KR20090131786A - Organic light emitting display and driving method thereof - Google Patents

Abstract

PURPOSE: An organic electroluminescent display device and a driving method thereof are provided to compensate for deterioration of an organic light emitting diode by generating the second data to generate the light with uniform brightness in all pixels from the first data and the deterioration information. CONSTITUTION: A data driver(120) supplies data signals generated using the second data supplied from a timing controller for a display period to data lines. A sensing unit measures the deterioration information of an organic light emitting diode included in the pixels. A switching unit connects one of the sensing unit and the data driving unit with the data lines. A timing controller(150) stores the deterioration information in the memory, controls the power unit using the deterioration information, and generates the second data using the deterioration information and the first data supplied from the outside. A power unit(190) controls the voltage values of the first power or second power corresponding to the control of the timing controller.

Description

Organic Light Emitting Display and Driving Method Thereof

The present invention relates to an organic light emitting display device and a driving method thereof, and more particularly, to an organic light emitting display device and a driving method thereof capable of compensating for degradation of an organic light emitting diode.

Recently, various flat panel displays have been developed to reduce weight and volume, which are disadvantages of cathode ray tubes. The flat panel display includes a liquid crystal display, a field emission display, a plasma display panel, and an organic light emitting display.

Among flat panel displays, an organic light emitting display device displays an image using organic light emitting diodes (OLEDs) that generate light by recombination of electrons and holes. Such an organic light emitting display device has an advantage of having a fast response speed and being driven with low power consumption.

1 is a circuit diagram illustrating a pixel of a conventional organic light emitting display device.

Referring to FIG. 1, a pixel 4 of a conventional organic light emitting display device is connected to an organic light emitting diode OLED, a data line Dm, and a scanning line Sn to control the organic light emitting diode OLED. The pixel circuit 2 is provided.

The anode electrode of the organic light emitting diode OLED is connected to the pixel circuit 2, and the cathode electrode is connected to the second power source ELVSS. Such an organic light emitting diode (OLED) generates light having a predetermined brightness in response to a current supplied from the pixel circuit 2.

The pixel circuit 2 controls the amount of current supplied to the organic light emitting diode OLED corresponding to the data signal supplied to the data line Dm when the scan signal is supplied to the scan line Sn. To this end, the pixel circuit 2 includes a second transistor M2 connected between the first power supply ELVDD and the organic light emitting diode OLED, the second transistor M2, the data line Dm, and the scan line Sn. And a storage capacitor C connected between the gate electrode and the first electrode of the second transistor M2.

The gate electrode of the first transistor M1 is connected to the scan line Sn, and the first electrode is connected to the data line Dm. The second electrode of the first transistor M1 is connected to one terminal of the storage capacitor C. Here, the first electrode is set to any one of a source electrode and a drain electrode, and the second electrode is set to an electrode different from the first electrode. For example, when the first electrode is set as the source electrode, the second electrode is set as the drain electrode. The first transistor M1 connected to the scan line Sn and the data line Dm is turned on when a scan signal is supplied from the scan line Sn to receive a data signal supplied from the data line Dm, and the storage capacitor C ). In this case, the storage capacitor C charges a voltage corresponding to the data signal.

The gate electrode of the second transistor M2 is connected to one terminal of the storage capacitor C, and the first electrode is connected to the other terminal of the storage capacitor C and the first power supply ELVDD. The second electrode of the second transistor M2 is connected to the anode electrode of the organic light emitting diode OLED. The second transistor M2 controls the amount of current supplied from the first power source ELVDD to the second power source ELVSS via the organic light emitting diode OLED in response to the voltage value stored in the storage capacitor C. . In this case, the organic light emitting diode OLED generates light corresponding to the amount of current supplied from the second transistor M2.

