KR100603460B1 - Method and apparatus for driving electro-luminescensce dispaly panel - Google Patents

Abstract

The present invention relates to a driving method and apparatus for an organic EL display panel which enables an aging operation even during driving.

An EL display panel driving method of the present invention has a scan period for emitting EL cells formed at intersections of a plurality of scan lines and a plurality of data lines, and a multi-step voltage difference between adjacent scan lines while plotting the plurality of data lines. And an aging period for causing the EL cells to self-age.

Description

TECHNICAL AND APPARATUS FOR DRIVING ELECTRO-LUMINESCENSCE DISPALY PANEL}             

1 is an equivalent view of a conventional passive matrix organic EL display device.

FIG. 2 is a drive waveform diagram of the EL panel shown in FIG. 1;

3 is a driving waveform diagram illustrating a method of driving an organic EL display panel according to an exemplary embodiment of the present invention.

4 is another scan drive waveform diagram in the aging period of the present invention;

5A and 5B show another scan drive waveform in the aging period of the present invention.

6A and 6B show another scan drive waveform in the aging period of the present invention.

7 illustrates an organic EL display panel driving apparatus according to an embodiment of the present invention.

FIG. 8 is a drive waveform diagram of the drive device shown in FIG. 7. FIG.

9 illustrates an organic EL display panel driving apparatus according to another exemplary embodiment of the present invention.

FIG. 10 is a drive waveform diagram of the drive device shown in FIG. 9; FIG.

<Brief description of symbols for the main parts of the drawings>

20, 30: EL panel 22, 32, 52: scan driver

24, 34: data driver 26, 36: EL cell

40, 60: shift register 42, 62: level shifter portion

ST1 to STn: first to nth stages

DST1 to DSTk: first to kth dummy stages

LS1 to LSn: first to nth level shifters

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electro-luminescence display device, and more particularly, to a method and apparatus for driving an electro-luminescence display device that enables an aging operation during driving.

Various flat panel display devices that can reduce weight and volume, which are disadvantages of cathode ray tubes, are emerging. Such flat panel displays include a liquid crystal display, a field emission display, a plasma display panel, and an electro-luminescence (hereinafter, EL). And a display panel.

Among them, an EL display panel is a self-luminous element that emits a phosphor by recombination of electrons and holes, and is classified roughly into an inorganic EL using an inorganic compound and an organic EL using an organic compound as the phosphor. Such EL display panels have many advantages such as low voltage driving, self-luminous, thin film type, wide viewing angle, fast response speed, and high contrast, and are expected to be the next generation display devices.

The organic EL device is composed of an anode formed of a transparent conductive material on a substrate, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and a cathode formed of a metal having a low work function, stacked on the substrate with an organic material. . When a forward voltage is applied between the anode and the cathode, electrons generated from the cathode move toward the emission layer through the electron injection layer and the electron transport layer, and holes generated from the anode move toward the emission layer through the hole injection layer and the hole transport layer. Accordingly, the light emitting layer emits light by recombination of electrons and holes supplied from the electron transporting layer and the hole transporting layer. At this time, the luminance of the organic EL element is proportional to the current flowing between the anode and the cathode.

FIG. 1 is an equivalent view of a passive matrix type EL display device in which the organic EL elements are arranged in a matrix form, and FIG. 2 is a driving waveform diagram of the EL panel 20 shown in FIG. .

The EL display device shown in FIG. 1 includes an EL panel 20 including EL cells 26 formed at each intersection of scan lines SL1 to SLn and data lines DL1 to DLm, and scan lines SL1 to SLn. Scan driver 22 for driving?) And data driver 24 for driving data lines DL1 to DLm.

 Each of the EL cells 26 formed in the EL panel 20 is represented by a diode connected in the forward direction between the data line DL which is equivalently an anode and the scan line SL which is an anode. Each of the EL cells 26 has a negative scan pulse, that is, a scan low voltage Vlow, is supplied to the scan line SL, and a positive data signal (current) is supplied to the data line DL, as shown in FIG. 2. When the forward voltage is applied, light is emitted to generate light corresponding to the data signal. On the other hand, each of the EL cells 26 does not emit light when the scan high voltage Vhigh is supplied to the scan line SL and the reverse voltage is applied.

