KR102304599B1 - Organic light emmiting diode display device and driving method of the same - Google Patents

Abstract

The present invention discloses an organic light emitting display device. More particularly, the present invention relates to an organic light emitting display device in which an afterimage phenomenon is improved through direct sensing of device characteristics in a current driving type organic light emitting display device to determine the degree of deterioration, and to a driving method thereof.
According to an embodiment of the present invention, by fixing the voltage level of the gate terminal of the driving transistor and controlling the voltage of the source terminal through the data line to perform the image display step and the sensing step, the degree of deterioration of the driving transistor and the organic light emitting diode It has the effect of removing afterimages by directly sensing and realizing high-quality images.

Description

Organic light emitting display device and driving method thereof

The present invention relates to an organic light emitting display device, and an organic light emitting display device in which an afterimage phenomenon is improved through direct sensing of device characteristics in a current driving type organic light emitting display device to determine the degree of deterioration, and a method for driving the same is about

As a flat panel display to replace the existing cathode ray tube display, liquid crystal display, field emission display, plasma display panel ) and an organic light-emitting diode display (OLED display).

Among them, the organic light emitting diode provided in the organic light emitting display device has high luminance and low operating voltage characteristics, and since it is a self-luminous type that emits light by itself, the contrast ratio is large and it is easy to implement an ultra-thin display. . In addition, it has the advantage of being easy to implement moving images with a response time of several microseconds (㎲), there is no limitation of the viewing angle, and is stable even at low temperatures.

The organic light emitting display device has a structure in which a driving transistor provided in a pixel controls the amount of current flowing through the organic light emitting diode to display the gray level of the image, and the degree of deterioration of the driving transistor and the organic light emitting diode determines the image quality. become an important factor in

However, unlike other elements such as a switching transistor provided in a pixel, the driving transistor is continuously applied with a DC voltage and deteriorates, resulting in a problem in that characteristics change.

In order to solve this problem, a structure for compensating the threshold voltage characteristic of the driving transistor inside or outside the panel has been proposed. Among them, the compensation method inside the panel has a disadvantage in that the pixel structure is complicated and the aperture ratio is lowered as a plurality of transistors are further provided in the pixel. An external compensation method of sensing the threshold voltage (Vth) and reflecting the result to the data voltage is widely used.

1 is a diagram showing an equivalent circuit diagram of one pixel of a conventional external compensation type organic light emitting display device.

As shown, the conventional organic light emitting display device includes a display panel in which a plurality of pixels PX are defined, and the display panel includes first and second scan signals Vscan1 and Vscan2 and a data voltage Vdata. and wirings SL1 , SL2 , DL and RL to which the reference voltage Vref is input are formed to cross each other, and one pixel PX is defined at the intersection point.

In addition, the pixel PX includes the organic light emitting diode OLED to which the ground voltage ELVSS is applied to one terminal, and the data voltage Vdata in response to the first scan signal Vscan1 to the first node N1. The first switching transistor STFT1 to be applied, the second switching transistor STFT2 to apply the reference voltage Vref to the second node N2 in response to the second scan signal Vscan2, and a driving voltage to one terminal (ELVDD) is applied, the driving transistor DTFT applying a drain-source current to the organic light emitting diode OLED according to the voltage applied to the first node N1, and the gate electrode of the driving transistor DTFT It includes a first capacitor C1 that maintains the applied voltage for one frame, and a second capacitor C2 connected to the reference line RL and charged with a voltage corresponding to a current flowing through the driving transistor DTFT.

However, the conventional organic light emitting display device has a structure in which the reference line RL for sensing is shared between adjacent sub-pixels in order to increase the aperture ratio of the pixels PX and reduce the channel of the data driver. Accordingly, all sensing currents of each sub-pixel flow to the organic light-emitting diode OLED having the lowest threshold voltage Vth, making it difficult to sense the current flowing through the organic light-emitting diode for each sub-pixel.

In addition, as the current is set to flow through the organic light emitting diode (OLED) during the sensory period, a noise image irrelevant to the image is displayed, which causes the low marketability of the organic light emitting diode display.

