveform are adjusted in the sustain drive device and method of the present invention.

10 is a diagram showing a relationship between APL and a frequency of a sustain driving waveform according to the present invention;

11 is a view showing a relationship between the APL and the number of pulses of a sustain driving waveform according to the present invention;

***** Explanation of symbols for the main parts of the drawing *****

91: frame memory section

92: APL section

93: video signal processing unit

94: synchronization signal detector

95: first comparison unit

96: second comparison unit

97: sustain frequency control unit

98: sustain pulse number control unit

99: sustain frequency and pulse control unit

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel, and more particularly, to an apparatus and method for driving a plasma display panel which improves contrast by reducing the structure of a sustain driving device and reduces power consumption.

In general, a plasma display panel forms a unit cell with a space between partition walls formed between the front substrate and the rear substrate, and each cell includes neon (Ne), helium (He), or a mixture of neon and helium (Ne +). A main discharge gas such as He) and an inert gas containing a small amount of xenon are 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, the plasma display panel is coupled in parallel with the front substrate 100, which is the display surface on which the image is displayed, and the rear substrate 110 forming the rear surface with a predetermined distance therebetween.

The front substrate 100 is a scan electrode 101 (Y electrode) and a sustain electrode 102 (Z electrode), that is, a transparent electrode formed of a transparent ITO material for mutual discharge in one discharge cell and maintaining light emission of the cell. And the Y electrode 101 and the Z electrode 102 provided as a bus electrode b made of a metal material are formed in pairs. The Y electrode 101 and the Z electrode 102 are covered by one or more dielectric layers 103 which limit the discharge current and insulate the electrode pairs, and the magnesium oxide top surface of the dielectric layer 103 to facilitate the discharge conditions. A protective layer 104 on which (MgO) is deposited is formed.

The rear substrate 110 is arranged such that a plurality of discharge spaces, that is, barrier ribs 111 of a stripe type (or well type) for forming discharge cells are maintained in parallel. In addition, a plurality of address electrodes 112 (X electrodes) that perform address discharge to generate vacuum ultraviolet rays are disposed in parallel with the partition wall 111. On the upper side of the rear substrate 110, R, G, and B phosphors 113 which emit visible light for image display during address discharge are coated. A white dielectric 114 is formed between the address electrode 112 and the phosphor 113 to protect the address electrode 112 and reflect visible light emitted from the phosphor 113 to the front substrate 100.

A method of implementing image gradation in such a plasma display panel is shown in FIG. 2.

2 is a diagram illustrating a method of implementing image grayscale of a conventional plasma display panel. As shown in the drawing, a gray level display method of a conventional plasma display panel divides one frame into several subfields having different number of emission times, and each subfield is again configured to reset a reset period (RPD) and discharge to initialize all cells. It is divided into an address period APD for selecting a cell to be used and a sustain period SPD for implementing gray scale according to the number of discharges. For example, when displaying an image with 256 gray levels, a frame period (16.67 ms) corresponding to 1/60 second is divided into eight subfields SF1 through SF8, and eight subfields SF1 through. SF8) Each is subdivided into a reset period, an address period and a sustain period.

The reset period and the address period of each subfield are the same for each subfield. The address discharge for selecting the cell to be discharged is caused by the voltage difference between the X electrode and the transparent electrode which is the Y electrode. Here, the Y electrode means a scan electrode. The sustain period is increased at a rate of 2 ⁿ ( ^where n = 0, 1, 2, 3, 4, 5, 6, 7) in each subfield. In this way, since the sustain period is different in each subfield, the gray scale of the image is expressed by adjusting the sustain period of each subfield, that is, the number of sustain discharges. The driving waveforms according to the driving method of the plasma display panel are shown in FIG. 3.

3 is a view illustrating a driving waveform according to a driving method of a conventional plasma display panel. As shown, the plasma display panel includes a reset period for initializing all cells, an address period for selecting a cell to be discharged, a sustain period for maintaining the discharge of the selected cell, and an erase for erasing wall charges in the discharged cell. Drive is divided into sections.

In the reset period, a rising ramp waveform Ramp-up is simultaneously applied to all the Y electrodes in the setup period. This rising ramp waveform causes weak dark discharge within the full discharge cells. By this setup discharge, positive wall charges are accumulated on the X and Z electrodes, and negative wall charges are accumulated on the Y electrode. Here, the Z electrode means a sustain electrode.

In the set-down period, after the rising ramp waveform is supplied, the ramp ramp starts to fall from the positive voltage lower than the peak voltage of the rising ramp waveform and falls to a specific voltage level below the ground (GND) level voltage. By causing a weak erase discharge in the cells, the wall charges excessively formed in the Y electrode are sufficiently erased. By this set-down discharge, wall charges such that the address discharge can stably occur remain uniformly in the cells.