The scan driver 22 sequentially supplies scan pulses to the n scan lines SL1 to SLn as shown in FIG. 2. In other words, the scan driver 22 sequentially supplies the scan low voltages Vlow to the scan lines SL1 through SLn to sequentially enable the scan lines SL1 through SLn, and the scan high voltage in the remaining period. Supply (Vhigh) to disable. In addition, the scan driver 22 repeats the sequential driving of the scan lines SL1 to SLn for each frame F. FIG.

The data driver 24 supplies a data signal to m data lines DL1 to DLm every time the scan lines SL1 to SLn are enabled.

Such a conventional organic EL display device undergoes an aging process for causing the EL cells 26 to be reverse biased during the manufacturing process for stable driving. However, even though the aging process is performed during the manufacturing process, the EL cells 26 are deteriorated as the driving time elapses, resulting in a shortened life or a line defect such as a short defect due to stress. . In order to solve this problem, an aging operation is required even while the organic EL display device is being driven.

Accordingly, it is an object of the present invention to provide a method and apparatus for driving an organic EL display panel which enables an aging operation even during driving.

In order to achieve the above object, a method of driving an EL display panel according to the present invention includes a scan period for emitting EL cells formed at each intersection of a plurality of scan lines and a plurality of data lines, and adjacent to the plurality of data lines while plotting them. And an aging period in which the EL cells are self-aging by having a multi-step voltage difference between scan lines.

In the aging period, a multi-stage aging voltage is applied to the adjacent scan lines in the order opposite to each other.

The aging period further includes a neutralizing step of applying the same aging voltage to the adjacent scan line.

In the aging period, a multi-stage aging voltage is applied to the scan line to sequentially increase or decrease the voltage difference between the odd scan line and the even scan line.

In the aging period, a multi-stage aging voltage is applied to the scan line to sequentially increase or decrease the voltage difference between the odd scan line and the even scan line.

In the aging period, an aging voltage that is varied in multiple steps to the odd scan line is applied to the even scan line, and an aging voltage that is varied in the order opposite to the odd scan line is applied.

In the aging period, a multi-stage aging voltage that sequentially increases to one of the odd scan line and the even scan line is sequentially applied to the other scan line.

In the aging period, a multi-stage aging voltage that sequentially increases and decreases to one of the odd scan lines and the even scan lines is sequentially applied to the remaining scan lines and then increases.

In the aging period, a multi-stage aging voltage that is sequentially increased or decreased is sequentially applied to any one of the odd scan line and the even scan line, and a constant voltage is applied to the remaining scan lines.

In the aging period, a multi-stage aging voltage is sequentially applied to one of the odd scan lines and the even scan lines, and then sequentially decreased or sequentially decreased, and a constant voltage is applied to the remaining scan lines.

The constant voltage applied in the aging period is the same voltage as the lowest aging voltage among the multi-level aging voltages.

The constant voltage applied in the aging period is the same voltage as the scan low voltage supplied as an enable voltage to the scan line in the scan period.

The aging period further includes a neutralization step of applying the same aging voltage to the odd and even scan lines.

In the neutralizing step, the odd and even scan lines are equalized to an intermediate voltage among the multi-level aging voltages.

The multi-stage aging voltage is a multi-stage voltage between the highest aging voltage greater than or equal to the scan high voltage supplied to the scan line and the lowest aging voltage such as the scan low voltage supplied to the enable voltage in the scan period. The voltage divided by.

The multi-stage aging voltage is repeated within the aging period.

The scan period and the aging period are repeated every frame.

In addition, the driving apparatus of the EL display panel according to the present invention comprises: a data driver for plotting a data signal on a data line in a scan period and a data line in an aging period; A scan driver for causing a scan pulse on a scan line in the scan period and a multi-step voltage difference between adjacent scan lines in the aging period; An EL cell formed at each intersection of the scan line and the data line, the EL cell having an EL display panel that emits light according to the data signal in the scan period and self-ages in the aging period.

The scan driver applies a multi-stage aging voltage that varies in the order opposite to each other in the adjacent scan line in the aging period.

The scan driver further includes a neutralization step of applying the same aging voltage to the adjacent scan line within the aging period.

The scan driver applies a multi-stage aging voltage to the scan line to sequentially increase or decrease the voltage difference between the odd scan line and the even scan line in the aging period.

The scan driver applies a multi-stage aging voltage to the scan line during the aging period so that the voltage difference between the odd scan line and the even scan line increases and decreases or decreases and then increases.

The scan driver applies an aging voltage that is varied in multiple stages to the odd scan line in the aging period, and an aging voltage that varies in the order opposite to the odd scan line to the even scan line.

