KR20200032508A - Driving circuit, organic light emitting display device, and driving method - Google Patents

Abstract

Embodiments of the present invention relate to a driving circuit, an organic light emitting display device, and a driving method and, more specifically, to a driving circuit capable of sensing a threshold voltage of a transistor in real time while driving an image and further simultaneously sensing a threshold voltage and mobility in real time, an organic light emitting display device, and a driving method. According to the embodiments of the present invention, a change in a threshold voltage may be immediately compensated while driving an image and time or number of times required for a sensing driving process may be reduced by sensing the threshold voltage and mobility at the same time in the same sensing driving process.

Description

DRIVING CIRCUIT, ORGANIC LIGHT EMITTING DISPLAY DEVICE, AND DRIVING METHOD}

The present invention relates to a driving circuit, an organic light emitting display device and a driving method.

Recently, an organic light emitting display device, which has been spotlighted as a display device, has an advantage that a response speed is fast and luminous efficiency, luminance, and viewing angle are large by using an organic light emitting diode (OLED) that emits light by itself.

The organic light emitting display device arranges a subpixel including an organic light emitting diode and a driving transistor for driving the same in a matrix form, and controls the brightness of the subpixels selected by the scan signal according to data grayscale.

In the case of the organic light emitting display device, an organic light emitting diode and a driving transistor for driving the organic light emitting diode are disposed in each subpixel defined in the display panel, and the characteristic values of the driving transistor in each subpixel (eg, threshold voltage and mobility) are driving time Depending on, or due to the difference in the driving time of each sub-pixel, variation in characteristic values between transistors may occur. For this reason, luminance variation (luminance non-uniformity) between sub-pixels may occur, and image quality may deteriorate.

In the case of the conventional organic light emitting display device, in order to solve the luminance deviation between sub-pixels, sensing and compensation techniques have been proposed to sense and compensate characteristics deviation between driving transistors. However, due to various conditions, a situation in which normal sensing driving cannot be performed or an accurate sensing value cannot be obtained due to a lack of sensing time, in this case, a situation in which image quality may also be deteriorated may occur. .

An object of the embodiments of the present invention is to provide a driving circuit, an organic light emitting display device and a driving method that enable accurate sensing and compensation while reducing the time required for sensing.

In addition, another object of embodiments of the present invention is to provide a driving circuit, an organic light emitting display device and a driving method capable of sensing a threshold voltage of a transistor in real time during image driving.

In addition, another object of embodiments of the present invention is to provide a driving circuit, an organic light emitting display device and a driving method capable of simultaneously sensing the threshold voltage and mobility of a transistor while driving an image.

In one aspect, embodiments of the present invention, a plurality of data lines and a plurality of gate lines are arranged, a plurality of reference voltage lines are arranged, a plurality of sub-pixels are arranged a display panel, and driving a plurality of data lines An organic light emitting display device including a data driving circuit and a gate driving circuit driving a plurality of gate lines can be provided.

The plurality of subpixels includes an organic light emitting diode, a driving transistor for driving the organic light emitting diode, a first transistor electrically connected between a first node of the driving transistor and a corresponding data line among the plurality of data lines, and the driving transistor. A second transistor electrically connected between the second node and a corresponding reference voltage line among the plurality of reference voltage lines, and a capacitor electrically connected between the first node and the second node of the driving transistor.

The organic light emitting display device includes a reference switch for sensing driving electrically connected between a reference voltage supply node and a reference voltage line, an analog-to-digital converter for sensing the voltage of the reference voltage line, and an electrical between the reference voltage line and the analog digital converter. It may further include a connected sampling switch.

The drain node or source node of the second transistor included in any first subpixel among the plurality of subpixels may be electrically connected to the first reference voltage line among the plurality of reference voltage lines.

The drain node or source node of the first transistor included in the first subpixel may be electrically connected to the first data line among the plurality of data lines.

During the initialization period during the first sensing driving period, the first reference voltage may be applied to the first reference voltage line. In addition, during the initialization period of the first sensing driving period, the data voltage for the first sensing driving may be applied to the first data line.

During the first sensing driving period, during the predetermined boosting time after the initialization period, the voltage of the first reference voltage line may increase from the first reference voltage.

During the first sensing driving period, when the boosting time has elapsed after the initialization period, the sampling switch is turned on so that the first reference voltage line is electrically connected to the analog digital converter, and the analog digital converter is the voltage of the first reference voltage line. A first sensing value may be output by sensing.

During the initialization period of the second sensing driving period different from the first sensing driving period, a second reference voltage different from the first reference voltage may be applied to the first reference voltage line. In addition, during the initialization period of the second sensing driving period, the second sensing driving data voltage equal to the first sensing driving data voltage may be applied to the first data line.

During the boosting time after the initialization period during the second sensing driving period, the voltage may increase in the first reference voltage line from the second reference voltage.

During the second sensing driving period, when the boosting time elapses after the initialization period, the sampling switch is turned on so that the first reference voltage line is electrically connected to the analog digital converter, and the analog digital converter is the voltage of the first reference voltage line. A second sensing value may be output by sensing.

Based on the first sensing value obtained during the first sensing driving period and the second sensing value obtained during the second sensing driving period, the gain and offset of the data voltage for driving the image supplied to the first subpixel may be changed.

The gain and offset of the data voltage for driving the image supplied to the first subpixel may be changed according to a change in the mobility and threshold voltage of the driving transistor included in the first subpixel.

Each of the first sensing driving period and the second sensing driving period may be included in different blank periods.

In another aspect, embodiments of the present invention include a display panel in which a plurality of data lines and a plurality of gate lines are arranged, a plurality of reference voltage lines are arranged, and a plurality of subpixels are arranged; A data driving circuit driving a plurality of data lines; And a gate driving circuit for driving the plurality of gate lines, the plurality of sub-pixels being one of an organic light-emitting diode, a driving transistor for driving the organic light-emitting diode, a first node of the driving transistor, and a plurality of data lines A first transistor electrically connected between data lines, a second transistor electrically connected between a second node of the driving transistor and a corresponding reference voltage line among a plurality of reference voltage lines, and between a first node and a second node of the driving transistor It is possible to provide a driving method of an organic light emitting display device including a capacitor electrically connected to.

The driving method includes a first sensing driving step of supplying a first reference voltage to a first reference voltage line electrically connected to a drain node or a source node of a second transistor included in any first subpixel among a plurality of subpixels; After the first sensing driving step, the second sensing voltage supplying a second reference voltage different from the first reference voltage to the first reference voltage line electrically connected to the drain node or the source node of the second transistor included in the first subpixel. It may include a driving step.

The drain node or source node of the first transistor included in the first subpixel may be electrically connected to the first data line among the plurality of data lines.

In the driving method, each of the first sensing driving step and the second sensing driving step includes an initializing step, a tracking step that is performed during a predetermined boosting time after the initializing step, and a sampling step that is performed when a boosting time has elapsed since the initializing step. It can contain.

During the initializing step of the first sensing driving step, the first reference voltage may be supplied to the first reference voltage line, and the first sensing driving data voltage may be supplied to the first data line.

During the initialization step of the second sensing driving step, a second reference voltage different from the first reference voltage is supplied to the first reference voltage line, and the second sensing driving data is the same as the data voltage for the first sensing driving with the first data line. Voltage can be supplied.

During the tracking step of the first sensing driving step, the first reference voltage line increases in voltage from the first reference voltage, and during the tracking step of the second sensing driving step, the first reference voltage line increases in voltage from the second reference voltage This can proceed.

During the sampling step of the first sensing driving step, the analog-to-digital converter may output the first sensing value by sensing the voltage of the first reference voltage line. During the sampling step of the second sensing driving step, the analog-to-digital converter may output the second sensing value by sensing the voltage of the first reference voltage line.

In the driving method, after the first sensing driving step and the second sensing driving step, the gain and offset of the data voltage for driving the image to be supplied to the first subpixel are changed based on the first sensing value and the second sensing value. A compensation processing step of supplying the data line may be further included.

The gain and offset of the data voltage for driving the image may be changed according to a change in the mobility and threshold voltage of the driving transistor included in the first subpixel.

The first sensing driving step may be performed in the first blank period, and the second sensing driving step may be performed in a second blank period different from the first blank period.

In another aspect, embodiments of the present invention, a plurality of data lines and a plurality of gate lines are arranged, a plurality of reference voltage lines are arranged, a plurality of sub-pixels are arranged on the display panel; A data driving circuit driving a plurality of data lines; And a gate driving circuit for driving the plurality of gate lines, the plurality of sub-pixels being one of an organic light-emitting diode, a driving transistor for driving the organic light-emitting diode, a first node of the driving transistor, and a plurality of data lines A first transistor electrically connected between data lines, a second transistor electrically connected between a second node of the driving transistor and a corresponding reference voltage line among a plurality of reference voltage lines, and between a first node and a second node of the driving transistor It can provide a driving circuit of the organic light emitting display device including a capacitor electrically connected to.

