KR102526241B1 - Controller, organic light emitting display device and the method for driving the same - Google Patents

Abstract

The present embodiments relate to a controller, an organic light emitting display device, and a method for driving the same, and more particularly, during a driving period of sensing a driving transistor for sensing a characteristic value of a driving transistor in a target subpixel to be sensed, an organic light emitting display device in a target subpixel to be sensed. The sensing driving of the driving transistor is performed using the sensing driving data voltage set based on the threshold voltage of the light emitting diode. Accordingly, it is possible to more accurately sense the characteristic values of the driving transistor without the influence of the organic light emitting diode without arbitrarily adjusting the base voltage applied to the organic light emitting diode.

Description

Controller, organic light emitting display device and its driving method

The present embodiments relate to a controller, an organic light emitting display device, and a driving method thereof.

Recently, an organic light emitting display device that has been in the limelight as a display device uses an organic light emitting diode (OLED) that emits light by itself, and has advantages such as fast response speed, luminous efficiency, luminance, and viewing angle.

Such an organic light emitting display device arranges subpixels including organic light emitting diodes and driving transistors for driving them in a matrix form, and controls brightness of subpixels selected by a scan signal according to grayscale of data.

Meanwhile, as the driving time of each subpixel increases, intrinsic characteristic values such as a threshold voltage and mobility of a driving transistor in each subpixel may change.

A change in the characteristic value of the driving transistor causes a change in luminance of a corresponding subpixel.

In addition, since driving time between subpixels may be different from each other, variation in characteristic values between driving transistors may occur.

Differences in characteristic values between driving transistors may cause luminance deviations between subpixels, thereby deteriorating image quality of the organic light emitting display panel.

Accordingly, technologies for compensating for characteristic value deviations between driving transistors by sensing characteristic values of driving transistors are being developed.

Meanwhile, when sensing the characteristic value of the driving transistor, an accurate sensing value can be obtained only when the organic light emitting diode is accurately turned off.

However, when the conventional sensing and compensation technology is applied, there has been a problem in that the characteristic value of the driving transistor cannot be accurately sensed due to the influence of the organic light emitting diode.

An object of the present embodiments is to provide a controller, an organic light emitting display device, and a driving method capable of accurately sensing a characteristic value of a driving transistor without the influence of an organic light emitting diode.

Another object of the present embodiments is to accurately sense a characteristic value of a driving transistor without the influence of the organic light emitting diode without arbitrarily adjusting the base voltage applied to the second electrode among the first and second electrodes of the organic light emitting diode. It is an object of the present invention to provide a controller, an organic light emitting display device, and a driving method thereof.

Another object of the present embodiments is to reflect the characteristics of the organic light emitting diode in each sub-pixel and perform a sensing drive to sense the characteristic value of the driving transistor, so that the characteristic value of the driving transistor can be more accurately sensed. It is to provide a light emitting display device and a driving method thereof.

In one aspect, in the present embodiments, a plurality of subpixels defined by a plurality of data lines and a plurality of gate lines are arranged, and an organic light emitting diode and a driving transistor for driving the organic light emitting diode are disposed in each subpixel. It is possible to provide an organic light emitting display device including a light emitting display panel, a data driver driving a plurality of data lines, a gate driver driving a plurality of gate lines, and a controller controlling the data driver and the gate driver.

In such an organic light emitting display device, the data driver, during a driving transistor sensing driving period for sensing the characteristic values of the driving transistors in the sensing target subpixel, sets the data for sensing and driving based on the threshold voltage of the organic light emitting diode in the sensing target subpixel. voltage can be output.

In another aspect, an organic light emitting display panel in which a plurality of subpixels defined by a plurality of data lines and a plurality of gate lines are arranged, and an organic light emitting diode and a driving transistor for driving the organic light emitting diode are disposed in each subpixel; A method of driving an organic light emitting display device including a data driver driving a plurality of data lines, a gate driver driving a plurality of gate lines, and a controller controlling the data driver and the gate driver may be provided.

A method of driving an organic light emitting display device includes calculating a data voltage for sensing and driving, and performing sensing and driving of a driving transistor for sensing a characteristic value of a driving transistor in a subpixel to be sensed using the data voltage for sensing and driving. and calculating and storing a compensation value for a characteristic value of a driving transistor in a subpixel to be sensed based on a sensing value obtained through sensing driving of the driving transistor.

The step of performing sensing driving of the driving transistor includes applying a data voltage for sensing driving to a first node of the driving transistor and applying a reference voltage to a second node of the driving transistor, and floating the second node of the driving transistor. The method may include increasing a voltage of a second node of the driving transistor and sensing a voltage of a second node of the driving transistor or a sensing line electrically connected to the second node of the driving transistor.

In the above-described step of calculating the data voltage for sensing and driving, the data voltage for sensing and driving may be calculated based on the threshold voltage of the organic light emitting diode in the subpixel to be sensed.

In another aspect, the present embodiments provide a sensing drive data generator for generating sensing drive data necessary for driving a sensing drive for sensing a characteristic value of a drive transistor in a target subpixel to be sensed, and outputting the sensing drive data. A controller for an organic light emitting display device may include a sensing driving data output unit configured to calculate and output a compensation value for a characteristic value of a driving transistor in a subpixel to be sensed based on the stored or received sensing data. .

In such a controller, the sensing driving data generating unit may generate sensing driving data based on a threshold voltage of an organic light emitting diode within a sensing target subpixel.

According to the present embodiments as described above, it is possible to provide a controller, an organic light emitting display device, and a driving method capable of accurately sensing characteristic values of driving transistors without the influence of organic light emitting diodes.

In addition, according to the present embodiments, the characteristic value of the driving transistor can be accurately sensed without the influence of the organic light emitting diode without arbitrarily adjusting the base voltage applied to the second electrode of the first electrode and the second electrode of the organic light emitting diode. A controller, an organic light emitting display device, and a driving method thereof may be provided.

In addition, according to the present embodiments, by reflecting the characteristics of the organic light emitting diode in each subpixel and performing a sensing drive for sensing the characteristic value of the driving transistor, a controller that can more accurately sense the characteristic value of the driving transistor; A light emitting display device and a driving method thereof may be provided.

1 is a system configuration diagram of an organic light emitting display device according to the present embodiments.
2 is an exemplary diagram of a sub-pixel structure of an organic light emitting display device according to the present embodiments.
3 is another exemplary diagram of a sub-pixel structure of an organic light emitting display device according to the present embodiments.
4 is an exemplary diagram of a compensation circuit of an organic light emitting display device according to the present embodiments.
FIG. 5 is a diagram for explaining a threshold voltage sensing driving method during sensing driving of a driving transistor of an organic light emitting display device according to the exemplary embodiments.
6 is a diagram for explaining a mobility sensing driving method among driving transistor sensing driving of an organic light emitting display device according to the present exemplary embodiments.
7 to 9 illustrate a method of improving sensing accuracy for characteristic values of a driving transistor by minimizing the influence of the organic light emitting diode by increasing the base voltage in the sensing driving period of the driving transistor of the organic light emitting display device according to the present embodiments. they are drawings
10 illustrates a driving method capable of improving sensing accuracy for characteristic values of a driving transistor while minimizing an influence of an organic light emitting diode without an increase in base voltage in a driving transistor sensing driving period in an organic light emitting display device according to the present embodiments. These are drawings for explanation.
11 illustrates a driving method capable of improving sensing accuracy for characteristic values of a driving transistor while minimizing the influence of an organic light emitting diode without an increase in base voltage in a driving transistor sensing driving period in an organic light emitting display device according to the present embodiments. It is a flow chart for
12 illustrates a voltage change of a second node of a driving transistor in a driving transistor sensing driving period and a driving transistor sensing driving period for sensing a characteristic value of a driving transistor without raising a base voltage in an organic light emitting display device according to the present embodiments. It is a diagram for explaining the data voltage for sensing driving of .
13 illustrates a driving method capable of improving sensing accuracy for characteristic values of a driving transistor while minimizing an influence of an organic light emitting diode without an increase in base voltage in a driving transistor sensing driving period in an organic light emitting display device according to the present embodiments. Another flow chart for
14 is a flowchart of an organic light emitting diode sensing driving method for sensing a threshold voltage of the organic light emitting diode in the organic light emitting display device according to the present embodiments.
15 is a diagram illustrating circuit states at each stage in the organic light emitting diode sensing driving method for sensing the threshold voltage of the organic light emitting diode in the organic light emitting display device according to the present embodiments.
16 is a diagram illustrating a voltage change of a sensing line in an organic light emitting diode sensing driving period for sensing a threshold voltage of the organic light emitting diode in the organic light emitting display device according to the present embodiments.
17 is another flowchart illustrating an organic light emitting diode sensing driving method for sensing a threshold voltage of the organic light emitting diode in the organic light emitting display device according to the present embodiments.
18 is a diagram illustrating voltage changes of main signals and sensing lines in an organic light emitting diode sensing driving period for sensing a threshold voltage of the organic light emitting diode in the organic light emitting display device according to the present embodiments.
19 is a block diagram of a controller according to the present embodiments.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the present invention are described in detail below with reference to exemplary drawings. In adding reference numerals to components of each drawing, the same components may have the same numerals as much as possible even if they are displayed on different drawings. In addition, in describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description may be omitted.