The scan driver applies a multi-stage aging voltage that sequentially increases to one of the odd scan line and the even scan line and a multi-stage aging voltage that sequentially decreases the remaining scan lines in the aging period.

The scan driver applies a multi-stage aging voltage that sequentially increases and decreases in one of the odd scan lines and the even scan lines, and increases and decreases the multi-stage aging voltage sequentially in the remaining scan lines.

The scan driver applies a multi-stage aging voltage that sequentially increases or decreases to any one of the odd scan line and the even scan line in the aging period, and applies a constant voltage to the remaining scan lines.

The scan driver applies a multi-stage aging voltage that sequentially increases and decreases or decreases sequentially and then increases to any one of the odd scan line and the even scan line in the aging period, and applies a constant voltage to the remaining scan lines. do.

The scan driver further includes a neutralization step in which the same aging voltage is applied to the odd and even scan lines within the aging period.

The scan driver applies the same intermediate voltage among the multi-stage aging voltages to the odd and even scan lines in the neutralization step.

The scan driver has a multi-step voltage in the scan period between a highest aging voltage greater than or equal to the scan high voltage supplied to the scan line and a minimum aging voltage such as the scan low voltage supplied to the enable voltage. The voltage is divided and supplied to the multi-stage aging voltage.

The scan driver repeatedly supplies the multi-stage aging voltage within the aging period.

The scan driver repeats the scan period and the aging period every frame.

The scan driver may include a plurality of stages for shifting start pulses to supply the respective output signals and the next stage start pulses, and a plurality of dummy stages for shifting the output signals of the last stage of the stages to secure the aging period. A shift register; Level shifting each of the output signals of the shift register to supply the scan pulse to the scan line in the scan period, and a plurality of levels for supplying the multilevel aging voltage to have the multistep voltage difference to the adjacent scan line in the aging period. And a level shifter portion having a shifter.

Alternatively, the scan driver may include: a shift register having a plurality of stages for shifting start pulses and supplying each output signal to a next stage start pulse; Level shifting each of the output signals of the shift register to supply the scan pulse to the scan line in the scan period, and to supply the multi-level aging voltage to have the multi-step voltage difference to the adjacent scan line in the aging period in the aging period. And a level shifter portion having a plurality of level shifters.

The start pulse of the next frame is delayed and supplied so that the aging period can be included after the scan period.

Each of the plurality of stages supplies an enable signal corresponding to the shifted start pulse, and the level shifter unit supplies the multi-level aging voltage by synchronizing the aging period with the period during which the enable signal is output from each dummy stage. Variable.

Other objects and advantages of the present invention in addition to the above object will become apparent from the description of the preferred embodiment of the present invention with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to FIGS. 3 to 12.

3 illustrates driving waveforms of a scan line and a data line to explain a driving method of an organic EL display device according to an exemplary embodiment of the present invention.

The driving method of the organic EL display device according to the embodiment of the present invention includes an aging period APD for aging the EL panel during driving. For example, as shown in FIG. 3, one frame Fi causes a scan period SPD for emitting EL cells sequentially in line, and an aging period for causing EL cells to self-age due to the voltage difference between two adjacent scan lines. APD). For this purpose, the period of the frame Fi is increased to secure an aging period APD separate from the scan period SPD.

In the scan period SPD of one frame Fi, a negative scan pulse, that is, a scan low voltage Vlow, is sequentially supplied to the n scan lines SL1 through SLn, and the first scan high voltage ( Vhigh1) is supplied. The m data lines DL1 to DLm are supplied with positive data signals (for example, currents) every time the scan low voltage Vlow is supplied. Accordingly, the EL cells to which the forward voltage is applied by the scan low voltage Vlow and the positive data signal emit light to generate light rising to the data signal, while the reverse voltage is caused by the first scan high voltage Vhigh1. These applied EL cells do not emit light.

In the aging period APD subsequent to the scan period SPD, the EL cells have their own states by floating the data lines DL1 through DLm while allowing the scan lines SL1 through SLn to have voltage differences with adjacent scan lines. Depending on the voltage it is self-aging. In particular, self-aging by supplying an aging voltage that varies in multiple stages to have a voltage difference between the odd scan lines SL1, SL3,..., SLn-1 and the even scan lines SL2, SL4, .., SLn. The efficiency is improved, and as a result, the EL cells can be further stabilized.

