KR20000008125U - A driving device of a plasma display panel - Google Patents

Abstract

The present invention relates to a driving apparatus for a plasma display panel (PDP) in which the frequency and the number of sustain pulses are adjusted in accordance with a standard image level (APL) of an input video signal.

In the present invention, the PDP 10, in which the discharge cells in which the vertical electrode lines R1 to B640 and the horizontal electrode lines S1 to S480 form a matrix, emits light and displays an image is formed on the horizontal electrode lines S1 to S480 A scan and sustain driver 30 for supplying a scan pulse and a sustain pulse, and an address driver for supplying a bit value of the digital image data corresponding to the horizontal electrode lines S1 to S480 to the vertical electrode lines R1 to B640, (50), comprising: a level determination unit (101) which receives the digital image data and determines a corresponding level among predetermined multi-level average image levels (APL) and outputs a level selection signal; The scan frequency and the number information stored in the data table according to the storage address designation of the scanning and sustain driver 30, which receives the level selection signal from the level determination unit 130, And a ROM (ROM) 102 for outputting the data to the sustain driver 30.

Description

A driving device of a plasma display panel

The present invention relates to a plasma display panel (PDP), and more particularly, to a PDP driving apparatus in which the frequency and the number of sustain pulses are adjusted according to a standard video level (APL) of an input video signal.

As is well known, a PDP displays a moving picture or a still picture using a gas discharge phenomenon. First and second sustain electrodes and address electrodes are formed on upper and lower glass substrates, respectively. Is divided into a plurality of cells, and an image is displayed by a discharge selectively occurring in each cell.

Here, the address discharge refers to the discharge between the address electrode and the sustain electrode, the sustain discharge refers to the discharge between the first and second sustain electrodes, and the sustain discharge serves to sustain the address discharge.

FIG. 1 is a block diagram of a plasma display panel driving apparatus according to the related art. Referring to FIG. 1, the plasma display panel driving apparatus includes 640 R, G, and B address electrode lines R1, G1, B1, ..., R640, G640, (Hereinafter, referred to as vertical electrode lines) and 480 pairs of first and second sustain electrode lines (S1, S2, ..., S479, S480, hereinafter referred to as horizontal electrode lines) (R), green (G) and blue (B) digital image data (256 gradation implementation) by digitizing R, G and B image data and outputs various control A scan pulse is supplied to 480 horizontal electrode lines S1 to S480 according to a control signal of the microcomputer 20 to sequentially scan one line at a time, A sustain pulse is supplied to the electrode lines (S1 to S480) to sustain discharge and light emission of each cell. A memory unit 40 for storing the R, G, and B digital image data output from the microcomputer 20 by frame, color, and bit, a scanning and sustain driver 30 G, and B digital image data corresponding to the horizontal electrode lines scanned by 640 R, G, and B vertical electrode lines (R1 to B640) from the memory unit 40 And an address driver 50 for supplying the address signals.

The PDP 10 includes 480 horizontal electrode lines S1 to S480 formed on the front substrate and a plurality of horizontal electrode lines S1 to S480 and a plurality of horizontal electrode lines S1 to S480 on a rear substrate disposed parallel to the front substrate, (640 × 480 pixels (pixels, R, G, and B cells) in the form of a matrix) formed of 640 R, G, and B vertical electrode lines (R1 to B640)

The scan and sustain driver 30 includes a clock and data generator 31 for generating and outputting a clock signal CLK and a data signal D _o according to a control signal of the microcomputer 20, ) the clock signal (CLK) and a data signal (D _O) in the sustain pulse generating unit 32 that generates an output a sustain pulse in response to a control signal, is connected with the electrode line 480 horizontally (S1~S480) with And a driving IC (Integrated Circuit) 33 for sequentially supplying scan pulses to 480 horizontal electrode lines (S1 to S480) in accordance with the sustain pulses and then supplying sustain pulses at the same time.