In fact, the pixel 4 of the conventional organic light emitting display displays an image having a predetermined brightness while repeating the above-described process. On the other hand, in the digital driving in which the second transistor M2 operates as a switch, the first power source ELVDD and the second power source ELVSS are supplied to the organic light emitting diode OLED as it is, whereby the organic light emitting diode OLED is Light is emitted by constant voltage driving. As described above, in the digital driving method, a current is sensitively changed due to an increase in resistance due to deterioration of the organic light emitting diode (OLED), thereby causing a problem in that an image of a desired brightness cannot be displayed.

In detail, the organic light emitting diode OLED deteriorates with time. When the organic light emitting diode (OLED) is deteriorated, the resistance of the organic light emitting diode (OLED) increases, and accordingly, the current flowing to the organic light emitting diode (OLED) decreases in response to the same voltage, thereby lowering luminance.

Accordingly, it is an object of the present invention to provide an organic light emitting display device and a driving method thereof capable of compensating for degradation of an organic light emitting diode.

In an embodiment of the present invention, an organic light emitting display device includes pixels positioned at an intersection of data lines, scan lines, and control lines; The scan signal is sequentially supplied to the scan lines during the measurement period and the control signal is sequentially supplied to the control lines, and the scan lines are scanned between the respective syringes of each of the plurality of subfields included in one frame during the display period. A scan driver for sequentially supplying signals; A data driver supplying data signals generated using second data supplied from a timing controller to the data lines during the display period; A sensing unit for measuring degradation information of the organic light emitting diode included in each of the pixels; A switching unit for connecting any one of the sensing unit and the data driver to the data lines; A memory for storing the deterioration information; A timing controller which stores the deterioration information in the memory, controls a power supply unit using the deterioration information, and generates second data using the deterioration information and first data supplied from the outside; And a power supply unit for adjusting a voltage value of the first power supply or the second power supply in response to the control of the timing controller.

According to an embodiment of the present invention, a frame is divided into a plurality of subfields, and the method of driving an organic light emitting display device including pixels for controlling an amount of current flowing from a first power source to a second power source via an organic light emitting diode. Setting the voltage of the first power supply to be lower than the voltage of the second power supply during the characteristic recovery period, supplying a first current to the organic light emitting diode included in each of the pixels during the measurement period, and supplying the first current to the first current. Changing a correspondingly generated first voltage to a first digital value, setting a voltage of the first power supply to be higher than a voltage of the second power supply during a display period, and a maximum of the measured first voltages Before the deterioration of the voltage value and the organic light emitting diode deteriorates the voltage of the first power supply by the difference voltage between the reference voltage applied corresponding to the first current To raise the or the first using the first data; and supplied from the outside to 2 lower the voltage of the power generating second data, and generating a data signal using the second data.

According to the organic light emitting display device and the driving method thereof, the second data is generated such that light of uniform luminance is generated in all pixels from the degradation information and the first data while controlling the voltage of the first power source or the second power source. Degradation of the organic light emitting diode can be compensated for by generating

Hereinafter, the present invention will be described in detail with reference to FIGS. 2 to 10 with reference to the accompanying preferred embodiments in which those skilled in the art can easily practice the present invention.

2 is a diagram illustrating an organic light emitting display device according to an exemplary embodiment of the present invention.

Referring to FIG. 2, an organic light emitting display device according to an exemplary embodiment of the present invention includes pixels 140 connected to scan lines S1 to Sn, control lines CL1 to CLn, and data lines D1 to Dm. The pixel unit 130 including the pixel, the scan driver 110 for driving the scan lines S1 to Sn and the control lines CL1 to CLn, and the data driver for driving the data lines D1 to Dm. 120 and a timing controller 150 for controlling the scan driver 110 and the data driver 120.

In addition, the organic light emitting display device according to an embodiment of the present invention, the sensing unit 180 for extracting deterioration information of the organic light emitting diode included in each of the pixels 140, the sensing unit 180 and the data driver ( A switching unit 170 for selectively connecting the 120 to the data lines D1 to Dm, a memory 160 for storing information sensed by the sensing unit 180, a first power supply ELVDD, and a second power source; The apparatus further includes a power supply unit 190 for generating a power supply ELVSS.