For example, as illustrated in FIG. 3, scan low voltages are applied to the odd scan lines SL1, SL3,..., SLn-1 during the first to fifth steps A1 to A5 in the aging period APD. An aging voltage that varies from (Vlow)-> intermediate voltage (Vmiddle)-> second scan high voltage (Vhigh2)-> intermediate voltage (Vmiddle)-> scan low voltage (Vlow) is supplied. At this time, in the even scan lines SL2, SL4,..., And SLn, the second scan high voltage Vhigh2-> intermediate voltage Vmiddle is opposite to the odd scan lines SL1, SL3,..., SLn-1. An aging voltage that varies from scan low voltage Vlow to middle voltage second scan high voltage Vhigh2 is supplied. Here, the second scan high voltage Vhigh2 which is the high aging voltage is set to be greater than or equal to the first scan high voltage Vhigh1 that has been applied in the scan period SPD. For example, the second scan high voltage Vhigh2 is set to a voltage that is approximately 10-20% greater than the first scan high voltage Vhigh1. In this aging period APD, the data lines DL1 to DLm are floated.

Accordingly, the EL cells in which the data lines DL1 to DLm are floated are adjacent scan lines, that is, the odd scan lines SL1, SL3,... SLn-1 and the even scan lines SL2, SL4,. Self-aging by the voltage difference between SLn). In addition, in the aging period APD, the voltages of the odd scan lines SL1, SL3, ..., SLn-1 and the even scan lines SL2, SL4, ..., SLn are set to the intermediate voltage Vmiddle. It will include a neutralization step that becomes identical. By this neutralization step, parasitic capacitors formed inside the EL panel can be reduced.

In addition, the driving waveforms that may be supplied to the scan lines SL1 to SLn in the aging period APD of the present invention are varied as shown in FIGS. 4 to 6B.

Referring to FIG. 4, in the aging period APD, the aging voltages AV1 to AV vary from the first to the second steps A1 to A2i during the odd scan lines SL1, SL3,..., SLn-1; SLodd. AVi has an aging voltage AVi to variable in the first to second i steps A1 to A2i in the direction opposite to the odd scan line SLodd in the even scan lines SL2, SL4,..., SLn; AV1) is supplied.

Specifically, the odd scan line SLodd decreased in the order AV1-> AV2-> ...-> AVi-1-> Ai over the first to second steps A1 to A2i of the aging period APD. An aging voltage which is increased again in the order of AVi-1-> ...-> AV2-> AV1 is supplied. In contrast, the even scan line SLeven increases in the order AVi-> AVi-1-> ...-> AV2-> AV1, and then again in the order AV2-> ...-> AVi-1-> AVi. A decreasing aging voltage is supplied. Accordingly, the voltage difference between the odd and even scan lines SLodd and SLeven varies for each of the first to second i steps A1 to A2i. In other words, as shown in FIG. 4, the voltage difference between the odd and even scan lines SLodd and SLeven is sequentially decreased in the first to i th steps A1 to Ai, and the i + 1 to second i i steps (Ai +). 1 to A2i), the voltage difference is sequentially increased so that the EL cells are effectively self-aging. In addition, in contrast to FIG. 4, when the aging voltages Al to Ai are supplied to the odd and even scan lines SLodd and SLeven, the voltage difference between the odd and even scan lines SLodd and SLeven increases sequentially. Decreases, causing the EL cells to self-aging effectively.

The aging period APD is at least a neutralization step of reducing parasitic capacitors in the EL panel by making the odd and even scan lines SLodd and SLeven equal to the middle aging voltage among the aging voltages A1 to Ai of the multi-stage. It will be included once.

In addition, the multi-level aging voltages AV1 to AVi are supplied to only one of the odd and even scan lines SLodd and SLeven, as shown in FIGS. 5A to 6B, and the remaining scan lines are provided with the lowest aging voltage AV1, That is, the case may be fixed when the scan low voltage Vlow is fixed.

In detail, as illustrated in FIG. 5A, the even scan line SLeven is fixed to the scan low voltage Vlow, and the first scan line SLodd is connected to the first through second steps A1 through A2i through AV1-> AV2->. ...-> AVi-1-> Ai-> AVi-1-> ...-> AV2-> AV1, or AVi-> AVi-1-> ...-> AV2- as shown in FIG. 5B. An aging voltage that varies in the order of> AV1-> AV2-> ...-> AVi-1-> AVi is supplied.