The driving circuit includes: a data driving circuit for supplying a data voltage for sensing driving to a first data line electrically connected to a drain node or a source node of a first transistor included in any first subpixel among a plurality of subpixels; A reference voltage supply circuit that supplies a reference voltage to a first reference voltage line electrically connected to a drain node or a source node of the second transistor included in one subpixel may be included.

The reference voltage supply circuit may supply the first reference voltage to the first reference voltage line during the initialization period during the first sensing driving period.

The reference voltage supply circuit may supply a second reference voltage different from the first reference voltage to the first reference voltage line during the initialization period during the second sensing driving period different from the first sensing driving period.

The data driving circuit may supply the first sensing driving data voltage to the first data line during the initialization period during the first sensing driving period.

The data driving circuit may supply the second sensing driving data voltage equal to the first sensing driving data voltage to the first data line during the initialization period during the second sensing driving period.

According to embodiments of the present invention, there is an effect of providing a driving circuit, an organic light emitting display device and a driving method that enable accurate sensing and compensation while reducing the time required for sensing.

In addition, according to embodiments of the present invention, there is an effect of providing a driving circuit, an organic light emitting display device and a driving method capable of sensing a threshold voltage of a transistor in real time during image driving.

In addition, according to embodiments of the present invention, there is an effect of providing a driving circuit, an organic light emitting display device and a driving method capable of simultaneously sensing the threshold voltage and mobility of a transistor while driving an image.

1 is a schematic system configuration diagram of an organic light emitting display device according to embodiments of the present invention.
2 is an exemplary diagram of a system implementation of an organic light emitting display device according to embodiments of the present invention.
3 is a circuit of a subpixel of an organic light emitting display device according to embodiments of the present invention.
4 is a compensation circuit of an organic light emitting display device according to embodiments of the present invention.
5 is a driving timing diagram for threshold voltage sensing of an organic light emitting display device according to embodiments of the present invention.
6 is a driving timing diagram for sensing mobility of an organic light emitting display device according to embodiments of the present invention.
7 is a diagram illustrating a sensing process that can be performed at various timings in an organic light emitting display device according to embodiments of the present invention.
8 is a layout view of four sub-pixels and peripheral wires that can be connected to one sensing line in the organic light emitting display device according to embodiments of the present invention.
9 is an equivalent circuit of four sub-pixels connectable to one sensing line in the organic light emitting display device according to embodiments of the present invention.
10 is a conceptual diagram illustrating advanced real-time sensing of an organic light emitting display device according to embodiments of the present invention.
11 and 12 are driving timing diagrams for advanced real-time sensing of an organic light emitting display device according to embodiments of the present invention.
13 is a flowchart of a driving method for advanced real-time sensing of an organic light emitting display device according to embodiments of the present invention.
14 is a view showing a driving circuit for advanced real-time sensing of an organic light emitting display device according to embodiments of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. In adding reference numerals to the components of each drawing, the same components may have the same reference numerals as possible even though they are displayed on different drawings. In addition, in describing the present invention, when it is determined that detailed descriptions of related well-known configurations or functions may obscure the subject matter of the present invention, detailed descriptions thereof may be omitted.

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

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

Referring to FIG. 1, in the OLED display device 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 data lines DL and a plurality of A plurality of subpixels SP defined by the gate line GL may include a display panel 110 arranged in a matrix type and a driving circuit 111 for driving the display panel 110.

The driving circuit 111 is, functionally, a data driving circuit 120 driving a plurality of data lines DL, a gate driving circuit 130 driving a plurality of gate lines GL, and a data driving society A controller 140 for controlling the furnace 120 and the gate driving circuit 130 may be included.

In the display panel 110, a plurality of data lines DL and a plurality of gate lines GL may be disposed to cross each other. For example, the plurality of gate lines GL may be arranged in a row or a column, and the plurality of data lines DL may be arranged in a column or a row. Hereinafter, for convenience of description, it is assumed that the plurality of gate lines GL are arranged in a row, and the plurality of data lines DL are arranged in a column.

In addition to the plurality of data lines DL and the plurality of gate lines GL, other types of wirings may be disposed on the display panel 110.

The controller 140 may supply image data DATA to the data driving circuit 120.

In addition, the controller 140 supplies various control signals (DCS, GCS) required for driving operations of the data driving circuit 120 and the gate driving circuit 130, and thus the data driving circuit 120 and the gate driving circuit 130 You can control the operation.

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 driving circuit 120 to convert the converted image data (DATA). Output, and control the data driving at a suitable time according to the scan.

In order to control the data driving circuit 120 and the gate driving circuit 130, the controller 140 includes a vertical synchronization signal (Vsync), a horizontal synchronization signal (Hsync), and an input data enable (DE: Data Enable) signal, A timing signal such as a clock signal CLK is received from an external (eg, host system), and various control signals are generated and output to the data driving circuit 120 and the gate driving circuit 130.

For example, the controller 140 may control the gate driving circuit 130, a gate start pulse (GSP), a gate shift clock (GSC), and a gate output enable signal (GOE). : Gate Output Enable (GCS) outputs various gate control signals (GCS).

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

The controller 140 may be a timing controller used in a conventional display technology or a control device capable of further performing other control functions, including a timing controller.

The controller 140 may be implemented as a separate component from the data driving circuit 120 or integrated with the data driving circuit 120 to be implemented as an integrated circuit.

The data driving circuit 120 receives the image data DATA from the controller 140 and supplies data voltages to the plurality of data lines DL, thereby driving the plurality of data lines DL. Here, the data driving circuit 120 is also referred to as a source driving circuit.

The data driving circuit 120 may include a shift register, a latch circuit, a digital to analog converter (DAC), an output buffer, and the like.

The data driving circuit 120 may further include one or more analog to digital converters (ADCs).

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

The gate driving circuit 130 may include a shift register, a level shifter, and the like.

The gate driving circuit 130 sequentially supplies a scan signal of an on voltage or an off voltage to a plurality of gate lines GL under the control of the controller 140.

When a specific gate line is opened by the gate driving circuit 130, the data driving circuit 120 converts the image data DATA received from the controller 140 into an analog-type data voltage to convert a plurality of data lines DL. To supply.

The data driving circuit 120 may be located only on one side (for example, an upper side or a lower side) of the display panel 110, and in some cases, both sides of the display panel 110 may be driven according to a driving method, a panel design method, or the like. Example: It can be located on both the upper side and the lower side).

The gate driving circuit 130 may be located only on one side (eg, left or right) of the display panel 110, and in some cases, both sides of the display panel 110 may be driven according to a driving method, a panel design method, or the like. Example: both left and right sides).

The data driving circuit 120 may be implemented by including at least one source driver integrated circuit (SDIC).

Each source driver integrated circuit (SDIC) is connected to a bonding pad of the display panel 110 by a Tape Automated Bonding (TAB) method or a Chip On Glass (COG) method or directly disposed on the display panel 110 It may be. In some cases, each source driver integrated circuit (SDIC) may be integrated and disposed on the display panel 110. Further, each source driver integrated circuit (SDIC) may be implemented in a COF (Chip On Film) method. In this case, each source driver integrated circuit (SDIC) is mounted on the circuit film, it can be electrically connected to the data lines (DL) in the display panel 110 through the circuit film.

In the gate driving circuit 130, one or more gate driver ICs (GDICs) may be connected to a bonding pad of the display panel 110 in a TAB method or a COG method. In addition, the gate driving circuit 130 may be implemented in a GIP (Gate In Panel) type and may be directly disposed on the display panel 110. Also, the gate driving circuit 130 may be implemented in a COF (Chip On Film) method. In this case, each gate driver integrated circuit (GDIC) included in the gate driving circuit 130 is mounted on the circuit film and can be electrically connected to the gate lines GL in the display panel 110 through the circuit film. have..

2 is an exemplary diagram of a system implementation of an organic light emitting display device 100 according to embodiments of the present invention.

In the example of FIG. 2, each source driver integrated circuit (SDIC) included in the data driving circuit 120 is implemented by a chip on film (COF) method among various methods (TAB, COG, COF, etc.), and a gate driving circuit This is the case where 130 is implemented as a GIP (Gate In Panel) type among various methods (TAB, COG, COF, GIP, etc.).

Each of the plurality of source driver integrated circuits (SDIC) included in the data driving circuit 120 may be mounted on the source side circuit film SF.

One side of the source side circuit film SF may be electrically connected to the display panel 110.

On the source side circuit film SF, wirings for electrically connecting the source driver integrated circuit SDIC and the display panel 110 may be disposed.

The organic light emitting display device 100 mounts at least one source printed circuit board (SPCB), control components, and various electrical devices for circuit connection between a plurality of source driver integrated circuits (SDIC) and other devices. It may include a control printed circuit board (CPCB) for.

The other side of the source side circuit film SF on which the source driver integrated circuit SDIC is mounted may be connected to at least one source printed circuit board SPCB.