Also, terms such as first, second, A, B, (a), and (b) may be used in describing the components of the present invention. These terms are only used to distinguish the component from other components, and the nature, sequence, order, or number of the corresponding component is not limited by the term. When an element is described as being “connected,” “coupled to,” or “connected” to another element, that element is or may be directly connected to that other element, but intervenes between each element. It will be understood that may be "interposed", or each component may be "connected", "coupled" or "connected" through other components.

1 is a system configuration diagram of an organic light emitting display device 100 according to the present embodiments.

Referring to FIG. 1 , in an organic light emitting display device 100 according to the present embodiments, a plurality of data lines DL and a plurality of gate lines GL are disposed, and a plurality of sub pixels (SP) The arrayed organic light emitting display panel 110, a data driver 120 driving a plurality of data lines DL, a gate driver 130 driving a plurality of gate lines GL, and a data driver 120 ) and the controller 140 controlling the gate driver 130.

The controller 140 controls the data driver 120 and the gate driver 130 by supplying various control signals to the data driver 120 and the gate driver 130 .

The controller 140 starts scanning according to the timing implemented in each frame, converts input image data input from the outside to suit the data signal format used by the data driver 120, and outputs the converted image data. , data drive is controlled at an appropriate time according to the scan.

The controller 140 may be a timing controller used in a typical display technology or a control device that further performs other control functions including a timing controller.

The data driver 120 drives the plurality of data lines DL by supplying data voltages to the plurality of data lines DL. Here, the data driver 120 is also referred to as a 'source driver'.

The data driver 120 may include at least one source driver integrated circuit (SDIC) to drive a plurality of data lines.

The gate driver 130 sequentially drives the plurality of gate lines GL by sequentially supplying scan signals to the plurality of gate lines GL. Here, the gate driver 130 is also referred to as a 'scan driver'.

The gate driver 130 may include at least one gate driver integrated circuit (GDIC).

The gate driver 130 sequentially supplies scan signals of an on voltage or an off voltage to the plurality of gate lines GL under the control of the controller 140 .

When a specific gate line is opened by the gate driver 130, the data driver 120 converts the image data received from the controller 140 into analog data voltages and supplies them to a plurality of data lines DL.

The data driver 120 is located on only one side (eg, upper or lower side) of the organic light emitting display panel 110 in FIG. : upper side and lower side) may be located both.

The gate driver 130 is located on only one side (eg, the left or right side) of the organic light emitting display panel 110 in FIG. Example: left and right) may be located on both sides.

The above-described controller 140 includes various types of input image data, including a vertical synchronization signal (Vsync), a horizontal synchronization signal (Hsync), an input data enable (DE) signal, a clock signal (CLK), and the like. Receive timing signals from outside (e.g. host system).

The controller 140 receives timing signals such as a vertical sync signal (Vsync), a horizontal sync signal (Hsync), an input DE signal, and a clock signal in order to control the data driver 120 and the gate driver 130, Various control signals are generated and output to the data driver 120 and the gate driver 130.

For example, in order to control the gate driver 130, the controller 140 includes a gate start pulse (GSP), a gate shift clock (GSC), and a gate output enable signal (GOE: It outputs various gate control signals (GCS: Gate Control Signal) including 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 130 . The gate shift clock (GSC) is a clock signal commonly input to one or more gate driver integrated circuits and controls shift timing of scan signals (gate pulses). The gate output enable signal GOE specifies timing information of one or more gate driver integrated circuits.

In addition, the controller 140, in order to control the data driver 120, a source start pulse (SSP: Source Start Pulse), a source sampling clock (SSC: Source Sampling Clock), a source output enable signal (SOE: Source Output It outputs various data control signals (DCS) including Enable) and the like.

Here, the source start pulse SSP controls data sampling start timing of one or more source driver integrated circuits constituting the data driver 120 . The source sampling clock (SSC) is a clock signal that controls sampling timing of data in each source driver integrated circuit. The source output enable signal SOE controls output timing of the data driver 120 .

The data driver 120 may include at least one source driver integrated circuit (SDIC) to drive a plurality of data lines.

Each source driver integrated circuit (SDIC) is attached 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. It may be connected to, directly disposed on the organic light emitting display panel 110, or may be integrated and disposed on the organic light emitting display panel 110 in some cases. In addition, each source driver integrated circuit (SDIC) may be implemented in a Chip On Film (COF) method mounted on a film connected to the organic light emitting display panel 110 .

Each source driver integrated circuit (SDIC) may include a shift register, a latch circuit, a digital to analog converter (DAC), an output buffer, and the like.

In some cases, each source driver integrated circuit (SDIC) may further include an analog to digital converter (ADC).

The gate driver 130 may include at least one gate driver integrated circuit (GDIC).

Each gate driver integrated circuit (GDIC) is 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, or is connected to a gate in panel (GIP) method. ) type and directly disposed on the organic light emitting display panel 110, or may be integrated and disposed on the organic light emitting display panel 110 in some cases. In addition, each gate driver integrated circuit (GDIC) may be implemented in a chip on film (COF) method mounted on a film connected to the organic light emitting display panel 110 .

Each gate driver integrated circuit (GDIC) may include a shift register, a level shifter, and the like.

The organic light emitting display device 100 according to the present embodiments includes at least one source printed circuit board (S-PCB) required for circuit connection to at least one source driver integrated circuit (SDIC) and It may include a control printed circuit board (C-PCB) for mounting control parts and various electric devices.

At least one source driver integrated circuit (SDIC) may be mounted on the at least one source printed circuit board (S-PCB), or a film having at least one source driver integrated circuit (SDIC) mounted may be connected.

On the control printed circuit board (C-PCB), the controller 140 for controlling operations of the data driver 120 and the gate driver 130, the organic light emitting display panel 110, the data driver 120, and the gate driver A power controller that supplies various voltages or currents to 130 or the like or controls various voltages or currents to be supplied may be mounted.

The at least one source printed circuit board (S-PCB) and the control printed circuit board (C-PCB) may be circuitically connected through at least one connecting member.

Here, the connecting member may be a flexible printed circuit (FPC) or a flexible flat cable (FFC).

At least one source printed circuit board (S-PCB) and one control printed circuit board (C-PCB) may be integrated into one printed circuit board.

Each subpixel SP disposed on the organic light emitting display panel 110 may include a circuit element such as a transistor.