Meanwhile, the driving method of the plasma display panel is roughly classified into a sub-field driving method and a sub-frame driving method. Of these, a plasma display device configured as described above according to a sub-field driving method displays a 256-gradation image on a PDP screen The following is an explanation.

In order to realize 2 ^x gradation, the sub-field driving method divides one frame picture into Y sub-field pictures, digitizes the externally input picture data into X-bit digital picture data, and supplies it to the PDP. However, X > Y)

Each of the subfields includes a reset period, an address period, and a sustain period. Among the reset period and the address period, the reset period and the address period are equally allocated to each subfield. However, the sustain period includes a bit weight So that it is possible to implement the gradation of the image by using the combination of the subfields (using the integration effect of the eyes).

That is, as shown in FIG. 2, one frame is divided into eight subfields SF1 to SF8, and brightness values proportional to 1: 2: 4: 8: 16: 32: 64: An image corresponding to the gradation data 0 to 255 is displayed by a combination of several subfields.

Accordingly, the microcomputer 20 digitizes the R, G, and B image data input from the outside for the implementation of 256 gradations and outputs 8-bit R, G, B digital image data (the most significant bit value B1 to the least significant bit value B8) And outputs various control signals required for driving the PDP 10 according to the digital image data and the external signal.

At this time, the 8-bit R, G, and B digital image data output from the microcomputer 20 are stored in the memory unit 40 by frame, color, and bit.

Thereafter, in the reset period and the address period of the first to eighth subfield screens SF1 to SF8, the drive IC 33 sequentially applies the wall charges generated in the previous field to all the horizontal electrode lines S1 to S480 in one step A write pulse for forming uniform wall charges on the entire surface of the three-electrode surface discharge PDP 10 in two stages, and an erase pulse in three stages again to supply 640 R, G, and B vertical electrodes line (R1~B640) so as to form wall charges on the lower the voltage of the address pulse supplied to the later, and the clock signal (CLK) and a data signal (D _O) and 480 horizontal electrode lines in accordance with the sustain pulse to step The scanning of 480 horizontal electrode lines (S1 to S480) is completed when a scan pulse is sequentially supplied to the scan electrodes (S1 to S480) one by one.

The address driver 50 supplies the address pulse (1 bit value of R, G, B digital image data) corresponding to the horizontal electrode line to which the scan pulse is supplied to scan the scan signal 640 are supplied to the 640 R, G, and B vertical electrode lines (R1 to B640), respectively, so that a discharge occurs in the discharge space of each cell supplied with the logic "high" as the address pulse.

At this time, the address driver 50 outputs 8 bits of R, G, B digital image data (B1 to B8) corresponding to each cell as B1 to SF1, B2 to SF2, B7? SF7, and B8? SF8, respectively.

On the other hand, when the address period of each of the subfield screens SF1 to SF8 is completed, the driving IC 33 receives the sustain pulse from the sustain pulse generating portion 32 and applies SF1: SF2: SF2 to all the horizontal electrode lines S1 to S480, ... SF7: SF8 = 2 ⁷ : 2 ⁶ : ... 2 ^1: 2 ⁰ (brightness relative ratio) supplies the sustain pulses of the number proportional to That is, the most significant bit (MSB) of time T during the low-order bit are, respectively, T / 2, T / 4, the near-bit in order from MSB ... T / 64, and T / 128 so that the discharge and light emission of some of the cells in which the discharge is generated in the address period is maintained during the period (sustain period) during which the sustain pulse is supplied.

After completion of the construction of the first to 8th subfield screens SF1 to SF8 through the above process, 256-gradation images are displayed on the 3-electrode surface discharge PDP 10.

However, in the conventional PDP driving apparatus, the sustain pulse is generated in the sustain pulse generating unit 32 according to the control signal of the microcomputer 20 as described above, and the driving IC 33, which receives the sustain pulse, The number of sustain pulses proportional to the luminance contrast for each field is supplied to all the horizontal electrode lines (S1 to S480).