That is, one side of the source side circuit film SF on which the source driver integrated circuit SDIC is mounted may be electrically connected to the display panel 110 and the other side to be electrically connected to the source printed circuit board SPCB. .

The control printed circuit board (CPCB) includes a controller 140 that controls operations such as the data driving circuit 120 and the gate driving circuit 130, the display panel 110, the data driving circuit 120, and the gate driving circuit. A power management integrated circuit (PMIC) 210 for supplying various voltages or currents to the 130 or controlling various voltages or currents to be supplied may be mounted.

The at least one source printed circuit board (SPCB) and the control printed circuit board (CPCB) may be circuitly connected through at least one connecting member. Here, the connection member may be, for example, a flexible printed circuit (FPC), a flexible flat cable (FFC), or the like.

The at least one source printed circuit board (SPCB) and the control printed circuit board (CPCB) may be embodied as one printed circuit board.

The organic light emitting display device 100 may further include a set board (230) electrically connected to a control printed circuit board (CPCB). The set board 230 may also be referred to as a power board.

Main power management circuits 220 and M-PMCs (main power management circuits) for managing the overall power of the organic light emitting display device 100 may be present on the set board 230.

The power management integrated circuit 210 is a circuit that manages power for a display module including the display panel 110 and its driving circuits 120, 130, and 140, and the main power management circuit 220 is a display module. It is a circuit that manages the overall power including, and can interwork with the power management integrated circuit 210.

Each sub-pixel SP arranged in the display panel 110 included in the organic light emitting display device 100 according to the present exemplary embodiment includes an organic light emitting diode (OLED), which is a self-light emitting element, and organic light emitting. It may be composed of a circuit element such as a driving transistor (Driving Transistor) for driving the diode (OLED).

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

3 is a circuit of each sub-pixel SP of the organic light emitting display device 100 according to embodiments of the present invention.

The display panel 110 according to embodiments of the present invention includes a plurality of data lines DL, a plurality of gate lines GL, a plurality of driving voltage lines DVL, and a plurality of reference voltage lines RVL. Can be deployed.

Each sub-pixel SP in the display panel 110 includes an organic light emitting diode (OLED), a driving transistor (DRT) driving the organic light emitting diode (OLED), and a first node (N1) of the driving transistor (DRT) ) And the first transistor T1 electrically connected between the corresponding data line DL, the second node N2 of the driving transistor DRT, and the corresponding reference voltage line RVL among the plurality of reference voltage lines RVL. It may be implemented by including a second transistor T2 electrically connected therebetween, a storage capacitor Cst electrically connected between the first node N1 and the second node N2 of the driving transistor DRT, and the like. .

The organic light emitting diode (OLED) may be formed of an anode electrode, an organic light emitting layer and a cathode electrode.

According to the circuit example of FIG. 3, the anode electrode of the organic light emitting diode OLED may be electrically connected to the second node N2 of the driving transistor DRT. A ground voltage (EVSS) may be applied to the cathode electrode of the organic light emitting diode (OLED).

Here, the ground voltage EVSS may be, for example, a ground voltage or a voltage higher or lower than the ground voltage. In addition, the electromotive voltage EVSS may vary depending on the driving state. For example, the base voltage (EVSS) when driving an image and the base voltage (EVSS) when sensing is driven may be set differently.

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

The driving transistor DRT may include a first node N1, a second node N2, a third node N3, and the like.

The first node N1 of the driving transistor DRT may be a gate node, and may be electrically connected to a source node or a drain node of the first transistor T1. The second node N2 of the driving transistor DRT may be a source node or a drain node, and may be electrically connected to the anode electrode (or cathode electrode) of the organic light emitting diode (OLED), and the second transistor T2 The source node or the drain node can also be electrically connected. The third node N3 of the driving transistor DRT may be a drain node or a source node, a driving voltage EVDD may be applied, and a driving voltage line DVL that supplies the driving voltage EVDD ). In the following description, for convenience of explanation, for example, in the driving transistor DRT, the first node N1 is a gate node, the second node N2 is a source node, and the third node N3 is a drain node. You can listen and explain.

The storage capacitor Cst is electrically connected between the first node N1 and the second node N2 of the driving transistor DRT to perform a data voltage Vdata corresponding to the image signal voltage or a voltage corresponding thereto. It can be maintained for a frame time (or a fixed time).

The drain node or source node of the first transistor T1 is electrically connected to the corresponding data line DL, and the source node or drain node of the first transistor T1 is the first node N1 of the driving transistor DRT And the gate node of the first transistor T1 is electrically connected to the corresponding gate line to receive the scan signal SCAN.

The first transistor T1 may receive the scan signal SCAN through the corresponding gate line to the gate node and control on-off.

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

The drain node or source node of the second transistor T2 is electrically connected to the reference voltage line RVL, and the source node or drain node of the second transistor T2 is the second node N2 of the driving transistor DRT It can be electrically connected to. The gate node of the second transistor T2 is electrically connected to the corresponding gate line to receive a sense signal SENSE.

The second transistor T2 receives the sense signal SENSE to the gate node through the corresponding gate line, and on-off may be controlled.

The second transistor T2 is turned on by the sense signal SENSE to transfer the reference voltage Vref supplied from the reference voltage line RVL to the second node N2 of the driving transistor DRT. have.

Meanwhile, the storage capacitor Cst is not a parasitic capacitor (eg, Cgs, Cgd) which is an internal capacitor existing between the first node N1 and the second node N2 of the driving transistor DRT. , May be an external capacitor intentionally designed outside the driving transistor DRT.

Each of the driving transistor DRT, the first transistor T1, and the second transistor T2 may be an n-type transistor or a p-type transistor.

Meanwhile, the scan signal SCAN and the sense signal SENSE may be separate gate signals. In this case, the scan signal SCAN and the sense signal SENSE may be respectively applied to the gate node of the first transistor T1 and the gate node of the second transistor T2 through different gate lines.

In some cases, the scan signal SCAN and the sense signal SENSE may be the same gate signal. In this case, the scan signal SCAN and the sense signal SENSE may be commonly applied to the gate node of the first transistor T1 and the gate node of the second transistor T2 through the same gate line.

Each sub-pixel structure illustrated in FIG. 3 is a 3T (Transistor) 1C (Capacitor) structure, and is only an example for description, and further includes one or more transistors, or, in some cases, one or more capacitors. It might be. Alternatively, each of the plurality of sub-pixels may have the same structure, and some of the plurality of sub-pixels may have a different structure.

Hereinafter, an image driving operation of each sub-pixel SP will be briefly described as an example.

The display driving operation (also referred to as image driving) of each subpixel SP may be performed in an image data recording step, a boosting step, and a light emitting step.

In the image data recording step, the image driving data voltage Vdata corresponding to the image signal is applied to the first node N1 of the driving transistor DRT, and the image is applied to the second node N2 of the driving transistor DRT. The driving reference voltage Vref may be applied. Here, due to the resistance component between the second node N2 of the driving transistor DRT and the reference voltage line RVL, a voltage similar to the reference voltage Vref to the second node N2 of the driving transistor DRT (Vref ') can be applied.

The reference voltage Vref for driving the image is also referred to as VpreR.

In the image data recording step, the first transistor T1 and the second transistor T2 may be turned on at the same time or with a slight time difference.

In the image data recording step, the storage capacitor Cst may be charged with a charge corresponding to the potential difference between both ends (Vdata-Vref or Vdata-Vref ').

The application of the data voltage Vdata for driving the image to the first node N1 of the driving transistor DRT is referred to as image data writing.

In the boosting step subsequent to the image data recording step, the first node N1 and the second node N2 of the driving transistor DRT may be floated simultaneously or electrically with a slight time difference.

To this end, the first transistor T1 may be turned off by the turn-off level voltage of the scan signal SCAN. Also, the second transistor T2 may be turned off by the turn-off level voltage of the sense signal SENSE.

In the boosting step, while the voltage difference between the first node N1 and the second node N2 of the driving transistor DRT is maintained, each of the first node N1 and the second node N2 of the driving transistor DRT is maintained. The voltage of can be boosted.

During the boosting step, the voltage of each of the first node N1 and the second node N2 of the driving transistor DRT is boosted, and then the increased voltage of the second node N2 of the driving transistor DRT is When a certain voltage (ie, a voltage capable of turning on the organic light emitting diode (OLED), a voltage higher than the threshold voltage of the organic light emitting diode (OLESS) from the base voltage (EVSS)), the light emitting step is entered.

In this light emitting step, a driving current flows to the organic light emitting diode (OLED). Accordingly, the organic light emitting diode (OLED) can emit light.

The driving transistor DRT disposed in each of the plurality of subpixels SP arranged on the display panel 110 according to embodiments of the present invention has unique characteristic values such as threshold voltage and mobility (also referred to as electron mobility). Have

Deterioration of the driving transistor DRT may occur depending on a driving time. Accordingly, the unique characteristic value of the driving transistor DRT may change according to the driving time.

