KR102379393B1 - Organic light emitting display device - Google Patents

Abstract

The present embodiments relate to an organic light emitting diode display device capable of performing a characteristic value sensing operation between driving transistors in real time during a blank time period, and a driving method thereof.

Description

Organic light emitting display device {ORGANIC LIGHT EMITTING DISPLAY DEVICE}

The present embodiments relate to an organic light emitting display device that displays an image.

Recently, an organic light emitting display device, which has been spotlighted as a display device, uses an organic light emitting diode (OLED) that emits light by itself, so that the response speed is fast and the contrast ratio, luminous efficiency, luminance, and viewing angle are large. There are advantages.

Each sub-pixel of the organic light emitting display device may include an organic light emitting diode and a driving transistor driving the same. Each sub-pixel of the organic light emitting display device may include an organic light emitting diode and a driving transistor driving the same.

Meanwhile, the driving transistor in each sub-pixel has unique characteristics such as threshold voltage and mobility. In addition, each driving transistor is degraded according to the driving time, so that unique characteristic values such as threshold voltage and mobility may change.

Due to these points, depending on the difference in driving time between the driving transistors in each subpixel, a difference in the degree of deterioration between the driving transistors may occur, and a variation in characteristic values between the driving transistors may also occur.

The deviation of the characteristic values between the driving transistors may cause a luminance deviation between the respective sub-pixels, which may be a major factor causing image quality deterioration.

Accordingly, various technologies have been developed to compensate for variation in characteristic values between driving transistors.

Meanwhile, in order to compensate for the characteristic value deviation between the driving transistors, a sensing operation for sensing a characteristic value or a change amount of a characteristic value is performed. Since this sensing operation takes quite a long time, the sensing operation is performed on the sub-pixels on the organic light emitting display panel. It takes a lot of time to do it.

Accordingly, there has been a problem in that the characteristic value sensing operation between the driving transistors cannot be performed in real time while the power is on, that is, while the image is being driven.

It is an object of the present exemplary embodiments to provide an organic light emitting diode display capable of performing a characteristic value sensing operation between driving transistors in real time during a blank time period.

It is an object of the present exemplary embodiments to provide an organic light emitting diode display that does not perform or minimizes a time for not performing or performing a characteristic value sensing operation between driving transistors after a power-off signal is generated.

According to an exemplary embodiment, an organic light emitting display panel in which a plurality of data lines and a plurality of gate lines are disposed and a plurality of subpixels are disposed, a data driver driving the plurality of data lines, and a gate driving the plurality of gate lines It is possible to provide an organic light emitting display device including a driver, a controller for controlling the data driver and the gate driver, and the like.

In order to sense the threshold voltage of the driving transistor in the subpixels of the organic light emitting display panel, n (n≥2) times of threshold voltage real-time sensing driving periods exist, and all of the n times of threshold voltage real-time sensing driving periods or Some may be included in the blank time interval.

According to another embodiment, an organic light emitting display panel in which a plurality of subpixels including an organic light emitting diode and a driving transistor are disposed and n (n≥2) times of threshold voltage real-time sensing driving period in which all or part of the sub-pixels are disposed in a blank time period It is possible to provide an organic light emitting display device including a sensing unit for sensing a threshold voltage of a driving transistor in sub-pixels of an organic light emitting display panel during operation.

According to the present exemplary embodiments as described above, it is possible to provide an organic light emitting diode display capable of performing a characteristic value sensing operation between driving transistors in real time during a blank time period.

Also, according to the present exemplary embodiments, it is possible to provide an organic light emitting diode display capable of minimizing the time for not performing or performing a characteristic value sensing operation between driving transistors after a power-off signal is generated.

1 is a schematic system configuration diagram of an organic light emitting diode display according to example embodiments.
2 is an exemplary diagram of a sub-pixel structure of an organic light emitting diode display according to example embodiments.
3 is an exemplary diagram of a sub-pixel compensation circuit of an organic light emitting diode display according to example embodiments.
4 is a graph illustrating a voltage change of a sensing node or a first node of a driving transistor during a threshold voltage sensing operation of the organic light emitting diode display according to the present exemplary embodiment.
5 and 6 are diagrams illustrating an initial threshold voltage sensing and sensing a threshold voltage change amount of the organic light emitting diode display according to the present exemplary embodiments.
7 is a diagram illustrating a voltage change of a sensing node or a first node of a driving transistor when a threshold voltage is sensed through one sensing operation in the organic light emitting diode display according to the present exemplary embodiments.
8 is an exemplary diagram of a threshold voltage sensing timing in the organic light emitting diode display according to the present exemplary embodiments.
FIG. 9 is a diagram for explaining a method of sensing a threshold voltage in real time through n times of threshold voltage real-time sensing driving in the organic light emitting diode display according to the present embodiments.
10 is a diagram schematically illustrating timing of a threshold voltage real-time sensing operation during a blank time period in the organic light emitting diode display according to the present exemplary embodiments.
11 is a diagram schematically illustrating timing of a threshold voltage real-time sensing operation during a blank time period in the organic light emitting diode display according to the present exemplary embodiments.
12 is a diagram illustrating timing of n times of real-time threshold voltage sensing driving with respect to threshold voltage sensing of a driving transistor in sub-pixels of an organic light emitting display panel according to the present exemplary embodiment.
13 is a conceptual diagram of real-time sensing of a threshold voltage in a threshold voltage real-time sensing driving in the organic light emitting diode display according to the present exemplary embodiments.
14 is a graph illustrating a voltage change of a sensing node when the threshold voltage is sensed in real time in the threshold voltage real-time sensing driving of FIG. 13 .
15 is a conceptual diagram of a threshold voltage real-time sensing driving in the organic light emitting diode display according to the present exemplary embodiments.
16 is a graph illustrating a voltage change of the sensing node Ns when the threshold voltage real-time sensing operation is performed n times during the threshold voltage real-time sensing operation of FIG. 15 .
17 is a diagram conceptually illustrating sensing and compensation using the threshold voltage real-time sensing driving of the organic light emitting diode display according to the present embodiments.
19 to 23 illustrate the sequence of real-time sensing of the threshold voltage for the threshold voltage of the entire region of the organic light emitting display panel during the blank time period.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. In adding reference numerals to components of each drawing, the same components may have the same reference numerals as much as possible even though they are indicated in 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.

In addition, in describing the components of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only for distinguishing the elements from other elements, and the essence, order, order, or number of the elements are not limited by the terms. When it is described that a component is “connected”, “coupled” or “connected” to another component, the component may be directly connected or connected to the other component, but other components may be interposed between each component. It should be understood that each component may be “interposed” or “connected”, “coupled” or “connected” through another component.

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

Referring to FIG. 1 , in the organic light emitting diode display 100 according to the present exemplary embodiments, a plurality of data lines DL and a plurality of gate lines GL are disposed, and a plurality of subpixels SP are of a matrix type. A plurality of data lines are sequentially supplied to the driving data driver 120 by supplying data voltages to the organic light emitting display panel 110 arranged as It includes a gate driver 130 that sequentially drives the gate lines, a data driver 120 , and a controller 140 that controls the gate driver 130 .

The controller 140 supplies various control signals DCS and GCS to the data driver 120 and the gate driver 130 to control the data driver 120 and the gate driver 130 .

The controller 140 starts scanning according to the timing implemented in each frame, and converts the input image data input from the outside according to the data signal format used by the data driver 120 to convert the converted image data DATA. output and control the data operation at an appropriate time according to the scan.