In the address period, the negative scan signal Scan is sequentially applied to the Y electrodes, and the positive data signal is applied to the X electrode in synchronization with the scan signal. As the voltage difference between the scan signal and the data signal and the wall voltage generated in the reset period are added, an address discharge is generated in the discharge cell to which the data signal is applied. In the cells selected by the address discharge, wall charges are formed such that a discharge can occur when the sustain voltage Vs is applied. The positive electrode voltage Vz is supplied to the Z electrode so as to reduce the voltage difference between the Y electrode during the set-down period and the address period so that an erroneous discharge with the Y electrode does not occur.

In the sustain period, a sustain signal Su is alternately applied to the Y electrode and the Z electrodes. In the cell selected by the address discharge, as the wall voltage and the sustain signal in the cell are added, a sustain discharge, that is, a display discharge, occurs between the Y electrode and the Z electrode every time the sustain signal is applied.

After the sustain discharge is completed, a voltage of an erase ramp waveform (Ramp-ers) having a small pulse width and a low voltage level is supplied to the Z electrode to erase the wall charge remaining in the cells of the full screen.

4 is a graph showing a relationship between the number of sustain pulses according to an APL value used in a conventional method of driving a plasma display panel. As shown in FIG. 4, the number of sustain pulses applied to the sustain period is differently assigned according to the average picture level (APL) when the plasma display panel is driven.

A typical plasma display panel displays image information by emitting light of cells by a sustain pulse alternately applied to a scan electrode and a sustain electrode. At this time, the applied sustain pulse is a high voltage of the voltage of 180V to 220V, the power consumption is large.

In order to reduce the power consumption, in the conventional plasma display panel driving method, the maximum number of sustain pulses is allocated to the sustain period at 20% APL or less, and the number of sustain pulses allocated to the sustain period at 20% APL or more is gradually reduced.

Accordingly, the power consumption of the plasma display panel gradually increases before 20% APL, but the power consumption of the plasma display panel remains constant after 20% APL.

When the number of sustain pulses decreases with increasing APL value, not only power consumption is reduced but also the contrast increases as the number of sustain pulses allocated decreases as the number of turned-on cells decreases.

However, in the conventional plasma display panel driving method, as shown in FIG. 4, the maximum number of sustain pulses is allocated even at 0% APL. That is, even if none of the cells are addressed, a maximum number of sustain pulses are alternately applied to the scan electrode and the sustain electrode.

As such, the maximum number of sustain pulses applied at 0% APL consumes hundreds of tens of watts of high reactive power. In addition, black light is generated due to the maximum number of sustain pulses applied, which reduces contrast.

5 is a diagram illustrating a sustain driving waveform applied to a sustain electrode according to an APL value in the conventional sustain driving apparatus and method.

As shown in FIG. 5, a sustain driving pulse of the same frequency is applied to the sustain electrode regardless of the APL value. As a result, 0% APL, i.e., even when no signal is applied, the maximum number of pulses is applied, thereby increasing the reactive power consumed, and black light is generated to reduce the contrast.

The present invention has been made to solve the above problems, and to provide a driving apparatus and a driving method of the plasma display panel which can improve the contrast by reducing the reactive power consumption and minimize the black light.

In order to achieve the above object, the sustain driving apparatus adjusting the frequency of the sustain driving waveform according to the present invention includes an APL value using a frame memory unit for storing an externally input video signal and an image signal input from the frame memory unit. An APL unit for calculating, an image signal processing unit for processing a video signal according to the APL value, a synchronization signal detector for determining the presence or absence of horizontal and vertical synchronization signals of the video signal, an APL value and a detection result value of the synchronization signal detection unit A sustain frequency control section for controlling the frequency of the sustain drive waveform and a sustain timing for controlling the pulse of the sustain drive waveform in accordance with the result of the sustain frequency control section and the sustain frequency control section in accordance with the comparison result. And a pulse controller.

When there is no horizontal and vertical synchronization signal detected by the synchronization signal detector, the frequency of the sustain driving waveform is set to a minimum value.

When there are horizontal and vertical synchronization signals detected by the synchronization signal detection unit and the APL value is 1% or more and 20% or less, the frequency of the sustain drive waveform is characterized in that the maximum value.

When there is a horizontal and vertical synchronization signal detected by the synchronization signal detector and the APL value is more than 20% and less than 100%, the frequency of the sustain drive waveform decreases linearly and becomes the minimum when the APL value reaches 100%. .

The sustain driving apparatus adjusting the number of pulses of the sustain driving waveform of the present invention includes a frame memory unit for storing an externally input video signal, an APL unit for calculating an APL value using an image signal input from the frame memory unit; A video signal processor for processing a video signal according to the APL value, a sync signal detector for determining the presence or absence of horizontal and vertical sync signals of the video signal, a comparison unit for comparing the detection result values of the APL value and the sync signal detector, The sustain pulse number control unit controlling the number of pulses of the sustain drive waveform according to the comparison result value of the comparator and the sustain timing and pulse control unit controlling the timing of applying the sustain drive waveform and the pulse of the sustain drive waveform according to the result values of the sustain drive waveform. Characterized in that it comprises a.