The driving transistor DRT may have an on-off timing or a driving capability of the organic light emitting diode OLED according to a change in a characteristic value. That is, the timing of supplying the current to the organic light emitting diode (OLED) and the amount of current supplied to the organic light emitting diode (OLED) may be changed in the driving transistor DRT according to a change in the characteristic value. According to the change in the characteristic value of the driving transistor DRT, the actual luminance of the corresponding subpixel SP may be different from the desired luminance.

In addition, the driving times of the plurality of subpixels SP arranged on the display panel 110 may be different from each other. Accordingly, a characteristic value deviation (threshold voltage deviation, mobility deviation) between the driving transistors DRT in each subpixel SP may occur.

The variation in the characteristic values between the driving transistors DRT may generate a variation in luminance between the sub-pixels SP. Accordingly, the luminance uniformity of the display panel 110 may also be deteriorated, which in turn may lead to image quality deterioration.

Accordingly, the organic light emitting display device 100 according to the exemplary embodiments of the present invention includes a compensation circuit capable of compensating for variation in characteristic values between the driving transistors DRT, and provides a compensation method using the same. This will be described in more detail with reference to FIGS. 4 to 7.

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

The organic light emitting diode display 100 according to embodiments of the present invention needs to sense a characteristic value or a change in the characteristic value of each driving transistor DRT in order to compensate for variations in characteristic values between the driving transistors DRT.

The compensation circuit of the organic light emitting display device 100 according to the exemplary embodiments of the present invention drives a subpixel SP having a 3T1C structure or a modified structure based thereon (sensing driving) to drive within the subpixel SP A sensing circuit 410 for sensing a characteristic value or a change in characteristic value of the transistor DRT may be included.

In this specification, for convenience of description, "sensing a characteristic value or characteristic value change of the driving transistor DRT in the subpixel SP" is also referred to as "sensing the subpixel SP". In addition, "compensating for the characteristic value or characteristic value change of the driving transistor DRT in the subpixel SP" is also referred to as "compensating the subpixel SP".

The organic light emitting diode display 100 according to embodiments of the present invention senses the voltage of the reference voltage line RVL through sensing driving, and detects the voltage of the driving transistor DRT in the subpixel SP from the sensed voltage. The characteristic value or characteristic value change can be found. Here, the reference voltage line RVL not only serves to transmit the reference voltage Vref, but also serves to deliver the reference voltage Vref, and senses characteristics of a subpixel (eg, a characteristic value of the driving transistor DRT). It can serve as a sensing line.

More specifically, according to the sensing driving of the organic light emitting display device 100 according to embodiments of the present invention, the characteristic value or characteristic value change of the driving transistor DRT is the voltage of the second node N2 of the driving transistor DRT. (Example: Vdata-Vth).

The voltage of the second node N2 of the driving transistor DRT may correspond to the voltage of the reference voltage line RVL when the second transistor T2 is turned on. The line capacitor Cline on the reference voltage line RVL may be charged by the voltage of the second node N2 of the driving transistor DRT. The reference voltage line RVL may have a voltage corresponding to the voltage of the second node N2 of the driving transistor DRT by the charged line capacitor Cline.

The compensation circuit of the organic light emitting display device 100 according to the exemplary embodiments of the present invention includes on-off control of each of the first transistor T1 and the second transistor T2 in the sub-pixel SP to be sensed. , Through the supply control of each of the data voltage Vdata and the reference voltage Vref, the second node N2 of the driving transistor DRT changes the characteristic value (threshold voltage, mobility) or characteristic value of the driving transistor DRT. It can be driven to reflect the voltage state.

Referring to FIG. 4, the organic light emitting display device 100 according to embodiments of the present invention may include a sensing circuit 410 for sensing a plurality of reference voltage lines RVL.

The sensing circuit 410 senses the voltage of the reference voltage line RVL corresponding to the voltage of the second node N2 of the driving transistor DRT, and converts the sensed voltage into a sensing value corresponding to a digital value. An analog-to-digital converter (ADC) and a switch circuit (SAM, SPRE) for sensing driving may be included.

The sensing circuit 410 may exist outside the data driving circuit 120 (for example, a PCB), but may also be included in the data driving circuit 120.

The switching circuits for sensing driving (SAM, SPRE) may control the voltage state of the corresponding reference voltage line (RVL) or control whether the reference voltage line (RVL) is connected to the analog-to-digital converter (ADC).

The switch circuits for sensing driving (SAM, SPRE) include a reference switch for sensing driving that controls connection between each reference voltage line RVL and a reference voltage supply node Npres for sensing driving to which the reference voltage Vref is supplied ( SPRE) and a sampling switch (SAM) for controlling the connection between each reference voltage line (RVL) and an analog-to-digital converter (ADC).

The reference switch SPRE for sensing driving is the switch used for sensing driving. The reference voltage Vref supplied to the reference voltage line RVL by the reference switch SPRE for sensing driving is “reference voltage for sensing driving VpreS”.

Meanwhile, referring to FIG. 4, the switch circuit may include a reference switch (RPRE) for driving a video used when driving the video.

The reference switch RPRE for driving an image may control connection between each reference voltage line RVL and a reference voltage supply node Nprer for driving an image to which the reference voltage Vref is supplied.

The above-mentioned reference switch for driving an image (RPRE) is a switch used when driving an image. The reference voltage Vref supplied to the reference voltage line RVL by the reference switch SPRE for driving the image is “reference voltage VpreR for driving the image”.

The reference switch SPRE for driving and the reference switch RPRE for driving the image may be provided separately, or may be integrated and implemented as one. The sensing driving reference voltage VpreS and the image driving reference voltage VpreR may be the same voltage value or different voltage values.

The compensation circuit of the organic light emitting display device 100 according to embodiments of the present invention includes a memory MEM and a memory (MEM) storing a sensing value output from an analog-to-digital converter (ADC) or storing a reference sensing value in advance. MEM) may further include a compensator (COMP) that compares a sensing value stored in the MEM) with a reference sensing value to calculate a compensation value that compensates for a deviation in a characteristic value.

The compensation value calculated by the compensator COMP can be stored in the memory MEM.

The controller 140 changes the image data Data to be supplied to the data driving circuit 120 using the compensation value calculated by the compensator COM, and outputs the changed image data Data_comp to the data driving circuit 120 can do.

Accordingly, the data driving circuit 120 converts the image data (Data_comp) changed through the digital-to-analog converter (DAC) into a data voltage (Vdata_comp) in the form of an analog signal, and outputs the converted data voltage (Vdata_comp) to the output buffer ( BUF) to output to the corresponding data line (DL). Accordingly, the characteristic value deviation (threshold voltage deviation, mobility deviation) with respect to the driving transistor DRT of the corresponding subpixel SP may be compensated.

Meanwhile, referring to FIG. 4, the data driving circuit 120 may include a data voltage output circuit 400 including a latch circuit, a digital analog converter (DAC), an output buffer (BUF), and the like. Accordingly, an analog-to-digital converter (ADC) and various switches (SAM, SPRE, RPRE) may be further included.

Alternatively, the analog-to-digital converter (ADC) and various switches (SAM, SPRE, RPRE) may be located outside the data driving circuit 120, not inside the data driving circuit 120.

Referring to FIG. 4, the compensator COMP may exist outside the controller 140, but may also be included inside the controller 140. Also, the memory MEM may be located outside the controller 140 or may be implemented in the form of a register inside the controller 140.

5 is a driving timing diagram for threshold voltage sensing of the organic light emitting display device 100 according to embodiments of the present invention.

Referring to FIG. 5, the threshold voltage sensing driving may be performed in an initialization step (S510), a tracking step (S520), and a sampling step (S530).

In the initialization step S510, the first transistor T1 is turned on by the scan signal SCAN of the turn-on level voltage. Accordingly, the first node N1 of the driving transistor DRT is initialized to a threshold voltage sensing driving data voltage Vdata.

In the initialization step S510, the second transistor T2 is turned on by the sense signal SENSE of the turn-on level voltage, and the reference switch SPRE for sensing driving is turned on. Accordingly, the second node N2 of the driving transistor DRT is initialized to a reference voltage VpreS for sensing driving.

The tracking step S520 is a step of tracking the threshold voltage Vth of the driving transistor DRT. That is, in the tracking step S520, the voltage of the second node N2 of the driving transistor DRT reflecting the threshold voltage Vth of the driving transistor DRT is tracked.

In the tracking step S520, the first transistor T1 and the second transistor T2 maintain a turn-on state, and the reference switch SPRE for sensing driving is turned off. Accordingly, the second node N2 of the driving transistor DRT is floated, and the voltage of the second node N2 of the driving transistor DRT starts to rise from the reference voltage VpreS for sensing driving.

Since the second transistor T2 is turned on, the voltage increase of the second node N2 of the driving transistor DRT leads to a voltage increase of the reference voltage line RVL.