The controller 140 may be implemented by including at least one timing controller.

The gate driver 130 sequentially drives the plurality of gate lines by sequentially supplying a scan signal of an on voltage or an off voltage to the plurality of gate lines under the control of the controller 140 .

The gate driver 130 may be positioned on only one side of the organic light emitting display panel 110 as shown in FIG. 1 or, in some cases, on both sides, depending on a driving method.

Also, the gate driver 130 may include one or more gate driver integrated circuits.

Each gate driver integrated circuit 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 a gate in (GIP) method. Panel) type and may be 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.

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

When a specific gate line is opened, the data driver 120 converts the image data DATA received from the controller 140 into an analog data voltage and supplies it to the data lines, thereby driving a plurality of data lines.

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

Each source driver integrated circuit 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 the organic light emitting display panel. It may be directly disposed on the 110 , or may be integrated and disposed on the organic light emitting display panel 110 in some cases.

Each source driver integrated circuit may be implemented in 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 .

Each source driver integrated circuit may include a logic unit including a shift register and a latch circuit, a digital analog converter (DAC), an output buffer, and the like, and in some cases, the characteristics ( Example: A sensing unit (sensor) for sensing characteristics of a sub-pixel may be further included to compensate for the threshold voltage and mobility of the driving transistor, the threshold voltage of the organic light emitting diode, the luminance of the sub-pixel, etc.).

On the other hand, the controller 140, along with the input image data, a vertical synchronization signal (Vsync), a horizontal synchronization signal (Hsync), an input data enable (DE: Data Enable) signal, various types including a clock signal (CLK), etc. Timing signals are received from the outside (eg host system).

The controller 140 converts the input image data input from the outside to match the data signal format used by the data driver 120 and outputs the converted image data, as well as the data driver 120 and the gate driver 130 . In order to control the data driver 120 and the gate driver 130 by receiving a timing signal such as a vertical synchronization signal (Vsync), a horizontal synchronization signal (Hsync), an input DE signal, and a clock signal to generate various control signals output as

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: Various gate control signals (GCS: Gate Control Signal) including Gate Output Enable) are output.

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 a scan signal (gate pulse). The gate output enable signal GOE specifies timing information of one or more gate driver integrated circuits.

In addition, the controller 140 controls the data driver 120 , a source start pulse (SSP), a source sampling clock (SSC), and a source output enable signal (SOE: Source Output). Enable) and output various data control signals (DCS: Data Control Signal).

Here, the source start pulse SSP controls the 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 of the source driver integrated circuits. The source output enable signal SOE controls the output timing of the data driver 120 .

Referring to FIG. 1 , the controller 140 connects the source printed circuit board to which the source driver integrated circuit is bonded and a connection medium such as a flexible flat cable (FFC) or a flexible printed circuit (FPC). It may be disposed on a control printed circuit board connected through the.

The control printed circuit board includes a power controller (not shown) for supplying various voltages or currents to the organic light emitting display panel 110 , the data driver 120 , and the gate driver 130 , or controlling various voltages or currents to be supplied. more can be placed. Such a power controller is also referred to as a power management integrated circuit (PMIC).

The source printed circuit board and the control printed circuit board mentioned above may be a single printed circuit board.

In each of the plurality of sub-pixels disposed on the organic light emitting display panel 110 according to the present embodiments, an organic light emitting diode (OLED), a driving transistor (DRT) and storage for driving the organic light emitting diode (OLED) A circuit element such as a capacitor may be basically included.

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

Hereinafter, a sub-pixel structure for sensing and compensating characteristic values such as a threshold voltage and mobility of the driving transistor DRT will be exemplarily described.

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

Referring to FIG. 2 , each subpixel SP disposed in the organic light emitting display panel 110 according to the present exemplary embodiments includes an organic light emitting diode (OLED) and a driving transistor ( DRT: A driving transistor connected between the second node N2 of the driving transistor DRT and the data line DL and transferring the data voltage Vdata to the second node N2 of the driving transistor DRT. A switching transistor (SWT), a storage capacitor (Cst) that maintains a constant voltage for one frame time, a first node (N1) and a reference voltage (Vref) of the driving transistor (DRT) may include a sensing transistor (SENT) electrically connected between a reference voltage line (RVL) for supplying the .

Referring to FIG. 2 , an organic light emitting diode (OLED) includes a first electrode (eg, an anode electrode or a cathode electrode), an organic layer, and a second electrode (eg, a cathode electrode or an anode electrode).

As an example, the first electrode of the organic light emitting diode OLED is connected to the first node N1 of the driving transistor DRT, and the second electrode of the organic light emitting diode OLED supplies the base voltage EVSS. can be connected with

Referring to FIG. 2 , the driving transistor DRT supplies a driving current to the organic light emitting diode OLED to drive the organic light emitting diode OLED, and a first node corresponding to a source node or a drain node ( N1), a second node N2 corresponding to a gate node, and a third node N3 corresponding to a drain node or a source node.

For example, the first node N1 of the driving transistor DRT may be electrically connected to the first electrode or the second electrode of the organic light emitting diode OLED. Also, the first node N1 of the driving transistor DRT may be electrically connected to a source node or a drain node of the sensing transistor SENT. The second node N2 of the driving transistor DRT may be electrically connected to a source node or a drain node of the switching transistor SWT, and the third node N3 is a driving voltage line supplying the driving voltage EVDD. DVL) and may be electrically connected.

Referring to FIG. 2 , the switching transistor SWT is a transistor that transfers a data voltage Vdata to an N2 node corresponding to the gate node of the driving transistor DRT, and includes the N2 node and the data line ( DL) and may be turned on by the scan signal SCAN applied to the gate node to transfer the data voltage Vdata to the N2 node of the driving transistor DRT.

Referring to FIG. 2 , the storage capacitor Cst may be electrically connected between the first node N1 and the second node N2 of the driving transistor DRT.

Referring to FIG. 2 , the sensing transistor SENT is electrically connected between the first node of the driving transistor DRT and the reference voltage line RVL, and is a type of a scan signal applied to the gate node, the sense signal SENSE. ) can be controlled by Here, any point on the reference voltage line RVL corresponds to the sensing node Ns.

The sensing transistor SENT is turned on to apply the reference voltage Vref supplied through the reference voltage line RVL to the first node N1 of the driving transistor DRT.

Referring to FIG. 2 , the gate node of the switching transistor SWT and the gate node of the sensing transistor SENT may be electrically connected to the same gate line to receive the same gate signal. In this case, the scan signal SCAN and the sense signal SENSE are the same gate signal.

Alternatively, the gate node of the switching transistor SWT and the gate node of the sensing transistor SENT may be electrically connected to different gate lines. In this case, each of the scan signal SCAN and the sense signal SENSE is a different gate line signal.

Meanwhile, each driving transistor DRT has characteristic values such as a threshold voltage (Vth) and mobility. Also, the characteristic value of the driving transistor DRT may be changed as deterioration proceeds according to the driving time.

For this reason, a difference in the degree of deterioration may exist between the driving transistors DRT in each sub-pixel, and a deviation in characteristic values between the driving transistors DRT in each pixel may exist.

A characteristic value deviation between the driving transistors DRT in each sub-pixel may cause a luminance deviation between the respective sub-pixels, which may be a major factor causing image quality deterioration.

In addition to deviations in characteristic values between the driving transistors DRT (threshold voltage deviation, mobility deviation), as well as deviations in characteristic values between the organic light emitting diodes (OLEDs) (threshold voltage deviation, etc.) may exist.