When there is no horizontal and vertical synchronization signal detected by the synchronization signal detector, the number of pulses of the sustain driving waveform is set to a minimum value.

When there are horizontal and vertical synchronization signals detected by the synchronization signal detector and the APL value is 1% or more and 20% or less, the number of pulses of the sustain driving waveform is set to the maximum value.

If there is a horizontal and vertical synchronization signal detected by the synchronization signal detector and the APL value is greater than 20% and less than 100%, the number of pulses of the sustain drive waveform decreases linearly, and becomes the minimum value when the APL value reaches 100%. do.

The sustain drive device in which the frequency and the number of pulses of the sustain drive waveform of the present invention are adjusted includes an APL for calculating an APL value using a frame memory unit for storing an externally input video signal and an image signal input from the frame memory unit. And a video signal processor for processing the video signal according to the APL value, a synchronous signal detector for determining the presence or absence of horizontal and vertical synchronous signals of the video signal, and a first comparison result of the detection result of the APL value and the synchronous signal detector. A sustain frequency controller for controlling the frequency of the sustain drive waveform according to the comparison result of the second comparator, the first comparator, and the number of sustain pulses for controlling the number of pulses of the sustain drive waveform according to the comparison result of the second comparator Timing of applying a sustain driving waveform according to a result value of the controller, the sustain frequency controller, and the sustain pulse number controller; It characterized in that it comprises a timing and the sustain pulse control part for controlling the pulses of the drive waveform stain.

When there is no horizontal and vertical synchronization signal detected by the synchronization signal detector, the frequency and the number of pulses of the sustain driving waveform are set to minimum values.

When there are horizontal and vertical synchronization signals detected by the synchronization signal detection unit and the APL value is 1% or more and 20% or less, the frequency and the number of pulses of the sustain driving waveform are set to the maximum values.

When there are horizontal and vertical synchronization signals detected by the synchronization signal detector and the APL value is more than 20% and less than 100%, the frequency and the number of pulses of the sustain drive waveform decrease linearly and become the minimum when the APL value reaches 100%. It features.

The sustain driving method in which the frequency of the sustain driving waveform of the present invention is adjusted includes storing an externally input video signal, calculating an APL value using the video signal, and processing the video signal according to the APL value. And a synchronization signal detection step for determining the presence or absence of a horizontal and vertical synchronization signal of the video signal, comparing the APL value with the synchronization signal detection result value, and a sustain frequency for controlling the frequency of the sustain drive waveform according to the comparison result value. And a sustain timing and a pulse control step of controlling the application timing of the sustain driving waveform and the pulses of the sustain driving waveform in accordance with the result value of the control step and the sustain frequency control step.

When there is no horizontal or vertical synchronization signal detected in the synchronization signal detection step, the frequency of the sustain driving waveform is set to a minimum value.

When there are horizontal and vertical synchronization signals detected in the synchronization signal detection step and the APL value is 1% or more and 20% or less, the frequency of the sustain drive waveform is characterized in that the maximum value.

When there are horizontal and vertical synchronization signals detected in the synchronization signal detection step and the APL value is more than 20% and less than 100%, the frequency of the sustain drive waveform decreases linearly, and becomes the minimum when the APL value reaches 100%. do.

A sustain driving method in which the number of pulses of the sustain driving waveform of the present invention is adjusted includes storing an externally input video signal, calculating an APL value using the video signal, and converting the video signal according to the APL value. Processing the signal, synchronizing signal detecting step of determining the presence or absence of the horizontal and vertical synchronizing signal of the video signal, comparing the APL value and the synchronizing signal detection result value, and controlling the number of pulses of the sustain drive waveform according to the comparison result value And a sustain timing and a pulse control step of controlling the application timing of the sustain driving waveform and the pulses of the sustain driving waveform according to the result values of the sustain pulse number control step and the sustain pulse number control step.

When there is no horizontal and vertical synchronization signal detected in the synchronization signal detection step, the number of pulses of the sustain driving waveform is set to a minimum value.

When there are horizontal and vertical synchronization signals detected in the synchronization signal detection step and the APL value is 1% or more and 20% or less, the number of pulses of the sustain driving waveform is set to the maximum value.

When there are horizontal and vertical synchronization signals detected in the synchronization signal detection step and the APL value is greater than 20% and less than 100%, the number of pulses of the sustain drive waveform decreases linearly and becomes the minimum when the APL value reaches 100%. It is done.

The sustain driving method in which the frequency and the number of pulses of the sustain driving waveform of the present invention are adjusted includes storing an externally input image signal, calculating an APL value using the image signal, and performing an image according to the APL value. Processing the signal, synchronizing signal detection for determining the presence or absence of a horizontal and vertical synchronizing signal of the video signal, comparing the APL value with the synchronizing signal detection result value, and adjusting the frequency of the sustain driving waveform according to the comparison result value. According to the sustain frequency control step to control, the sustain pulse number control step to control the number of pulses of the sustain drive waveform according to the comparison result value, and the timing of applying the sustain drive waveform according to the result values of the sustain frequency control step and the sustain pulse number control step. And a sustain timing and pulse control step of controlling the pulse of the sustain drive waveform. The.