The voltage of the second node N2 of the driving transistor DRT rises and then becomes saturation. The saturated voltage of the second node N2 of the driving transistor DRT corresponds to the voltage difference Vdata-Vth of the threshold voltage Vth of the driving transistor DRT from the threshold voltage sensing driving data voltage Vdata. do.

Accordingly, when the voltage of the second node N2 of the driving transistor DRT is saturated, the voltage Vrvl of the reference voltage line RVL is from the threshold voltage sensing driving data voltage Vdata to the driving transistor DRT. Corresponds to the voltage difference (Vdata-Vth) of the threshold voltage.

When the voltage of the second node N2 of the driving transistor DRT becomes saturated, the sampling switch SAM is turned on, and the sampling step S530 proceeds.

In the sampling step S530, the analog-to-digital converter ADC senses the voltage Vrvl of the reference voltage line RVL connected by the sampling switch SAM as the sensing voltage Vsen, and senses the sensing voltage Vsen. It can be converted into a sensing value corresponding to a digital value. Here, the voltage Vsen sensed by the analog-to-digital converter ADC corresponds to "Vdata-Vth".

The compensator COMP can determine the threshold voltage of the driving transistor DRT of the corresponding subpixel SP based on the sensing value output from the analog-to-digital converter ADC and determine the determined threshold voltage of the driving transistor DRT. You can compensate.

The compensator COMP includes a sensing value (a digital value corresponding to Vdata-Vth) measured through sensing driving and a threshold voltage sensing driving data (a digital value corresponding to Vdata) already known from the driving transistor DRT. The threshold voltage Vth can be determined.

The compensator COMP compares the threshold voltage Vth determined for the corresponding driving transistor DRT with a reference threshold voltage or a threshold voltage of another driving transistor DRT to compensate for a deviation in the threshold voltage between the driving transistors DRT. I can do it. Here, the threshold voltage deviation compensation may mean image data change processing (process to add or subtract compensation values (offset) to image data).

6 is a driving timing diagram for sensing mobility of the organic light emitting display device 100 according to embodiments of the present invention.

Referring to FIG. 6, the mobility sensing driving may proceed to an initialization step (S610), a tracking step (S620), and a sampling step (S630).

In the initialization step S610, the first transistor T1 is turned on by the scan signal SCAN of the turn-on level voltage. Accordingly, the first node N1 of the driving transistor DRT is initialized with a data voltage Vdata for mobility sensing driving.

In the initialization step S610, the second transistor T2 is turned on by the sense signal SENSE of the turn-on level voltage, and the reference switch SPRE for sensing driving is turned on. Accordingly, the second node N2 of the driving transistor DRT is initialized to a reference voltage VpreS for sensing driving.

The tracking step S620 is a step of tracking the mobility of the driving transistor DRT. The mobility of the driving transistor DRT may indicate the current driving capability of the driving transistor DRT. That is, in the tracking step S520, the voltage of the second node N2 of the driving transistor DRT capable of calculating the mobility of the driving transistor DRT is tracked.

In the tracking step S620, the first transistor T1 is turned off by the scan signal SCAN of the turn-off level voltage, and the reference switch SPRE for sensing driving is turned off. Accordingly, both the first node N1 and the second node N2 of the driving transistor DRT are floated. Accordingly, the voltages of the first node N1 and the second node N2 of the driving transistor DRT are both increased. In particular, the voltage of the second node N2 of the driving transistor DRT starts to rise from the reference voltage VpreS for sensing driving.

Since the second transistor T2 is turned on, the voltage increase of the second node N2 of the driving transistor DRT leads to a voltage increase of the reference voltage line RVL.

When a predetermined time Δt has elapsed since the voltage of the second node N2 of the driving transistor DRT starts to rise, the sampling switch SAM is turned on, and the sampling step S630 proceeds. do.

In the sampling step S630, the analog-to-digital converter ADC senses the voltage Vrvl of the reference voltage line RVL connected by the sampling switch SAM as the sensing voltage Vsen, and senses the sensing voltage Vsen. It can be converted into a sensing value corresponding to a digital value. Here, the voltage Vsen sensed by the analog-to-digital converter ADC corresponds to a voltage VpreS + ΔV raised by a constant voltage ΔV from the sensing driving reference voltage VpreS. Here, the predetermined time Δt is a predetermined time, and may also be described as a boosting time below.

The compensator COMP can determine the mobility of the driving transistor DRT of the corresponding subpixel SP based on the sensed value output from the analog-to-digital converter ADC and determine the mobility of the driving transistor DRT. You can compensate.

The compensator COMP includes a sensing value (a digital value corresponding to VpreS + ΔV) measured through sensing driving, a reference voltage VpreS for sensing driving, and an elapsed time Δt of the driving transistor DRT. Mobility can be grasped.

The mobility of the driving transistor DRT is proportional to the voltage variation (ΔV / Δt) per unit time of the reference voltage line RVL in the tracking step S620. That is, the mobility of the driving transistor DRT is proportional to the slope SLP in the voltage waveform of the reference voltage line RVL in FIG. 6.

The compensator COMP may compare the mobility identified for the driving transistor DRT with reference mobility or mobility of another driving transistor DRT to compensate for the mobility deviation between the driving transistors DRT. Here, the mobility deviation compensation may mean image data change processing (operation processing to multiply image data by a compensation value (gain)).

7 is a diagram illustrating a sensing process that can be performed at various timings in the organic light emitting display device 100 according to embodiments of the present invention.

Referring to FIG. 7, when the power-on signal is generated, the organic light emitting display device 100 performs predetermined on-sequence processing for starting the display driving, and when the on-sequence processing is completed, normal display driving is started.

When the power-off signal is generated, the organic light emitting display device 100 stops driving the display in progress and performs a predetermined off-sequence process. When the off-sequence process is completed, the organic light emitting display device 100 is completely off.

Sensing driving (threshold voltage sensing driving, mobility sensing driving) may be performed in connection with the power processing timing.

The sensing driving may be performed before the display driving starts after the power-on signal is generated. Such sensing and sensing processes are referred to as on-sensing and on-sensing processes.

Further, sensing driving may be performed after the generation of a power-off signal. These sensing and sensing processes are referred to as off-sensing and off-sensing processes.

In addition, sensing driving may be performed in real time among display driving. This sensing processor is called a real-time (RT: Real-Time, hereinafter, RT) sensing process.

In the case of the RT sensing process, sensing driving may be performed on one or more sub-pixels SP in one or more sub-pixel lines (sub-pixel rows) every blank time among display driving.

When sensing driving (RT sensing driving) is performed at a blank time, a sub-pixel line (sub-pixel row) on which sensing driving is performed may be randomly selected. Accordingly, an image anomaly in the subpixel line that has been sensed in the active time after sensing in the blank time can be alleviated. In addition, a recovery data voltage corresponding to the data voltage prior to the sensing driving may be supplied to the subpixels that are sensing driven at the active time after sensing driving at the blank time. Accordingly, an image anomaly in the subpixel line that has been sensed in the active time after sensing in the blank time can be alleviated.

Meanwhile, since the mobility sensing driving requires only a relatively short time compared to the threshold voltage sensing driving, it can be performed by any of the on-sensing process and the RT sensing process that are performed for a short time.

For example, the mobility sensing driving may be performed as an on-sensing process to obtain a reference sensing value after a power-on signal is generated, and may also be performed as an RT sensing process using blank periods during image driving.

However, in the case of threshold voltage sensing driving, since the voltage of the second node N2 of the driving transistor DRT may take a long time to saturate, it may proceed to an off-sensing process that may be performed for a rather long time. You can.

In particular, when the number of sub-pixels increases according to a high resolution, it may take a very long time to sense the threshold voltage of the driving transistor DRT in all sub-pixels SP disposed on the display panel 110. The voltage sensing driving may be performed as an RT sensing process during image driving.

In addition, after performing the threshold voltage sensing driving, when performing the mobility sensing driving, the sensing driving data voltage Vdata_sen for the mobility sensing driving may be a data voltage to which a threshold voltage compensation value is applied. That is, the sensing driving data voltage Vdata_sen for mobility sensing driving may be a data voltage offset by a voltage corresponding to a threshold voltage compensation value.

Meanwhile, the reference value of the threshold voltage sensing value and the reference value of the mobility sensing value are obtained in advance before shipment of the product and stored in the memory MEM.

Meanwhile, one data voltage Vdata, two gate signals SCAN, SENSE, a reference voltage Vref, and a driving voltage EVDD are included in one subpixel SP having the structure as shown in FIG. 3. Should be supplied. Therefore, one sub-pixel SP is electrically connected to one data line DL, one or two gate lines GL, one reference voltage SL, and one driving voltage line DVL. (See FIG. 3).

In order to turn on / off one subpixel row, one or two gate lines GL should be arranged for each subpixel row. However, below, for convenience of description, it is assumed that two gate lines GL are arranged in one sub-pixel row. According to this assumption, the scan signal SCAN and the sense signal SENSE may be transmitted through the two gate lines GL, respectively.