The pixel unit 130 includes pixels 140 positioned at intersections of the scan lines S1 to Sn, the control lines CL1 to CLn, and the data lines D1 to Dm. The pixels 140 receive a first power source ELVDD and a second power source ELVSS from the power source 190. The pixels 140 control the amount of current supplied from the first power source ELVDD to the second power source ELVSS via the organic light emitting diode in response to the data signal. Then, light of a predetermined luminance is generated in the organic light emitting diode.

The scan driver 110 sequentially supplies the scan signals to the scan lines S1 to Sn under the control of the timing controller 150 during the measurement period and the display period. In addition, the scan driver 110 sequentially supplies a control signal to the control lines CL1 to CLn during the measurement period.

The data driver 120 supplies data signals to the data lines D1 to Dm under the control of the timing controller 150.

The switching unit 170 selectively connects the sensing unit 180 and the data driver 120 to the data lines D1 to Dm. To this end, the switching unit 170 includes at least two switches connected to each of the data lines D1 to Dm (that is, for each channel).

The sensing unit 180 extracts degradation information of the organic light emitting diode included in each of the pixels 140, and supplies the extracted degradation information to the timing controller 150. To this end, the sensing unit 180 includes a sensing circuit connected to each of the data lines D1 to Dm (that is, for each channel). In the present invention, the switching unit 170 and the sensing unit 180 are illustrated independently for convenience of description, but may be included in the data driver 120 when designing a circuit.

The timing controller 150 controls the data driver 120 and the scan driver 110. During the measurement period, the timing controller 150 stores the deterioration information supplied from the sensing unit 180 in the memory 160. During the display period, the timing controller 150 generates the second data Data2 using the first data Data1 input from the outside and supplies the generated second data Data2 to the data driver 120. Here, the bit value of the second data Data2 is set so that an image of uniform luminance can be displayed.

The power supply unit 190 sets the voltage of the first power supply ELVDD to be lower than the voltage of the second power supply ELVSS during the measurement period, and sets the voltage of the first power supply ELVDD during the display period. Set it higher. In addition, the power supply unit 190 adjusts the voltage value of the first power supply ELVDD or the second power supply ELVSS to compensate for the degradation of the pixels under the control of the timing controller 150.

3 is a diagram illustrating an embodiment of one frame during a display period.

Referring to FIG. 3, one frame according to an embodiment of the present invention includes a plurality of subfields SF1 to SF8. Each of the plurality of subfields SF1 to SF8 is divided into a syringe interval and a light emission period.

During the syringe period, the scanning signals are sequentially supplied to the scanning lines S1 to Sn. When the scan signals are sequentially supplied, the pixels 140 are selected in units of horizontal lines. In this case, the data signal is supplied to the pixels 140 selected by the scan signal.

In the light emitting period, the pixels 140 emit or not emit light in response to the data signal supplied during the syringe period. The light emission period is set differently for each of the subfields SF1 to SF8. That is, in the present invention, a predetermined gray scale is expressed by adjusting the emission time of the pixels 140 during one frame period.

Meanwhile, one frame shown in FIG. 3 is an embodiment of the present invention, and the present invention is not limited thereto. In fact, the present invention can be driven by various types of digital driving methods currently known.

4 is a diagram illustrating an embodiment of a pixel illustrated in FIG. 2. In FIG. 4, pixels connected to the m-th data line Dm and the n-th scan line Sn are illustrated for convenience of description.

Referring to FIG. 4, a pixel 140 according to an exemplary embodiment of the present invention includes an organic light emitting diode (OLED), a pixel circuit 142 for supplying current to the organic light emitting diode (OLED), and an organic light emitting diode (OLED). And a third transistor M3 connected between the anode electrode and the data line Dm.