In addition, as the reference line for supplying the reference voltage Vref and the second scan line SL2 for controlling the signal applied thereto are formed, the aperture ratio decreases.

Therefore, in the conventional organic light emitting display device having a structure in which a reference line is shared between sub-pixels, it is difficult to generate accurate deterioration compensation data because the currents of the driving transistor (DTFT) and the organic light-emitting diode (OLED) cannot be sensed in units of sub-pixels. , there was a limit to realizing high-quality images.

The present invention has been devised to solve the above-described problems, and the present invention directly senses the characteristics of a driving transistor and an organic light emitting diode for each sub-pixel to generate compensation data, thereby removing an afterimage and implementing an organic electric field of high quality. An object of the present invention is to provide a light emitting display device.

In order to achieve the above object, an organic light emitting display device according to a preferred embodiment of the present invention includes a display panel in which a plurality of scan wirings and data wirings are intersected, and a plurality of pixels are provided at the intersections; and a scan driver for conducting the pixel, and a data driver for supplying a sensing voltage or a data voltage corresponding to image data to the pixel through the data line.

In particular, the organic light emitting display device of the present invention is characterized in that it senses and compensates the threshold voltages of the driving transistor and the organic light emitting diode in real time using an external compensation method. A sensing unit for outputting sensed sensing data, a compensation processing unit for accumulating and storing the sensing data output from the sensing unit in pre-stored sensing data, and generating compensation data in response to the accumulated sensing data; and a timing controller that controls the data driver and reflects the compensation data to the image data.

In addition, in order to achieve the above object, in the method of driving an organic light emitting display device according to a preferred embodiment of the present invention, a sensing voltage or a data voltage corresponding to image data is supplied to the pixel through a data line to the pixel. Outputs sensing data sensing the device characteristics of , and accumulates and stores the sensing data output from the sensing unit in pre-stored sensing data. Thereafter, compensation data is generated in response to the accumulated sensing data and reflected in the image data, so that real-time compensation for each sub-pixel can be implemented without a separate light emission period.

Here, the step of outputting the sensed data may be subdivided into a writing step, an emission step, a sensing step, and a recovery step.

According to the organic light emitting display device and the driving method thereof according to an embodiment of the present invention, the image display step and the sensing step are performed by fixing the voltage level of the gate terminal of the driving transistor and controlling the voltage of the source terminal through the data line. By doing so, there is an effect of directly sensing the degree of deterioration of the driving transistor and the organic light emitting diode to remove an afterimage and realizing a high-quality image.

1 is a diagram showing an equivalent circuit diagram of one pixel of a conventional external compensation type organic light emitting display device.
2 is a view showing the overall structure of an organic light emitting display device according to an embodiment of the present invention.
3 is a diagram illustrating a connection structure between the sensing unit 130 and the pixel PX of the organic light emitting display device according to an embodiment of the present invention.
4 is an equivalent circuit diagram illustrating the structure of one pixel of an organic light emitting display device according to an embodiment of the present invention.
FIG. 5 is a diagram illustrating a signal waveform applied to the pixel of FIG. 4 .
6 is a diagram illustrating a structure of a compensation processing unit of an organic light emitting display device according to an embodiment of the present invention.
7 is a diagram schematically illustrating a threshold voltage (Vth) distribution of sending data processed by the compensation processing unit of FIG. 6 .

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention belongs It is provided to fully inform the possessor of the scope of the invention, and the present invention is only defined by the scope of the claims.

When 'to include', 'includes', 'have', 'consists of', etc. mentioned in this specification are used, other parts may be added unless 'only' is used. When a component is expressed in the singular, the case in which the plural is included is included unless otherwise explicitly stated.

In interpreting the components, it is interpreted as including an error range even if there is no separate explicit description.

In the case of a description of a temporal relationship, for example, when a temporal relationship is described as 'after', 'following', 'after', 'before', etc., 'immediately' or 'directly' Unless ' is used, cases that are not continuous may be included.