That is, the frequency and the number of the sustain pulses can not be changed in a preset state.

Therefore, conventionally, when the PDP is turned on for a long period of time, the temperature of the panel is excessively increased to cause the panel to rupture or to operate abnormally.

In other words, when the sustain period is short or the number of sustain pulses is large, the current flowing through the panel increases and the temperature rises. The color of the unit cell does not come out properly; The color coordinates may change; The brightness changes; Turning on and off cells can be changed; The panel could be ruptured at uneven temperature in each region.

Therefore, the present invention has been proposed in order to solve the above problems of the prior art, and it is an object of the present invention to provide a PDP capable of preventing the abnormal operation of the panel by adjusting the frequency and the number of the sustain pulse according to the standard image level (APL) And an object of the present invention is to provide a driving apparatus for the same.

Technical Solution According to an aspect of the present invention, there is provided a plasma display apparatus including a plasma display panel (PDP) in which a discharge cell having a matrix of a vertical electrode line and a horizontal electrode line emits light to display an image, a scanning circuit for supplying a scan pulse and a sustain pulse to the horizontal electrode line, A sustain driver, and an address driver for supplying a bit value of the digital image data to the vertical electrode line; The scan and sustain driver includes a clock and data generator for generating a clock signal and a data signal, a sustain pulse generator for generating a sustain pulse, and a drive IC for driving a horizontal electrode line in accordance with a clock signal, a data signal and a sustain pulse A driving apparatus for a PDP, comprising: A level determining unit for receiving the digital image data and determining a corresponding level among preset multi-level average image levels (APL); And a memory for outputting the sustain frequency and the number information stored in the data table to the sustain pulse generator in accordance with the memory address designation of the sustain pulse generator input from the level selection unit.

1 is a block diagram of a conventional plasma display panel driving apparatus.

Fig. 2 is a diagram showing a frame structure of a conventional sub-field driving method.

3 is a block diagram of a plasma display panel driving apparatus according to the present invention;

4 is a flowchart illustrating a method of driving a plasma display panel according to the present invention.

DESCRIPTION OF THE REFERENCE SYMBOLS

10: Plasma display panel (PDP) 20: Microcomputer

30: scanning and sustain driver 32: sustain pulse generator

40: memory unit 50: address driver

101: level determining section 102: ROM (ROM)

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

FIG. 3 is a block diagram of a PDP driving apparatus according to the present invention. In FIG. 3, a discharge cell in which a matrix of a vertical electrode line (R1 to B640) and a horizontal electrode line (S1 to S480) 10, and digital image data obtained by digitizing R, G, and B image data input from the outside and outputting R, G, and B digital image data, A scan and sustain driver for supplying a scan pulse and a sustain pulse to the horizontal electrode lines S1 to S480 according to a control signal of the microcomputer 20 to emit light of each cell, A memory unit 40 for storing the R, G and B digital image data output from the microcomputer 20 by frame, color, and bit, and a driving unit 30 for driving the scanning and sustain driving unit 30 The horizontal electrode lines S1 to S And an address driver 50 for reading the bit values of the R, G and B digital image data corresponding to the scan electrodes 480 and 480 from the memory unit 40 and supplying the read bit values to the vertical electrode lines R 1 to B 640, The driving unit 30 includes a clock and data generating unit 31 for generating and outputting a clock signal CLK and a data signal D _o according to a control signal of the microcomputer 20, a pulse generating section 32, the clock signal (CLK) and a data signal (D _O) and a driving IC (33) for supplying a scan pulse and a sustain pulse to the horizontal electrode lines (S1~S480) according to the sustain pulse A driving apparatus for a PDP includes a level determining unit for receiving R, G, and B digital image data from the microcomputer 20, determining a corresponding level among predetermined multi-level average image levels (APL) (101), the level determination unit (1) (ROM) 102 for outputting the sustain frequency and the number information stored in the data table to the sustain pulse generating unit 32 according to the storage address designation of the sustain pulse generating unit 32, ).