The anode electrode of the organic light emitting diode OLED is connected to the pixel circuit 142, and the cathode electrode is connected to the second power source ELVSS. The organic light emitting diode OLED generates light having a predetermined luminance in response to a current supplied from the pixel circuit 142.

The pixel circuit 142 receives a data signal from the data line Dm when the scan signal is supplied to the scan line Sn. The pixel circuit 142 receiving the data signal supplies a current corresponding to the data signal to the organic light emitting diode OLED. The pixel circuit 142 may be configured in various forms to supply a current corresponding to the data signal to the OLED. For example, various types of pixels applied to currently known digital driving may be applied.

The third transistor M3 is connected between the anode electrode of the organic light emitting diode OLED and the data line Dm. The third transistor M3 is turned on when a control signal is supplied to the control line CLn.

FIG. 5 is a diagram illustrating an embodiment of the pixel circuit shown in FIG. 4.

Referring to FIG. 5, the pixel circuit 142 includes a first transistor M1, a second transistor M2, and a storage capacitor Cst.

The gate electrode of the first transistor M1 is connected to the scan line Sn, and the first electrode is connected to the data line Dm. The second electrode of the first transistor M1 is connected to the first terminal of the storage capacitor Cst. The first transistor M1 is turned on when the scan signal is supplied to the scan line Sn.

The gate electrode of the second transistor M2 is connected to the first terminal of the storage capacitor Cst, and the first electrode is connected to the second terminal of the storage capacitor Cst and the first power supply ELVDD. The second transistor M2 controls the amount of current flowing from the first power source ELVDD to the second power source ELVSS via the organic light emitting diode OLED in response to the voltage value stored in the storage capacitor Cst. In this case, the organic light emitting diode OLED generates light corresponding to the amount of current supplied from the second transistor M2.

The storage capacitor Cst charges a voltage corresponding to the data signal.

6 is a view illustrating in detail the switching unit and the sensing unit shown in FIG. In FIG. 6, a configuration connected to the m th data line Dm will be described for convenience of description.

Referring to FIG. 6, two switches SW1 and SW2 are provided in each channel of the switch unit 170. Each channel of the sensing unit 180 includes a sensing circuit 181 and an analog-to-digital converter (ADC) 182.

The first switch SW1 is positioned between the data driver 120 and the data line Dm. This first switch SW1 is turned on during the display period. In other words, the first switch SW1 maintains the turn-on state for the period in which the organic light emitting display device displays a predetermined image.

The second switch SW2 is positioned between the sensing unit 180 and the data line Dm. This second switch SW2 is turned on during the measurement period.

The sensing circuit 181 supplies a predetermined current to the pixel 140 during the measurement period. To this end, the sensing circuit 181 includes a current source unit 183 as shown in FIG. 7.

The current source unit 183 supplies the first current to the pixel 140 during the measurement period, and supplies the first voltage applied to the data line Dm to the ADC 182 when the first current is supplied. Here, since the first current flows through the organic light emitting diode OLED included in the pixel 140, the first voltage applied to the data line Dm has deterioration information of the organic light emitting diode OLED.

As the OLED degrades, the resistance value of the OLED increases. Therefore, the first voltage is changed in response to the deterioration of the organic light emitting diode OLED, and accordingly, the deterioration information of the organic light emitting diode OLED may be extracted. On the other hand, the current value of the first current is experimentally determined so that deterioration information of the OLED can be stably extracted. For example, the first current may be set to a current value that should flow to the organic light emitting diode OLED when the pixel 140 emits light at the maximum luminance.

The ADC 182 converts the first voltage supplied from the sensing circuit 181 into a first digital value and supplies it to the timing controller 150. Here, the ADC 182 may be installed for each channel, or all channels may use one ADC 182 in common. That is, at least one ADC 182 is installed.