In the present specification, the deviation of the characteristic value between the driving transistors DRT and the deviation of the characteristic value between the organic light emitting diodes (OLED) is also referred to as “sub-pixel characteristic value deviation”.

Accordingly, in order to improve the image quality, compensation for the sub-pixel characteristic value deviation is required.

Accordingly, as shown in FIG. 3 , the organic light emitting display device 100 according to the present exemplary embodiments includes a sensing configuration and a compensation configuration for sensing the sub-pixel characteristic value deviation, and the sensing configuration and compensation configuration can be used to provide a sensing driving method and a compensation method.

As shown in FIG. 3 , the organic light emitting display device 100 according to the present exemplary embodiments is a sensing configuration for sensing a sub-pixel characteristic value variation (also referred to as a sub-pixel characteristic value change amount), and includes a reference voltage line RVL and A sensing unit 300 that is connected through the second switch SW2, senses a voltage on the reference voltage line RVL that has become a specific voltage state through sensing driving, converts the sensed voltage into a digital value, and outputs sensed data. may include

The sensing unit 300 may be implemented as an analog-to-digital converter (ADC).

Referring to FIG. 3 , sensing data output by the sensing unit 300 may be stored in the memory 310 .

In addition, as shown in FIG. 3 , the organic light emitting display device 100 according to the present exemplary embodiment uses the sensed data output by the sensing unit 300 as a compensation configuration for compensating for sub-pixel characteristic value deviation. Thus, a compensation unit 320 that calculates a compensation value for compensating for the sub-pixel characteristic value deviation may be included.

The compensation value calculated by the compensation unit 320 may be stored in the memory 310 .

The compensator 320 or the controller 140 uses the compensation value calculated by the compensator 320 to change data to be supplied to the corresponding sub-pixel and supplies the changed data to the data driver 120 . Accordingly, sub-pixel characteristic value deviation compensation is actually performed.

For example, the changed data may be generated by adding a compensation value (eg, a threshold voltage or a threshold voltage variation (threshold voltage deviation), etc.) to the original data.

The compensator 320 may be included in the controller 140 .

Hereinafter, a sensing principle of the threshold voltage (or threshold voltage variation) of the driving transistor DRT will be briefly described with reference to FIG. 4 .

4 is a graph illustrating a voltage change of the sensing node Ns or the first node N1 of the driving transistor DRT during the threshold voltage sensing operation of the organic light emitting diode display 100 according to the present exemplary embodiment.

Referring to FIG. 4 , the threshold voltage sensing operation of the organic light emitting diode display 100 according to the present exemplary embodiments may be performed through an initialization step S410 , a voltage following step S420 , and a sensing step S430 . here,

Referring to FIG. 4 , in the initialization step S410 , the first node N1 and the second node N2 of the driving transistor DRT are initialized to the data voltage Vdata and the reference voltage Vref, respectively.

In the initialization step S410 , the switching transistor SWT is turned on and the data voltage Vdata is applied to the second node N2 of the driving transistor DRT. And, the first switch SW1 connecting the reference voltage line RVL and the reference voltage supply node Nref is turned on, and is driven through the reference voltage line RVL and the turned-on sensing transistor SENT. The reference voltage Vref is applied to the first node N1 of the transistor DRT.

Referring to FIG. 4 , in the voltage following step S420 , the first node N1 of the driving transistor DRT is made to float. Accordingly, the voltage of the first node N1 of the driving transistor DRT increases while following the voltage of the second node N2.

The voltage of the first node N1 of the driving transistor DRT rises and becomes saturated after a certain period of time.

The sensing step S430 is a step performed when the voltage of the first node N1 of the driving transistor DRT is saturated due to an increase.

In the sensing step S430 , the second switch SW2 is turned on, and the sensing unit 300 senses the voltage of the reference voltage line RVL.

In this case, the sensed sensing voltage Vsen may be expressed as a known data voltage Vdata and a desired threshold voltage Vth (Vsen=Vdata-Vth).

5 and 6 are diagrams illustrating initial threshold voltage sensing and threshold voltage variation sensing of the organic light emitting diode display 100 according to the present exemplary embodiments.

Referring to FIG. 5 , when the threshold voltage of the driving transistor DRT is first sensed, that is, in the case of initial threshold voltage sensing, according to the threshold voltage sensing operation of FIG. 4 , the voltage sensed by the sensing unit 300 ( Vsen) is Vdata-Vth.

5 , after the threshold voltage Vth of the driving transistor DRT is first sensed, when the driving transistor DRT is further deteriorated, the initial threshold voltage Vth may be changed.

As described above, when the threshold voltage of the driving transistor DRT changes from Vth to Vth' according to the change in the threshold voltage of the driving transistor DRT, that is, the threshold voltage change amount (ΔVth=Vth) of the driving transistor DRT When '-Vth) occurs, in order to sense the threshold voltage change ΔVth of the driving transistor DRT, in the initialization step S410 , the applied to the second node N2 of the driving transistor DRT is applied. The data voltage Vdata' is a voltage obtained by adding a previously sensed threshold voltage (ie, an initial threshold voltage Vth) to Vdata (Vdata'=Vdata+Vth).

According to the threshold voltage sensing operation of FIG. 4 , when the threshold voltage variation is sensed, that is, when the threshold voltage is re-sensed instead of the initial threshold voltage sensing, the voltage Vsen sensed by the sensing unit 300 is expressed by the following Equation 1 and can be expressed together.

In Equation 1, Vth is Vth_memory stored in the memory 310 according to initial sensing, and Vth' is Vth_real, which is an actual threshold voltage of the driving transistor DRT during current sensing.

Therefore, Equation 1 can be expressed again as Equation 2 below.

7 is a diagram illustrating a sensing node Ns or a first node N1 of a driving transistor DRT when a threshold voltage is sensed through one sensing operation in the organic light emitting diode display 100 according to the present exemplary embodiments. It is a diagram showing the voltage change.

In the threshold voltage sensing operation, the voltage following step ( S420 ) takes considerably longer than the initialization step ( S410 ).

Accordingly, in the threshold voltage sensing operation, the voltage change graph of the sensing node Ns or the first node N1 of the driving transistor DRT is, as shown in FIG. 7 , the voltage state in the initialization step S410 is could be ignored.

In FIG. 7 , it is assumed that the initialization voltage Vref applied to the first node N1 of the driving transistor DRT is 0 [V].

Referring to FIG. 7 , when the threshold voltage variation is sensed, that is, when the threshold voltage is re-sensed instead of the initial threshold voltage sensing, the voltage Vsen sensed by the sensing unit 300 may be expressed as Equation 2 above. .

Referring to FIG. 7 , the threshold voltage variation ΔVth may be a positive value or a negative value.

Meanwhile, during the threshold voltage sensing operation, it takes a considerable time for the voltage of the first node N1 of the driving transistor DRT to saturate while rising. For this reason, the total sensing driving time (Ts) required for sensing the threshold voltage is inevitably long.

This is because, when the number of sub-pixels increases according to the high resolution, it takes a very long time (approximately several minutes to several tens of minutes) to sense the threshold voltage of the sub-pixels disposed on the organic light emitting display panel 110 . none. That is, the size of the driving transistor is also reduced to match the small pixel size for realizing high resolution. At this time, due to a decrease in the current capability of the driving transistor, for example, an increase in the charging time of the sensing line capacitor, the increased threshold voltage sensing time is inevitably longer than in the prior art.