Although the first, second, etc. are used to describe various components, these components are not limited by these terms. These terms are only used to distinguish one component from another. Accordingly, the first component mentioned below may be the second component within the spirit of the present invention.

Each feature of the various embodiments of the present invention may be partially or wholly combined or combined with each other, technically various interlocking and driving are possible, and each embodiment may be implemented independently of each other or may be implemented together in a related relationship. may be

Hereinafter, an organic light emitting display device and a driving method thereof according to a preferred embodiment of the present invention will be described with reference to the drawings.

2 is a view showing the overall structure of an organic light emitting display device according to an embodiment of the present invention.

Referring to FIG. 2 , in the organic light emitting display device of the present invention, a plurality of scan lines SL and data lines DL are intersected, and the display panel includes a plurality of pixels PX provided at the intersection points. (100), the scan driver 110 for conducting the pixel PX, the sensing voltage Vsen to the pixel PX through the data line DL, or a data voltage corresponding to the image data RGB′ A data driving unit 120 for supplying (Vdata), a sensing unit for outputting sensing data (SS_data[n], n is a natural number) sensing the device characteristics of the pixel PX in response to the sensing voltage Vsen ( 130), a compensation processing unit 140 that accumulates and stores the sensing data SS_data[n] output from the sensing unit 130 in pre-stored sensing data, and generates compensation data in response to the accumulated sensing data; and the and a timing controller 150 that controls the scan driver 110 and the data driver 120 and reflects the compensation data to the image data RGB'.

In the display panel 100 , a plurality of scan lines SL and data lines DL are formed to cross each other on a glass substrate or a plastic substrate, and at the intersections of the scan lines SL and the data lines DL, respectively. A plurality of pixels PX corresponding to red, green, blue, and white are formed.

The plurality of pixels PX includes a plurality of thin film transistors, organic light emitting diodes, and capacitors, and although not shown, various wirings for supplying the power supply voltage ELVDD and the ground voltage ELVSS formed in the display panel 100 . is connected with

Here, the plurality of thin film transistors include first and second switching transistors connected to the scan line SL, and a driving transistor connected to the data line DL, and the capacitor is disposed between the gate terminal and the source terminal of the driving transistor. Connected. In addition, the organic light emitting diode may include a first electrode (hole injection electrode), an organic compound layer, and a second electrode (electron injection electrode). A detailed structure and description of the pixel PX will be described later.

The scan driver 110 applies the scan signal Vscan to each pixel PX in units of one horizontal line in response to the scan control signal SCS from the timing controller 150 . The scan driver 110 may include a conventional shift register.

The data driver 120 receives the image data RGB of a digital waveform applied from the timing controller 150 and converts it to a data voltage Vdata in the form of an analog voltage that corresponds to the grayscale value of the image and is input to the pixel PX. converted, and the data voltage Vdata is applied to each pixel PX through the data line DL in response to the input data control signal DCS.

The sensing unit 130 senses the device characteristics of the driving transistor of the pixel and the organic light emitting diode in real time in a blank time between each frame during driving of the organic light emitting display device, and the sensing data is compensated by the compensation processing unit 140 . forward to

Here, the device characteristics sensed by the sensing unit 130 include the threshold voltage Vth of the driving transistor and the organic light emitting diode. Conventionally, in order to apply the external compensation method, the threshold voltages of the driving transistor and the organic light emitting diode are sensed by using a separate second scan line (SL2 in FIG. 2) and a reference line (RL in FIG. 2). In the example, the wirings are omitted, the data voltage Vdata is applied through one scan line, and the driving current is sensed.

The sensing data SS_data[n] by the sensing unit 130 is generated in real time while the organic light emitting display device is driven, and the sensing process is performed in a blank section between each frame of the image, and each time the compensation processing unit 140 is generated. transmitted and updated.

The compensation processing unit 140 receives the sensing data SS_data[n] for the threshold voltage Vth of the driving transistor and the organic light emitting diode from the sensing unit 130 and generates compensation data. Here, the sensing data SS_data[n] is stored in the form of being accumulated in the sensing data set in the initial stage of driving of the organic light emitting display device or the previously generated sensing data SS_data[n-1], and is stored in a lookup table (LUT). is converted into reward data.

