KR20170081048A - Organic light emitting display device and method for driving the organic light emitting display device - Google Patents

Abstract

The present invention relates to a method of driving an organic light emitting diode (OLED) display and an organic light emitting diode (OLED) display device, By generating sensed data on the characteristic values of the transistors or extracting some sensed values in each sensing period and combining sensed sensed values to generate sensed data, the error of the sensed value due to the power ripple applied when sensing the characteristic value of the driving transistor The influence on the sensing data can be minimized and the screen failure due to the compensation due to the error of the sensing value can be prevented.

Description

TECHNICAL FIELD [0001] The present invention relates to an organic light emitting diode (OLED) display device,

The present embodiments relate to an organic light emitting display and a method of driving the organic light emitting display.

BACKGROUND ART [0002] Organic light emitting displays (OLEDs), which have been popular as display devices in recent years, have advantages of high response speed, high contrast ratio, luminous efficiency, luminance and viewing angle by using an organic light emitting diode (OLED)

The OLED display includes an OLED display panel having a plurality of gate lines and a plurality of data lines and a plurality of subpixels arranged in a region where gate lines and data lines cross each other, A data driver for driving a plurality of data lines, a timing controller for controlling driving of a gate driver and a data driver, and the like. The plurality of sub pixels may include an organic light emitting diode (OLED) And a driving transistor for driving the diode OLED.

In such an OLED display device, circuit elements such as an organic light emitting diode (OLED) and a driving transistor included in each subpixel have unique characteristic values (e.g., threshold voltage, mobility) And the inherent characteristic value may be changed.

Such a change in the characteristic value of the circuit element causes a luminance deviation between each sub-pixel including the circuit element, thereby deteriorating the overall luminance uniformity of the organic light emitting display panel.

In order to solve such a problem, a technique of sensing characteristic values of circuit elements included in each sub pixel and compensating for the characteristic values of the circuit elements based on the sensed values has been applied.

The characteristic value sensing of the circuit elements progresses sequentially for each gate line by the operation of the gate line, and various power sources for sensing the characteristic value of the circuit element are applied in the same time period.

At this time, a ripple may occur in a power source applied for sensing the characteristic value of the circuit element. When ripple occurs in the power source, an error term is generated in the characteristic value sensing value of the circuit element due to reflow, The error of the compensation value affects the compensation value.

Therefore, erroneous characteristic value sensing and compensation are performed due to the ripple of the power supplied when sensing the characteristic value of the circuit element, and there is a problem that a screen failure such as a horizontal line shape occurs on the screen due to erroneous compensation.

It is an object of the present embodiments to provide an organic light emitting display device that minimizes an error of a sensing value due to power supply ripple applied when sensing a driving transistor characteristic value included in a subpixel disposed in an organic light emitting display panel.

It is an object of the present embodiments to prevent erroneous compensation of a characteristic value of a driving transistor due to power supply ripple applied at the time of sensing a characteristic value of a driving transistor included in a sub-pixel arranged in an organic light emitting display panel, Emitting display device according to the present invention.

In one embodiment, a plurality of sub-pixels including N (N? 2) gate lines and M (M? 2) data lines crossing each other and including driving transistors for driving the organic light emitting diodes and the organic light emitting diodes A gate driver for driving the N gate lines, a data driver for driving the M data lines, a gate driver for sensing characteristic values of the driving transistors by gate lines, And a sensing unit for generating one sensing data for a characteristic value of the driving transistor using one or more sensing values.

In the organic light emitting diode display, the sensing unit may generate sensing data for a characteristic value of the driving transistor with an average value of two or more sensed values of characteristic values of the driving transistor, or generate maximum and minimum values at three or more sensed values Sensing the characteristic value of the driving transistor by a number corresponding to a multiple of the ratio of the number of subpixels and the number of sensing lines for sensing the characteristic value of the driving transistor, And one sensing data for the characteristic value of the driving transistor can be generated using the sensed value.

In such an organic light emitting display, the sensing unit senses the characteristic value of the driving transistor N times in a separate sensing period, and detects the Xth sensing of the driving transistor included in the subpixel driven by the gate line of X (1? X? N) (1 ≤ Y ≤ M) rows driven by the data lines in the Y The sensing data for the characteristic value of the driving transistor can be generated with the Y-th sensing value of the transistor.

Another embodiment is an organic light emitting display including an organic light emitting display panel in which a plurality of gate lines and a plurality of data lines are crossed and a plurality of sub pixels including a driving transistor for driving the organic light emitting diode A method of driving a display device, the method comprising: sensing characteristic values of a driving transistor sequentially on a gate line by gate line basis; and sensing one characteristic value of a driving transistor by using two or more sensed values sensed in a separate sensing period And generating sensing data based on the sensing data.

According to the embodiments, the influence of the power ripple applied when sensing the characteristic value of the driving transistor can be minimized by changing the characteristic value sensing method of the driving transistor included in the sub pixel arranged in the organic light emitting display panel.

According to the embodiments, by minimizing the influence of the power ripple applied at the time of sensing the characteristic value of the driving transistor included in the sub-pixel arranged in the organic light emitting display panel, .