For example, each sub-pixel SP is composed of organic light emitting diodes (OLEDs) and circuit elements such as driving transistors for driving them.

The type and number of circuit elements constituting each sub-pixel SP may be variously determined according to a provided function and a design method.

2 is an exemplary diagram of a sub-pixel structure of the organic light emitting display device 100 according to the present embodiments.

Referring to FIG. 2 , in the organic light emitting display device 100 according to the present embodiments, each subpixel basically drives an organic light emitting diode (OLED) and an organic light emitting diode (OLED). a driving transistor (DRT) for transmitting a data voltage to a first node (N1) corresponding to the gate node of the driving transistor (DRT), and data corresponding to the image signal voltage. It may be configured to include a storage capacitor (Cst: Storage Capacitor) that maintains the voltage or a voltage corresponding thereto for one frame time.

An organic light emitting diode (OLED) may include a first electrode (eg, an anode electrode), an organic layer, and a second electrode (eg, a cathode electrode).

The driving transistor DRT drives the organic light emitting diode (OLED) by supplying a driving current to the organic light emitting diode (OLED).

In the driving transistor DRT, the first node N1 may be electrically connected to the source node or the drain node of the first transistor T1 and may be a gate node. The second node N2 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 third node N3 may be electrically connected to a driving voltage line (DVL) that supplies the driving voltage EVDD, and may be a drain node or a source node.

The first transistor T1 is electrically connected between the data line DL and the first node N1 of the driving transistor DRT, and is controlled by receiving the first scan signal SCAN1 to the gate node through the gate line. It can be.

The first transistor T1 is turned on by the first scan signal SCAN1 to transfer the data voltage Vdata supplied from the data line DL to the first node N1 of the driving transistor DRT. can

The driving transistor DRT and the first transistor T1 may be implemented as n-type or p-type.

The storage capacitor Cst may be electrically connected between the second node N2 and the first node N1 of the driving transistor DRT.

The storage capacitor Cst is not a parasitic capacitor (eg, Cgs or Cgd) that is an internal capacitor existing between the second node N2 and the first node N1 of the driving transistor DRT, but It is an external capacitor intentionally designed outside the driving transistor (DRT).

Meanwhile, in the case of the organic light emitting display device 100 according to the present exemplary embodiments, as the driving time of each subpixel SP is increased, circuit elements such as an organic light emitting diode (OLED) and a driving transistor (DRT) Degradation may proceed.

Accordingly, inherent characteristic values (eg, threshold voltage, mobility, etc.) of circuit elements such as organic light emitting diodes (OLEDs) and driving transistors (DRTs) may change.

A change in the characteristic value of such a circuit element may cause a change in luminance of a corresponding subpixel.

In addition, the degree of change in characteristic values between circuit elements may be different depending on the degree of deterioration of each circuit element.

Characteristic value deviations between circuit elements, which occur as described above, may cause luminance deviations between subpixels, resulting in luminance non-uniformity of the organic light emitting display panel 110 .

Here, the characteristic value of the circuit element (hereinafter, also referred to as “sub-pixel characteristic value”) may include, for example, the threshold voltage and mobility of the driving transistor DRT, and in some cases, the organic light emitting diode (OLED) may include a threshold voltage of

The organic light emitting display device 100 according to the present embodiments is driven using a sensing function for sensing characteristic values or changes thereof of circuit elements such as a driving transistor (DRT) and an organic light emitting diode (OLED), and a sensing result. A compensation function for compensating for characteristic value deviations between circuit elements such as a transistor (DRT) and an organic light emitting diode (OLED) may be provided.

The organic light emitting display device 100 according to the present embodiments senses characteristic values or changes thereof of circuit elements such as a driving transistor (DRT) and an organic light emitting diode (OLED), and compensates for variation in characteristic values. It may include a pixel structure and a compensation circuit including sensing and compensation components.

3 is another exemplary view of a sub-pixel structure of the organic light emitting display device 100 according to the present embodiments.

Referring to FIG. 3 , each subpixel disposed on the organic light emitting display panel 110 according to the present embodiments includes, for example, an organic light emitting diode (OLED), a driving transistor (DRT), a first transistor (T1), and In addition to the storage capacitor Cst, a second transistor T2 may be further included.

Referring to FIG. 3 , the second transistor T2 is electrically connected between the second node N2 of the driving transistor DRT and a sensing line (SL) supplying a reference voltage (Vref). and can be controlled by receiving the second scan signal SCAN2, which is a kind of scan signal, to the gate node.

The second transistor T2 is turned on by the second scan signal SCAN2 and applies the reference voltage Vref supplied through the sensing line SL to the second node N2 of the driving transistor DRT. it does

Also, the second transistor T2 may be used as one of the voltage sensing paths for the second node N2 of the driving transistor DRT.

Meanwhile, when the gate node of the first transistor T1 and the gate node of the second transistor T2 are connected to different gate lines, the first scan signal SCAN1 and the second scan signal SCAN2 may be separate scan signals. can

When the gate node of the first transistor T1 and the gate node of the second transistor T2 are connected to the same gate line, the first scan signal SCAN1 and the second scan signal SCAN2 may be the same scan signal.

4 is an exemplary diagram of a compensation circuit of the organic light emitting display device 100 according to the present embodiments.

Referring to FIG. 4 , in the organic light emitting display device 100 according to the present embodiments, the voltage of the sensing line SL is sensed to sense subpixel characteristic values (driving transistor characteristic values, organic light emitting diode characteristic values) or changes thereof. At least one analog-to-digital converter (ADC: Analog to Digital Converter, 410) for sensing and converting the sensed voltage into a sensing value corresponding to a digital value to output sensing data including the sensing value, and to store the sensing data It may include a memory 420 and a compensating unit 430 that performs a compensation process for compensating deviations between subpixel characteristic values (driving transistor characteristic values and organic light emitting diode characteristic values) using sensing data.

Each analog-to-digital converter 410 may be included inside the source driver integrated circuit (SDIC), and in some cases may be included outside the source driver integrated circuit (SDIC).

The compensating unit 430 may be included inside the controller 140 and, in some cases, may be included outside the controller 140 .

The organic light emitting display device 100 according to the present exemplary embodiments may further include an initialization switch SPRE and a sampling switch SAM to control sensing driving.

The initialization switch SPRE may be electrically connected between the sensing line SL and a reference voltage supply node (not shown).

When the initialization switch SPRE is turned on, the reference voltage Vref may be supplied to the sensing line SL. At this time, when the second transistor T2 is turned on, the reference voltage Vref may be applied to the second node N2 of the driving transistor DRT.

The sampling switch SAM may be electrically connected between the sensing line SL and the analog-to-digital converter 410 .

When the sampling switch SAM is turned on, the analog-to-digital converter 410 may sense the voltage of the sensing line SL.

Meanwhile, the voltage of the sensing line SL may be the same as the voltage charged in the line capacitor formed on the sensing line SL.

Also, when the second transistor T2 is turned on, the voltage of the sensing line SL may be equal to the voltage of the second node N2 of the driving transistor DRT.

For example, one sensing line SL may be disposed in each subpixel column, or one sensing line SL may be disposed in each of two or more subpixel columns.

For example, when one pixel is composed of four subpixels (red subpixel, white subpixel, green subpixel, and blue subpixel), the sensing line SL has four subpixel columns (red subpixel column, Each pixel column including a white subpixel column, a green subpixel column, and a blue subpixel column) may be disposed one by one.

The voltage sensed by the analog-to-digital converter 410 is a voltage value (Vdata-Vth or Vdata-ΔVth) for sensing the threshold voltage (Vth) of the driving transistor (DRT) or its change (ΔVth), depending on the type of sensing drive. ) or a voltage value for sensing the mobility of the driving transistor DRT.

Below, threshold voltage sensing driving and mobility sensing driving of the driving transistor DRT will be briefly described.