As illustrated in the figure, the compensation processing unit 140 and the sensing unit 130 may be embedded as circuit logic in the timing control unit 150 and the data driving unit 120, respectively, or may be implemented as separate ICs.

The timing controller 150 receives timing signals such as a clock signal and vertical and horizontal synchronization signals applied from an external system (not shown) and generates control signals such as a scan control signal (SCS) and a data control signal (DCS). The role of controlling each driver, and applying compensation data to the image data (RGB) to improve the problem of image quality degradation due to deterioration of the driving transistor and the organic light emitting diode, and to convert the image data (RGB) to the data driver 120 Sort and output in a form that can be processed.

According to this structure, the organic light emitting display device of the present invention senses the threshold voltage (Vth) of the driving transistor and the organic light emitting diode in real time through the data wiring and generates compensation data in response thereto, thereby realizing a high aperture ratio and real time Thus, there is an effect of compensating for deterioration of the driving transistor and the organic light emitting diode.

Hereinafter, a sensing unit of an organic light emitting display device according to an embodiment of the present invention and a pixel connection structure thereof will be described with reference to the drawings.

3 is a diagram illustrating a connection structure between the sensing unit 130 and the pixel PX of the organic light emitting display device according to an embodiment of the present invention.

Referring to FIG. 3 , the sensing unit 130 of the present invention includes a first converter DAC for supplying a sensing voltage Vsen and a second converter ADC for outputting sensing data SS_data[n], and a latch unit 132 respectively connected to the first and second converters ADC and DAC, and a switch unit 134 selectively connecting the latch unit 132 and the data line DL.

In addition, in the pixel PX on the display panel, one data line DL is connected to each of the sub-pixels P1 to P4 corresponding to red, green, blue, and white, and the data line DL is connected to the switch unit ( 134), one for each of the first and second switches sw1 and sw2 is connected. In addition, one scan line SL and power lines PL1 and PL2 supplying a power supply voltage ELVDD and a ground voltage ELVSS are connected to each of the pixels P1 to P4 .

The first converter (DAC) is a digital-to-analog converter, and is connected to a compensation processing unit (not shown) to receive a sensing control signal (SEN) of a digital waveform and convert it to a sensing voltage (Vsen), which is an analog waveform. convert The converted sensing voltage Vsen is transmitted to the latch unit 132 .

The second converter ADC is an analog-to-digital converter, and converts the driving current Ids flowing through the data line DL into sensing data SS_data[n] of a digital waveform. The converted sensing data SS_data[n] is transmitted to the compensation processing unit.

The latch unit 132 may include first and second latches 1321 and 1322 respectively connected to the first converter DAC and the second converter ADC, and the first latch 1321 is the converted The sensing voltage Vsen is latched and outputted through the data line DL in units of one horizontal line. Also, the second latch 1322 latches the sensed driving current Ids and transfers it to the second converter ADC in units of one horizontal line.

The switching unit 134 includes first and second switches sw1 and sw2 provided between the latch unit 132 and the data line DL. First and second switches sw1 and sw2, that is, two switches are allocated to one data line DL.

The first switch sw1 connects the first latch 1321 and the data line DL to transfer the output of the first latch 1321 to the data line DL, and the second switch sw2 connects the second latch 132 and the data line DL are connected to transmit the driving current Ids to the second latch 132 .

According to this structure, the sensing process of the driving current Ids can be performed through the data lines connected to each sub-pixel P1 to P4, so that a pixel structure having a high aperture ratio can be implemented without increasing signal lines.

Hereinafter, a pixel structure of an organic light emitting display device according to an embodiment of the present invention and a driving method thereof will be described with reference to the drawings.

4 is an equivalent circuit diagram illustrating the structure of one pixel of an organic light emitting display device according to an embodiment of the present invention, and FIG. 5 is a diagram illustrating a signal waveform applied to the pixel of FIG. 4 .