When there is no horizontal and vertical synchronization signal detected in the synchronization signal detection step, the frequency and the number of pulses of the sustain driving waveform are set to minimum values.

When there are horizontal and vertical synchronization signals detected in the synchronization signal detection step and the APL value is 1% or more and 20% or less, the frequency and the number of pulses of the sustain driving waveform are set to the maximum values.

If there are horizontal and vertical sync signals detected in the sync signal detection step and the APL value is more than 20% and less than 100%, the frequency and the number of pulses of the sustain drive waveform decrease linearly and become the minimum when the APL value reaches 100%. It is characterized by.

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

FIG. 6 is a diagram illustrating a sustain driving waveform of a plasma display panel applied when the APL value is 0% in the present invention compared with the conventional case.

As shown in FIG. 6A, in the past, when the APL value is 0%, i.e., even when there is no signal, the maximum number of sustain driving pulses is applied to the sustain electrode, causing a great waste of power.

However, in the present invention, as shown in Fig. 6B, when the APL value is 0%, that is, when there is no signal, a very small number of sustain driving pulses are applied to the sustain electrode. As such, when the number of sustain driving pulses is extremely small, not only the reactive power consumed is greatly reduced but also the black light is reduced to improve the contrast.

As a method of minimizing the number of sustain driving pulses applied to the sustain electrode for a limited sustain period as described above, a method of reducing the frequency of the sustain driving pulse to a minimum or a sustain driving pulse applied to the sustain electrode using a predetermined switching element There is a way to minimize the number of. Preferably, the frequency of the sustain driving pulse is minimized, and the number of sustain driving pulses applied to the sustain electrode is minimized by using a switching element, thereby minimizing the reactive power consumed and minimizing the black light to greatly improve the contrast. .

7 is a block diagram of a sustain driving apparatus of a plasma display panel in which the frequency of the sustain driving waveform is adjusted in the sustain driving apparatus and method of the present invention.

As shown in FIG. 7, the sustain driving apparatus of the plasma display panel according to the present invention uses a frame memory unit 71 for storing an image signal input from the outside and an image signal input from the frame memory unit 71. An APL unit 72 for calculating an APL value, an image signal processor 73 for processing a video signal according to the APL value, a sync signal detector 74 for determining the presence or absence of horizontal and vertical sync signals of the input video signal, and A comparison unit 75 for comparing the APL value with the detection result value of the synchronization signal detection unit 74, a sustain frequency control unit 77 for controlling the frequency of the sustain driving waveform according to the comparison result value of the comparison unit 75, and And a sustain timing and pulse controller 79 for controlling the timing of applying the sustain drive waveform and the pulses of the sustain drive waveform in accordance with the result value of the sustain frequency controller 77.

Looking at the principle of operation of the present invention as follows.

<Frame memory part>

The frame memory unit 71 stores an image signal input from the outside and transmits the stored image signal to the APL unit 72.

 <APL part>

The APL unit 72 calculates an APL value by using an image signal input from the frame memory unit 71 and transfers the value to the image signal processor 73 and the comparator 75.

<Video signal processor>

The image signal processor 73 processes an image signal according to an APL value.

<Synchronization signal detector>

The synchronization signal detector 74 determines the presence or absence of horizontal and vertical synchronization signals and transfers the result values to the comparison unit 75. That is, the synchronizing signal detector 74 detects the input horizontal and vertical synchronizing signals to determine the presence or absence of the synchronizing signal. If there is no synchronizing signal, the output of the synchronizing signal detecting unit 74 becomes low and is input to the comparator low state.

On the other hand, if there is a horizontal and vertical synchronizing signal, the output of the synchronizing signal detector 74 becomes high and is input to the comparator high state.

<Comparative>

The comparison unit 75 receives and compares the APL value and the detection result value of the synchronization signal detector 74, and transfers the result value to the sustain frequency controller 77. That is, when there is no horizontal and vertical synchronizing signal and receives a low state from the synchronizing signal detector 74, the min value is output regardless of the APL value of the input video signal.

On the other hand, when the horizontal and vertical synchronizing signal is detected and the high state is input from the synchronizing signal detecting unit 74, a predetermined comparison result value between max and min is output according to the APL value of the input video signal. That is, when the APL value is more than 1% and less than 20%, the max value is output. When the APL value is more than 20% and less than 100%, the comparison result decreases linearly and when the APL value reaches 100%, the min value is output.

<Sustain Frequency Control Unit>

The sustain frequency controller 77 receives and processes the comparison result value of the comparator 75 and transmits a signal for controlling the frequency of the sustain driving waveform to the sustain timing and pulse controller 79. That is, when the min value is input from the comparator 75, the minimum frequency is selected and output.