FIG. 5 is a diagram for explaining a threshold voltage sensing driving method during sensing driving of the driving transistor of the organic light emitting display device 100 according to the present exemplary embodiments.

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 generate a threshold voltage sensing driving data voltage Vdata and a reference voltage Vref. is initialized with

Thereafter, the initialization switch SPRE is turned off so that the second node N2 of the driving transistor DRT is floating.

Accordingly, the voltage of the second node N2 of the driving transistor DRT rises.

The voltage of the second node N2 of the driving transistor DRT rises, then the range of the rise gradually decreases, eventually reaching saturation.

The saturated voltage of the second node N2 of the driving transistor DRT may correspond to a difference between the data voltage Vdata and the threshold voltage Vth or a difference between the data voltage Vdata and the change in the threshold voltage ΔVth. .

When the voltage of the second node N2 of the driving transistor DRT is saturated, the analog-to-digital converter 410 senses the saturated voltage of the second node N2 of the driving transistor DRT.

The voltage (Vsen) sensed by the analog-to-digital converter 410 is a voltage obtained by subtracting the threshold voltage (Vth) from the data voltage (Vdata) (Vdata-Vth) or a voltage obtained by subtracting the threshold voltage change (ΔVth) from the data voltage (Vdata). (Vdata-ΔVth).

FIG. 6 is a diagram for explaining a mobility sensing driving method among driving transistor sensing driving of the organic light emitting display device 100 according to the present exemplary embodiments.

When the driving transistor DRT is driven for mobility sensing, the first node N1 and the second node N2 of the driving transistor DRT generate a data voltage Vdata and a reference voltage Vref for mobility sensing driving, respectively. is initialized with

Thereafter, the initialization switch SPRE is turned off and the second node N2 of the driving transistor DRT is floated. At this time, the first scan signal SCAN1 is changed to a turn-off level voltage, so that the first node N1 of the driving transistor DRT may also float.

Accordingly, the voltage of the second node N2 of the driving transistor DRT starts to rise.

A voltage rising speed of the second node N2 of the driving transistor DRT may vary according to current capability, that is, mobility of the driving transistor DRT. Here, the voltage rising rate of the second node N2 of the driving transistor DRT corresponds to the amount of change ΔV of the voltage rising value for a certain period of time.

That is, the higher the current capability (mobility) of the driving transistor DRT, the steeper the voltage at the second node N2 of the driving transistor DRT rises.

After the voltage of the second node N2 of the driving transistor DRT rises for a predetermined period of time, the sampling switch SAM is turned on, and the analog-to-digital converter 410 outputs the voltage of the sensing line SL. By sensing , the increased voltage of the second node N2 of the driving transistor DRT may be sensed.

According to the threshold voltage sensing driving method or the mobility sensing driving method described above with reference to FIGS. 5 and 6 , the analog-to-digital converter 410 corresponds to the voltage Vsen sensed for threshold voltage sensing or mobility sensing as a digital value. The sensing value to be converted is converted, and sensing data including the converted sensing value is generated and output.

Sensing data output from the analog-to-digital converter 410 may be stored in the memory 420 or provided to the compensator 430 .

Compensation unit 430 is based on the sensing data stored in the memory 420 or provided from the analog-to-digital converter 410, the characteristic value (eg, threshold voltage, mobility) of the driving transistor (DRT) in the corresponding sub-pixel or its change (eg, threshold voltage) : threshold voltage change, mobility change), and a characteristic value compensation process for the driving transistor (DRT) may be performed.

Here, the change in the characteristic value of the driving transistor DRT may mean a change in current sensing data based on previous sensing data or a change in current sensing data based on reference sensing data.

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

The threshold voltage compensation process calculates a compensation value to compensate for the threshold voltage or threshold voltage deviation (threshold voltage change), stores the calculated compensation value in the memory 420, or converts the corresponding image data (Data) into the calculated compensation value. It may include processing to change the .

In the mobility compensation process, a compensation value for compensating for mobility or mobility deviation (mobility change) is calculated, the calculated compensation value is stored in the memory 420, or the corresponding image data (Data) is stored as the calculated compensation value. It may include processing to change the .

The compensator 430 may change the image data (Data) through a threshold voltage compensation process or a mobility compensation process and supply the changed data to a corresponding source driver integrated circuit (SDIC) in the data driver 120 .

Accordingly, the corresponding source driver integrated circuit (SDIC) converts the data changed in the compensation unit 430 into a data voltage through a digital to analog converter (DAC) 440 and supplies it to the corresponding subpixel, Pixel characteristic value compensation (threshold voltage compensation, mobility compensation) is actually performed.

As such sub-pixel characteristic value compensation is performed, the luminance deviation between sub-pixels is reduced or prevented, thereby improving image quality.

7 to 9 show the driving transistor DRT by minimizing the influence of the organic light emitting diode (OLED) by increasing the base voltage EVSS in the driving transistor sensing driving period of the organic light emitting display device 100 according to the present embodiments. These are drawings showing a method of improving the sensing accuracy for the characteristic value of .

Referring to FIG. 7 , during the driving period for sensing the characteristic values (threshold voltage, mobility) of the driving transistor DRT, the influence of the organic light emitting diode (OLED) must be minimized to determine the characteristic values of the driving transistor DRT. (threshold voltage, mobility) can be accurately sensed.

Therefore, referring to FIG. 7 , in order to minimize the influence of the organic light emitting diode (OLED) during the driving transistor sensing driving period, that is, to prevent current from flowing to the organic light emitting diode (OLED), the organic light emitting diode (OLED) is controlled. The base voltage (EVSS) applied to the two electrodes (eg, the cathode electrode) may be increased.

Referring to FIG. 8 showing the change in voltage of the second node N2 of the driving transistor DRT in the driving transistor sensing driving period for sensing the threshold voltage of the driving transistor DRT, at this time, the driving transistor DRT is increased in the sensing driving period. The true base voltage EVSS may be higher than the sensing driving data voltage Vdata applied to the first node N1 of the driving transistor DRT. Here, the data voltage Vdata for sensing driving may be a data voltage for threshold voltage sensing driving or a data voltage for mobility sensing driving.

Accordingly, the characteristic value of the driving transistor DRT can be accurately sensed without being affected by the organic light emitting diode OLED.

As described above, in order to improve sensing accuracy, the driving transistor sensing driving period and other periods are distinguished, and the base voltage EVSS corresponding to the ground voltage (GND) is applied to the organic light emitting diode in a period other than the driving transistor sensing driving period. The base voltage EVSS of a voltage value (for example, a voltage value higher than the data voltage for sensing driving) that is applied to the second electrode of the (OLED) and can turn off the organic light emitting diode (OLED) in the driving transistor sensing driving period. ) to the second electrode of the organic light emitting diode (OLED), the organic light emitting display device 100 should further include a base voltage control circuit 1000 as shown in FIG. 10 .

Due to this, a problem of increasing circuit component cost may occur.

On the other hand, since the characteristics of the organic light emitting diode (OLED) in each subpixel (SP) are not reflected during driving by sensing the driving transistor, there is also a problem in that the sensing accuracy of the characteristic value of the driving transistor (DRT) is lowered.

Accordingly, the present embodiments can accurately sense the characteristic value of the driving transistor DRT by removing the influence of the organic light emitting diode OLED without changing the base voltage EVSS in the driving transistor sensing driving period, and furthermore, It is possible to provide a driving method capable of more accurately sensing the characteristic value of the driving transistor DRT by reflecting the characteristic of the organic light emitting diode (OLED) in each subpixel (SP) in the driving transistor sensing driving period.

10 is a diagram of the driving transistor DRT while minimizing the influence of the organic light emitting diode OLED without increasing the base voltage EVSS in the driving transistor sensing driving period in the organic light emitting display device 100 according to the present embodiments. These drawings are for explaining a driving method capable of improving sensing accuracy for characteristic values.