FIG. 1 is a diagram showing a schematic configuration of an organic light emitting display according to the present embodiments.
2 is a diagram illustrating an example of a sub-pixel structure of an OLED display according to an exemplary embodiment of the present invention.
3 is a diagram illustrating an example of a sub-pixel structure and a compensation circuit of an organic light emitting display according to the present embodiments.
4 and 5 are views for explaining the characteristic value sensing of the driving transistor in the sub-pixel of the OLED display according to the present embodiments.
6 is a diagram for explaining a period for sensing a characteristic value of a driving transistor in a sub-pixel of the organic light emitting diode display according to the present embodiments.
7 is a view for explaining an error due to a power supply ripple applied to a driving transistor in a sub-pixel of the organic light emitting diode display according to the present invention and a screen failure.
8 and 9 are views showing an example of a characteristic value sensing method of a driving transistor in a sub-pixel of the organic light emitting display according to the present embodiments.
FIGS. 10 and 11 are flowcharts illustrating a method of driving an organic light emitting display according to an exemplary embodiment of the present invention. Referring to FIG.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. In the drawings, like reference numerals are used to denote like elements throughout the drawings, even if they are shown on different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

In describing the components of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are intended to distinguish the components from other components, and the terms do not limit the nature, order, order, or number of the components. When a component is described as being "connected", "coupled", or "connected" to another component, the component may be directly connected or connected to the other component, Quot; intervening "or that each component may be" connected, "" coupled, "or " connected" through other components.

FIG. 1 shows a schematic configuration of an OLED display 100 according to the present embodiments.

Referring to FIG. 1, the organic light emitting diode display 100 according to the present embodiment includes a plurality of (N, N? 2) gate lines GL and a plurality (M, M = 4m? An organic light emitting display panel 110 including a plurality of subpixels SP in which a line DL is arranged and an area where a gate line GL and a data line DL intersect each other and a plurality of gate lines GL A data driver 130 for supplying a data voltage to the plurality of data lines DL; a timing controller 140 for controlling the gate driver 120 and the data driver 130; T-CON).

The gate driver 120 sequentially drives the plurality of gate lines GL by sequentially supplying scan signals to the plurality of gate lines GL.

The gate driver 120 sequentially supplies a scan signal of an ON voltage or an OFF voltage to the plurality of gate lines GL in accordance with the control of the timing controller 140, Respectively.

The gate driver 120 may be located on one side or both sides of the organic light emitting display panel 110 according to the driving method.

In addition, the gate driver 120 may include one or more gate driver integrated circuits.

Each gate driver integrated circuit may be connected to a bonding pad of the organic light emitting display panel 110 by a tape automated bonding (TAB) method or a chip on glass (COG) method, (Gate In Panel) type and may be directly disposed on the organic light emitting display panel 110. The organic light emitting display panel 110 may be integrated with the organic light emitting display panel 110 or may be implemented as a chip on film (COF) method mounted on a film connected to the organic light emitting display panel 110.

The data driver 130 drives the plurality of data lines DL by supplying data voltages to the plurality of data lines DL.

When the specific gate line GL is opened, the data driver 130 converts the image data received from the timing controller 140 into analog data voltages and supplies the data voltages to the plurality of data lines DL, .

The data driver 130 may include at least one source driver integrated circuit to drive a plurality of data lines DL.

Each source driver integrated circuit may be connected to a bonding pad of the organic light emitting display panel 110 by a tape automated bonding (TAB) method or a chip on glass (COG) And may be directly disposed on the organic light emitting display panel 110 or may be integrated on the organic light emitting display panel 110. [

In addition, each source driver integrated circuit may be implemented by a chip on film (COF) method. In this case, one end of each source driver integrated circuit is bonded to at least one source printed circuit board, and the other end is bonded to the organic light emitting display panel 110.

The timing controller 140 supplies various control signals to the gate driver 120 and the data driver 130 to control the driving of the gate driver 120 and the data driver 130.

The timing controller 140 starts scanning according to the timing implemented in each frame, switches the input image data input from the outside according to the data signal format used by the data driver 130, and outputs the converted image data And controls the data driving at a proper time according to the scan.

The timing controller 140 outputs various timing signals including a vertical synchronization signal Vsync, a horizontal synchronization signal Hsync, an input data enable (DE) signal, a clock signal CLK, (E.g., a host system).

The timing controller 140 may switch the input video data inputted from the outside according to the data signal format used by the data driver 130 and output the converted video data to the gate driver 120 and the data driver 130 A timing signal such as a vertical synchronization signal Vsync, a horizontal synchronization signal Hsync, an input data enable signal DE and a clock signal CLK to generate various control signals, (120) and the data driver (130).

For example, in order to control the gate driver 120, the timing controller 140 generates a gate start pulse (GSP), a gate shift clock (GSC), a gate output enable signal GOE : Gate Output Enable), and the like.

Here, the gate start pulse GSP controls the operation start timing of one or more gate driver integrated circuits constituting the gate driver 120. The gate shift clock GSC is a clock signal commonly input to one or more gate driver integrated circuits, and controls the shift timing of the scan signal (gate pulse). The gate output enable signal GOE specifies the timing information of one or more gate driver ICs.

The timing controller 140 includes a source start pulse SSP, a source sampling clock SSC, a source output enable signal SOE, Output enable (DCS) data control signals.

Here, the source start pulse SSP controls the data sampling start timing of one or more source driver integrated circuits constituting the data driver 130. The source sampling clock SSC is a clock signal for controlling sampling timing of data in each of the source driver integrated circuits. The source output enable signal SOE controls the output timing of the data driver 130.