On the other hand, when a predetermined value between the max value and the min value is input to the comparator 75, the frequency corresponding to the comparison result of the comparator 75 between the maximum frequency and the minimum frequency is selected and output. That is, when the max value is input from the comparator 75, the maximum frequency is selected and outputted. When the max value is input between the min value and the min value from the comparator 75, the frequency decreases linearly and then the comparison result value. When this min, the minimum frequency is output.

<Sustain Timing and Pulse Control Unit>

The sustain timing and pulse controller 79 transmits a signal for controlling the timing of applying the sustain drive waveform and the pulse of the sustain drive waveform to the sustain electrode according to the result of the sustain frequency controller 77.

By going through this process, the frequency of the sustain drive pulses applied to the sustain electrode can be adjusted, and finally the number of sustain drive pulses applied to the sustain electrode can be adjusted.

8 is a block diagram of a sustain driving apparatus of a plasma display panel in which the number of pulses of the sustain driving waveform is adjusted in the sustain driving apparatus and method of the present invention.

As shown in FIG. 8, the sustain driving apparatus of the plasma display panel according to the present invention uses a frame memory unit 81 to store an image signal input from the outside and an image signal input from the frame memory unit 81. An APL unit 82 for calculating an APL value, a video signal processor 83 for processing a video signal according to the APL value, a sync signal detector 84 for determining the presence or absence of horizontal and vertical sync signals of the input video signal, and A comparison unit 85 for comparing the APL value with the detection result value of the synchronization signal detection unit 84, and a sustain pulse number control unit for controlling the number of pulses of the sustain driving waveform according to the comparison result value of the comparison unit 85 ( 88) and a sustain timing and pulse controller 89 for controlling the timing of applying the sustain drive waveform and the pulses of the sustain drive waveform in accordance with the result value of the sustain pulse number controller 88.

Looking at the principle of operation of the present invention as follows.

<Frame memory part>

The frame memory unit 81 stores an image signal input from the outside and transfers the stored image signal to the APL unit 82.

 <APL part>

The APL unit 82 calculates an APL value by using an image signal input from the frame memory unit 81 and transfers the value to the image signal processor 83 and the comparator 85.

<Video signal processor>

The video signal processor 83 processes the video signal according to the APL value.

<Synchronization signal detector>

The synchronization signal detector 84 determines whether there is a horizontal or vertical synchronization signal, and transmits the result value to the comparison unit 85. That is, the synchronizing signal detector 84 detects the input horizontal and vertical synchronizing signals to determine the presence or absence of the synchronizing signal. If there is no synchronizing signal, the output of the synchronizing signal detecting unit 84 becomes low and is input to the comparator low state.

On the other hand, if there is a synchronization signal, the output of the synchronization signal detector 84 becomes high and is input to the comparator in a high state.

<Comparison section>

The comparison unit 85 receives and compares the APL value and the detection result value of the synchronization signal detection unit 84 and transfers the result value to the sustain pulse number control unit 88. That is, when there is no horizontal and vertical synchronization signal and receives a low state from the synchronization signal detector 84, the min value is output regardless of the APL value of the input video signal.

On the other hand, when the horizontal and vertical synchronizing signals are detected and the high state is input from the synchronizing signal detecting unit 84, a predetermined comparison result value between max and min is output according to the APL value of the input video signal. In other words, when the APL value is more than 1% and less than 20%, the max value is output. When the APL value is more than 20% and less than 100%, the comparison result decreases linearly and when the APL value reaches 100%, the min value is output.

<Sustain pulse number control part>

The sustain pulse number control unit 88 transmits a signal for controlling the number of pulses of the sustain drive waveform to the sustain timing and pulse control unit 89 according to the comparison result of the comparison unit 85. That is, when the min value is input from the comparator 85, the minimum frequency is selected and output.

On the other hand, when a predetermined value between max and min is received from the comparator 85, a frequency corresponding to the comparison result of the comparator 85 between the maximum frequency and the minimum frequency is selected and output. That is, when the max value is received from the comparator 85, the maximum number of pulses is selected and output. When the max value is input between the min value and the min value from the comparator 85, the number of pulses decreases linearly. When the result is min, output the minimum number of pulses.

<Sustain Timing and Pulse Control Unit>

The sustain timing and pulse controller 89 transmits a signal for controlling the timing of applying the sustain drive waveform and the pulse of the sustain drive waveform to the sustain electrode according to the result value of the sustain pulse number controller 88.

Through this process, the number of sustain driving pulses applied to the sustain electrode can be adjusted.

9 is a block diagram of a sustain drive device of a plasma display panel in which the frequency and number of pulses of the sustain drive waveform are adjusted in the sustain drive device and method of the present invention.