The timing controller 150 stores the first digital value supplied from the ADC 182 in the memory 160. Here, the first digital value of each of all the pixels 140 is stored in the memory 160. The first digital value may be stored by changing a bit value by a separate algorithm.

The timing controller 150 compares the highest voltage among the first digital values stored in the memory 160 with the reference voltage and the voltage of the first digital value (ie, the first digital value extracted from the most degraded pixel). The power supply unit 190 is controlled to compensate for deterioration. In other words, the power supply unit 190 increases the voltage of the first power supply ELVDD or lowers the voltage of the second power supply ELVSS by the difference between the maximum voltage value and the reference voltage among the voltages measured from the pixels 140. The power supply unit 190 is controlled to lose. Here, the reference voltage refers to a voltage generated in the organic light emitting diode OLED in response to the first current before the organic light emitting diode OLED is deteriorated.

When the timing controller 150 increases the voltage of the first power supply ELVDD or decreases the voltage of the second power supply ELVSS, the degradation of the pixel 140 that is most degraded may be compensated. However, except for the most degraded pixel 140, the remaining pixels 140 generate light having a higher luminance than a desired luminance. To compensate for this, the timing controller 150 generates the second data Data2 using the first digital value of each pixel 140 stored in the memory 160. Here, the bit value of the second data Data2 is set such that light having the same luminance is generated in all the pixels 140. When light having the same luminance is generated in all the pixels 140, gradation is stably performed during digital driving, and deterioration of the organic light emitting diode may be compensated for.

The first digital value stored in the memory 160 is stored as a value of a predetermined bit, for example, 4 bits. Here, the first digital value has different bit values corresponding to the degree of degradation. For example, the first digital value of the highly degraded pixel 140 has a value of "0111", and the first digital value of the slightly degraded pixel 140 has a value of "0001".

Meanwhile, the first data Data1 supplied to the timing controller 150 includes light emission or non-light emission information of the pixel 140. For example, when the specific pixel 140 is not emitting light, the first data Data1 of "0" is supplied, and when the pixel emits light, the first data Data1 of "1" is supplied.

The timing controller 150 generates the second data Data2 so that the pixel 140 maintains the non-emission state when the first data Data1 of “0” is input corresponding to the specific pixel 140. Supply to 120. Then, the data driver 120 outputs the voltage of the data signal that the pixel 140 can not emit in response to the second data Data2 to the data line D. FIG.

The timing controller 150 sets the first digital value as the second data Data2 so that the pixel 140 maintains the light emission state when the first data Data1 of “1” is input corresponding to the specific pixel 140. Supply to the data driver 120. (The data driver 120 outputs a data signal having a lower voltage as the bit of the second data Data2 goes from “0000” to “1111” bit.) That is, in the present invention, the less the degradation, the higher the voltage of the data signal. In this case, light of uniform luminance is generated in all the pixels 140. The data driver 120 outputs a data signal corresponding to the bit of the first digital value to the data line D. FIG. In this case, a uniform image in which the voltage of the first power source ELVDD is increased or the voltage drop of the second power source ELVSS is compensated for and deterioration is compensated for is displayed.

In the above description, the first digital value is used as the second data Data2, but the present invention is not limited thereto. For example, the bit of the first digital value may be partially raised or lowered so that light of uniform luminance is generated in all the pixels 140.

The data driver 120 generates a data signal using the second data Data2 and supplies the generated data signal to the pixel 140.

FIG. 8 is a diagram illustrating an embodiment of a data driver shown in FIG. 2.

Referring to FIG. 8, the data driver 120 includes a shift register 121, a sampling latch 122, a holding latch 123, a signal generator 124, and a buffer 125.

The shift register unit 121 receives the source start pulse SSP and the source shift clock SSC from the timing controller 150. The shift register 121 supplied with the source shift clock SSC and the source start pulse SSP sequentially generates m sampling signals while shifting the source start pulse SSP every one period of the source shift clock SSC. . To this end, the shift register unit 121 includes m shift registers 1211 to 121m (for example, flip-flops).