In addition, since the data voltage Vdata must be supplied for each subpixel SP, one data line DL may be disposed for each subpixel column. In some cases, one data line DL may be commonly arranged for every two subpixel columns.

Since the driving voltage EVDD may be a common voltage, one driving voltage line DVL may be disposed for each sub-pixel column (or one sub-pixel row), or two or more sub-pixel columns (or 2) One driving voltage line DVL may be disposed for each of the subpixel columns).

Similarly, since the reference voltage Vref may be a common voltage, one reference voltage line RVL may be disposed for each subpixel column (or one subpixel row), or two or more subpixel columns ( Alternatively, one reference voltage line RVL may be disposed for each of two or more subpixel columns.

When one driving voltage line DVL and / or one reference voltage line RVL is disposed in every two or more subpixel columns (or two or more subpixel columns), the aperture ratio of the display panel 110 is further increased. Can give.

For example, when the display panel 100 is composed of sub-pixels emitting four colors (red, green, blue, and white), one reference voltage line RVL is disposed for every four sub-pixel columns. You can. In this case, all the subpixels included in the four subpixel columns may be supplied with a reference voltage Vref from one reference voltage line RVL or sensed through one reference voltage line RVL.

Below, in order to increase the aperture ratio of the display panel 110, one driving voltage line DVL is disposed parallel to the data line DL for every four or more subpixel columns, and one for every four or more subpixel columns. The structure in which the two reference voltage lines RVL are arranged in parallel with the data lines DL will be described with reference to FIG. 8.

8 is in the organic light emitting display device 100 according to embodiments of the present invention, one sub-pixel (SP1 ~ SP4) that can be connected to one first reference voltage line (RVL1) and its peripheral wiring (DL1 ~ It is a layout diagram of DL4, DVL1, DVL2, SL1, GL1, GL2, and FIG. 9 is an equivalent circuit in which the subpixel structure of FIG. 3 and the sensing circuit 410 are applied to the arrangement of FIG. 8.

One sub-pixel row may include many sub-pixels, of which four sub-pixels SP1 to SP4 are electrically connected to the first reference voltage line RVL1, as illustrated in FIGS. 8 and 9. This is possible.

Each of the four subpixels SP1 to SP4 may refer to a subpixel representing four subpixel columns. That is, the first subpixel SP1 represents the first subpixel column, the second subpixel SP2 represents the second subpixel column, and the third subpixel SP3 represents the third subpixel column. As a representative, the fourth subpixel SP4 may represent a fourth subpixel column. Therefore, the arrangement structure of FIGS. 8 and 9 may be enlarged and applied to the display panel 110.

According to the example of FIG. 8, the scan signal SCAN applied to the gate node of the first transistor T1 included in each of the four subpixels SP1 to SP4 and the gate node of the second transistor T2 are applied. It is assumed that the sense signals SENSE are separate gate signals from each other.

Accordingly, the gate line GL1 for transmitting the scan signal SCAN to each of the four subpixels SP1 to SP4 included in one subpixel row and the sense signal to each of the four subpixels SP1 to SP4. A gate line GL2 for transmitting (SENSE) may be disposed.

Four data lines DL1 to DL4 for supplying the data voltage Vdata to each of the four subpixels SP1 to SP4 may be disposed on the display panel 110.

The first data line DL1 and the second data line DL2 may be positioned between the first subpixel SP1 and the second subpixel SP2. The third data line DL3 and the fourth data line DL4 may be positioned between the third subpixel SP3 and the fourth subpixel SP4.

In order to increase the aperture ratio of the display panel 110, the driving voltage lines DVL1 and DVL2 transferring the driving voltage EVDD, which may be a common voltage, and the first transmitting the reference voltage Vref which may be a common voltage. The reference voltage line RVL1 may be arranged in a shared structure.

That is, the driving voltage lines DVL1 and DVL2 may not be disposed one for each subpixel column, but may be disposed one for a plurality of subpixel columns. The first reference voltage line RVL1 may not be disposed one for each subpixel column, but may be disposed one for each subpixel column.

More specifically, the first sub-pixel SP1 and the second sub-pixel SP2 may be commonly supplied with the driving voltage EVDD through the first driving voltage line DVL1. The third sub-pixel SP3 and the fourth sub-pixel SP4 may be commonly supplied with the driving voltage EVDD through the second driving voltage line DVL2.

The source node or the drain node of the second transistor T1 included in each of the first subpixel SP1, the second subpixel SP2, the third subpixel SP3, and the fourth subpixel SP4 is the first It may be commonly connected to the reference voltage line RVL1.

Accordingly, the first to fourth subpixels SP1 to SP4 may be commonly supplied with the reference voltage Vref through one first reference voltage line RVL1.

Meanwhile, referring to FIGS. 8 and 9, as an example, one first reference voltage line RVL1 may be disposed between the second sub-pixel SP2 and the third sub-pixel SP3. In this case, the first subpixel SP1 and the fourth subpixel SP4 may be connected to one first reference voltage line RVL1 through a connection line CL. The connection line CL may be integral with the first reference voltage line RVL1 or may be located on a different layer from the first reference voltage line RVL1 to be contacted.

Meanwhile, the data lines DL1 to DL4 may be symmetrically arranged based on one first reference voltage line RVL1. The driving voltage lines DVL1 and DVL2 may be symmetrically arranged based on one first reference voltage line RVL1.

8 and 9, the sensing circuit 410 may be connected to one first reference voltage line RVL1. Accordingly, at one time point, only one subpixel among the four subpixels SP1 to SP4 may be sensed.

8 and 9, sensing and compensation will be described when one first reference voltage line RVL1 is shared by four sub-pixels SP1 to SP4. However, in the following description, the mobility sensing proceeding at the timing shown in FIG. 6 will be described as an example.

As described above, in the case of threshold voltage sensing driving, since the voltage of the second node N2 of the driving transistor DRT may take a long time to saturate, it may take a long time to perform off-sensing. It can proceed as a process. In particular, when the number of sub-pixels increases according to a high resolution, it may take a very long time to sense the threshold voltage of the driving transistor DRT in all sub-pixels SP disposed on the display panel 110. The voltage sensing driving may be performed as an RT sensing process during image driving.

Therefore, the threshold voltage sensing driving process of obtaining the reference value of the threshold voltage sensing value before shipping the product has a disadvantage that it takes too long. In addition, after the product is shipped, if the threshold voltage sensing driving is performed only as an off-sensing process, there is a disadvantage in that image quality deteriorates because the threshold voltage change during image driving is not immediately reflected. In particular, there is a possibility that a threshold voltage change may greatly occur during long-time image driving. In this case, the instantaneous threshold voltage change cannot be compensated by the threshold voltage sensing driving performed by the off sensing process.

In addition, when the threshold voltage sensing driving is in progress by the off-sensing process, when the user turns off the power itself or turns on the power again, the threshold voltage sensing driving is not normally completed, and thus the threshold voltage change cannot be compensated.

Accordingly, embodiments of the present invention can provide a driving method capable of sensing a threshold voltage while driving an image. In addition, embodiments of the present invention may provide a driving method capable of sensing both mobility and threshold voltage during image driving. Hereinafter, the driving method will be described in detail.

10 is a conceptual diagram for explaining advanced real-time sensing (ARTS) of the organic light emitting display device 100 according to embodiments of the present invention.

In the following, an arbitrary first subpixel SP1 among the plurality of subpixels SP is taken as an example. The first sub-pixel SP1 is electrically connected to the first reference voltage line RVL1 and the first data line DL1.

Referring to FIG. 10, according to advanced real-time sensing (ARTS), the sensing driving scheme for the first subpixel SP1 in each of two or more different sensing driving periods SDP1 and SDP2 is sensing driving in FIG. 6. It is basically the same as the method.

However, according to advanced real-time sensing (ARTS), the sensing driving reference voltages VpreS1 and VpreS2 used in each of two or more different sensing driving periods SDP1 and SDP2 may be varied. That is, the first sensing driving reference voltage VpreS1 used in the first sensing driving period SDP1 and the second sensing driving reference voltage VpreS2 used in the second sensing driving period SDP2 may be different. .

Further, according to the advanced real-time sensing (ARTS), based on the sensing voltages (Vsen1, Vsen2) obtained in each of two or more different sensing driving periods (SDP1, SDP2), each of two or more different sensing driving periods (SDP1, SDP2), respectively The mobility corresponding to is not sensed immediately.

In other words, the mobility of the driving transistor DRT in the first subpixel SP1 is not immediately sensed based on the first sensing voltage Vsen1 obtained in the first sensing driving period SDP1. In addition, the mobility of the driving transistor DRT in the first sub-pixel SP1 is not immediately sensed based on the second sensing voltage Vsen2 obtained in the second sensing driving period SDP2.

Instead, according to the advanced real-time sensing (ARTS), after two or more different sensing driving periods (SDP1, SDP2) are all progressed, the sensing voltages (Vsen1, Vsen2) obtained in each of the two or more sensing driving periods (SDP1, SDP2) Based on the calculation process, the threshold voltage and mobility of the driving transistor DRT in the first subpixel SP1 are simultaneously sensed.