4, in one pixel PX of the organic light emitting display device of the present invention, a gate terminal is connected to the scan line SL, a reference voltage Vref is applied to a drain terminal, and a source terminal is first A first switching transistor STFT1 connected to the first node N1, a gate terminal is connected to the scan line SL, a drain terminal is connected to the data line DL, and a source terminal is connected to a second node N2. a second switching transistor STFT2 connected to , a gate terminal connected to the first node N2, a power supply voltage ELVDD is applied to a drain terminal, and a source terminal connected to the second node N2 A transistor DTFT, a capacitor C1 connected between the first and second nodes N1 and N2, an anode terminal connected to the second node N2, and a ground voltage ELVSS connected to a cathode terminal and an applied organic light emitting diode (OLED).

When the driving method of the organic light emitting display device having the pixel PX having such a structure will be described with reference to FIGS. 4 and 5 together, the driving method of the organic light emitting display device of the present invention includes a writing step and an emission step. It is divided into (Emission), a sensing step (sensing) and a recovery step (Recovery) step.

The writing step (①) turns on the first and second switching transistors STFT1 and STFT2 to charge the reference voltage Vref and the data voltage Vdata to the gate terminal and the source terminal of the driving transistor DTFT. is a step

In the emitting step (②), the first and second switching transistors STFT1 and STFT2 are turned off to emit light from the organic light emitting diode OLED by the driving current Ids according to the gate and source terminal voltage Vgs. It is a step to

In the sensing step (③), the first and second switching transistors STFT1 and STFT2 are turned on, the driving current is sensed through a sensing voltage Vsen, and the first and second switching transistors STFT1 and STFT2 are turned on. STFT2) is the turn-off step.

The recovery step (④) is a step of increasing the voltage level of the gate terminal by turning on the first and second switching transistors STFT1 and STFT2.

Each step will be described in detail, in the writing step (①), first, the first switch SW of the sensing unit is turned on so that the data voltage Vdata of the voltage level Vn for grayscale expression is converted to the first converter DAC. is output from and as a high-level scan signal Vscan is applied, the first switching transistor STFT1 is turned on to charge the first node N1 with the reference voltage Vref, and the second switching transistor STFT1 is turned on. STFT2) is turned on and the second node N2 is charged with the data voltage Vdata.

At this time, since the second node N2 is connected to the cathode terminal of the organic light emitting diode OLED, the voltage level charged in the second node N2 is the data voltage Vdata to the threshold voltage of the organic light emitting diode Vth. is the voltage (Vk) minus .

Next, in the discharging step (②), both the first and second switches sw1 and sw2 are turned off, and as the low-level scan signal Vscan is applied, the first node N1 is floating ) state. Also, since the voltage charged in the first and second nodes N1 and N2 is the gate-source voltage Vgs of the driving transistor DTFT, the driving transistor DTFT is turned on to obtain the gate-source voltage Vgs. A driving current Ids corresponding to .

Accordingly, the driving current Ids flows to the organic light emitting diode OLED to emit light. In addition, the voltage level of the second node N2 is increased from the voltage level of Vk to Vgs - Vth obtained by subtracting the threshold voltage Vth from the gate-source voltage Vgs of the driving transistor DTFT. In addition, the first node N1 also has the same rising width as the second node N2 and the voltage level is increased by the capacitor C1.

Accordingly, the voltage Vs charged in the second node N2 includes both the threshold voltage components of the driving transistor DTFT and the organic light emitting diode OLED. In particular, in this emission step, a process for sensing the threshold voltage characteristic of the organic light emitting diode (OLED) proceeds together, so that a separate light emission period for sensing is not required.

In addition, the data line DL is in a state of being charged with the data voltage Vdata, and in order to enter the sensing stage thereafter, the voltage level of the data voltage Vdata after a predetermined period is the initialization voltage Vinit and the sensing voltage Vsen. ) is transitioned to

Subsequently, in the sensing step (③), the second switch sw2 is turned on, and as the scan signal Vscan transitions to a high level, the first and second switching transistors STFT1 and STFT2 are turned on to turn on the driving current ( Ids) flows through the second converter ADC, and at this time, the voltage Vs charged in the second node N2 is converted into sensing data and output, so that the threshold voltage Vth is sensed.