The sampling latch unit 122 sequentially stores the second data Data2 in response to sampling signals sequentially supplied from the shift register unit 121. To this end, the sampling latch unit 122 includes m sampling latches 1221 to 122m to store m second data Data2.

The holding latch unit 123 receives a source output enable (SOE) signal from the timing controller 150. The holding latch unit 123 receiving the source output enable (SOE) signal receives and stores the second data Data2 from the sampling latch unit 122. The holding latch unit 123 supplies the second data Data2 stored therein to the signal generation unit 124. To this end, the holding latch unit 123 includes m holding latches 1231 to 123m.

The signal generator 124 receives the second data Data2 from the holding latch unit 123 and generates m data signals corresponding to the received second data Data2. To this end, the signal generator 124 includes m digital-to-analog converters (hereinafter, referred to as "DACs") 1241 to 124m. That is, the signal generator 124 generates m data signals using the DACs 1241 to 124m positioned for each channel, and supplies the generated data signals to the buffer unit 125.

The buffer unit 125 supplies m data signals supplied from the signal generator 124 to each of the m data lines D1 to Dm. To this end, the buffer unit 125 includes m buffers 1251 to 125m.

9A and 9B are diagrams showing driving waveforms supplied to the pixel and the switch unit.

9A is a diagram showing a drive waveform supplied during a measurement period.

9A and 10, the operation process will be described in detail. First, a voltage at which the second transistor M2 can be turned on before the measurement period is charged to the storage capacitor Cst. Thereafter, the voltage of the first power supply ELVDD is set to a voltage lower than the voltage of the second power supply ELVSS. Then, the reverse bias voltage is applied to the organic light emitting diode (OLED) to restore the device characteristics of the organic light emitting diode (OLED). In fact, when the reverse bias voltage is applied to the organic light emitting diode (OLED), the organic The degradation rate of the light emitting diode OLED is slowed down.

Thereafter, the first switch SW1 is turned off during the measurement period, and the second switch SW2 is kept turned on. When the second switch SW2 is turned on, the current source unit 183 and the data line Dm are electrically connected to each other.

Thereafter, the scan signal is supplied to the scan line Sn and the control signal is supplied to the control line CLn. When the scan signal is supplied to the scan line CLn, the first transistor M1 is turned on. When the control signal is supplied to the control line CLn, the third transistor M3 is turned on.

In this case, the current source unit 183 supplies the first current to the second power source ELVSS via the second switch SW2, the third transistor M3, and the organic light emitting diode OLED. When the first current is supplied from the current source unit 183, a first voltage is generated in the OLED. The first voltage includes deterioration information of the organic light emitting diode OLED.

Meanwhile, since the first transistor M1 and the third transistor M3 are turned on, the second transistor M2 is connected in the form of a diode. In this case, since the voltage of the first power supply ELVDD is set to a low voltage, the second transistor M2 is set to the turn-off state.

The first voltage generated in the organic light emitting diode OLED is supplied to the ADC 182. The ADC 182 converts the first voltage into a first digital value and supplies it to the timing controller 150. The timing controller 150 stores the first digital value in the memory 160. In fact, during the measurement period, the scan signals are sequentially supplied to the scan lines S1 to Sn, and the control signals are sequentially supplied to the control lines CL1 to CLn, and the organic light emitting diodes included in each of the pixels 140 ( Deterioration information of the OLED) is stored in the memory 160 as the first digital value.

In the present invention, the measurement period is determined by the designer predetermined time. For example, a measurement period may be arranged in an initial period during which power is supplied to the organic light emitting display device.