The timing controller 140 is connected to a source printed circuit board to which a source driver integrated circuit is bonded and a control printed circuit (not shown) connected via a connection medium such as a flexible flat cable (FFC) or a flexible printed circuit And may be disposed on a substrate (Control Printed Circuit Board).

A power controller (not shown) for controlling various voltages or currents to supply or supply various voltages or currents to the organic light emitting display panel 110, the gate driver 120, the data driver 130, . These power controllers are also referred to as power management integrated circuits.

Each sub-pixel SP disposed in the organic light emitting display panel 110 may include a circuit element such as a transistor.

For example, in the organic light emitting display panel 110, each subpixel SP is composed of circuit elements such as a driving transistor (DRT) for driving the organic light emitting diode OLED and the organic light emitting diode OLED .

The types and the number of the circuit elements constituting each subpixel SP can be variously determined depending on a providing function, a design method, and the like.

2 shows an example of the sub-pixel (SP) structure of the organic light emitting diode display 100 according to the present embodiments.

2, each of the sub-pixels SP includes an organic light emitting diode OLED, a driving transistor DRT for driving the organic light emitting diode OLED, And a sensing transistor SENT which is electrically connected between a first node N1 of the driving transistor DRT and a reference voltage line RVL for supplying a reference voltage Vref A switching transistor SWT electrically connected between a second node N2 of the driving transistor DRT and a data line DL supplying a data voltage Vdata; And a storage capacitor Cstg electrically connected between the first node N1 and the second node N2.

The organic light emitting diode OLED may include a first electrode (e.g., an anode electrode or a cathode electrode), an organic layer, and a second electrode (e.g., a cathode electrode or an anode electrode).

The driving transistor DRT supplies a driving current to the organic light emitting diode OLED to drive the organic light emitting diode OLED.

The first node N1 of the driving transistor DRT may be electrically connected to the first electrode of the organic light emitting diode OLED and may be a source node or a drain node. The second node N2 of the driving transistor DRT may be electrically connected to the source node or the drain node of the switching transistor SWT and may be a gate node. The third node N3 of the driving transistor DRT may be electrically connected to a driving voltage line DVL for supplying a driving voltage EVDD and may be a drain node or a source node.

The sensing transistor SENT may be turned on by a gate signal to apply the reference voltage Vref to the first node N1 of the driving transistor DRT.

In addition, the sensing transistor SENT may be utilized as a voltage sensing path for the first node N1 of the driving transistor DRT when turned on.

The switching transistor SWT transfers the data voltage Vdata supplied through the data line DL to the second node N2 of the driving transistor DRT when the switching transistor SWT is turned on by the gate signal.

At this time, the sensing transistor SENT and the switching transistor SWT may be connected to different gate lines GL so that the sensing transistor SENT and the switching transistor SWT may be separately controlled to be turned on and off or may be connected to the same gate line GL to be controlled.

The storage capacitor Cstg is electrically connected between the first node N1 and the second node N2 of the driving transistor DRT and supplies a data voltage Vdata corresponding to the video signal voltage or a voltage corresponding thereto You can keep it for one frame time.

In the OLED display 100 according to the present embodiment, as the driving time of each sub-pixel SP becomes longer, the driving voltage of the organic light emitting diode OLED, the driving transistor DRT, Degradation can proceed.

Accordingly, inherent characteristic values (e.g., threshold voltage, mobility, etc.) of the circuit elements such as the organic light emitting diode OLED and the driving transistor DRT can be changed.

A change in the characteristic value of the circuit element causes a luminance change of the corresponding sub-pixel SP, and a difference in characteristic value between the circuit elements due to a difference in degree of deterioration between the circuit elements generates a luminance deviation between the sub- The luminance uniformity of the panel 110 may be lowered.

Here, the characteristic value of the circuit element includes the threshold voltage and the mobility of the driving transistor DRT and may include the threshold voltage of the organic light emitting diode OLED.

The OLED display 100 according to the present embodiment includes a sensing function for sensing a characteristic value variation between subpixels SP or a characteristic value deviation between each subpixel SP, Can be provided.

FIG. 3 shows an example of a sub-pixel (SP) structure and a compensation circuit of the organic light emitting diode display 100 according to the present embodiments.

3, the OLED display 100 according to the present embodiment includes a sensing unit 310, a compensation unit 320, a memory 330, and a driving unit 330 for sensing and compensating the characteristic value of the subpixel SP. A reference voltage switch SPRE and a sampling switch SAMP.

The sensing unit 310 senses a characteristic value of the sub-pixel SP or a voltage for sensing the change, converts the sensed voltage into a digital value, and outputs sensed data including the sensed sensed value.

Here, the characteristic value of the subpixel SP means the threshold voltage and the mobility of the driving transistor DRT and the threshold voltage of the organic light emitting diode OLED, and the sensing data is in a low voltage differential signaling (LVDS) data format .

The sensing unit 310 may include at least one analog-to-digital converter (ADC). Each analog-to-digital converter (ADC) may be included inside the source driver integrated circuit, and in some cases, it may be disposed outside the source driver integrated circuit.

The compensation unit 320 performs a compensation process for compensating for the characteristic value deviation between the subpixels SP by sensing the characteristic value or the change of the subpixel SP using the sensing data output from the sensing unit 310. [

The compensation unit 320 may be included in the timing controller 140 and may be disposed outside the timing controller 140 in some cases.