Referring to FIG. 10 , the organic light emitting display device 100 according to the present exemplary embodiments minimizes the effect of the organic light emitting diode (OLED) without increasing the base voltage EVSS in the driving transistor sensing driving period, and the driving transistor ( In order to sense the characteristic value of the DRT, the base voltage EVSS is maintained as the ground voltage GND, and instead, the organic light emitting diode OLED is not turned on. The threshold voltage Vth_OLED of the organic light emitting diode OLED ), the sensing drive data voltage Vdata is adjusted.

For example, the organic light emitting display device 100 according to the present embodiments applies the sensing driving data voltage Vdata to the organic light emitting diode (OLED) so that the organic light emitting diode (OLED) is not turned on in the driving transistor sensing driving period. It can be set lower than the threshold voltage (Vth_OLED) of (OLED).

In addition, the organic light emitting display device 100 according to the present embodiments reflects the characteristics of the organic light emitting diode (OLED) in each subpixel (SP) in the driving transistor sensing driving period to obtain a characteristic value of the driving transistor (DRT). In order to accurately sense, the sensing driving data voltage Vdata may be calculated and set to be variable according to the threshold voltage Vth_OLED of the organic light emitting diode (OLED).

Here, the calculation and setting of the data voltage Vdata for sensing driving may be performed at a digital level by the controller 140 .

The controller 140 generates sensing-driving data so that the sensing-driving data voltage Vdata varies according to the threshold voltage Vth_OLED of the organic light-emitting diode (OLED).

The data driver 120 receives sensing driving data from the controller 140 and converts it into an analog voltage type sensing driving data voltage (Vdata) and outputs it.

Therefore, in the organic light emitting display device 100 according to the present embodiments, the data driver 120, during the driving transistor sensing driving period for sensing the characteristic value of the driving transistor DRT in the sensing target subpixel SP, The sensing driving data voltage Vdata set based on the threshold voltage Vth_OLED of the organic light emitting diode OLED in the sensing target subpixel SP may be output.

Accordingly, the organic light emitting display device 100 according to the present embodiments performs sensing driving of the driving transistor using the sensing driving data voltage Vdata set based on the threshold voltage Vth_OLED of the organic light emitting diode OLED. As a result, it is possible to accurately sense the characteristic value of the driving transistor DRT in a state in which the organic light emitting diode OLED is not turned on.

More specifically, the data driver 120 is lower than the threshold voltage (Vth_OLED) of the organic light emitting diode (OLED) in the sensing target subpixel (SP) during the driving transistor sensing driving period, and the organic light emitting diode (OLED) in the sensing target subpixel (SP). A data voltage Vdata for sensing driving that is variable according to the threshold voltage Vth_OLED of the light emitting diode OLED may be output.

And, in the driving transistor sensing driving period, a second electrode (eg, a cathode electrode) among the first electrode (eg, an anode electrode or a cathode electrode) and the second electrode (eg, a cathode electrode or an anode electrode) of the organic light emitting diode (OLED) Alternatively, the base voltage EVSS applied to the anode electrode) may be the ground voltage GND, similarly to a period other than the driving transistor sensing driving period.

Therefore, the organic light emitting display device 100 according to the present embodiments removes the influence of the organic light emitting diode (OLED) without changing the base voltage (EVSS) in the driving transistor sensing driving period, thereby reducing the characteristic values of the driving transistor (DRT). can be accurately sensed. In addition, the characteristics of the organic light emitting diode (OLED) in each sub-pixel (SP) may be reflected in the driving transistor sensing driving period to more accurately sense the characteristics of the driving transistor (DRT).

As described above, during the driving transistor sensing driving period, the data driver 120 changes the sensing driving data voltage Vdata according to the threshold voltage Vth_OLED of the organic light emitting diode OLED in the sensing target subpixel SP. ), it is possible to output different sensing driving data voltages Vdata according to the sensing target subpixel SP.

11 is a diagram of the driving transistor DRT while minimizing the influence of the organic light emitting diode OLED without increasing the base voltage EVSS in the driving transistor sensing driving period in the organic light emitting display device 100 according to the present embodiments. 12 is a flowchart of a driving method capable of improving sensing accuracy for characteristic values, and FIG. 12 is a flow chart of a driving transistor DRT without an increase in the base voltage EVSS in the organic light emitting display device 100 according to the present embodiments. This is a diagram for explaining the voltage change of the second node N2 of the driving transistor DRT in the driving transistor sensing driving period for sensing characteristic values and the sensing driving data voltage Vdata in the driving transistor sensing driving period. .

Referring to FIG. 11 , a driving method of the organic light emitting display device 100 according to the present embodiments includes calculating a sensing driving data voltage Vdata (S1110), and the calculated sensing driving data voltage Vdata ) to sense the characteristic value of the driving transistor DRT in the sub-pixel SP to be sensed (S1120), and the sensing target sub-pixel based on the sensing value obtained through the driving transistor sensing drive (S1120). A step of calculating and storing a compensation value for the characteristic value of the driving transistor DRT in the pixel SP (S1130) and the like may be included.

The aforementioned S1110 may be performed by the controller 140 at a digital level.

The aforementioned S1120 may be performed according to the operation of various switches (SPRE, SAM), the data driver 120 and the gate driver 130 under the control of the controller 140 .

Referring to FIG. 12 , in step S1120, the sensing driving data voltage Vdata is applied to the first node N1 of the driving transistor DRT, and the reference voltage is applied to the second node N2 of the driving transistor DRT. The step of applying (S1210), the step of increasing the voltage by floating the second node (N2) of the driving transistor (DRT) (S1220), and the second node (N2) of the driving transistor (DRT) or the driving transistor ( and sensing the voltage of the sensing line SL electrically connected to the second node N2 of the DRT (S1230).

In step S1220, the voltage of the second node N2 of the driving transistor DRT rises until it reaches a voltage state (eg, Vdata - Vth) reflecting the characteristic value of the driving transistor DRT.

In step S1210 described above, the sensing driving data voltage Vdata is calculated based on the threshold voltage Vth_OLED of the organic light emitting diode OLED in the sensing target subpixel SP.

As described above, the organic light emitting diode (OLED) turns- In a non-on state, the characteristic value of the driving transistor DRT can be accurately sensed, and accordingly, a deviation in the characteristic value of the driving transistor DRT can be accurately compensated to help improve image quality.

As described above, by using the sensing driving data voltage Vdata calculated based on the threshold voltage Vth_OLED of the organic light emitting diode OLED in the sensing target subpixel SP, the organic light emitting diode sensing driving is performed. A characteristic value of the driving transistor DRT may be sensed when the light emitting diode OLED is not turned on.

For this reason, in step S1210 in which the driving transistor sensing drive is performed, the base voltage EVSS applied to the second electrode among the first electrode and the second electrode of the organic light emitting diode (OLED) turns on the organic light emitting diode (OLED). -The voltage that does not turn on does not have to be set high.

Therefore, in step S1210 of performing sensing driving of the driving transistor, the base voltage EVSS applied to the second electrode among the first electrode and the second electrode of the organic light emitting diode (OLED) is ground, as shown in FIG. It may be used as a voltage (GND).

Here, the ground voltage (GND) may be a voltage used in a general image driving section rather than a driving transistor sensing driving section, and may be, for example, 0V, and in some cases, a voltage slightly higher or slightly lower than 0V. can

As such, in the driving transistor sensing driving period, the driving transistor sensing driving can be performed without changing the base voltage EVSS and without the influence of the organic light emitting diode (OLED), so that a separate base voltage control circuit is not required. There are advantages.

Meanwhile, referring to FIG. 12 , the data voltage Vdata for sensing and driving is variable according to the threshold voltage Vth_OLED of the organic light emitting diode OLED in the sensing target subpixel SP, and the organic light emitting display panel 110 It can also be varied according to the threshold voltage distribution for the driving transistors DRT in .