Accordingly, as shown in FIG. 8 , the threshold voltage sensing may be performed when a power-off signal of the organic light emitting display device 100 is generated in order not to interfere with the user's viewing.

As such, when the threshold voltage is sensed for the organic light emitting display panel 110 when the power-off signal is generated, there is a disadvantage in that the threshold voltage compensation is not performed in a timely manner.

In addition, when the power-off signal is generated, when the threshold voltage is sensed for the organic light emitting display panel 110, there is a disadvantage in that the threshold voltage cannot be sensed when the power cord is forcibly disconnected.

Accordingly, the present embodiments provide a real-time sensing driving method for threshold voltage real-time capable of sensing the threshold voltage of a driving transistor in a sub-pixel in real time while power is on, for example, during a blank time period. and a sensing and compensation method using the same can be provided.

Herein, during the blank time period, the threshold voltage real-time sensing driving method determines the total sensing driving period required to sense the threshold voltage of the driving transistors in the subpixels of the organic light emitting display panel 110 as the blank time. Time), the corresponding organic light emitting display panel 110 is driven to sense the threshold voltage in real time for several threshold voltage real-time sensing driving periods.

In other words, in order to sense the threshold voltage of the driving transistor in the subpixels of the organic light emitting display panel 110 , there are n (n≥2) times of threshold voltage real-time sensing driving periods, and n times of threshold voltage real-time sensing driving periods. All or some of them may be included in the blank time interval.

FIG. 9 is a diagram for explaining a method of real-time sensing a threshold voltage through real-time sensing driving of the threshold voltage during a blank time period in the organic light emitting diode display 100 according to the present exemplary embodiments. FIG. 10 is a diagram schematically illustrating timing of threshold voltage real-time sensing driving during a blank time period in the organic light emitting diode display 100 according to the present exemplary embodiments.

9 and 10 , in the organic light emitting diode display 100 according to the present exemplary embodiment, while the threshold voltage is sensed over the entire area of the organic light emitting display panel 110 in real time during the blank time period, two or more During the blank time period, there are n threshold voltage real-time sensing driving periods (PSD #1, PSD #2, ... , PSD #n, n≥2) having a value of 2 or more.

In the n-time threshold voltage real-time sensing driving period (PSD #1, PSD #2, ..., PSD #n), during each threshold voltage real-time sensing driving period, in each of at least one sensing target subpixel, a driving transistor ( DRT) is driven for characteristic value sensing (eg, threshold voltage sensing).

That is, in the n-time threshold voltage real-time sensing driving period (PSD #1, PSD #2, ..., PSD #n), during each threshold voltage real-time sensing driving period, each of at least one sensing target sub-pixel, A voltage is increased at the first node N1 of the driving transistor DRT for driving the light emitting diode OLED, and a constant voltage is applied to the second node N1 of the driving transistor DRT.

Referring to FIGS. 9 and 10 , when a threshold voltage sensing for the organic light emitting display panel 110 is performed when a power-off signal is generated as shown in FIG. 8 , when a threshold voltage real time Ts time is required, organic light emitting diodes are emitted. With respect to the threshold voltage sensing of the driving transistor in the necessary (or all) sub-pixels of the display panel 110 , if the time (T1, T2, ..., TN) required for each of the n times of threshold voltage real-time sensing driving is added , which is equal to or similar to Ts time.

By using the threshold voltage real-time sensing driving method during the blank time period described above, it is possible to enable threshold voltage sensing that was impossible while the power is on. That is, by dividing the threshold voltage real-time sensing driving period for the threshold voltage sensing of the driving transistor in the sub-pixels of the organic light emitting display panel 110 into two or more threshold voltage real-time sensing driving periods, while the power is on, that is, blank Even during the time period, it is possible to perform threshold voltage sensing, which requires a long sensing operation, in real time.

11 is a diagram schematically illustrating timing of a threshold voltage real-time sensing operation during a blank time period in the organic light emitting diode display 100 according to the present exemplary embodiments.

Referring to FIG. 11 , the sensing of the threshold voltage of the driving transistor in the subpixels of the organic light emitting display panel 110 is not performed only during the blank time period, but within the subpixels of the organic light emitting display panel 110 during the blank time period. When the threshold voltage sensing of the driving transistor is not completed, the threshold voltage sensing for a partial region of the organic light emitting display panel 110 may be performed even after the power-off signal is generated.

Even when the threshold voltage sensing of the driving transistor in some subpixels of the organic light emitting display panel 110 is performed after the power-off signal is generated, as shown in FIG. 8 , the driving in the subpixels of the organic light emitting display panel 110 is performed. The sensing driving time after power-off may be lower than that of sensing the threshold voltage of the transistor after the power-off signal is generated. Hereinafter, it will be described that the threshold voltage real-time sensing is performed during the blank time period, but as shown in FIG. 11 in this specification, the threshold voltage sensing of the driving transistor in some sub-pixels of the organic light emitting display panel 110 is performed by the power-off signal. A process that is performed after the generation of the threshold voltage may mean real-time sensing of the threshold voltage.

According to this phenomenon, the first threshold voltage real-time sensing driving period to the N-1th threshold voltage real-time sensing driving period among n threshold voltage real-time sensing driving periods (PSD #1, PSD #2, ... , PSD #n) At the end of each period, the voltage of the first node N1 of the driving transistor DRT is in a non-saturated state, and n threshold voltage real-time sensing driving periods PSD #1, PSD #2, ... , PSD #n), the voltage of the first node N1 of the driving transistor DRT is saturated in the last nth threshold voltage real-time sensing driving period.

As described above, the sensing driving (threshold voltage sensing driving) that causes the first node N1 of the driving transistor DRT to be in a voltage state reflecting the threshold voltage is divided into n times of threshold voltage real-time sensing driving. , the voltage rise gradually decreases as the threshold voltage real-time sensing driving period proceeds later, and the voltage of the first node N1 of the driving transistor DRT finally becomes saturated in the last threshold voltage real-time sensing driving period.

Hereinafter, with reference to FIG. 12 , a timing at which threshold voltage sensing driving is performed n times for threshold voltage sensing of driving transistors in subpixels of the organic light emitting display panel 110 will be described.

12 is a timing diagram illustrating the timing of the threshold voltage sensing operation of the organic light emitting display device 100 according to the present exemplary embodiments for threshold voltage sensing of the driving transistor in the subpixels of the organic light emitting display panel 110 in real time n times. It is also an example.

Meanwhile, in the organic light emitting display device 100 according to the present embodiments, as shown in FIG. 12 , each of n threshold voltage real-time sensing operations is performed for a blank time based on the vertical synchronization signal VSYNC. can proceed while

Therefore, in the n-time threshold voltage real-time sensing driving period (PSD #1, PSD #2, ... , PSD #n) for one sub-pixel, each threshold voltage real-time sensing driving period is a blank time period. can be included in

The example of FIG. 12 illustrates a case in which four threshold voltage real-time sensing driving periods PSD #1, PSD #2, PSD #3, and PSD #4 are included in four blank time periods within four frame times.

As described above, since the n times of the threshold voltage real-time sensing operation is performed for each blank time interval, the n times of the threshold voltage real-time sensing operation do not affect the image operation.

13 is a conceptual diagram of real-time sensing of a threshold voltage in a threshold voltage real-time sensing driving in the organic light emitting display device 100 according to the present exemplary embodiments. 14 is a graph illustrating a voltage change of a sensing node when the threshold voltage is sensed in real time in the threshold voltage real-time sensing driving of FIG. 13 .