The memory 330 may store the sensing data output from the sensing unit 310 and may store the compensation value calculated by the compensating unit 320 based on the sensing data.

The reference voltage switch SPRE controls the supply of the reference voltage Vref to the reference voltage line RVL and the sampling switch SAMP controls the supply of the reference voltage Vref to the reference voltage line RVL in order to sense the voltage for sensing the characteristic value of the sub- And controls the connection between the voltage line RVL and the sensing unit 310.

When the reference voltage switch SPRE is turned on, the reference voltage Vref is supplied to the reference voltage line RVL. The reference voltage Vref supplied to the reference voltage line RVL may be applied to the first node N1 of the driving transistor DRT through the sensing transistor SENT which is turned on.

On the other hand, when the voltage of the first node N1 of the driving transistor DRT becomes a voltage state reflecting the characteristic value of the subpixel SP, a reference potential that can be equal to the first node N1 of the driving transistor DRT The voltage of the voltage line RVL may also be a voltage state reflecting the characteristic value of the subpixel SP. At this time, the line capacitor formed on the reference voltage line RVL may be charged with a voltage reflecting the characteristic value of the subpixel SP.

That is, when the sensing transistor SENT is turned on, the voltage of the first node N1 of the driving transistor DRT is lower than the voltage of the reference voltage line RVL and the voltage of the line RVL formed on the reference voltage line RVL. The voltage charged in the capacitor may be the same.

When the voltage of the first node N1 of the driving transistor DRT becomes a voltage state reflecting the characteristic value of the sub pixel SP, the sampling switch SAMP is turned on, (RVL) can be connected.

Accordingly, the sensing unit 310 senses the voltage of the reference voltage line RVL in a voltage state reflecting the characteristic value of the sub-pixel SP. Here, the reference voltage line RVL may be referred to as a "sensing line SL ".

That is, the sensing unit 310 senses the voltage of the first node N1 of the driving transistor DRT.

The voltage sensed by the sensing unit 310 may be a voltage value including a threshold voltage Vth or a threshold voltage change DELTA Vth of the driving transistor DRT in the case of threshold voltage sensing for the driving transistor DRT.

The voltage sensed by the sensing unit 310 may be a voltage value for sensing the mobility of the driving transistor DRT in the case of mobility sensing for the driving transistor DRT.

The voltage sensed by the sensing unit 310 may be a voltage that reflects a threshold voltage, which is a characteristic value of the organic light emitting diode OLED.

Hereinafter, the sensing process of the threshold voltage and the sensing process of the mobility of the driving transistor DRT will be described with reference to FIGS.

4 is a view for explaining a method of sensing a threshold voltage of the driving transistor DRT of the OLED display 100 according to the present embodiments.

4, when driving the threshold voltage sensing of the driving transistor DRT, the first node N1 and the second node N2 of the driving transistor DRT respectively output the reference voltage Vref and the sensing data voltage Vdata).

Thereafter, when the reference voltage switch SPRE is turned off, the first node N1 of the driving transistor DRT is floated.

As a result, the voltage of the first node N1 of the driving transistor DRT rises.

The voltage of the first node N1 of the driving transistor DRT rises and then the rising width gradually decreases and becomes saturated.

The saturated voltage of the first node N1 of the driving transistor DRT may correspond to the difference between the data voltage Vdata and the threshold voltage Vth or the difference between the data voltage Vdata and the threshold voltage deviation Vth .

The sensing unit 310 senses the saturated voltage of the first node N1 of the driving transistor DRT when the voltage of the first node N1 of the driving transistor DRT becomes saturated.

The voltage Vsen sensed by the sensing unit 310 may be a voltage (Vdata-Vth) obtained by subtracting the threshold voltage (Vthata) from the data voltage (Vdata), or a voltage obtained by subtracting the threshold voltage deviation (Vdata -? Vth).

5 is a view for explaining a method of sensing the mobility of the driving transistor DRT of the OLED display 100 according to the present embodiments.

5, the first node N1 and the second node N2 of the driving transistor DRT sense the reference voltage Vref and the data voltage for sensing Vdata).

Thereafter, when the reference voltage switch SPRE is turned off, the first node N1 of the driving transistor DRT is floated. At this time, the switching transistor SWT is turned off so that the second node N2 of the driving transistor DRT can also be floated.

As a result, the voltage of the first node N1 of the driving transistor DRT starts to rise.

The voltage rising width DELTA V of the first node N1 of the driving transistor DRT is a voltage rising speed and varies depending on the current capability of the driving transistor DRT, that is, the mobility.

That is, the voltage of the first node N1 of the driving transistor DRT increases more steeply with the driving transistor DRT having a higher current capability (mobility), and the voltage of the first node N1 ) Is large.

After the voltage of the first node N1 of the driving transistor DRT rises for a predetermined period of time, the sensing unit 310 senses the voltage of the first node N1 of the driving transistor DRT .

The rate of change per unit time of the voltage rise width? V according to the voltage Vsen sensed by the sensing unit 310, that is, the slope may be the mobility.

The sensing unit 310 converts the sensed voltage Vsen into a digital value according to the threshold voltage or mobility sensing drive, and generates and outputs sensing data including the sensed sensing value. The sensing data output from the sensing unit 310 may be stored in the memory 330 or may be provided to the compensating unit 320.