The operation and effect of the present invention will be described with reference to FIGS. 3 and 4. FIG.

First, the microcomputer 20 digitizes R, G, and B image data input from the outside in order to realize 256 gradations and outputs 8-bit R, G, and B digital image data (most significant bit value B1 to least significant bit value B8) And outputs various control signals required for driving the PDP 10 according to the digital image data and the external signal.

At this time, the level determining unit 101 receives the R, G, and B digital image data output from the microcomputer 20, and receives a value of a predetermined gradation or more from R, G, and B digital image data corresponding to each frame, Determines the level of the APL (φ level to n level) set in advance and outputs a level selection signal (ST1 to ST2).

The sustain pulse generating unit 32 in the scanning and sustain driving unit 30 receives the level selection signal and designates a memory address of the ROM 102 according to the APL level. The RAM 102, And outputs the sustain frequency and the number information recorded in the corresponding address of the data table to the sustain pulse generating unit 32. (ST3)

For example, as shown in Table 1 below, when eight frames of APL mode are used, when each frame is divided into eight subfields, 64 types (8 × 8) of the sustain frequency and the number information are stored in the ROM 102 And stored.

Herein, information on the frequency of the sustain pulse is stored for a time width of the corresponding frequency, and information on the number of sustain pulses is a " high " signal at a certain point in the cycle, Quot; low " signal.

<Table 1>

φ level SF1, Sustain Frequency and Count SF2, sustain frequency and number ... SF8, Sustain Frequency and Count Level 1 SF1, Sustain Frequency and Count SF2, sustain frequency and number ... SF8, Sustain Frequency and Count ... ... 7th level SF1, Sustain Frequency and Count SF2, sustain frequency and number ... SF8, Sustain Frequency and Count

Thereafter, the sustain pulse generating unit 32, which reads the sustain information from the ROM 102, generates and outputs a sustain pulse, and the drive IC 33 receiving the sustain pulse generates the sustain pulse in the clock and data generating unit 31 supplying a sustain pulse to the clock signal (CLK) and a data signal (D _O) every horizontal electrode lines (S1~S480) after supplying the scan signal lines one by one in sequence to a horizontal electrode lines (S1~S480) according to And the scanning is completed. (ST4)

In addition, in supplying the scan pulse, the address driver 50 supplies the address pulses corresponding to the horizontal electrode lines (S1 to S480) supplied with the scan pulses to the vertical electrode lines (R1 to B640) in synchronization with the scan signals So that the discharge is generated in the discharge space of each cell supplied with the logic " high " with the address pulse.

After completion of the construction of the first to 8th subfield screens SF1 to SF8 through the above process, 256-gradation images are displayed on the 3-electrode surface discharge PDP 10.

As described above, since the number and frequency of the sustain pulses are variable depending on the standard image level (APL) of the input image signal, when the PDP is turned on for a long time, the temperature of the panel is excessively increased There is an effect that the color of the unit cell does not come out properly, the color coordinates change, the brightness changes, the cell that is turned on and off, and the panel is prevented from being ruptured at an uneven temperature in each region.

Claims (1)

A plasma display panel (PDP) in which a discharge cell having a matrix of a vertical electrode line and a horizontal electrode line emits light to display an image, a scanning and sustain driver for supplying a scan pulse and a sustain pulse to the horizontal electrode line, And an address driver for supplying a bit value of the vertical electrode line to the vertical electrode line; The scan and sustain driver includes a clock and data generator for generating a clock signal and a data signal, a sustain pulse generator for generating the sustain pulse, and a scan driver for driving the horizontal electrode line according to the clock signal, A driving apparatus for a PDP having a driving IC (IC) A level determination unit for receiving the digital image data and determining a corresponding level among predetermined multi-level average image levels (APL); And a memory for outputting the sustain frequency and the number information stored in the data table to the sustain pulse generating unit in accordance with a storage address designation of the sustain pulse generating unit which receives the level select signal from the level determining unit. Device.