On the contrary, as shown in FIG. 6A, the odd scan line SLodd is fixed to the scan low voltage Vlow, and AVeven-> AV2-> is applied to the even scan line SLeven through the first to second steps A1 to A2i. ..-> AVi-1-> Ai-> AVi-1-> ...-> AV2-> AV1 or AVi-> AVi-1-> ...-> AV2-> as shown in FIG. An aging voltage that varies from AV1-> AV2-> ...-> AVi-1-> AVi is supplied.

Accordingly, the voltage difference between the odd and even scan lines SLodd and SLeven varies for each of the first to second i steps A1 to A2i. In other words, as shown in FIGS. 5A and 6B, in the first to second steps A1 to A2i, the EL cells effectively self-decrease as the voltage difference between the odd and even scan lines SLodd and SLeven decreases and then increases. Allow it to age. On the contrary, as shown in FIGS. 5B and 6A, the voltage difference between the odd and even scan lines SLodd and SLeven increases and decreases sequentially, thereby allowing the EL cells to effectively self-age.

The aging period APD is equal to the lowest aging voltage AVi among the aging voltages A1 to Ai, that is, the scan low voltage Vlow, so that the odd and even scan lines SLodd and SLeven are the same. It includes at least once a neutralizing step to reduce the internal parasitic capacitor.

Furthermore, in the aging period APD of the present invention, it is also possible to repeat the above-described first to second steps.

As described above, in the method of driving the organic EL display device according to the embodiment of the present invention, the EL panel can be aged even during driving by securing an aging period APD in which all the EL cells are self-aging in multiple steps in one frame Fi. Will be. Therefore, the life of the EL panel can be extended and defects such as line defects due to stress can be prevented.

FIG. 7 shows a drive device of an organic EL display panel according to an embodiment of the present invention, and FIG. 8 shows drive waveforms of the drive device.

The driving device of the organic EL display panel shown in FIG. 7 includes an EL panel 30 including an EL cell 36 formed at each intersection of scan lines SL1 to SLn and data lines DL1 to DLm, and a scan line. And a scan driver 32 for driving the SL1 to SLn, and a data driver 34 for driving the data lines DL1 to DLm.

Each of the EL cells 36 formed in the EL panel 30 is represented by a diode connected in a forward direction between the data line DL which is equivalently an anode and the scan line SL which is an anode. When each of the EL cells 36 is supplied with the scan low voltage Vlow to the scan line SL and the positive data signal (current) is supplied to the data line DL in the scan period SPD, the forward voltage is applied. When the light is emitted to generate light corresponding to the data signal, and the reverse voltage is applied by the first scan high voltage Vhigh1, the light does not emit light. Each of the EL cells 36 has the odd scan lines SL1, SL3,... SLn-1 and even scan lines SL2, SL4, as the data lines DL1 to DLn are floated in the aging period APD. When SLn) has a voltage difference that varies in multiple steps, self-aging is performed without emitting light.

The data driver 24 supplies the data signals to the m data lines DL1 to DLm every time the scan lines SL1 to SLn are enabled in the scan period SPD. In the aging period APD, the data driver 24 supplies the data signals. Plot DL1 to DLm).

The scan driver 32 sequentially scans the scan low voltages Vlow in the n scan lines SL1 through SLn in the scan period SPD of one frame Fi, and the first scan high voltage in the remaining periods. Supply (Vhigh1). In addition, the scan driver 32 may perform the odd scan lines SL1, SL3,..., SLn-1 and even scan lines SL2, SL4, ..., SLn in the aging period APD of one frame Fi. ) Provides an aging voltage that is varied in multiple stages so that the voltage has multiple voltage differences.

To this end, the scan driver 32 outputs n output signals S1 to Sn while sequentially shifting the start pulse Vst input in units of frames Fi, and also secures an aging period APD. And a level shifter 42 for level shifting each of the output signals S1 to Sn of the shift register 40 and supplying them to the scan lines SL1 to SLn.

The shift register 40 shifts the n stages ST1 to STn for outputting the n output signals S1 to Sn and the nth stage STn output signal Sn while shifting the start pulse Vst. And k dummy stages DST1 to DSTk for ensuring an aging period APD.