First, during threshold voltage sensing driving, the first node N1 of the driving transistor DRT is initialized to the initialization voltage Vref or Vini, and then floats to increase the voltage.

Accordingly, as shown in FIG. 13 , an arbitrary i-1 (i=2, ... , n)-th threshold voltage real-time sensing driving period (PSD #i-1) starts at a time point (initialization step S410) )), the first node N1 of the driving transistor DRT is initialized to the corresponding initialization voltage V1(i-1), and then the voltage rises according to floating.

At the end of the real-time sensing driving period PSD #i-1, V1B(i-1) corresponding to the voltage of the first node N1 of the driving transistor DRT corresponds to the saturation voltage .

Referring to FIG. 13 , the voltage change of the first node N1 of the driving transistor DRT according to the threshold voltage real-time sensing driving will be described with reference to FIG. 14 . However, in FIG. 14 , when a positive threshold voltage change amount (Positive ΔVth) is present and a negative threshold voltage change amount (Negative ΔVth) is present, a positive threshold voltage change amount (Positive ΔVth) and a negative threshold voltage change amount (Negative ΔVth) The voltage change is shown for the case of having the threshold voltage change amount ΔVth between .

Referring to FIG. 14 , when the threshold voltage real-time sensing driving is in progress for threshold voltage sensing for one sub-pixel, the i-1th threshold voltage real-time sensing driving period PSD #i-1 starts, In the initialization step, an initialization voltage Vini corresponding to V1(i-1) is applied to the first node N1 of the driving transistor DRT, and the second node N2 of the driving transistor DRT is applied. A constant voltage (Vdata+Vini) corresponding to V2(i-1) is applied.

Thereafter, the first node N1 of the driving transistor DRT floats, so that the voltage of the first node N1 of the driving transistor DRT rises. After the length T1 of the i-1th threshold voltage real-time sensing driving section PSD #i-1 has elapsed, the i-1th threshold voltage real-time sensing driving section PSD #i-1 ends. , the voltage of the first node N1 of the driving transistor DRT becomes V1B(i-1).

At the end of the i-1th threshold voltage real-time sensing driving period PSD #i-1, V1B(i-1) corresponding to the voltage of the first node N1 of the driving transistor DRT is the saturation voltage ( Saturation Voltage).

Accordingly, at the end of the i-1th threshold voltage real-time sensing driving period PSD #i-1, the sensing unit 300 generates V1B ( i-1) is finally sensed through the reference voltage line RVL or the sensing node Ns. In this case, the sensed voltage Vsen may be expressed in a voltage form including a threshold voltage Vth or a threshold voltage variation (ΔVth, threshold voltage deviation).

The compensator 320 may compensate a threshold voltage or a threshold voltage variation (threshold voltage deviation) of the driving transistor DRT based on the sensed voltage Vsen.

13 and 14, the first node N1 of the driving transistor DRT is initialized to the initialization voltage Vref or Vini in the i-1th threshold voltage real-time sensing driving period PSD #i-1, and then floating The voltage rise occurs, and at the end of the real-time sensing driving period PSD #i-1, V1B(i-1) corresponding to the voltage of the first node N1 of the driving transistor DRT is a saturation voltage (Saturation Voltage) is reached. Threshold voltage sensing for one subpixel is not completed in the i-1th threshold voltage real-time sensing driving period (PSD #i-1) because one blank time period is short or another compensation operation needs to be performed during the blank time period. can't

Accordingly, by dividing the sensing driving period for one sub-pixel into two or more blank time periods, threshold voltage sensing, which requires long-time sensing driving, can be performed in real time even while the power is turned on. Hereinafter, a process of dividing a sensing driving period for one subpixel into two or more blank time periods will be described with reference to FIGS. 15 and 16 .

15 is a conceptual diagram of a threshold voltage real-time sensing driving in the organic light emitting display device 100 according to the present exemplary embodiments. FIG. 16 is a graph illustrating a voltage change of the sensing node Ns when the threshold voltage real-time sensing operation is performed n times during the threshold voltage real-time sensing operation of FIG. 15 . Here, the voltage change of the sensing node Ns may be a voltage change of the reference voltage line RVL, or may be a voltage change of the first node N1 of the driving transistor DRT.

First, during threshold voltage sensing driving, the first node N1 of the driving transistor DRT is initialized to the initialization voltage Vref or Vini, and then floats to increase the voltage.

Accordingly, as shown in FIG. 15 , an arbitrary i-1 (i=2, ... , n)-th threshold voltage real-time sensing driving period (PSD #i-1) starts at a time point (initialization step S410). )), the first node N1 of the driving transistor DRT is initialized to the corresponding initialization voltage V1(i-1), and then the voltage rises according to the floating.

At the first node N1 of the driving transistor DRT, a voltage rise occurs, and then the i-1 (i=2, ... , n)th threshold voltage real-time sensing driving period PSD #i-1 ends. At a time point (middle point in the time interval corresponding to the voltage following step S420 ), the increased voltage V1B(i-1) becomes (V1(i-1)<V1B(i-1)).

During each threshold voltage real-time sensing driving period, data voltages applied to the second node N2 (eg, a gate node) of the driving transistor DRT are constant voltages and are equal to each other.

15 , a constant voltage applied to the second node N2 of the driving transistor DRT during an arbitrary i (i=2, ... , n)th threshold voltage real-time sensing driving period PSD #i (V2(i)) is a constant voltage V2(i-1) applied to the second node N2 of the driving transistor DRT during the previous i-1th threshold voltage real-time sensing driving period PSD #i-1 )) (V2(i-1)=V2(i)).

As above, at the end of the i-1th threshold voltage real-time sensing driving period PSD #i-1, the potential difference V21 between the second node N1 and the first node N1 of the driving transistor DRT is , in order to maintain the same potential difference V21 between the second node N1 and the first node N1 of the driving transistor DRT at the start of the i-th threshold voltage real-time sensing driving period PSD #i, The initialization voltage V1 (i) applied to the first node N1 of the driving transistor DRT at a time point at which the i-th threshold voltage real-time sensing driving period PSD #i starts (a time point corresponding to the initialization step S410) )) at the end of the previous i-1th threshold voltage real-time sensing driving period PSD #i-1 (the middle point of the time period corresponding to the voltage following step S420), the driving transistor DRT It must be equal to the increased voltage V1B(i-1) of the first node N1 of .

According to this, the initialization voltage ( V1(i)) is the first time of the driving transistor DRT at the start of the previous i-1th threshold voltage real-time sensing driving period PSD #i-1 (a time point corresponding to the initialization step S410). It may be different from the initialization voltage V1(i-1) applied to the first node N1 (V1(i)≠V1(i-1)).

Specifically, the initialization applied to the first node N1 of the driving transistor DRT at the start of the i-th threshold voltage real-time sensing driving period PSD #i (the time point corresponding to the initialization step S410) The voltage V1(i) is the driving transistor DRT at the start of the previous i-1th threshold voltage real-time sensing driving period PSD #i-1 (a time point corresponding to the initialization step S410). It may be higher than the initialization voltage V1(i-1) applied to the first node N1 (V1(i)>V1(i-1)).