Meanwhile, although it is assumed that the voltage of the first power supply ELVDD is set to be lower than the voltage of the second power supply ELVSS during the measurement period, the present invention is not limited thereto. In fact, the voltage of the first power source ELVDD is set to a voltage lower than that of the second power source ELVSS during the device characteristic recovery period, but the voltage of the first power source ELVDD is lower than that of the second power source ELVDD during the measurement period. It may be set equal to or higher than the voltage.

9B is a diagram showing a drive waveform supplied to the display period.

9B and 10, the voltage of the first power source ELVDD is set to a voltage higher than the voltage of the second power source ELVSS during the display period. When the voltage of the first power supply ELVDD is set to a voltage higher than the voltage of the second power supply ELVSS, a current corresponding to the voltage stored in the storage capacitor Cst may be supplied to the organic light emitting diode OLED.

In the meantime, during the display period, the power source unit 190 controls the first power source ELVDD by a difference between the reference voltage and the maximum voltage value included in the first digital value in response to the highest first digital value. Raise the voltage or lower the voltage of the second power supply ELVSS.

Thereafter, the first data Data1 including the emission and non-emission information of the pixels 140 is supplied to the timing controller 150 during the display period. The timing controller 150 extracts, from the memory 160, the first digital value extracted from the pixel 140 to which the currently supplied first data Data1 is to be supplied, and the second data Data2 for which degradation is compensated for. Generates and supplies it to the data driver 120.

The second data Data2 generated by the timing controller 150 is supplied to the DAC 124m via the sampling latch 122m and the holding latch 123m. Then, the DAC 124m generates a data signal using the second data Data2 and supplies the generated data signal to the data line Dm via the buffer 125m.

Here, since the scan signal is supplied to the scan line Sn and the first transistor M1 is turned on, the data signal supplied to the data line Dm is supplied to the gate electrode of the second transistor M2. In this case, the storage capacitor Cst charges a voltage corresponding to the data signal. Thereafter, the second transistor M2 supplies a current corresponding to the voltage charged in the storage capacitor Cst to the organic light emitting diode OLED.

In fact, during the display period, scan signals are sequentially supplied to the scan lines S1 to Sn during the scan time of the subfields SF1 to SF8 shown in FIG. 3, and current is supplied to the organic light emitting diode OLED during the light emitting period. While displaying the image of a predetermined brightness.

Although the technical idea of the present invention has been described in detail according to the above preferred embodiment, it should be noted that the above-described embodiment is for the purpose of description and not of limitation. In addition, those skilled in the art will understand that various modifications are possible within the scope of the technical idea of the present invention.

1 is a circuit diagram showing a conventional pixel.

2 is a diagram illustrating an organic light emitting display device according to an exemplary embodiment of the present invention.

3 is a view showing one frame according to an embodiment of the present invention.

4 is a diagram illustrating an embodiment of a pixel illustrated in FIG. 2.

FIG. 5 is a diagram illustrating an embodiment of the pixel circuit shown in FIG. 4.

6 is a view illustrating in detail the switching unit and the sensing unit shown in FIG.

FIG. 7 is a diagram illustrating a configuration of the sensing circuit of FIG. 6.

FIG. 8 is a diagram illustrating an embodiment of a data driver shown in FIG. 2.

9A and 9B are diagrams illustrating driving waveforms according to an exemplary embodiment of the present invention.

10 is a diagram illustrating a connection structure between a sensing unit and a pixel.

<Explanation of symbols for the main parts of the drawings>

2,142: pixel circuit 4,140: pixel

110: scan driver 120: data driver

121: shift register section 122: sampling latch section

123: holding latch unit 124: signal generating unit

125: buffer portion 130: pixel portion

150: timing controller 160: memory

170: switching unit 180: sensing unit

181: sensing circuit 182: ADC

183: current source unit 190: power supply unit

Claims (18)