Here, the threshold voltages of all the driving transistors DRT disposed on the light emitting display panel 110 have a predetermined distribution between the lower limit value Vth_LSL and the upper limit value Vth_USL.

More specifically, the data voltage Vdata for sensing and driving is set in proportion to the threshold voltage Vth_OLED of the organic light emitting diode OLED in the sensing target subpixel SP, and is set in proportion to the upper limit value Vth_USL on the threshold voltage distribution. It can be set in inverse proportion.

The data voltage Vdata for sensing driving may be expressed as in Equation 1 below.

In Equation 1, Vdata is a sensing driving data voltage used to sense the characteristic value of the driving transistor DRT in the corresponding subpixel SP, and Vth_OLED is the organic light emitting diode (OLED) in the corresponding subpixel SP. ) is the threshold voltage of Further, Vth_USL is an upper limit value on the threshold voltage distribution for the threshold voltages of all driving transistors DRT disposed on the organic light emitting display panel 110 .

As described above, the threshold voltage (Vth_OLED) of the organic light emitting diode (OLED) in the sensing target subpixel (SP) and the upper limit value (Vth_USL) of the threshold voltage distribution for all driving transistors DRT in the organic light emitting display panel 110 ), by setting the data voltage Vdata for sensing driving, the voltage state of the second node N2 of the driving transistor DRT directly connected to the first electrode of the organic light emitting diode OLED is changed to the organic light emitting diode. (OLED) can be accurately made into a non-turned-on state.

FIG. 13 is a diagram of the driving transistor DRT while minimizing the influence of the organic light emitting diode OLED without increasing the base voltage EVSS in the driving transistor sensing driving period in the organic light emitting display device 100 according to the present embodiments. It is another flowchart for a driving method capable of improving sensing accuracy for characteristic values.

Referring to FIG. 13 , prior to step S1110 of calculating the data voltage Vdata for sensing driving, organic light emitting diode sensing for sensing the threshold voltage Vth_OLED of the organic light emitting diode OLED in the sensing target subpixel SP. A step of driving (S1310) may further proceed.

Accordingly, in step S1110 of calculating the sensing driving data voltage Vdata, the threshold voltage of the organic light emitting diode OLED in the sensing target subpixel SP used to calculate the sensing driving data voltage Vdata ( Vth_OLED) may be the threshold voltage (Vth_OLED) of the organic light emitting diode (OLED) in the subpixel (SP) to be sensed obtained by actually being sensed in the organic light emitting diode sensing driving period that proceeded before the driving transistor sensing driving period.

Accordingly, the organic light emitting display device 100 according to the present embodiments reflects the characteristics of the organic light emitting diode (OLED) in each subpixel (SP) in the driving transistor sensing driving period to determine the characteristics of the driving transistor (DRT). More accurate sensing is possible.

Meanwhile, as described above, the analog-to-digital converter 410 is electrically connected to the sensing line SL, and the voltage of the sensing line SL electrically connected to the second node N2 of the driving transistor DRT. It converts into a sensed value corresponding to a digital value and outputs it.

The voltage Vsen sensed by the analog-to-digital converter 410 may change according to the variation of the sensing driving data voltage Vdata.

For example, in the case of driving by sensing the driving transistor for sensing the threshold voltage (Vth) of the driving transistor (DRT), the voltage (Vsen) sensed by the analog-to-digital converter 410 is the data voltage (Vdata) for sensing and driving. Since it is the difference (Vdata-Vth) of the threshold voltage (Vth) of the driving transistor (DRT), it may change according to the data voltage (Vdata) for sensing and driving.

Therefore, in order to improve analog-to-digital conversion performance, the analog-to-digital conversion range of the analog-to-digital converter 410 should be appropriately variable.

That is, the sensing value of the analog-to-digital converter 410 must fall within the analog-to-digital conversion range of the analog-to-digital converter 410 .

More specifically, a digital value corresponding to the sensing voltage of the analog-to-digital converter 410 should be located at the center of the analog-to-digital conversion range (digital value range) of the analog-to-digital converter 410 .

Accordingly, after step S1110 of calculating the data voltage Vdata for sensing driving and before step S1120 of performing sensing driving of the driving transistor, a step of adjusting the analog-to-digital conversion range of the analog-to-digital converter 410 (S1320) is further performed. can

As described above, even if the driving transistor sensing drive is performed by varying the data voltage Vdata for sensing driving in consideration of the threshold voltage Vth_OLED of the organic light emitting diode (OLED), the analog-to-digital converter 410 performs accurate analog-to-digital conversion The function can be performed, and thus, the characteristic value of the driving transistor DRT can be accurately sensed.

Referring to FIG. 11, after adjusting the analog-to-digital conversion range of the analog-to-digital converter 140 in step S1320, the characteristic information (eg, gain, offset, etc.) of the analog-to-digital converter 140 is sensed and compensated (corrected). Step S1330 may be further performed.

Meanwhile, in step S1310 of performing organic light emitting diode sensing driving for sensing the threshold voltage Vth_OLED of the organic light emitting diode OLED, the threshold voltage of the organic light emitting diode OLED is not affected by the driving transistor DRT. In order to accurately sense (Vth_OLED), during the organic light emitting diode sensing period, the data line DL electrically connected to the first node N1 of the driving transistor DRT in the sensing target subpixel SP is connected to the sensing target subpixel SP. A data voltage for turning off the driving transistor DRT in the pixel SP may be applied.

Here, the data voltage for turning off the driving transistor DRT in the subpixel SP to be sensed may be, for example, the black data voltage Vblack.

During the organic light emitting diode sensing period, the voltage of the sensing line SL electrically connected to the first electrode of the organic light emitting diode OLED in the sensing target subpixel SP decreases.

While the voltage of the sensing line SL falls, the organic light emitting diode OLED emits light.

Also, when the voltage of the sensing line SL becomes lower than the voltage capable of turning on the organic light emitting diode OLED, the organic light emitting diode OLED stops emitting light.

At this time, the analog-to-digital converter 410 senses the voltage of the sensing line SL.

The voltage sensed by the analog-to-digital converter 410 is a voltage obtained by adding the threshold voltage Vth_OLED of the organic light emitting diode OLED to the base voltage EVSS. If the base voltage EVSS is the ground voltage GND of 0V, the voltage sensed by the analog-to-digital converter 410 corresponds to the threshold voltage Vth_OLED of the organic light emitting diode OLED.

As described above, by setting the data voltage to a voltage capable of turning off the driving transistor DRT, the organic light emitting diode sensing drive is performed, thereby increasing the threshold voltage of the organic light emitting diode OLED without the influence of the driving transistor DRT. (Vth_OLED) can be accurately sensed.

Hereinafter, the organic light emitting diode sensing driving method will be described in more detail.

14 is a flowchart of an organic light emitting diode sensing driving method for sensing the threshold voltage (Vth_OLED) of the organic light emitting diode (OLED) in the organic light emitting display device 100 according to the present embodiments, and FIG. 15 is a flowchart of this embodiment. In the OLED sensing driving method for sensing the threshold voltage (Vth_OLED) of the organic light emitting diode (OLED) in the organic light emitting display device 100 according to the examples, this is a diagram showing circuit states at each stage. 16 illustrates a voltage change of a sensing line SL in an organic light emitting diode sensing drive section for sensing the threshold voltage Vth_OLED of the organic light emitting diode OLED in the organic light emitting display device 100 according to the present embodiments. is a drawing showing

Referring to FIGS. 14 and 15 , the organic light emitting diode sensing driving step ( S1310 ) includes an organic light emitting diode discharging step ( S1420 ) and an organic light emitting diode threshold voltage sensing step ( S1430 ).

In the organic light emitting diode discharging step ( S1420 ), the driving transistor DRT is in an off state and the second transistor T2 is in an on state.