Next, in the recovery step (④), the first switch sw1 is turned on and the second switch sw2 is turned off to recharge the first node N1 to the data voltage Vdata level. In this case, as the first switching transistor STFT1 is turned on in the sensing step, the first node N1 is discharged to the reference voltage Vref level to shorten the charging time of the data voltage Vdata in a subsequent frame. it is for

Since the sensing step and the recovery step (③, ④) are real-time driving, the vertical synchronization signal Vsync is performed in a blank time.

According to the pixel structure and driving method, the driving method of the organic light emitting display device of the present invention can sense and compensate the driving transistor (DTFT) and the organic light emitting diode (OELD) in real time while the display device is being driven.

In particular, as the sensing period is completed within the blank period, a separate light emission period is not required, and thus an unnecessary noise image is not displayed.

Hereinafter, the structure of the compensation processing unit of the organic light emitting display device according to a preferred embodiment of the present invention will be described with reference to the drawings.

6 is a diagram showing the structure of a compensation processing unit of an organic light emitting display device according to an embodiment of the present invention, and FIG. 7 is a schematic diagram illustrating the distribution of the threshold voltage (Vth) of sending data processed by the compensation processing unit of FIG. 6 . It is a drawing.

Referring to FIG. 6 , the compensation processing unit 140 of the organic light emitting display device of the present invention includes a sensing control unit 141 that controls the sensing unit 130 , and the sensing data SS_data[ n]) is accumulated and stored, the LUT 145 in which a compensation value corresponding to the sensing data SS_data[n] is stored, and the sensing data stored in the memory unit 143 is read, and the LUT ( 145) and includes a compensation data generator 146 that generates compensation data CPS_data corresponding to the read sensed data.

The sensing control unit 141 controls the sensing unit 130 to generate sensing data from a pixel, and transmits the sensing control signal SEN. The sensing control signal SEN is a signal of a digital waveform, and may be converted into a sensing voltage of an analog waveform in a sensing step when the organic light emitting display device is driven and applied to the pixel.

The memory unit 143 stores sensing data or updated sensing data with respect to the threshold voltage Vth of a preset pixel at the initial driving stage. In detail, in the memory unit 143 , the distribution of the threshold voltage Vth according to the deterioration of each pixel (P1 to Pn, n is a natural number) according to an experimental value is stored in the initial driving period of the organic light emitting display device, and thereafter The sensing data (SS_data[1] to SS_data[n]) input according to the driving of the display device is accumulated and stored.

The reason for accumulating the sensing data (SS_data[n]) is that when a black grayscale, that is, a region where the organic light emitting diode is not turned on, is included in the image for every frame, the threshold voltage Vth is not sensed for that part. Because it needs to be improved.

The LUT 145 stores a driving transistor for each sub-pixel and a compensation value of the driving transistor according to the threshold voltage Vth of the organic light emitting diode.

The compensation data generation unit 146 reads the most recently updated sensing data stored in the memory unit 143 and generates compensation data CPS_data with reference to the LUT 145 . The compensation data CPS_data is reflected in the image data by a timing controller (not shown) and provided to the data driver.

Although many matters are specifically described in the foregoing description, these should be construed as examples of preferred embodiments rather than limiting the scope of the invention. Accordingly, the invention should not be defined by the described embodiments, but should be defined by the claims and equivalents to the claims.