Pixels positioned at an intersection of the data lines, the scan lines, and the control lines; The scan signal is sequentially supplied to the scan lines during the measurement period and the control signal is sequentially supplied to the control lines, and the scan lines are scanned between the respective syringes of each of the plurality of subfields included in one frame during the display period. A scan driver for sequentially supplying signals; A data driver supplying data signals generated using second data supplied from a timing controller to the data lines during the display period; A sensing unit for measuring degradation information of the organic light emitting diode included in each of the pixels; A switching unit for connecting any one of the sensing unit and the data driver to the data lines; A memory for storing the deterioration information; A timing controller which stores the deterioration information in the memory, controls a power supply unit using the deterioration information, and generates second data using the deterioration information and first data supplied from the outside; And a power supply unit for adjusting a voltage value of the first power supply or the second power supply in response to the control of the timing controller. The method of claim 1, And the sensing unit includes a current source unit positioned in each channel. The method of claim 2, And the sensing unit comprises at least one analog-digital converter for changing a first voltage generated when a first current is supplied from the current source unit to the pixel to a first digital value. The method of claim 3, wherein And the first digital value includes the deterioration information. The method of claim 2, The switch unit A second switch located between the current source unit and the data line and turned on during the measurement period; And a first switch disposed between the data driver and the data line and turned on during the display period. The method of claim 3, wherein The timing controller raises the first power source or lowers the second power source by a difference between a reference voltage measured before the organic light emitting diode deteriorates and a voltage of the first digital value extracted from the most degraded pixel. An organic light emitting display device comprising: The method of claim 6, The timing controller generates the second data by using a first digital value corresponding to the specific pixel stored in the memory when the first data to be supplied to the specific pixel means light emission of the specific pixel. Organic electroluminescent display. The method of claim 7, wherein And the bit value of the second data is set such that light having the same luminance is generated in all the pixels. The method of claim 7, wherein And the bit value of the second data is set such that a data signal having a low voltage is generated as the first digital value is higher. The method of claim 1, Each of the pixels The organic light emitting diode; A pixel circuit for controlling an amount of current flowing from the first power supply to the second power supply via the organic light emitting diode; And a third transistor connected between the anode electrode of the organic light emitting diode and the data line and turned on when a control signal is supplied to the control line. The method of claim 10, The pixel circuit A first transistor connected to the scan line and the data line and turned on when a scan signal is supplied to the scan line; A storage capacitor for charging a voltage corresponding to the data signal supplied to the data line; And a second transistor for supplying a current corresponding to the voltage stored in the storage capacitor to the organic light emitting diode. The method of claim 1, And the power supply unit sets the voltage of the first power supply to be lower than the voltage of the second power supply during the device characteristic restoration period before the measurement period. The method of claim 1, And the measuring period is arranged in an initial period during which power is supplied to the organic light emitting display. 1. A method of driving an organic light emitting display device, comprising: pixels, each frame being divided into a plurality of subfields, for controlling an amount of current flowing from a first power supply to a second power supply via an organic light emitting diode; Setting the voltage of the first power supply to be lower than the voltage of the second power supply during the device characteristic recovery period; Supplying a first current to an organic light emitting diode included in each of the pixels during a measurement period, and changing a first voltage generated corresponding to the first current to a first digital value; Setting the voltage of the first power supply to be higher than the voltage of the second power supply for a display period; The voltage of the first power supply is increased or the second voltage is increased by a difference between a maximum voltage value of the measured first voltages and a reference voltage applied corresponding to the first current before the organic light emitting diode deteriorates. Lowering the voltage of the power supply; And generating second data using the first data supplied from the outside, and generating a data signal using the second data. The method of claim 14, And a voltage at which a driving transistor is turned on is charged in a storage capacitor included in each of the pixels during the device characteristic recovery period. The method of claim 14, And a bit value of the second data is set such that light having the same luminance is generated in all the pixels. The method of claim 14, The first digital value is set to a higher value as the organic light emitting diode deteriorates. The method of claim 17, And a bit value of the second data is set such that a data signal having a low voltage is generated as the first digital value is higher.

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