The compensation unit 320 is configured to grasp a characteristic value or a characteristic value change of the driving transistor DRT in the corresponding subpixel SP based on the sensing data provided by the sensing unit 310 or the sensing data stored in the memory 330, Lt; / RTI >

The characteristic value compensation process may include a threshold voltage compensation process for compensating the threshold voltage of the driving transistor DRT and a mobility compensation process for compensating the mobility of the driving transistor DRT.

The threshold voltage compensation process may include a process of calculating a compensation value for compensating for a threshold voltage or a threshold voltage deviation and storing the calculated compensation value in the memory 330 or changing the corresponding video data with the calculated compensation value have.

The mobility compensation process includes a process of calculating a compensation value to compensate for mobility or mobility deviation, storing the calculated compensation value in the memory 330, or changing the corresponding image data with the calculated compensation value .

The compensation unit 320 may change the image data through the threshold voltage compensation process or mobility compensation process and supply the changed data to the corresponding source driver integrated circuit in the data driver 130. [

Accordingly, the source driver integrated circuit converts the data changed by the compensation unit 320 into a data voltage through a digital to analog converter (DAC) and supplies the data voltage to the corresponding subpixel SP, SP) to be compensated for.

By compensating the characteristic values of the sub-pixels SP, the luminance deviation between the sub-pixels SP is reduced or prevented, thereby improving the luminance uniformity of the organic light emitting display panel 110 and improving the image quality.

6 is a timing chart for sensing the sub-pixel SP characteristic values of the OLED display 100 according to the present embodiment.

Referring to FIG. 6, the organic light emitting display 100 according to the present embodiment includes a plurality of sub-pixels SP disposed in the organic light emitting display panel 110 after a power- The characteristic value of the circuit element can be sensed.

In this way, the ongoing sensing after the power-off signal is generated is referred to as " off-sensing ".

In addition, the organic light emitting display 100 according to the present embodiment may be configured such that a power-on signal is generated according to a user input or the like, SP) can be sensed.

As described above, the sensing that is performed before the image driving is progressed after the power-off signal is generated is referred to as " on-sensing ".

The organic light emitting diode display 100 according to the present exemplary embodiments may sense characteristic values of circuit elements in each subpixel SP disposed in the organic light emitting display panel 110 during image driving.

As described above, the sensing progressed during the image driving is called "real-time sensing ".

This real-time sensing may be performed for each blank time between active times based on the vertical synchronization signal Vsync.

Since the threshold voltage sensing of the driving transistor DRT during the sensing of the characteristic value of the subpixel SP senses the voltage in the saturated state of the first node N1 of the driving transistor DRT in the sensing period, Since a certain time is required for one node N1 to become saturated, it can be performed in an off-sensing manner.

Since the sensing of the mobility of the driving transistor DRT can be performed in a relatively short time, the sensing can be performed in real time using blank time during image driving.

Ripple is generated in a power source such as a sensing data voltage Vdata or a reference voltage Vref applied to sense the characteristic value of the driving transistor DRT in the process of sensing the characteristic value of the driving transistor DRT. There is a number.

When a ripple is generated in the applied power source in order to sense the characteristic value of the driving transistor DRT, the power ripple affects the voltage sensed at the first node N1 of the driving transistor DRT, An error term may be included in the sensing data generated based on the voltage of N1.

The error of the sensing data is reflected in the compensation value calculated on the basis of the sensing data so that the characteristic value of the driving transistor DRT is erroneously compensated.

FIG. 7 illustrates an example of a defective display caused by a ripple of a power source applied when sensing the characteristic value of the driving transistor DRT in the sub-pixel SP of the OLED display 100 according to the present embodiments.

Referring to FIG. 7, when ripples are generated in the power source applied at the time of sensing the characteristic value of the driving transistor DRT, the power ripple affects the voltage sensed by the sensing unit 310, and the sensing unit 310 includes an error To generate sensing data.

When the sensing unit 310 outputs sensing data for the characteristic value of the driving transistor DRT to a larger value than the peripheral unit due to the influence of the power supply ripple, the compensating unit 320 compares the characteristic value of the driving transistor DRT And the compensation value for the first and second reference signals is small. Therefore, since the compensation for the characteristic value of the driving transistor DRT is performed small, the sub-pixel SP including the driving transistor DRT after compensation can be represented as a dark spot.

When the sensing unit 310 outputs sensing data for the characteristic value of the driving transistor DRT to a smaller value than the peripheral unit due to the influence of the power supply ripple, the compensation unit 320 compares the characteristic value So that the subpixel SP including the driving transistor DRT after the compensation can be represented as a luminescent spot.

Since the sensing of the characteristic value of the driving transistor DRT is performed for each gate line GL disposed in the organic light emitting display panel 110, It appears in the form of a dark line or a bright line.

In the present exemplary embodiment, in sensing the characteristic value of the driving transistor DRT in the sub-pixel SP and compensating the characteristic value of the driving transistor DRT based on the sensed value, It is possible to generate sensing data on the characteristic value of the driving transistor DRT through various sensing methods so as to prevent an error of data and a screen failure due to the error.

8 and 9 show an example of a method of sensing the characteristic value of the driving transistor DRT in the subpixel SP of the organic light emitting diode display 100 according to the present embodiment. And generates a sensing data using at least two sensed values of the sensed data for sensing, thereby minimizing an error of sensing data due to power supply ripple applied at the time of sensing.