The constant voltage of the second node N2 of the driving transistor DRT is fixed, and instead, the initialization voltage applied to the first node N1 of the driving transistor DRT at the start of each threshold voltage real-time sensing driving period is applied. However, the threshold voltage to be newly started is adjusted differently from the initializing voltage applied to the first node N1 of the driving transistor DRT at the start of the real-time sensing driving period to the driving transistor at the end of the previous threshold voltage real-time sensing driving period. By adjusting the voltage to be equal to the raised voltage of the first node N1 of the DRT), a state between the threshold voltage real-time sensing operations can be maintained (V21 is maintained). Accordingly, the n-times of the threshold voltage real-time sensing operation is actually performed separately in time, but may be performed as if a single sensing operation.

When n=4, the voltage change of the first node N1 of the driving transistor DRT according to the threshold voltage real-time sensing operation 4 times will be described with reference to FIG. 14 . However, in FIG. 16 , when a positive threshold voltage change amount (Positive ΔVth) is present and a negative threshold voltage change amount (Negative ΔVth) is obtained, a positive threshold voltage change amount (Positive ΔVth) and a negative threshold voltage change amount (Negative ΔVth) The voltage change is shown for the case of having the threshold voltage change amount ΔVth between .

Referring to FIG. 16 , during the four threshold voltage real-time sensing driving periods (PSD #1, PSD #2, PSD #3, PSD #4), the same constant voltage ( Vdata+Vini) is applied. That is, V2(1)=V2(2)=V2(3)=V2(4).

Referring to FIG. 16 , when a first threshold voltage real-time sensing driving period (PSD #1) starts, assuming that the threshold voltage real-time sensing driving is performed 4 times for threshold voltage sensing for one sub-pixel, initialization is performed As the step progresses, the initialization voltage Vini corresponding to V1(1) is applied to the first node N1 of the driving transistor DRT, and V2(1) is applied to the second node N2 of the driving transistor DRT. ), a constant voltage (Vdata+Vini) is applied.

Thereafter, the first node N1 of the driving transistor DRT floats, so that the voltage of the first node N1 of the driving transistor DRT rises. After the length T1 of the first threshold voltage real-time sensing driving period PSD #1 has elapsed, the first threshold voltage real-time sensing driving period PSD #1 ends. The voltage of one node N1 becomes V1B(1).

After the first threshold voltage real-time sensing driving period (PSD #1) ends, the image driving period (VD) proceeds, and when the image driving period (VD) ends, the second threshold voltage real-time sensing driving period (PSD #2) This starts again.

When the second threshold voltage real-time sensing driving period PSD #2 starts, an initialization step proceeds, and a constant voltage Vdata+Vini corresponding to V2(2) is applied to the second node N2 of the driving transistor DRT. equally authorized.

Meanwhile, an initialization voltage V1(2) is applied to the first node N1 of the driving transistor DRT. The initialization voltage V1(2) is applied at the end of the first threshold voltage real-time sensing driving period PSD #1. It is equal to the voltage V1B(1) of the first node N1 of the driving transistor DRT (V1(2)=V1B(1)).

Accordingly, at the end of the first threshold voltage real-time sensing driving period PSD #1 and the beginning of the second threshold voltage real-time sensing driving period PSD #2, the second node N2 of the driving transistor DRT and the potential difference V21 between the first node N1 and the first node N1 is maintained.

Thereafter, the first node N1 of the driving transistor DRT floats, so that the voltage of the first node N1 of the driving transistor DRT rises. After a period of time T2 of the second threshold voltage real-time sensing driving period PSD #2 has elapsed, the second threshold voltage real-time sensing driving period PSD #2 ends. The voltage of one node (N1) becomes V1B(2).

After the second threshold voltage real-time sensing driving section (PSD #2) ends, the image driving section (VD) proceeds, and when the image driving section (VD) ends, the third threshold voltage real-time sensing driving section (PSD #3) This starts again.

When the third threshold voltage real-time sensing driving period (PSD #3) starts, an initialization step proceeds, and a constant voltage (Vdata+Vini) corresponding to V2(3) is applied to the second node N2 of the driving transistor DRT. equally authorized.

On the other hand, the initialization voltage V1(3) is applied to the first node N1 of the driving transistor DRT. The initialization voltage V1(3) is applied at the end of the second threshold voltage real-time sensing driving period PSD #2. It is equal to the voltage V1B(2) of the first node N1 of the driving transistor DRT (V1(3)=V1B(2)).

Accordingly, at the end of the second threshold voltage real-time sensing driving period PSD #2 and the beginning of the third threshold voltage real-time sensing driving period PSD #3, the second node N2 of the driving transistor DRT and the potential difference V21 between the first node N1 and the first node N1 is maintained.

Thereafter, the first node N1 of the driving transistor DRT floats, so that the voltage of the first node N1 of the driving transistor DRT rises. After a period of time T3 of the third threshold voltage real-time sensing driving period PSD #3 has elapsed, the third threshold voltage real-time sensing driving period PSD #3 ends. The voltage at node 1 (N1) becomes V1B (3).

After the third threshold voltage real-time sensing driving period (PSD #3) ends, the image driving period (VD) proceeds, and when the image driving period (VD) ends, the fourth threshold voltage real-time sensing driving period (PSD #4) This starts again.

When the fourth threshold voltage real-time sensing driving period (PSD #4) starts, an initialization step proceeds, and a constant voltage (Vdata+Vini) corresponding to V2(4) is applied to the second node N2 of the driving transistor DRT. equally authorized.

Meanwhile, an initialization voltage V1(4) is applied to the first node N1 of the driving transistor DRT. The initialization voltage V1(4) is applied at the end of the third threshold voltage real-time sensing driving period PSD #3. It is equal to the voltage V1B(3) of the first node N1 of the driving transistor DRT (V1(4)=V1B(3)).

Accordingly, at the end of the third threshold voltage real-time sensing driving period PSD #3 and the beginning of the fourth threshold voltage real-time sensing driving period PSD #4, the second node N2 of the driving transistor DRT and the potential difference V21 between the first node N1 and the first node N1 is maintained.

Thereafter, the first node N1 of the driving transistor DRT floats, so that the voltage of the first node N1 of the driving transistor DRT rises. After a period of time T4 of the fourth threshold voltage real-time sensing driving period PSD #4 has elapsed, the fourth threshold voltage real-time sensing driving period PSD #4 ends. The voltage at node 1 (N1) becomes V1B (4).

At the end of the last fourth threshold voltage real-time sensing driving period (PSD #4), V1B(4) corresponding to the voltage of the first node N1 of the driving transistor DRT corresponds to the saturation voltage. do.

Accordingly, the sensing unit 300 at the end of the fourth threshold voltage real-time sensing driving period PSD #4 is based on V1B(4) corresponding to the saturation voltage of the first node N1 of the driving transistor DRT. Finally, sensing is performed through the voltage line RVL or the sensing node Ns. In this case, the sensed voltage Vsen may be expressed in a voltage form including a threshold voltage Vth or a threshold voltage variation (ΔVth, threshold voltage deviation).

The compensator 320 may compensate a threshold voltage or a threshold voltage variation (threshold voltage deviation) of the driving transistor DRT based on the sensed voltage Vsen.

As described above, in the organic light emitting display device 100 according to the present embodiments, a characteristic value (eg, a threshold voltage) or a change amount of a characteristic value (eg, a threshold voltage) of the driving transistor DRT through the threshold voltage real-time sensing driving two or more times A method that can sense the amount of change in real time even while the power is on has been described.

17 is a diagram conceptually illustrating sensing and compensation using threshold voltage real-time sensing driving of the organic light emitting diode display 100 according to the present exemplary embodiments.