The n stages ST1 to STn and the k dummy stages DST1 to DSTk are cascaded to the input line of the start pulse Vst and commonly connected to the input line of the clock signal CLK. The first to n-th stages ST1 to STn sequentially shift the start pulse Vst according to the clock signal CLK to shift the first to nth output signals S1 to Sn as shown in FIG. 8. 42). At this time, each of the output signals S1 to Sn of the n stages ST1 to STn is supplied to the start pulse input line of the next stage. The k dummy stages DST1 to DSTk sequentially shift the output signal STn of the nth stage STn according to the clock signal CLK. The output signals DS1 to DSk of each of the k dummy stages DST1 to DSTk are not output to the level shifter 42 but are supplied only to the start pulse input line of the next dummy stage. Accordingly, each frame Fi includes a scan period SPD in which the first to nth stages ST1 to STn sequentially output the low voltage output signals S1 to Sn, which are enable voltages, as shown in FIG. 8. In addition, a dummy period during which the dummy stages DST1 to DSTk sequentially output the low voltage output signals DS1 to DSk can be secured as the aging period APD. During this aging period (APD), the first to nth stages ST1 to STn all output high voltage output signals S1 to Sn.

The level shifter section 42 includes n level shifters LS1 to LSn connected between the n stages ST1 to STn and the n scan lines SL1 to SLn, respectively. The level shifters LS1 to LSn disable the scan low voltage Vlow when a low voltage, which is an enable voltage of the shift register 40 output signals S1 to Sn, is input in the scan period SPD as shown in FIG. 8. When a high voltage, which is a voltage, is input, the first scan high voltage Vhigh1 is selected and supplied to each of the scan lines SL1 to SLn. When the high voltages of the shift register 40 output signals S1 to Sn are input in the aging period APD as shown in FIG. 8, the level shifters LS1 to LSn receive the odd scan lines SL1, SL3,. An aging voltage that varies in the opposite direction to SLn-1) and even scan lines SL2, SL4, ..., SLn is applied in steps.

For example, as shown in FIGS. 3 and 8, Vod2-> Vmiddle-> Vlow-> is applied to the odd scan lines SL1, SL3, ..., SLn-1 through the first to fifth steps A1 to A5. Aging voltages varying in the order of Vmiddle-> Vhigh2, and are supplied to the even scan lines SL2, SL4, ..., SLn in order of Vlow-> Vmiddle-> Vhigh2-> Vmiddle-> Vlow, or from FIGS. As illustrated in FIG. 6B, the aging voltages AV1 to AVi that are varied in the first to second stages are supplied.

To this end, the level shifter 43 inputs and uses all the aging voltages AV1 to AVi in multiple stages, or inputs only the highest aging voltage AV1 and the lowest aging voltage AVi, and then divides the highest aging voltage into a divided resistor. AV1) is divided and used.

The multi-steps A1 to Ai dividing the aging period APD output a low voltage in which the dummy stages DST1 to DSTk of the shift register 40 are enabled voltages as shown in FIG. 8. It can be divided into a period.

FIG. 9 illustrates a driving apparatus of an organic EL display panel according to another exemplary embodiment, and FIG. 10 illustrates driving waveforms of the driving apparatus.

In the driving apparatus of the organic EL display panel shown in FIG. 9, the shift register 60 of the scan driver 52 has only n stages ST1 to STn without the dummy stage DST in contrast to the driving apparatus shown in FIG. 7. It has the same components except that it is provided. Therefore, description of overlapping components will be omitted.

The scan driver 52 sequentially outputs the n output signals S1 to Sn while shifting the start pulse Vst input in the unit of frame Fi, and the output of the shift register 40. And a level shifter 62 for level shifting each of the signals S1 to Sn and supplying them to each of the scan lines SL1 to SLn.

The n stages ST1 to STn included in the shift register 60 sequentially shift the start pulse Vst according to the clock signal CLK, so that the first to nth output signals S1 to Sn as shown in FIG. 10. Is output to the level shifter section 62, and each of the output signals S1 to Sn is supplied to the start pulse input line of the next stage. Accordingly, as shown in FIG. 10, the first to nth stages ST1 to STn sequentially output the low voltage output signals S1 to Sn. After the scan period SPD, the start time of the start pulse Vst of the next frame Fi + 1 is delayed so as to secure the aging period APD. During this aging period (APD), the first to nth stages ST1 to STn all output high voltage output signals S1 to Sn.

The n level shifters LS1 to LSn provided in the level shifter 62 have a scan low voltage when a low voltage of the shift register 60 output signals S1 to Sn is input in the scan period SPD as shown in FIG. 10. When the high voltage is input, Vlow is selected and supplied to the scan lines SL1 to SLn by selecting the first scan high voltage Vhigh1. When the high voltages of the shift registers 40 output signals S1 to Sn are input in the aging period APD as shown in FIG. 10, the level shifters LS1 to LSn receive the odd scan lines SL1, SL3,. An aging voltage that varies in the opposite direction to SLn-1) and even scan lines SL2, SL4, ..., SLn is applied in steps.