As shown in FIG. 9, the sustain driving apparatus of the plasma display panel according to the present invention uses a frame memory unit 91 for storing an image signal input from the outside and an image signal input from the frame memory unit 91. An APL unit 92 for calculating an APL value, an image signal processing unit 93 for processing an image signal according to the APL value, a synchronization signal detection unit 94 for determining the presence or absence of horizontal and vertical synchronization signals of an input video signal, and The frequency of the sustain drive waveform is determined according to the comparison result of the first and second comparators 95 and 96 and the first comparator 95 comparing the APL value with the detection result value of the synchronization signal detector 94. The sustain pulse number control unit 98 and the sustain frequency control unit 97 and the sustain pulse number that control the number of pulses of the sustain drive waveform according to the comparison result value of the sustain frequency control unit 97 and the second comparator 96 to control Texture of the control unit 98 And a sustain timing and pulse control unit 99 for controlling the timing of applying the sustain driving waveform and the pulses of the sustain driving waveform in accordance with the value of.

Looking at the principle of operation of the present invention as follows.

<Frame memory part>

The frame memory unit 91 stores an image signal input from the outside and transmits the stored image signal to the APL unit 92.

 <APL part>

The APL unit 92 calculates an APL value using an image signal input from the frame memory unit 91 and transfers the value to the image signal processor 93 and the first and second comparators 95 and 96. .

<Video signal processor>

The video signal processor 93 processes a video signal according to the APL value.

<Synchronization signal detector>

The synchronization signal detector 94 determines the presence or absence of horizontal and vertical synchronization signals and transfers the result values to the first and second comparators 95 and 96. That is, the synchronizing signal detector 94 detects the input horizontal and vertical synchronizing signals to determine the presence or absence of the synchronizing signal.

On the other hand, if there is a horizontal and vertical synchronization signal, the output of the synchronization signal detector 94 becomes high and is input to the comparator in a high state.

<First comparator>

The first comparator 95 receives and compares the APL value and the detection result value of the synchronization signal detector 94 and transfers the result value to the sustain frequency controller 97. That is, when there is no horizontal and vertical synchronization signal and receives a low state from the synchronization signal detector 94, the min value is output regardless of the APL value of the input video signal.

On the other hand, when the horizontal and vertical synchronization signals are detected and the high signal is input from the synchronization signal detector 94, a predetermined comparison result value between max and min is output according to the APL value of the input video signal. In other words, when the APL value is more than 1% and less than 20%, the max value is output. When the APL value is more than 20% and less than 100%, the comparison result decreases linearly and when the APL value reaches 100%, the min value is output.

<Second comparison part>

The second comparator 96 receives and compares the detection result values of the APL value synchronization signal detector 94 and transfers the result values to the sustain pulse number controller 98. That is, when there is no horizontal and vertical synchronization signal and receives a low state from the synchronization signal detector 94, the min value is output regardless of the APL value of the input video signal.

On the other hand, when the horizontal and vertical synchronization signals are detected and the high state is input from the synchronization signal detector 94, a predetermined comparison result value between max and min is output according to the APL value of the input video signal. That is, when the APL value is more than 1% and less than 20%, the max value is output. When the APL value is more than 20% and less than 100%, the comparison result decreases linearly and when the APL value reaches 100%, the min value is output.

<Sustain Frequency Control Unit>

The sustain frequency controller 97 transmits a signal for controlling the frequency of the sustain driving waveform to the sustain timing and pulse controller 99 according to the comparison result of the first comparator 95. That is, when the min value is input from the first comparator 95, the minimum frequency is selected and output.

On the other hand, when a predetermined value between max and min is input from the first comparator 95, a frequency corresponding to the result of the comparison of the first comparator 95 between the maximum frequency and the minimum frequency is selected and output. That is, when the max value is input from the first comparator 95, the maximum frequency is selected and output. The max frequency is linearly reduced when the max value is input from the max value to the min value. When the comparison result is min, the minimum frequency is output.

<Sustain pulse number control part>

The sustain pulse number controller 98 transmits a signal for controlling the number of pulses of the sustain driving waveform to the sustain timing and pulse controller 99 according to the comparison result value of the second comparator 96. That is, when the min value is input from the second comparator 96, the minimum frequency is selected and output.

On the other hand, when a predetermined value between max and min is received from the second comparator 96, the number of pulses corresponding to the comparison result of the second comparator 96 between the maximum frequency and the minimum frequency is selected and output. . That is, when the max value is input from the second comparator 96, the maximum number of pulses is selected and output. If the max value is input from the max value min to the min value, the pulse number is linear. It decreases by and outputs the minimum number of pulses when the comparison results in min.

<Sustain Timing and Pulse Control Unit>

The sustain timing and pulse controller 99 transmits a signal for controlling the timing of applying the sustain driving waveform and the pulse of the sustain driving waveform to the sustain electrode according to the result values of the sustain frequency controller 97 and the sustain pulse number controller 98. .

Through this process, the number of sustain driving pulses applied to the sustain electrode can be adjusted.