At the start of the organic light emitting diode discharge step ( S1420 ), the sensing line SL is initialized with an initialization voltage Vinit higher than the threshold voltage Vth_OLED of the organic light emitting diode OLED.

Accordingly, in the organic light emitting diode discharging step ( S1420 ), the organic light emitting diode (OLED) emits light while current flows through the organic light emitting diode (OLED).

In the organic light emitting diode discharging step (S1420), in order to turn off the driving transistor DRT, the first scan signal SCAN1 of the turn-off level voltage (eg, low level voltage) is applied to the first transistor T1 ) to turn off the first transistor T1 or to turn off the driving transistor DRT through the turned-on first transistor T1 (e.g., black data voltage Vblack )) may be applied to the first node N1 of the driving transistor DRT.

In step S1420, a discharge operation occurs while current flows through the organic light emitting diode (OLED), and accordingly, the voltage of the first electrode of the organic light emitting diode (OLED), that is, the second node (N2) of the driving transistor (DRT) The voltage (V2) of is lowered.

Therefore, as shown in FIG. 16, since the second transistor T2 is turned on in step S1420, the voltage V2 of the second node N2 of the driving transistor DRT and the sensing line The voltage (Vsl) of (SL) also decreases.

While the voltage of the first electrode of the organic light emitting diode (OLED), that is, the voltage (V2) of the second node (N2) of the driving transistor (DRT) is lowered, that is, the voltage (Vsl) of the sensing line (SL) While low, the organic light emitting diode (OLED) is in a light emitting state (on state).

Referring to FIG. 16 , the voltage of the first electrode of the organic light emitting diode (OLED), that is, the voltage (V2) of the second node (N2) of the driving transistor (DRT) turns off the organic light emitting diode (OLED). When the voltage decreases, the organic light emitting diode OELD turns off (stops emitting light).

Here, the voltage at which the organic light emitting diode OLED is turned off is a voltage obtained by adding the threshold voltage Vth_OLED of the organic light emitting diode OLED to the base voltage EVSS.

If the base voltage EVSS is the ground voltage GND of 0V, the voltage at which the organic light emitting diode OLED is turned off corresponds to the threshold voltage Vth_OLED of the organic light emitting diode OLED.

When the organic light emitting diode (OELD) stops emitting light, that is, when the organic light emitting diode (OLED) is turned off, the organic light emitting diode threshold voltage sensing step ( S1430 ) proceeds.

In the OLED threshold voltage sensing step (S1430), as shown in FIG. 16, the sampling switch SAM is turned on and the analog-to-digital converter 410 is electrically connected to the sensing line SL.

Accordingly, the analog-to-digital converter 410 senses the first electrode of the organic light emitting diode (OLED) or the voltage (Vsl) of the sensing line (SL) electrically connected to the first electrode of the organic light emitting diode (OLED).

In this case, the sensed voltage Vsl may be the threshold voltage Vth_OLED of the organic light emitting diode OLED or a voltage corresponding to the threshold voltage Vth_OLED of the organic light emitting diode OLED (EVSS+Vth_OLED).

According to the organic light emitting diode sensing and driving method described above, the threshold voltage Vth_OLED of the organic light emitting diode (OLED) can be accurately sensed.

Meanwhile, referring to FIGS. 14 and 15 , prior to the organic light emitting diode discharging step (S1420), the sensing line SL is initialized with an initialization voltage Vinit higher than the threshold voltage Vth_OLED of the organic light emitting diode OLED. A sensing line initialization step (S1410) may further proceed.

In this sensing line initialization step ( S1410 ), the second transistor T2 may be in an on state or an off state.

Meanwhile, a sensing line initialization step (S1410) may be separately prepared to separately apply the initialization voltage (Vinit) set to a voltage higher than the threshold voltage (Vth_OLED) of the organic light emitting diode (OLED) to the sensing line (SL). .

Unlike this, in connection with the light emission operation of the organic light emitting diode (OLED) for image driving, the voltage of the sensing line (SL) is converted into an initialization voltage (Vinit) for sensing the threshold voltage (Vth) of the organic light emitting diode (OLED). By making it, the sensing line SL may be initialized.

This case will be described with reference to FIGS. 17 and 18 .

FIG. 17 is another flow chart of an organic light emitting diode sensing driving method for sensing the threshold voltage (Vth_OLED) of the organic light emitting diode (OLED) in the organic light emitting display device 100 according to the present embodiments. FIG. In the organic light emitting diode display device 100 according to the exemplary embodiments, in the organic light emitting diode sensing driving period for sensing the threshold voltage Vth_OLED of the organic light emitting diode (OLED), the main signals SCAN1, SCAN2, SPRE, SAM, It is a diagram showing voltage changes between Vdata) and the sensing line SL.

17 and 18, the light emitting operation of the organic light emitting diode (OLED) includes a light emission initialization step (S1710) for light emission of the organic light emitting diode (OLED), and an organic light emitting diode (OLED) emitting light. It proceeds to a light emitting step (S1720).

In the light emission initialization step S1710, the first scan signal SCAN1 and the second scan signal SCAN2 of the turn-on level voltage (high level voltage) are applied to the first transistor T1 and the second transistor T2. do. Accordingly, the first transistor T1 and the second transistor T2 are turned on.

In the light emission initialization step (S1710), the initialization switch SPRE is turned on, and the reference voltage Vref is applied to the sensing line SL.

In addition, in the emission initialization step (S1710), the data driver 120 outputs the image driving data voltage Vdata.

Accordingly, in the emission initialization step S1710, the image driving data voltage Vdata is applied to the first node N1 of the driving transistor DRT, and the reference voltage is applied to the second node N2 of the driving transistor DRT. A voltage Vref is applied.

17 and 18, in the organic light emitting diode light emitting step (S1720), the first scan signal SCAN1 of the turn-off level voltage (low level voltage) is applied to the first transistor T1, The first transistor T1 is turned off. Also, the initialization switch SPRE is turned off.

Accordingly, the first node N1 and the second node N2 of the driving transistor DRT are floated.

Accordingly, the voltage of each of the first node N1 and the second node N2 of the driving transistor DRT increases. At this time, when the second transistor T2 is in an on state, the voltage of the sensing line SL also rises.

When the voltage V2 of the second node N2 of the driving transistor DRT rises and becomes higher than the threshold voltage Vth_OLED of the organic light-emitting diode OLED, the organic light-emitting diode OLED starts to emit light.

17 and 18, in the organic light emitting diode light emitting step (S1720), as the voltage V2 of the second node N2 of the driving transistor DRT increases, the voltage of the sensing line SL ( Vsl) also rises, and at some point becomes the initialization voltage (Vinit) for driving the organic light emitting diode sensing.

This time point becomes a sensing line initialization time point for organic light emitting diode sensing drive.

After the sensing line initialization point, the organic light emitting diode discharge step (S1420) and the organic light emitting diode threshold voltage sensing step (S1430) proceed, so that the organic light emitting diode sensing driving (S1310) proceeds, and the organic light emitting diode (OLED) threshold The voltage (Vth_OLED) may be sensed.

19 is a block diagram of a controller 140 according to the present embodiments.

Referring to FIG. 19 , the controller 140 according to the present embodiments performs sensing required for driving the driving transistor sensing for sensing the characteristic value (eg, threshold voltage, mobility) of the driving transistor DRT in the subpixel to be sensed. It is transmitted from the sensing driving data generator 1910 that generates driving data, the sensing driving data output unit 1920 that outputs the sensing driving data to the data driver 120, and the analog-to-digital converter (ADC). Compensation unit 430 that calculates and outputs a compensation value for the characteristic value of the driving transistor DRT in the subpixel to be sensed based on the sensing data stored in the memory 420 or received from the analog-to-digital converter (ADC) can do.

The sensing driving data generator 1910 may generate sensing driving data based on the threshold voltage Vth_OLED of the organic light emitting diode (OLED) in the sensing target subpixel.