Here, sensing the mobility may include sensing the change in mobility. Sensing the threshold voltage may include sensing a threshold voltage change. In addition, sensing the threshold voltage and the mobility at the same time may mean calculating the threshold voltage or a change thereof and the mobility or the change at the same time through arithmetic processing.

The calculation processing for simultaneously sensing the threshold voltage and mobility is used in each of two or more sensing voltages Vsen1 and Vsen2 obtained in each of the two or more sensing driving periods SDP1 and SDP2, and in two or more sensing driving periods SDP1 and SDP2, respectively. Data voltages for sensing driving (Vdata_sen1, Vdata_sen2) used in each of two or more sensing driving reference voltages (VpreS1, VpreS2), two or more sensing driving periods (SDP1, SDP2), and two or more sensing driving periods (SDP1, SDP2) This is a process of calculating a threshold voltage and mobility by using a predetermined boosting time (Δt) used and a known capacitance C of the line capacitor Cline on the first reference voltage line RVL1.

Here, the two or more sensing voltages Vsen1 and Vsen2 obtained in each of the two or more sensing driving periods SDP1 and SDP2 may be the same or different from each other. Two or more sensing driving reference voltages VpreS1 and VpreS2 used in each of the two or more sensing driving periods SDP1 and SDP2 may be different from each other. The sensing driving data voltages Vdata_sen1 and Vdata_sen2 used in each of the two or more sensing driving periods SDP1 and SDP2 may be the same. The predetermined boosting times Δt used in the two or more sensing driving periods SDP1 and SDP2 may be the same.

When performing such a calculation process, the compensator (COMP), for each of the two or more sensing driving periods (SDP1, SDP2), already knows the values (Vdata_sen, VpreS, C, Δt) and the measured values (Vsen) below Substituting in (1) and (2) to obtain equation (3) generated from equations (1) and (2). In equation (3), there are two unknowns (α, Vth).

The compensator COMP calculates threshold voltages Vth and α by obtaining solutions of the equations (α, Vth) of two or more equations (3) obtained for each of the two or more sensing driving periods SDP1 and SDP2. It is possible to calculate the mobility (μ) from α.

In Equations (1) to (3), Id is a current flowing from the drain node N3 of the driving transistor DRT to the source node N2. Vgs is a voltage difference between the first node N1 and the second node N2 of the driving transistor DRT. Vth is the threshold voltage of the driving transistor DRT. Vdata_sen is a sensing driving data voltage, and is set to a constant value without being changed according to the sensing driving periods SDP1 and SDP2. VpreS is a reference voltage for sensing driving and is a variable value depending on sensing driving periods SDP1 and SDP2. C is a capacitance of the line capacitor Cline of the reference voltage line RVL, and is a value determined according to the panel design. dv / dt is a differential value of the voltage of the corresponding reference voltage line RVL with respect to time during sensing driving. dv / dt may correspond to the voltage change amount ΔV of the corresponding reference voltage line RVL during the boosting time Δt. That is, dv / dt may correspond to ΔV / Δt. The voltage change amount ΔV of the corresponding reference voltage line RVL may correspond to a difference value Vsen-VpreS between the sensing voltage Vsen and the reference voltage VpreS for sensing driving.

In the formulas (1) and (3), α is an item corresponding to (1/2) μ × Cox × W / L. Here, μ is the mobility of the driving transistor (DRT), Cox is the capacitance per unit area of the parallel plate capacitor formed by the gate electrode and the channel, W is the channel width of the driving transistor (DRT), L is the driving transistor ( DRT) channel length. Since Cox and W / L are fixed values, α may vary mainly with mobility (μ). Therefore, in the following, α is also referred to as mobility.

Referring to FIG. 10, the first sensing driving period SDP1 and the second sensing driving period SDP2 are used to simultaneously sense the threshold voltage and mobility of the driving transistor DRT in the same first subpixel SP1. As a sensing driving period, it may be temporally separated by one or more active periods during which driving for image display is performed.

Each of the first sensing driving period SDP1 and the second sensing driving period SDP2 may be included in different blank periods separated by one or more active periods. That is, each of the first sensing driving period SDP1 and the second sensing driving period SDP2 may be a timing at which the RT sensing process proceeds.

Hereinafter, a sensing driving method for the advanced real-time sensing (ARTS) described above with reference to FIG. 10 will be exemplarily described in more detail with reference to FIGS. 11 and 12.

In the following, the first sub-pixel SP1 is taken as an example. The drain node or source node of the second transistor T2 included in the first subpixel SP1 is electrically connected to the first reference voltage line RVL1 among the plurality of reference voltage lines RVL. In addition, the drain node or the source node of the first transistor T1 included in the first subpixel SP1 is electrically connected to the first data line DL1 among the plurality of data lines DL.

11 and 12 are driving timing diagrams for advanced real-time sensing (ARTS) of the organic light emitting display device 100 according to embodiments of the present invention.

Each of the two or more sensing driving periods SDP1 and SDP2 for advanced real-time sensing (ARTS) may include initialization periods S1110a and S1110b, tracking periods S1120a and S1120b, and sampling periods S1130a and S1130b. .

In the initialization periods S1110a and S1110b, voltages of each of the first node N1 and the second node N2 of the driving transistor DRT are sensed driving data voltages Vdata_sen1, Vdata_sen2 and sensing driving reference voltages VpreS1. , VpreS2).

The tracking periods S1120a and S1120b are periods in which the voltage of the second node N2 of the driving transistor DRT is boosted for a certain boosting time Δt. At this time, the voltage rise rate of the second node N2 of the driving transistor DRT is proportional to the mobility of the driving transistor DRT.

The sampling periods S1130a and S1130b are periods for measuring (sensing) the voltage of the second node N2 of the driving transistor DRT, which is raised for a certain boosting time Δt, through the first reference voltage line RVL1. to be.

In the tracking periods S1120a, S1120b and the sampling periods S1130a, S1130b, the second transistor T2 is turned on by the sense signal SENSE of the turn-on level voltage, so the first reference voltage line ( The voltage Vrvl of RVL1 may correspond to the voltage of the second node N2 of the driving transistor DRT.

Referring to FIG. 11, during the initialization period S1110a of the first sensing driving period SDP1, the first transistor T1 is turned on by the scan signal SCAN of the turn-on level voltage, and the first data The first sensing driving data voltage Vdata_sen1 supplied to the line DL1 is applied to the first node N1 of the driving transistor DRT. Then, the second transistor T2 is turned on by the sense signal SENSE of the turn-on level voltage, the reference switch SPRE for sensing driving is turned on, and the first reference voltage VpreS1 is removed. It is supplied to one reference voltage line RVL1 and applied to the second node N2 of the driving transistor DRT.

During the initialization period S1110a among the first sensing driving period SDP1, the black data voltage may be applied before the first sensing driving data voltage Vdata_sen1 is applied to the first data line DL1. Here, the black data voltage is the digital black data BLK of FIG. 11 converted to an analog voltage, and the first sensing driving data voltage Vdata_sen1 is the first digital sensing driving data DATA_SEN1 of FIG. 11. Is converted to

Referring to FIG. 12, during the initialization period S1110b among the first sensing driving period SDP1 and the second sensing driving period SDP2, the first transistor T1 is driven by the scan signal SCAN of the turn-on level voltage. ) Is turned on, and the second sensing driving data voltage Vdata_sen2 supplied to the first data line DL1 is applied to the first node N1 of the driving transistor DRT. Then, the second transistor T2 is turned on by the sense signal SENSE of the turn-on level voltage, and the reference switch SPRE for sensing driving is turned on, so that it is different from the first reference voltage VpreS1. The second reference voltage VpreS2 is supplied to the first reference voltage line RVL1 and applied to the second node N2 of the driving transistor DRT.

During the initialization period S1110b of the second sensing driving period SDP2, the black data voltage may be applied before the second sensing driving data voltage Vdata_sen2 is applied to the first data line DL1. Here, as for the black data voltage, the digital black data BLK of FIG. 12 is converted to an analog voltage, and the second sensing driving data voltage Vdata_sen2 is the analog voltage of the second digital sensing driving data DATA_SEN2 of FIG. 12. Is converted to

11 and 12, the first sensing driving data voltage Vdata_sen1 and the second sensing driving data voltage Vdata_sen2 may be the same voltage value, and a compensator COMP or the like may already know the voltage value. .

11 and 12, as described above, during the initialization period S1110b among the first sensing driving period SDP1 and the second sensing driving period SDP2, the first reference voltage VpreS1 is different from the first reference voltage VpreS1. 2 A reference voltage VpreS2 may be applied to the first reference voltage line RVL1.

As described above, the organic light emitting display device 100 according to embodiments of the present invention uses different sensing driving reference voltages VpreS1 and VpreS2 in each of two or more different sensing driving periods SDP1 and SDP2. After two or more different sensing driving periods SDP1 and SDP2 are performed, the threshold voltage and mobility may be simultaneously calculated.