Referring to FIG. 8, the OLED display 100 according to the exemplary embodiment of the present invention senses a characteristic value of the driving transistor DRT in the sub-pixel SP two or more times and uses an average value of the sensed values twice or more It is possible to generate one sensing data for the characteristic value of the driving transistor DRT.

For example, the sensing unit 310 senses the gate line GL by sensing the characteristic value of the driving transistor DRT, and stores the sensed value in the first sensing period. Then, the second sensing is performed on the characteristic value of the driving transistor DRT in a separate sensing period, and the sensed value is stored in the second sensing period.

The sensing unit 310 calculates an average value of the sensed value in the first sensing period and a sensed value in the second sensing period and generates one sensing data for the characteristic value of the driving transistor DRT using the calculated average value .

By using the fact that the error of the sensing value due to the power supply ripple is not repeatedly generated in the same gate line GL, one sensing data is generated as an average value of two or more sensing values sensed in a separate sensing period, So as to minimize the influence of the error.

8, even if a sensing value error due to a power ripple occurs in a value sensed in a first sensing interval and a value sensed in a second sensing interval, sensing data is generated from the average value of the two sensing values, The influence due to the error of the value can be eliminated.

In order to further reduce the error of the sensing value due to the power supply ripple, the number of times of sensing the characteristic value of the driving transistor DRT is increased and the sensing data is generated with the average value of the sensing values obtained, The influence on the data can be further reduced.

In this case, even if the number of sensing is increased, as the number of sensing increases, the number of errors of the sensing value due to the power supply ripple also increases. Even if the sensing data is generated using the average value of the various sensing values, The influence due to the error of the value may remain.

Therefore, in generating one sensing data for the characteristic value of the driving transistor DRT by an average value of a plurality of sensing values sensed in a separate sensing period, the maximum value and the minimum value of the plurality of sensing values are excluded, May be used to generate one sensing data.

That is, the sensing data for the characteristic value of the driving transistor DRT is generated by using the remaining sensing values except for the sensing value expected to cause an error due to the power supply ripple applied at the time of sensing the characteristic value of the driving transistor DRT, It is possible to minimize the influence of the error of the value and improve the reliability of the generated sensing data.

The sensing line SL for sensing the characteristic value of the driving transistor DRT in the subpixel SP disposed in the organic light emitting display panel 110 may be arranged for each subpixel SP, The sensing line SL may be connected to two or more subpixels SP to sense the characteristic value of the driving transistor DRT included in the subpixel SP.

In this case, in order to sense the characteristic value of each driving transistor DRT, it is necessary to sense the number of times corresponding to the number of the sub-pixels SP connected to one sensing line SL, The sensing value for the driving transistor DRT can be obtained.

Therefore, in order to generate one sensing data by using two or more sensing values for the characteristic values of the driving transistor DRT, it is necessary that the number of times corresponding to a multiple of the number of the subpixels SP connected to one sensing line SL It is necessary to perform sensing to acquire two or more sensing values for the characteristic values of the driving transistor DRT included in each subpixel SP.

In the present embodiments, when there are two or more subpixels SP connected to the sensing line SL for sensing the characteristic value of the driving transistor DRT, the number of subpixels SP connected to one sensing line SL The characteristic value of the driving transistor DRT is sensed by the number of times corresponding to the multiple, and one sensing data is generated using the sensed value.

Therefore, even in the structure in which two or more sub-pixels SP are connected to one sensing line SL, one sensing data is generated using two or more sensing values for the characteristic values of the respective driving transistors DRT, The influence of the sensing value error due to the power supply ripple applied at the time of sensing the characteristic value of the DRT can be minimized.

9 shows another example of the driving transistor DRT characteristic value sensing method in the sub-pixel SP of the organic light emitting diode display 100 according to the present embodiments.

9, the sensing unit 310 senses a characteristic value of the driving transistor DRT in a separate sensing period a number of times corresponding to the number of gate lines GL arranged in the organic light emitting display panel 110 , It is possible to generate sensed data on the characteristic value of the driving transistor DRT by combining the sensed values.

That is, the sensing unit 310 acquires a sensing value corresponding to the number of gate lines GL disposed in the organic light emitting display panel 110 in a separate sensing period, and acquires a sensing value corresponding to the number of sensing lines The sensing value for the characteristic value of the driving transistor DRT included in the sub-pixel SP driven by one gate line GL may be extracted and one sensing data may be generated using the extracted sensing value.

For example, N sensing is performed in the organic light emitting display panel 110 in which the N gate lines GL are arranged, and the driving transistors (not shown) included in the subpixel SP driven by the gate line GL in the X column The sensing value for the characteristic value of the driving transistor DRT may be generated as the sensing data for the characteristic value of the driving transistor DRT.

Specifically, when N gate lines GL are arranged in the organic light emitting display panel 110, the sensing unit 310 performs sensing of the characteristic value of the driving transistor DRT N times in a separate sensing period .

The sensing unit 310 includes a driving transistor DRT included in the sub-pixel SP driven by the first gate line GL disposed in the organic light emitting display panel 110 among the sensed values in the first sensing period, The sensed value of the characteristic value of the sensor is extracted.

Among the values sensed in the second sensing period, a sensing value (pixel value) of a characteristic value of the driving transistor DRT included in the subpixel SP driven by the second gate line GL disposed in the organic light emitting display panel 110 .