10 is a diagram illustrating a relationship between an APL value and a frequency of a sustain driving waveform according to the present invention.

As shown in FIG. 10, when there is no horizontal or vertical synchronization signal detected by the synchronization signal detector, that is, when there is no signal, the APL value is 0%. At this time, the reactive power consumed by minimizing the frequency of the sustain driving waveform Not only can it be greatly reduced, but the black light is reduced to improve contrast.

When there are horizontal and vertical synchronization signals detected by the synchronization signal detection unit and the APL value is 1% or more and 20% or less, the contrast is raised by setting the frequency of the sustain drive waveform to the maximum value.

If there are horizontal and vertical sync signals detected by the sync signal detector and the APL value is greater than 20% and less than 100, the frequency of the sustain drive waveform decreases linearly, and the power consumption is reduced by making the minimum value when the APL value reaches 100%. do.

11 is a diagram illustrating a relationship between an APL value and the number of pulses of a sustain driving waveform according to the present invention.

As shown in FIG. 11, when there is no horizontal or vertical synchronization signal detected by the synchronization signal detector, that is, when there is no signal, the APL value is 0%. Not only can greatly reduce, but also reduces black light to improve contrast.

When there are horizontal and vertical synchronization signals detected by the synchronization signal detector and the APL value is 1% or more and 20% or less, the contrast is increased by setting the number of pulses of the sustain drive waveform to the maximum value.

If there are horizontal and vertical sync signals detected by the sync signal detector and the APL value is greater than 20% and less than 100, the number of pulses of the sustain drive waveform decreases linearly, and when the APL value reaches 100%, the minimum power consumption is achieved. Reduce.

As described above, it will be understood by those skilled in the art that the above-described technical configuration may be implemented in other specific forms without changing the technical spirit or essential features of the present invention. Therefore, the above-described embodiments are to be understood as illustrative and not restrictive in all respects, and the scope of the present invention is indicated by the appended 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 has the effect of improving the contrast and reducing power consumption by adjusting the sustain driving pulse applied to the sustain electrode at the time of no signal by improving the structure of the sustain driving device.

Claims (24)