For example, as shown in FIG. 3 and FIG. 10, Vod2-> Vmiddle-> Vlow-> is applied to the odd scan lines SL1, SL3, ..., SLn-1 through the first to fifth steps A1 to A5. Aging voltages varying in the order of Vmiddle-> Vhigh2, and are supplied to the even scan lines SL2, SL4, ..., SLn in order of Vlow-> Vmiddle-> Vhigh2-> Vmiddle-> Vlow, or from FIGS. As illustrated in FIG. 6B, the aging voltages AV1 to AVi that are varied in the first to second stages are supplied.

Accordingly, in the aging period APD, the data lines DL1 to DLm have a multi-step voltage difference between adjacent scan lines, so that the entire EL cells 36 are self-aging. Thus, not only can the life of the EL panel 30 be extended, but also defects such as line defects can be prevented.

As described above, the method and apparatus for driving an EL display panel according to the present invention provide a period in which a whole of EL cells are self-aging due to a multi-step voltage difference between adjacent scan lines and a floating state of a data line, independently of the scan period during a frame. By securing it, the EL cells can be aged even during driving. Thus, not only the life of the EL display panel can be extended, but also defects such as line defects due to stress can be prevented.

In addition, by including at least once a neutralizing step of applying the same voltage to adjacent scan lines within the aging period, parasitic capacitors in the EL panel can be reduced.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (38)