Among the sensed values in the third sensing period, the characteristic value (?) Of the driving transistor (DRT) included in the subpixel (SP) driven by the third gate line (GL) (SP) driven by the N-th gate line GL disposed in the organic light emitting display panel 110 among the values sensed in the N-th sensing period by repeating the above- (DRT) included in the driving transistor DRT.

The sensing unit 310 may sense the characteristic value of the driving transistor DRT by sensing the driving transistor DRT included in the sub pixel SP driven by one of the gate lines GL extracted during each sensing period. The sensing data for the characteristic value of the driving transistor DRT is generated as the sensing value for the characteristic value of the driving transistor DRT. That is, the sensing data extracted during N sensing operations are combined to generate one sensing data.

As described above, by sensing only the sensing value of the characteristic value of the driving transistor DRT included in the sub-pixel SP driven by one gate line GL in each sensing period, So that the sensing value at which an error has occurred due to the power supply ripple can be excluded as much as possible from the sensing data.

That is, by extracting the sensing value for the characteristic value of the driving transistor DRT included in the sub-pixel SP driven by one gate line GL among the values sensed in one sensing period, (N-1) The sensing value of the characteristic value of the driving transistor DRT included in the sub-pixel SP driven by the gate line GL is excluded from the sensing data. In this process, the sensing value at which the error due to the power ripple occurs is So that the sensing data can be generated only by the sensing value not including the sensing data.

Another example is to perform sensing on the characteristic values of the driving transistor DRT by the number of times corresponding to the number of data lines DL arranged in the organic light emitting display panel 110, Only one sensing value for the characteristic value of the driving transistor DRT included in the subpixel SP driven by the data line DL of the column is extracted and the extracted sensing value is combined to obtain one It is also possible to generate sensing data.

For example, the sensing value of the characteristic value of the driving transistor DRT included in the sub-pixel SP driven by the first data line DL among the values sensing the characteristic value of the driving transistor DRT in the first sensing period Of the driving transistor DRT included in the subpixel SP driven by the second data line DL among the values obtained by sensing the characteristic value of the driving transistor DRT in the second sensing period And extracts the sensed value for the target.

In the same manner, the sensing of the characteristic value of the driving transistor DRT and the extraction of the sensing value are repeated, and during the sensing of the M number of times, the subpixel SP driven by any one of the data lines DL in each sensing period (DRT) included in the driving transistor DRT and generates one sensing data as the sensed sensing value.

Therefore, only the sensed value of the characteristic value of the driving transistor DRT included in the sub-pixel SP driven by one of the data lines DL sensed in the sensing period is extracted, and the remaining (M-1) The sensing value for the characteristic value of the driving transistor DRT included in the sub pixel SP driven by the data line DL is excluded from the sensing data so that the sensing value for which the error due to the power supply ripple occurs is excluded from the sensing data So that the influence of the error of the sensing value can be minimized and the reliability of the sensing data can be improved.

10 and 11 illustrate the driving method of the OLED display 100 according to the present embodiments.

10, the sensing unit 310 of the organic light emitting diode display 100 according to the exemplary embodiments of the present invention senses the characteristic value of the driving transistor DRT in a period during which the characteristic value of the driving transistor DRT is sensed S1000).

The sensing unit 310 senses a characteristic value of the driving transistor DRT in another sensing period (S1010).

The sensing unit 310 accumulates sensing values for the same driving transistor DRT sensed in a separate sensing period (S1020), and calculates an average value of the accumulated sensing values (S1030).

The sensing unit 310 may calculate an average value from two or more accumulated sensing values and may calculate an average value from the sensing values excluding the maximum value and the minimum value from three or more sensed values.

The sensing unit 310 generates one sensing data for a characteristic value of the corresponding driving transistor DRT as an average value of two or more sensing values sensed in a separate interval (S1040).

Accordingly, in generating the sensing data for the characteristic value of the driving transistor DRT, one sensing data for the characteristic value of the driving transistor DRT is generated by an average value of two or more sensing values sensed in a separate sensing period, It is possible to minimize the influence of the error of the sensing value caused by the ripple of the power supply applied to the sensing data when the characteristic value of the transistor DRT is sensed.

11, the sensing unit 310 of the organic light emitting diode display 100 according to the present exemplary embodiment includes sub pixels SP of the organic light emitting display panel 110 in which N gate lines GL are disposed, The characteristic value of the driving transistor DRT may be sensed N times and one sensed data may be generated using the sensed value of N times.

The sensing unit 310 sets X to 1 in the first sensing period (S1100) and performs sensing on the characteristic value of the driving transistor DRT (S1110).

The sensing value for the characteristic value of the driving transistor DRT included in the sub-pixel SP driven by the first gate line GL among the sensed values of the characteristic values of the driving transistor DRT sensed in the first sensing period is (S1120).

The sensing unit 310 increases X by 1 in step S1130 and compares X with N that is the number of the gate lines GL disposed in the organic light emitting display panel 110 in step S1140. The above-described process is repeatedly performed.

That is, in the second sensing period, the sensing value of the characteristic value of the driving transistor DRT included in the sub-pixel SP driven by the second gate line GL among the sensed values of the driving transistor DRT, The driving transistor DRT included in the subpixel SP driven by the Nth gate line GL among the sensed values for the characteristic values of the driving transistor DRT in the Nth sensing period, ) Is extracted.