Referring to FIG. 17 , in the organic light emitting display device 100 according to the present exemplary embodiments, the organic light emitting display panel 110 in which a plurality of sub-pixels each including an organic light emitting diode (OLED) and a driving transistor (DRT) are disposed. ) and, during the blank time period, the threshold voltage real-time sensing operation (PSD #1, PSD #2..., PSD #n, n is a natural number greater than or equal to 2) for the same sub-pixel (SP) is performed two or more times. and a sensing unit 300 sensing the voltage of the first node N1 (eg, a source node or a drain node) of the driving transistor DRT in the subpixel SP twice or more.

When the sensing unit 300 senses the voltage of the first node N1 of the driving transistor DRT twice or more, each threshold voltage real-time sensing driving period PSD #1, PSD #2... , PSD #n ) means to sense at the end point.

In this case, the last sensed voltage among the two or more times of sensing becomes the final voltage capable of sensing the characteristic value or the change amount of the characteristic value of the driving transistor DRT.

An image driving section VD may exist between each section in which the sensing unit 300 senses two or more times (a threshold voltage real-time sensing section).

As described above, by dividing the sensing twice or more during two or more blank time periods for the same subpixel SP, sensing that was impossible during one blank time period because the sensing time is too long may be enabled.

Referring to FIG. 17 , the compensator 320 may compensate for a characteristic value or a characteristic value change amount of the driving transistor DRT based on the last sensed voltage among voltages sensed two or more times.

As described above, as sensing, which was impossible during image driving because the sensing time is too long, becomes possible during image driving, compensation may also be performed at a faster timing in real time.

As described above with reference to FIG. 11 , when the characteristic value or the change amount of the driving transistor DRT cannot be sensed for two or more blank time periods for the same subpixel SP during the blank time period, the remaining power-off signal is generated. Thereafter, the characteristic value or the change amount of the other driving transistors is sensed with respect to the same subpixel SP, and the characteristic value or the change amount of the characteristic value of the driving transistor may be compensated when the next power is turned on.

19 to 23 show the sequence of real-time sensing of the threshold voltage for the threshold voltage of the entire region of the organic light emitting display panel during the blank time period.

As shown in FIG. 19 , in the organic light emitting display panel 110 , two or more reference voltage lines RVL are disposed in a first direction (row direction, horizontal direction in FIG. 19 ), and are connected to each reference voltage line. A first node of the two or more driving transistors may be connected in a column direction, and a first node of one driving transistor may be connected in a second direction (a column direction (vertical direction in FIG. 19 )). In this case, the reference voltage Vref is applied through two or more reference voltage lines RVL in a row direction (horizontal direction in FIG. 19 ). As shown in Fig. 16, during the threshold voltage real-time sensing driving period (PSD #1, PSD #2, PSD #3, PSD #4) of the four times, the column direction driving transistors sequentially connected to each reference voltage line are sequentially removed. The threshold voltage for one node can be separated in time and sensed.

On the other hand, since the blank time is short, as shown in Fig. 16, during the four threshold voltage real-time sensing driving periods (PSD #1, PSD #2, PSD #3, PSD #4), the column direction driving transistors connected to each reference voltage line It may not be possible to separate the threshold voltage for the first node in time and sense it. In this case, as shown in FIG. 20 , some of the n-time threshold voltage real-time sensing driving periods, for example, 4 threshold voltage real-time sensing driving periods (PSD #1, PSD #2, PSD #3, PSD #4) During the time period, the threshold voltage for the first node of some of the driving transistors in the column direction connected to each reference voltage line is separated and sensed, and another part of the n-time threshold voltage real-time sensing driving period, for example, the threshold voltage of 4 times During the real-time sensing driving period (PSD #5, PSD #6, PSD #7, PSD #8), the threshold voltages for the first nodes of other portions of the driving transistors in the column direction connected to each reference voltage line are separated in time for sensing. can do.

In the organic light emitting display panel 110 , two or more reference voltage lines RVL are disposed in a column direction, a first node of two or more driving transistors is connected to each reference voltage line in a column direction, and two or more driving transistors are formed in a row direction. The first node may be connected. For example, as shown in FIG. 21 , when the first node of two or more driving transistors is connected to both sides of each reference voltage line RVL, during some of the n threshold voltage real-time sensing driving periods, for example, 4 times During the threshold voltage real-time sensing driving period (PSD #1, PSD #2, PSD #3, PSD #4) of each reference voltage line (RVL) in the row direction (left in FIG. 21), the driving transistor in the column direction is connected Threshold voltages for some of the first nodes may be separated in time and sensed. During other parts of the n-time threshold voltage real-time sensing driving periods, for example, during the 4 threshold voltage real-time sensing driving periods (PSD #5, PSD #6, PSD #7, PSD #8), each reference voltage line RVL ), the threshold voltages for the first nodes of some of the driving transistors in the column direction connected to the other side (the right side in FIG. 21 ) in the row direction may be separated in time to be sensed.

At this time, as shown in FIG. 22, both sub-pixels in the row direction of each reference voltage line RVL are alternately separated in time during the threshold voltage real-time sensing driving period PSD #1 to PSD #8 eight times, and the sensing may be performed. there is.

Since the blank time is short, the threshold voltage for the first node of the driving transistors in the column direction connected to one side of the row direction of each reference voltage line during the threshold voltage real-time sensing driving period (PSD #1 to PSD #8) is calculated in time. It may not be possible to separate and sense it. 23, during some of the n-time threshold voltage real-time sensing driving periods, for example, during the 4 threshold voltage real-time sensing driving periods (PSD #1, PSD #3, PSD #5, PSD #7) Threshold voltages of some of the driving transistors in the column direction connected to one side of the row direction of each reference voltage line may be separated in time to be sensed. Rows of each reference voltage line during another part of the n-time threshold voltage real-time sensing driving period, for example, during the 4 threshold voltage real-time sensing driving period (PSD #2, PSD #4, PSD #6, PSD #8) Threshold voltages of some of the driving transistors in the column direction connected to the other side of the direction may be separated in time to be sensed.

Similarly, the row direction of each reference voltage line during the other part of the n-time threshold voltage real-time sensing driving periods and during the 4 threshold voltage real-time sensing driving periods (PSD #9, PSD #11, PSD #13, PSD #15) Threshold voltages with respect to the first node of other portions of the driving transistors in the column direction connected to one side may be sensed by separating in time. During another part of the n-time threshold voltage real-time sensing driving period, the other in the row direction of each reference voltage line during the 4 threshold voltage real-time sensing driving period (PSD #10, PSD #12, PSD #14, PSD #16) Threshold voltages for the first nodes of other portions of the driving transistors in the column direction connected to the ?

The sequence of sensing the threshold voltage in real time during the blank time period with respect to the threshold voltage of the entire region of the organic light emitting display panel has been described with reference to FIGS. 19 to 23 , but various combinations thereof are possible. In addition, when a power-off signal is generated while sensing the threshold voltage of the entire region of the organic light emitting display panel described with reference to FIGS. 19 to 23 during the blank time period, the remaining sensing operation is performed as described with reference to FIGS. 11 and 18 . may be performed after the power-off signal is generated.

21 to 23 illustrate a case in which two sub-pixels are connected to each reference voltage line RVL, but 3 or more sub-pixels are connected to each reference voltage line RVL. The sensing operation shown in FIGS. 21 to 23 may be performed four times.

According to the threshold voltage real-time sensing driving method described above, by performing the sensing two or more times for the same sub-pixel SP, sensing, which was impossible during image driving because the sensing time is too long, can be made possible even during image driving.