The data driver 120 may receive the sensing driving data generated by the sensing driving data generator 1910, convert the sensing driving data voltage Vdata, and output the data voltage Vdata to the corresponding data line during the sensing driving period of the driving transistor. .

According to the present embodiments as described above, it is possible to provide a controller 140, an organic light emitting display device 100, and a driving method capable of accurately sensing characteristic values of driving transistors without the influence of organic light emitting diodes. there is.

In addition, according to the present embodiments, the characteristic value of the driving transistor can be accurately sensed without the influence of the organic light emitting diode without arbitrarily adjusting the base voltage applied to the second electrode of the first electrode and the second electrode of the organic light emitting diode. A controller 140, an organic light emitting display device 100, and a driving method thereof may be provided.

In addition, according to the present embodiments, the controller 140 reflects the characteristics of the organic light emitting diode in each subpixel and performs a sensing drive to sense the characteristic values of the driving transistors, thereby more accurately sensing the characteristic values of the driving transistors. ), an organic light emitting display device 100 and a driving method thereof.

The above description and accompanying drawings are merely illustrative of the technical idea of the present invention, and those skilled in the art can combine the configuration within the scope not departing from the essential characteristics of the present invention. , various modifications and variations such as separation, substitution and alteration will be possible. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but to explain, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be construed according to the claims below, and all technical ideas within the equivalent range should be construed as being included in the scope of the present invention.

100: organic light emitting display device
110: organic light emitting display panel
120: data driver
130: gate driver
140: controller

Claims (17)

an organic light emitting display panel in which a plurality of subpixels defined by a plurality of data lines and a plurality of gate lines are arranged, and an organic light emitting diode and a driving transistor for driving the organic light emitting diode are disposed in each subpixel;
a data driver driving the plurality of data lines;
a gate driver driving the plurality of gate lines; and
a controller controlling the data driver and the gate driver;
The data driver,
During a driving transistor sensing driving period for sensing a characteristic value of a driving transistor in a sensing target subpixel, a data voltage for sensing and driving set based on a threshold voltage of an organic light emitting diode in the sensing target subpixel is output,
The threshold voltage of the organic light emitting diode in the sensing target subpixel is,
a threshold voltage of the organic light emitting diode in the subpixel to be sensed obtained in an organic light emitting diode sensing driving period performed before the driving transistor sensing driving period;
The data voltage for sensing and driving is varied according to a threshold voltage of an organic light emitting diode in the sensing target subpixel;
During the driving transistor sensing driving period, the organic light emitting diode is in a turned-off state. According to claim 1,
The data driver,
An organic light emitting display device having a threshold voltage lower than a threshold voltage of an organic light emitting diode in the sensing target subpixel. According to claim 1,
During the driving transistor sensing driving period,
The base voltage applied to the cathode electrode of the organic light emitting diode is a ground voltage. According to claim 1,
The data voltage for driving the sensing is
An organic light emitting display device that is variable according to a threshold voltage distribution of driving transistors in the organic light emitting display panel. According to claim 4,
The data voltage for driving the sensing is
set in proportion to the threshold voltage of the organic light emitting diode in the sensing target subpixel;
An organic light emitting display device set in inverse proportion to an upper limit of the threshold voltage distribution. delete According to claim 1,
During the organic light emitting diode sensing period,
A data voltage for turning off a driving transistor in the sensing target subpixel is applied to a data line electrically connected to a first node of a driving transistor in the sensing target subpixel. According to claim 7,
During the organic light emitting diode sensing period,
The organic light emitting diode in the sensing target subpixel stops emitting light while a voltage of a sensing line electrically connected to a first electrode of the organic light emitting diode in the sensing target subpixel falls. According to claim 1,
An analog-to-digital converter converting a voltage of a sensing line electrically connected to the second node of the driving transistor into a sensing value corresponding to a digital value and outputting the converted digital value;
An organic light emitting display device in which an analog-to-digital conversion range of the analog-to-digital converter is variable before the driving transistor sensing driving period. An organic light emitting display panel in which a plurality of subpixels defined by a plurality of data lines and a plurality of gate lines are arranged, and an organic light emitting diode and a driving transistor for driving the organic light emitting diode are disposed in each subpixel; A method of driving an organic light emitting display device comprising a data driver driving data lines, a gate driver driving the plurality of gate lines, and a controller controlling the data drivers and the gate drivers, the method comprising:
calculating a data voltage for sensing driving;
performing sensing driving of a driving transistor for sensing a characteristic value of a driving transistor in a subpixel to be sensed using the sensing driving data voltage; and
Calculating and storing a compensation value for a characteristic value of a driving transistor in the subpixel to be sensed based on a sensing value obtained through sensing driving of the driving transistor;
In the step of performing the driving transistor sensing drive,
applying the data voltage for sensing and driving to a first node of the driving transistor and applying a reference voltage to a second node of the driving transistor;
increasing the voltage of the second node of the driving transistor by floating the second node of the driving transistor; and
sensing a voltage of a second node of the driving transistor or a sensing line electrically connected to the second node of the driving transistor;
In the step of calculating the data voltage for sensing driving,
calculating a data voltage for sensing and driving based on a threshold voltage of an organic light emitting diode in the sensing target subpixel;
Prior to the step of calculating the data voltage for sensing driving, further comprising: performing organic light emitting diode sensing driving for sensing a threshold voltage of an organic light emitting diode in the sensing target subpixel;
The data voltage for sensing and driving is varied according to a threshold voltage of an organic light emitting diode in the sensing target subpixel;
In the step of performing the sensing driving of the driving transistor, the organic light emitting diode is in a turned-off state. According to claim 10,
The data voltage for driving the sensing is
A method of driving an organic light emitting display device lower than a threshold voltage of an organic light emitting diode in the sensing target subpixel. According to claim 11,
The data voltage for driving the sensing is
A method of driving an organic light emitting display device that is variable according to a threshold voltage distribution of driving transistors in the organic light emitting display panel. According to claim 10,
In the step of performing the driving transistor sensing drive,
The base voltage applied to the second electrode among the first electrode and the second electrode of the organic light emitting diode is a ground voltage. delete According to claim 10,
In the step of driving the organic light emitting diode sensing,
flowing a current to the organic light emitting diode in a state in which the driving transistor is turned off; and
sensing a voltage of a first electrode of the organic light emitting diode or a sensing line electrically connected to the first electrode of the organic light emitting diode when the organic light emitting diode is turned off;
The sensed voltage corresponds to a threshold voltage of the organic light emitting diode or a threshold voltage of the organic light emitting diode. According to claim 10,
After the step of calculating the data voltage for the sensing drive and before the step of performing the sensing drive of the driving transistor,
The method of driving an organic light emitting display device further comprising adjusting an analog-to-digital conversion range of an analog-to-digital converter that converts a voltage of a sensing line electrically connected to the second node of the driving transistor into a sensed value corresponding to a digital value and outputs the same. . a sensing driving data generating unit configured to generate sensing driving data required for sensing driving of a driving transistor for sensing a characteristic value of a driving transistor in a subpixel to be sensed;
a sensing drive data output unit outputting the sensing drive data; and
A compensator calculating and outputting a compensation value for a characteristic value of a driving transistor in the sensing target subpixel based on stored or received sensing data;
The sensing driving data generating unit,
generating data for sensing and driving based on a threshold voltage of an organic light emitting diode in the sensing target subpixel;
The threshold voltage of the organic light emitting diode in the sensing target subpixel is,
a threshold voltage of the organic light emitting diode in the subpixel to be sensed obtained in an organic light emitting diode sensing driving period performed before the driving transistor sensing driving period;
The data voltage for sensing and driving is varied according to a threshold voltage of an organic light emitting diode in the sensing target subpixel;
The organic light emitting diode is in a turned-off state while the driving transistor sensing drive is in progress.

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