The sensing unit 310 generates sensing data for the characteristic value of the driving transistor DRT at a sensing value extracted at each sensing period when the sensing of N times is completed (S1150).

Therefore, only the sensing value of the driving transistor DRT included in the sub-pixel SP driven by one of the gate lines GL in each sensing period is extracted and the remaining (N-1) The sensing value for the characteristic value of the driving transistor DRT included in the sub-pixel SP driven by the driving transistor DR is excluded from the sensing data so that the sensing value at which an error caused by the power supply ripple occurs can be excluded from the sensing data.

According to the embodiments, the average value of two or more sensing values sensed in a separate sensing period may be generated as sensing data, or the sensing data may be supplied to the subpixel SP driven by one of the gate lines GL in one sensing period The sensing data is generated by extracting only the sensing value of the driving transistor DRT included in the driving transistor DRT so that sensing data minimizing the influence of the sensing error due to the ripple of the power supplied at the time of sensing the characteristic value of the driving transistor DRT is generated .

This prevents the erroneous compensation due to the error of the sensing value of the driving transistor DRT from being performed and prevents a screen defect such as a horizontal line shape due to erroneous compensation for the characteristic value of the driving transistor DRT from occurring.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention as defined by the appended claims. The embodiments of the present invention are not intended to limit the scope of the present invention but to limit the scope of the present invention.

100: organic light emitting display device 110: organic light emitting display panel
120: gate driver 130: data driver
140: timing controller 310: sensing unit
320: compensation unit 330: memory

Claims (12)

An organic light emitting display in which a plurality of subpixels including an organic light emitting diode and a driving transistor for driving the organic light emitting diode are arranged so that N (N? 2) gate lines and M (M? 2) Display panel;
A gate driver for driving the N gate lines;
A data driver for driving the M data lines; And
A sensing unit for sensing one characteristic value of the driving transistor by the gate line and generating one sensing data for a characteristic value of the driving transistor by using two or more sensing values sensed for the same driving transistor in a separate sensing period,
And an organic light emitting diode (OLED).
The method according to claim 1,
The sensing unit includes:
And generates sensing data for a characteristic value of the driving transistor by an average value of two or more sensing values for a characteristic value of the driving transistor.
The method according to claim 1,
The sensing unit includes:
Wherein the sensing data for the characteristic value of the driving transistor is generated by an average value of the sensing values excluding the maximum value and the minimum value at three or more sensing values of the characteristic values of the driving transistor.
The method according to claim 1,
The sensing unit includes:
Sensing a characteristic value of the driving transistor by a number corresponding to a multiple of a ratio of the number of subpixels and the number of sensing lines for sensing a characteristic value of the driving transistor, and using one of the sensed values, And generates sensing data.
The method according to claim 1,
The sensing unit includes:
The characteristic value of the driving transistor is sensed N times in a separate sensing period, and the characteristic value of the driving transistor is multiplied by the Xth sensing value of the driving transistor included in the subpixel driven by the gate line of X (1? X? N) And generates sensing data for the organic light emitting display device.
6. The method of claim 5,
The sensing unit includes:
The sensing value of the driving transistor arranged in the sub-pixel driven by the X-th gate line at the X-th sensing value is sensed while sensing the characteristic value of the driving transistor in the sensing period N, And generates sensing data.
The method according to claim 1,
The sensing unit includes:
The characteristic value of the driving transistor is sensed M times in a separate sensing period, and the characteristic value of the driving transistor is set to the Y-th sensing value of the driving transistor included in the subpixel driven by the data line of Y (1? Y? M) And generates sensing data for the organic light emitting display device.
The method according to claim 1,
And a compensation unit for generating a compensation value for a characteristic value of the driving transistor based on sensing data generated based on two or more sensing values obtained by sensing the characteristic value of the driving transistor in a separate sensing period.
An organic light emitting diode (OLED) display device including an organic light emitting diode (OLED) display panel in which a plurality of gate lines and a plurality of data lines are crossed and a plurality of subpixels including an organic light emitting diode and a driving transistor In the method,
Sensing characteristic values of the driving transistor sequentially for each gate line; And
Generating one sensing data for a characteristic value of the driving transistor by using two or more sensed values sensed in a separate sensing period for the same driving transistor
And a driving method of the organic light emitting display device.
10. The method of claim 9,
Wherein the step of generating one sensing data for a characteristic value of the driving transistor comprises:
And generating sensing data for a characteristic value of the driving transistor by an average value of two or more sensing values obtained by sensing the characteristic value of the driving transistor in a separate sensing period.
10. The method of claim 9,
Wherein the step of generating one sensing data for a characteristic value of the driving transistor comprises:
The sensing data for the characteristic value of the driving transistor to the Xth sensing value of the driving transistor included in the subpixel driven by the gate line of the X column among the values obtained by sensing the characteristic value of the driving transistor for the number of times corresponding to the number of the gate lines The driving method comprising the steps of:
10. The method of claim 9,
Wherein the step of generating one sensing data for a characteristic value of the driving transistor comprises:
A sensing value for a characteristic value of the driving transistor to a Y-th sensing value of a driving transistor included in a sub-pixel driven by a data line of a Y-th row among values obtained by sensing the characteristic value of the driving transistor by a number corresponding to the number of data lines, A method of driving an organic light emitting display device that generates data.

Images