According to the present exemplary embodiments as described above, it is possible to provide the organic light emitting diode display 100 and a driving method thereof, which allow the characteristic value sensing operation between driving transistors to be performed in real time while the power is turned on.

Also, according to the present exemplary embodiments, it is possible to provide the organic light emitting display device 100 and a driving method thereof that allow a characteristic value sensing operation between driving transistors to be performed in real time while an image is being driven.

The above description and the accompanying drawings are merely illustrative of the technical spirit of the present invention, and those of ordinary skill in the art to which the present invention pertains can combine configurations within a range that does not depart from the essential characteristics of the present invention. , various modifications and variations such as separation, substitution and alteration will be possible. Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to explain, and the scope of the technical spirit of the present invention is not limited by these embodiments. The protection scope of the present invention should be construed by the following claims, and all technical ideas within the scope equivalent thereto 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 driving unit
130: gate driver
140: controller

Claims (15)

an organic light emitting display panel in which a plurality of data lines and a plurality of gate lines are disposed, and a plurality of subpixels are disposed;
a data driver driving the plurality of data lines;
a gate driver driving the plurality of gate lines; and
a controller for controlling the data driver and the gate driver;
In order to sense the threshold voltage of a driving transistor in the subpixels of the organic light emitting display panel, n (n≥2) times of threshold voltage real-time sensing driving periods exist, and all of the n times of threshold voltage real-time sensing driving periods are Or part of it is included in the blank time period,
During the n-th threshold voltage real-time sensing driving period, in each of the at least one sensing target subpixel, a voltage rises at the first node of the driving transistor for driving the organic light emitting diode and corresponds to the gate electrode of the driving transistor A constant voltage is applied to the second node,
At the start of the nth threshold voltage real-time sensing period among the n-times of the threshold voltage real-time sensing driving periods, the n-1th threshold voltage real-time sensing period among the n-th real-time sensing periods of the threshold voltage is provided in the first node. An organic light emitting display device in which the voltage applied to the first node is applied as an initialization voltage at the time of termination. According to claim 1,
When a part of the n-time threshold voltage real-time sensing driving period is included in the blank time period,
The remaining of the n-th threshold voltage real-time sensing driving sections exist after a power-off signal is generated. According to claim 1,
During each threshold voltage real-time sensing driving period, in each of the at least one sensing target subpixel, a voltage rises at the first node of the driving transistor for driving the organic light emitting diode to be saturated. delete According to claim 1,
During the first threshold voltage real-time sensing driving period to the n-1 th threshold voltage real-time sensing driving period among the n-th threshold voltage real-time sensing driving period, the voltage of the first node of the driving transistor is not saturated even though the voltage is increased. ,
In an nth threshold voltage real-time sensing driving period, the voltage of the first node of the driving transistor is saturated. According to claim 1,
a sensing unit configured to sense the voltage of the first node of the driving transistor at the end of each threshold voltage real-time sensing driving period; and
and a memory configured to store data on the voltage sensed at the first node of the driving transistor at the end of each threshold voltage real-time sensing driving period. According to claim 1,
Compensating for the threshold voltage or threshold voltage variation of the driving transistor based on the sensed voltage of the first node of the driving transistor at the end of the last threshold voltage real-time sensing driving period among the n times of the threshold voltage real-time sensing driving periods The organic light emitting display device further comprising a compensator. According to claim 1,
In the organic light emitting display panel, two or more reference voltage lines are disposed in a first direction, a first node of two or more driving transistors is connected to each reference voltage line in a first direction, and a first node of one driving transistor is disposed in a second direction. is connected,
An organic light emitting diode display for time-segmenting and sensing threshold voltages for first nodes of the driving transistors sequentially connected to the respective reference voltage lines in a first direction during the n-th threshold voltage real-time sensing driving period. According to claim 1,
In the organic light emitting display panel, two or more reference voltage lines are disposed in a first direction, a first node of two or more driving transistors is connected to each reference voltage line in a first direction, and a first node of one driving transistor is disposed in a second direction. is connected,
During some of the nth threshold voltage real-time sensing driving periods, the threshold voltages for some first nodes of the driving transistors in the first direction connected to each reference voltage line are separated in time and sensed, and the nth threshold voltage real-time sensing is performed. An organic light emitting diode display for time-segmenting and sensing threshold voltages for first nodes of other portions of column-direction driving transistors connected to each reference voltage line during another part of driving periods. According to claim 1,
In the organic light emitting display panel, two or more reference voltage lines are disposed in a first direction, a first node of two or more driving transistors is connected to each reference voltage line in a first direction, and a first node of two or more driving transistors is disposed in a second direction. is connected,
During some of the n-th threshold voltage real-time sensing driving periods, a threshold voltage for a first node of a portion of the driving transistors in the first direction connected to one side of the second direction of each reference voltage line is temporally separated and sensed, and the n-th threshold voltage real-time sensing During another part of the driving period, the threshold voltage for the first node of the other part of the driving transistors in the first direction connected to the other side of the second direction of each reference voltage line is temporally separated and sensed organic light emitting display device. According to claim 1,
In the organic light emitting display panel, two or more reference voltage lines are disposed in a first direction, a first node of two or more driving transistors is connected to each reference voltage line in a first direction, and a first node of two or more driving transistors is disposed in a second direction. is connected,
During some of the n-th threshold voltage real-time sensing driving periods, the threshold voltages for the first nodes of some of the driving transistors in the first direction connected to one side of the second direction of each reference voltage line are separated in time and sensed,
During the other part of the n-time threshold voltage real-time sensing driving period, the threshold voltage for the first node of some of the driving transistors in the first direction connected to the other side of the second direction of each reference voltage line is separated in time and sensed,
During the other part of the n-th threshold voltage real-time sensing driving period, the threshold voltage for the first node of the other part of the driving transistors in the first direction connected to one side of the second direction of each reference voltage line is temporally separated and sensed, ,
The threshold voltage for the first node of the other part of the driving transistors in the first direction connected to the other side of the second direction of each reference voltage line during another part of the n-th threshold voltage real-time sensing driving period is separated in time for sensing organic light emitting display device. an organic light emitting display panel in which a plurality of sub-pixels including an organic light emitting diode and a driving transistor are disposed; and
A sensing unit configured to sense a threshold voltage of a driving transistor in subpixels of the organic light emitting display panel during n (n≥2) times of threshold voltage real-time sensing driving periods, all or part of which is included in the blank time period,
During the n-th threshold voltage real-time sensing driving period, in each of the at least one sensing target subpixel, a voltage rises at the first node of the driving transistor for driving the organic light emitting diode and corresponds to the gate electrode of the driving transistor A constant voltage is applied to the second node,
At the start of the nth threshold voltage real-time sensing period among the n-times of the threshold voltage real-time sensing driving periods, the n-1th threshold voltage real-time sensing period among the n-th real-time sensing periods of the threshold voltage is provided in the first node. An organic light emitting display device in which the voltage applied to the first node is applied as an initialization voltage at the time of termination. 13. The method of claim 12,
When a part of the n-time threshold voltage real-time sensing driving period is included in the blank time period,
The remaining of the n-th threshold voltage real-time sensing driving sections exist after a power-off signal is generated. 13. The method of claim 12,
During each threshold voltage real-time sensing driving period, in each of the at least one sensing target subpixel, a voltage rises at the first node of the driving transistor for driving the organic light emitting diode to be saturated. delete

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