100: display panel 110: scan driver
120: data driving unit 130: sensing unit
140: compensation processing unit 150: timing control unit
PX: Pixel SL: Scan wiring
DL: data wiring Vdata: data voltage
Vscan : scan signal Vref : reference voltage
SCS : Scan control signal DCS : Data control signal
RGB: Image data SS_data[n]: Sensing data
SEN: sensing control signal Vsen: sensing voltage

Claims (9)

A display panel comprising: a display panel in which a plurality of scan wirings and data wirings are intersected, the display panel having a plurality of pixels provided at intersections;
a scan driver for conducting the pixel;
a data driver supplying a sensing voltage or a data voltage corresponding to image data to the pixel through the data line;
a sensing unit connected to the data line and outputting sensing data sensing device characteristics of the pixel in response to the sensing voltage;
a compensation processing unit for accumulating and storing the sensing data output from the sensing unit in pre-stored sensing data, and generating compensation data in response to the accumulated sensing data; and
a timing controller for controlling the scan driver and the data driver, and reflecting the compensation data to the image data;
The pixel is
a first switching transistor to which a reference voltage is applied to a drain terminal and a source terminal is connected to a first node;
a second switching transistor having a drain terminal connected to the data line and a source terminal connected to a second node;
a driving transistor having a gate terminal connected to a first node and a source terminal connected to the second node; and
and an organic light emitting diode connected to the second node and emitting light by a driving current from the driving transistor,
and the driving current is output to the sensing unit through the second node and the second switching transistor. The method of claim 1,
The sensing unit,
a first converter for supplying the sensing voltage;
a second converter for outputting the sensed data;
a latch unit connected to the first and second converters; and
a switch part selectively connecting the latch part and the data line
An organic light emitting display device comprising a. The method of claim 1,
The pixel further includes a capacitor connected between the first and second nodes,
a gate terminal of the first switching transistor and a gate terminal of the second switching transistor are connected to the scan line;
A power supply voltage is applied to the drain terminal of the driving transistor,
The organic light emitting diode display device, wherein an anode terminal is connected to the second node and a ground voltage is applied to a cathode terminal of the organic light emitting diode. The method of claim 1,
The compensation processing unit,
a sensing control unit for controlling the sensing unit;
a memory unit for accumulating and storing the sensing data output from the sensing unit;
a LUT in which a compensation value corresponding to the sensing data is stored; and
A compensation data generation unit that reads the sensing data stored in the memory unit and generates compensation data corresponding to the read sensing data with reference to the LUT
An organic light emitting display device comprising a. supplying a sensing voltage or a data voltage corresponding to image data to a pixel through a data line to output sensing data sensed by a driving current from a driving transistor of the pixel;
accumulating and storing the sensing data in pre-stored sensing data;
generating compensation data in response to the accumulated sensing data; and
and reflecting the compensation data to the image data,
The step of outputting the sensing data comprises:
The first switching transistor of the pixel is turned on to charge a reference voltage to the gate terminal and the first node of the driving transistor, and the second switching transistor of the pixel is turned on to turn on the source terminal and the second node of the driving transistor. a writing step of charging the data voltage to a node;
an emission step of turning off the first switching transistor and the second switching transistor to output the driving current according to the voltages of the gate terminal and the source terminal of the driving transistor to the organic light emitting diode of the second node and the pixel; and
and a sensing step of turning on the first switching transistor and the second switching transistor to sense the driving current through the second switching transistor and the data line. 6. The method of claim 5,
The step of outputting the sensed data further includes a recovery step of increasing the voltage level of the gate terminal by turning on the first and second switching transistors after the sensing step,
The sensing step may further include turning off the first switching transistor and the second switching transistor after sensing the driving current. 7. The method of claim 6,
The writing step is
As the anode of the organic light emitting diode is connected to the source terminal and the second node of the driving transistor, the voltage charged to the source terminal and the second node of the driving transistor is the data voltage and the threshold voltage component of the organic light emitting diode A driving method of an organic light emitting display device, characterized in that the voltage is included. 7. The method of claim 6,
The release step is
applying the data voltage and after a predetermined time elapses, applying an initialization voltage to the data line; and
applying the sensing voltage to the data line
A method of driving an organic light emitting display device, characterized in that it further comprises. 7. The method of claim 6,
The sensing step and the recovery step,
A method of driving an organic light emitting display device, characterized in that it is performed in a blank section between each frame of an image.

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