A frame memory unit which stores an image signal input from the outside; An APL unit which calculates an APL value using the video signal input from the frame memory unit; An image signal processor configured to process the image signal according to the APL value; A synchronization signal detector for determining the presence or absence of horizontal and vertical synchronization signals of the video signal; A comparison unit comparing the APL value and a detection result value of the synchronization signal detection unit; A sustain frequency control unit controlling a frequency of a sustain driving waveform according to a comparison result value of the comparison unit; And And a sustain timing and a pulse controller for controlling the timing of applying the sustain driving waveform and the pulses of the sustain driving waveform in accordance with the result value of the sustain frequency controller. The method of claim 1, And a frequency of the sustain drive waveform to a minimum value when there is no horizontal or vertical sync signal detected by the sync signal detector. The method of claim 1, And a horizontal and vertical synchronizing signal detected by the synchronizing signal detecting unit and setting the frequency of the sustain driving waveform to a maximum value when the APL value is 1% or more and 20% or less. The method of claim 1, When there are horizontal and vertical synchronization signals detected by the synchronization signal detection unit and the APL value is greater than 20% and less than 100%, the frequency of the sustain driving waveform decreases linearly and becomes the minimum when the APL value reaches 100%. A sustain drive device for a plasma display panel. A frame memory unit which stores an image signal input from the outside; An APL unit which calculates an APL value using the video signal input from the frame memory unit; An image signal processor configured to process the image signal according to the APL value; A synchronization signal detector for determining the presence or absence of horizontal and vertical synchronization signals of the video signal; A comparison unit comparing the APL value and a detection result value of the synchronization signal detection unit; A sustain pulse number control unit controlling the number of pulses of the sustain driving waveform according to the comparison result value of the comparison unit; And And a sustain timing and a pulse controller for controlling the timing of applying the sustain driving waveform and the pulses of the sustain driving waveform in accordance with the result value of the sustain pulse number controller. The method of claim 5, wherein And a pulse number of the sustain driving waveform is minimized when there is no horizontal and vertical synchronizing signal detected by the synchronizing signal detector. The method of claim 5, wherein And the pulse number of the sustain driving waveform is a maximum value when there are horizontal and vertical synchronization signals detected by the synchronization signal detector and the APL value is 1% or more and 20% or less. The method of claim 5, wherein When there is a horizontal and vertical synchronization signal detected by the synchronization signal detector and the APL value is greater than 20% and less than 100%, the number of pulses of the sustain driving waveform decreases linearly and becomes the minimum when the APL value reaches 100%. A sustain drive device for a plasma display panel. A frame memory unit which stores an image signal input from the outside; An APL unit which calculates an APL value using the video signal input from the frame memory unit; An image signal processor configured to process the image signal according to the APL value; A synchronization signal detector for determining the presence or absence of horizontal and vertical synchronization signals of the video signal; First and second comparison units for comparing the APL value with a detection result value of the synchronization signal detector; A sustain frequency control unit controlling a frequency of a sustain driving waveform according to a comparison result value of the first comparator; A sustain pulse number control unit controlling the number of pulses of the sustain driving waveform according to the comparison result value of the second comparator; And  And a sustain timing and pulse controller for controlling the timing of applying the sustain driving waveform and the pulses of the sustain driving waveform in accordance with the result values of the sustain frequency controller and the sustain pulse number controller. The method of claim 9, And a frequency and a number of pulses of the sustain driving waveform as minimum values when there is no horizontal and vertical synchronization signals detected by the synchronization signal detector. The method of claim 9, And a horizontal and vertical synchronization signal detected by the synchronization signal detector, wherein the APL value is 1% or more and 20% or less, wherein the frequency and number of pulses of the sustain drive waveform are maximized. . The method of claim 9, When there are horizontal and vertical synchronization signals detected by the synchronization signal detector and the APL value is greater than 20% and less than 100%, the frequency and the number of pulses of the sustain driving waveform decrease linearly, and the minimum value when the APL value reaches 100%. Sustain drive device of the plasma display panel characterized in that the. Storing an image signal input from an external source; Calculating an APL value using the video signal; Processing the video signal according to the APL value; A synchronization signal detecting step of determining the presence or absence of horizontal and vertical synchronization signals of the video signal; Comparing the APL value with a synchronization signal detection result value; A sustain frequency control step of controlling a frequency of a sustain driving waveform according to the comparison result value; And And a sustain timing and a pulse control step of controlling the timing of applying the sustain driving waveform and the pulse of the sustain driving waveform in accordance with the result value of the sustain frequency control step. The method of claim 13, And in the absence of the horizontal and vertical synchronizing signals detected in the synchronizing signal detection step, the frequency of the sustain driving waveform is minimized. The method of claim 13, And the horizontal and vertical synchronizing signals detected in the synchronizing signal detecting step and setting the frequency of the sustain driving waveform to a maximum value when the APL value is 1% or more and 20% or less. The method of claim 13,  If there is a horizontal and vertical synchronization signal detected in the synchronization signal detection step and the APL value is more than 20% and less than 100%, the frequency of the sustain driving waveform decreases linearly and becomes the minimum when the APL value reaches 100%. A sustain driving method of a plasma display panel, characterized in that. Storing an image signal input from an external source; Calculating an APL value using the video signal; Processing the video signal according to the APL value; A synchronization signal detecting step of determining the presence or absence of horizontal and vertical synchronization signals of the video signal; Comparing the APL value with a synchronization signal detection result value; A sustain pulse number control step of controlling the number of pulses of the sustain drive waveform according to the comparison result value; And And a sustain timing and pulse control step of controlling the application timing of the sustain driving waveform and the pulses of the sustain driving waveform in accordance with the result value of the sustain pulse number control step. The method of claim 17, And in the absence of the horizontal and vertical synchronization signals detected in the synchronization signal detection step, the number of pulses of the sustain driving waveform is set to a minimum value. The method of claim 17, And the pulse number of the sustain driving waveform is maximized when there are horizontal and vertical synchronization signals detected in the synchronization signal detecting step and the APL value is 1% or more and 20% or less. The method of claim 17, When there are horizontal and vertical synchronization signals detected in the synchronization signal detection step and the APL value is more than 20% and less than 100%, the number of pulses of the sustain driving waveform decreases linearly, and when the APL value reaches 100%, the minimum value is And a sustain driving method of the plasma display panel. Storing an image signal input from an external source; Calculating an APL value using the video signal; Processing the video signal according to the APL value; A synchronization signal detecting step of determining the presence or absence of horizontal and vertical synchronization signals of the video signal; Comparing the APL value with a synchronization signal detection result value; A sustain frequency control step of controlling a frequency of a sustain driving waveform according to the comparison result value; A sustain pulse number control step of controlling the number of pulses of the sustain drive waveform according to the comparison result value; And And a sustain timing and pulse control step of controlling a sustain driving waveform and a timing of applying the sustain driving waveform according to the result of the sustain frequency control step and the sustain pulse number controlling step. Driving method. The method of claim 21, And in the absence of the horizontal and vertical synchronization signals detected in the synchronization signal detecting step, the frequency and the number of pulses of the sustain driving waveform are minimized. The method of claim 21, If there is a horizontal and vertical synchronization signal detected in the synchronization signal detection step and the APL value is 1% or more and 20% or less, the sustain drive of the plasma display panel is characterized in that the frequency and the number of pulses of the sustain drive waveform are maximized. Way. The method of claim 21, When there are horizontal and vertical synchronization signals detected in the synchronization signal detection step and the APL value is more than 20% and less than 100%, the frequency and the number of pulses of the sustain driving waveform decrease linearly, and when the APL value becomes 100%. A sustain driving method of a plasma display panel, characterized in that the minimum value.

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