A scan period for emitting EL cells formed at each intersection of the plurality of scan lines and the plurality of data lines, And an aging period for allowing the EL cells to self-age by having a multi-step voltage difference between adjacent scan lines while plotting the plurality of data lines. The method of claim 1, In the aging period And a multi-stage aging voltage which is varied in the order opposite to each other to the adjacent scan line. The method of claim 1, The aging period is And a neutralizing step of applying the same aging voltage to the adjacent scan line. The method of claim 1, In the aging period And a multi-stage aging voltage is applied to the scan line so as to sequentially increase or decrease the voltage difference between the odd scan line and the even scan line. The method of claim 1, In the aging period And a multi-stage aging voltage is applied to the scan line so that the voltage difference between the odd scan line and the even scan line sequentially increases and decreases or decreases and then increases. The method of claim 1, In the aging period An aging voltage in which the aging voltage varies in multiple steps to the odd scan line is applied to the even scan line in an order opposite to that of the odd scan line. The method of claim 1, In the aging period 10. A method of driving an EL display panel, wherein a multi-stage aging voltage that sequentially increases in one of the odd scan lines and the even scan lines is applied to a multi-stage aging voltage that sequentially decreases in the remaining scan lines. The method of claim 1, In the aging period A method of driving an EL display panel, characterized in that a multi-stage aging voltage that sequentially increases and decreases in one of the odd scan lines and the even scan lines is applied to the other scan lines. . The method of claim 1, In the aging period A multi-stage aging voltage that is sequentially increased or decreased sequentially is applied to any one of the odd scan line and the even scan line, and a constant voltage is applied to the remaining scan lines. The method of claim 1, In the aging period A multi-level aging voltage is sequentially applied to one of the odd scan line and the even scan line, and the first scan line and the even scan line are sequentially applied to the scan line. Driving method. The method according to any one of claims 9 and 10, The constant voltage applied in the aging period is the same voltage as the lowest aging voltage among the multi-stage aging voltages. The method according to any one of claims 9 and 10, And the constant voltage applied to the aging period is the same voltage as the scan low voltage supplied as an enable voltage to the scan line in the scan period. The method according to any one of claims 4 to 10, The aging period is And a neutralization step of applying the same aging voltage to the odd and even scan lines. The method of claim 13, In the neutralization step And the odd and even scan lines are equal to an intermediate voltage among the multi-level aging voltages. The method according to any one of claims 4 to 10, The multi-stage aging voltage is a multi-stage voltage between the highest aging voltage greater than or equal to the scan high voltage supplied to the scan line and the lowest aging voltage such as the scan low voltage supplied to the enable voltage in the scan period. And a voltage divided by. The method according to any one of claims 4 to 10, And a multi-stage aging voltage is repeated within the aging period. The method of claim 1, And the scanning period and the aging period are repeated for each frame. A data driver for plotting a data signal on the data line in the scan period and the data line in the aging period; A scan driver for causing a scan pulse on a scan line in the scan period and a multi-step voltage difference between adjacent scan lines in the aging period; And an EL cell formed at each intersection of the scan line and the data line, the EL cell having an EL display panel that emits light according to the data signal in the scan period and self-ages in the aging period. An EL display panel drive device. The method of claim 18, The scan driver And a multi-stage aging voltage which is varied in the order opposite to each other to the adjacent scan lines in the aging period. The method of claim 18, The scan driver And a neutralizing step of applying the same aging voltage to the adjacent scan lines within the aging period. The method of claim 18, The scan driver And a multi-stage aging voltage which sequentially increases or decreases the voltage difference between the odd scan line and the even scan line to the scan line in the aging period. The method of claim 18, The scan driver And a multi-stage aging voltage is applied to the scan line in the aging period so that the voltage difference between the odd scan line and the even scan line increases and decreases or decreases and then increases. The method of claim 18, The scan driver And an aging voltage that is varied in multiple steps to the odd scan line in the aging period, and an aging voltage that is varied in the order opposite to the odd scan line to the even scan line. The method of claim 18, The scan driver A multi-stage aging voltage that is sequentially increased to any one of an odd scan line and an even scan line in the aging period, and a multistage aging voltage that is sequentially reduced to the remaining scan lines is applied . The method of claim 18, The scan driver An EL display characterized by applying a multi-stage aging voltage that sequentially increases and decreases to any one of the odd scan line and the even scan line in the aging period, and then increases and decreases the multi-stage aging voltage to the other scan lines sequentially The drive unit of the panel. The method of claim 18, The scan driver And applying a multi-stage aging voltage that sequentially increases or decreases to any one of the odd scan line and the even scan line in the aging period, and applies a constant voltage to the remaining scan lines. The method of claim 18, The scan driver In the aging period, a multi-stage aging voltage is sequentially applied to one of the odd scan lines and the even scan lines, and then decreased or sequentially decreased, and a constant voltage is applied to the remaining scan lines. Driving device of EL display panel. 28. The method of any of claims 26 and 27, And the constant voltage applied in the aging period is the same voltage as the lowest aging voltage among the multi-stage aging voltages. 28. The method of any of claims 26 and 27, And the constant voltage applied to the aging period is the same voltage as the scan low voltage supplied as an enable voltage to the scan line in the scan period. The method according to any one of claims 21 to 27, The scan driver And a neutralization step of applying the same aging voltage to the odd and even scan lines within the aging period. The method of claim 30, The scan driver And the same intermediate voltage among the multi-stage aging voltages is applied to the odd and even scan lines in the neutralizing step. The method according to any one of claims 21 to 27, The scan driver In the scan period, the voltage between the highest aging voltage that is greater than or equal to the scan high voltage supplied to the scan line and the lowest aging voltage such as the scan low voltage supplied to the enable voltage is divided into multiple steps. A drive device for an EL display panel, which is supplied at an aging voltage. The method according to any one of claims 21 to 27, The scan driver And the multi-stage aging voltage is repeatedly supplied within the aging period. The method of claim 18, The scan driver And the scan period and the aging period are repeated for each frame. The method of claim 18, The scan driver A shift register having a plurality of stages for shifting the start pulses to supply the respective output signals and the next stage start pulses, and a plurality of dummy stages for shifting the output signals of the last stage of the stages to secure the aging period; ; Level shifting each of the output signals of the shift register to supply the scan pulse to the scan line in the scan period, and a plurality of levels for supplying the multilevel aging voltage to have the multistep voltage difference to the adjacent scan line in the aging period. And a level shifter portion having a shifter. The method of claim 18, The scan driver A shift register having a plurality of stages for shifting the start pulses and supplying the respective output signals and the next stage start pulses; Level shifting each of the output signals of the shift register to supply the scan pulse to the scan line in the scan period, and to supply the multi-level aging voltage to have the multi-step voltage difference to the adjacent scan line in the aging period in the aging period. And a level shifter portion having a plurality of level shifters. The method of claim 36, And a start pulse of a next frame is delayed and supplied so that the aging period can be included after the scan period. The method according to any one of claims 17 and 18, Each of the plurality of stages supplies an enable signal corresponding to the shifted start pulse, The level shifter part And the multi-level aging voltage is varied in synchronization with the aging period in a period in which the enable signal is output in each of the dummy stages.

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