That is, in the organic light emitting display device 100 according to the exemplary embodiments of the present invention, after two or more different sensing driving periods SDP1 and SDP2 are performed, two different equations (3) having Vth and α as unknowns The above is generated, so that the threshold voltage and mobility can be calculated simultaneously.

As described above, during the initialization period S1110a among the first sensing driving period SDP1, the first sensing driving data voltage Vdata_sen1 is applied to the first data line DL1 and the second sensing driving period SDP2. ) During the initialization period S1110b, when the second sensing driving data voltage Vdata_sen2 is applied to the first data line DL1, the first sensing driving data voltage Vdata_sen1 and the second sensing driving data voltage. (Vdata_sen2) may be the same. If two or more different expressions (3) having Vth and α as unknowns can be generated, the first sensing driving data voltage Vdata_sen1 and the second sensing driving data voltage Vdata_sen2 may be different.

Referring to FIG. 11, during the tracking period S1120a of the first sensing driving period SDP1, the first transistor T1 is turned off by the scan signal SCAN of the turn-off level voltage. Accordingly, the first node N1 of the driving transistor DRT is floated. And, during the tracking period S1120a of the first sensing driving period SDP1, the second transistor T2 is maintained in the turn-on state by the sense signal SENSE of the turn-on level voltage, but the reference for sensing driving The switch SPRE is turned off and the first reference voltage VpreS1 is not supplied to the first reference voltage line RVL1, so that the second node N2 of the driving transistor DRT is floated.

The tracking period S1120a of the first sensing driving period SDP1 described above is performed for a predetermined boosting time Δt.

During the tracking period (S1120a) of the first sensing driving period (SDP1), that is, during the predetermined boosting time (Δt) after the initialization period (S1110a) of the first sensing driving period (SDP1), the removal of the driving transistor (DRT) Since the second node N2 is in a floating state, the voltage rises from the first reference voltage VpreS1 of the first reference voltage line RVL1 electrically connected to the second node N2 of the driving transistor DRT.

During the tracking period S1120a of the first sensing driving period SDP1, that is, during the predetermined boosting time Δt after the initialization period S1110a of the first sensing driving period SDP1, the first reference voltage line RVL1 ), The voltage rise value is ΔV1.

After the tracking period S1120a of the first sensing driving period SDP1 has elapsed for the boosting time Δt, the raised voltage of the first reference voltage line RVL1 is Vsen1 (= VpreS1 + ΔV1).

During the first sensing driving period SDP1, when the tracking period S1120a is completed, that is, when a predetermined boosting time Δt elapses after the initialization period S1110a, the sampling step S1130a is performed.

In the sampling step S1130a during the first sensing driving period SDP1, the sampling switch SAM is turned on, and the analog-to-digital converter ADC is electrically connected to the first reference voltage line RVL1.

In the sampling step S1130a during the first sensing driving period SDP1, the analog-to-digital converter ADC senses the voltage Vrvl of the first reference voltage line RVL1, and the sensed voltage Vsen1 is assigned to the digital value. It is converted to the corresponding first sensing value and output.

In this case, the sensed voltage Vsen1 of the first reference voltage line RVL1 by the analog-to-digital converter ADC is a voltage VpreS1 + ΔV1 increased by ΔV1 from the first reference voltage VpreS1.

Referring to FIG. 12, during the tracking period S1120b of the second sensing driving period SDP2, the first transistor T1 is turned off by the scan signal SCAN of the turn-off level voltage. Accordingly, the first node N1 of the driving transistor DRT is floated. And, during the tracking period S1120b of the second sensing driving period SDP2, the second transistor T2 is maintained in the turn-on state by the sense signal SENSE of the turn-on level voltage, but the reference for sensing driving The switch SPRE is turned off and the second reference voltage VpreS2 is not supplied to the first reference voltage line RVL1, so that the second node N2 of the driving transistor DRT is floated.

Of the above-described second sensing driving period SDP2, the tracking period S1120b proceeds for a predetermined boosting time Δt.

During the tracking period (S1120b) of the second sensing driving period (SDP2), that is, during the predetermined boosting time (Δt) after the initialization period (S1110b) of the second sensing driving period (SDP2), the removal of the driving transistor (DRT) Since the second node N2 is in the floating state, the voltage rise of the first reference voltage line RVL1 electrically connected to the second node N2 of the driving transistor DRT proceeds from the second reference voltage VpreS2.

During the tracking period S1120b of the second sensing driving period SDP2, that is, during the predetermined boosting time Δt after the initialization period S1110b of the second sensing driving period SDP2, the first reference voltage line RVL1 ), The voltage rise value is ΔV2.

After the tracking period S1120b of the second sensing driving period SDP2 has elapsed during the boosting time Δt, the raised voltage of the first reference voltage line RVL1 is Vsen2 (= VpreS2 + ΔV2).

During the second sensing driving period SDP2, when the tracking period S1120b is completed, that is, when a predetermined boosting time Δt elapses after the initialization period S1110b, the sampling step S1130b is performed.

In the sampling step S1130b during the second sensing driving period SDP2, the sampling switch SAM is turned on, and the analog-to-digital converter ADC is electrically connected to the first reference voltage line RVL1.

In the sampling step S1130b during the second sensing driving period SDP2, the analog-to-digital converter ADC senses the voltage Vrvl of the first reference voltage line RVL1, and the sensed voltage Vsen2 is assigned to the digital value. Convert to the corresponding second sensing value and output.

In this case, the sensed voltage Vsen2 of the first reference voltage line RVL1 by the analog-to-digital converter ADC is a voltage VpreS2 + ΔV2 that is increased by ΔV2 from the second reference voltage VpreS2.

Based on the first sensing value obtained in the first sensing driving period SDP1 and the second sensing value obtained in the second sensing driving period SDP2, the mobility of the driving transistor DRT in the first subpixel SP1 (μ) ) And the threshold voltage Vth, respectively, may be calculated.

When the compensation value for mobility (μ) is G and the compensation value for threshold voltage (Vth) is OFS, the first subpixel through the first data line DL1 by the data driving circuit 120 The data voltage (Vdata_comp) for driving the image supplied to (SP1) may correspond to a value obtained by multiplying the original data voltage (Vdata) by G and adding OFS as an offset (that is, Vdata_comp = G * Vdata + OFS) ).

That is, according to the compensation value of the mobility (μ) and the compensation value of the threshold voltage (Vth), the gain (G) and the offset (OFS) of the image driving data voltage (Vdata_comp) supplied to the first sub-pixel (SP1) This can be changed.

Accordingly, the gain G and the offset OFS of the image driving data voltage Vdata_comp supplied to the first subpixel SP1 are the mobility of the driving transistor DRT included in the first subpixel SP1 ( μ) and threshold voltage (Vth).

For the method of simultaneously sensing the threshold voltage (Vth) and the mobility (μ) through the advanced real-time sensing (ARTS) described above, the formula (1), formula (2) and formula (3) based calculation method It will be briefly explained again from the viewpoint.

During the first sensing driving period SDP1, after sensing driving for the first subpixel SP1 is performed using the first sensing driving data voltage Vdata_sen1 and the first reference voltage VpreS1, the second transistor T2 After the first sensing value, which is a digital value for the sensing voltage Vsen1 of the first reference voltage line RVL1 electrically connected to the second node N1 of the driving transistor DRT through), a compensator COMP By substituting the known values (Vdata_sen1, VpreS1, C, Δt) and the measured value (Vsen1) into the above equations (1) to (3), the following equations (4) to (6) can be obtained. have. In equations (4) to (5), Id1 is a current flowing through the drain node N3 of the driving transistor DRT during the first sensing driving period SDP1. In Eq. (6), the unknowns are Vth (threshold voltage) and α (items including mobility).

After the first sensing driving period SDP1, during the second sensing driving period SDP2 of different timing, the first subpixel SP1 is used using the second sensing driving data voltage Vdata_sen2 and the second reference voltage VpreS2. ), The sensing voltage Vsen2 of the first reference voltage line RVL1 electrically connected to the second node N1 of the driving transistor DRT through the second transistor T2 is performed. After the value of the second sensing value is obtained, the compensator (COMP) substitutes the known values (Vdata_sen2, VpreS2, C, Δt) and the measured value (Vsen2) into the equations (1) to (3). The following equations (7) to (9) can be obtained. In equations (7) to (8), Id2 is a current flowing through the drain node N3 of the driving transistor DRT during the second sensing driving period SDP2. In Eq. (9), the unknowns are Vth (threshold voltage) and α (including mobility).

Thereafter, the compensator COMP solves the simultaneous equations including Equations (6) and (9) and calculates two unknowns (Vth, α) as solutions, thereby threshold voltage (Vth) of the driving transistor (DRT). ) And α can be calculated, and mobility (μ) can be calculated from α.

According to the above-described advanced real-time sensing (ARTS), by using a variable technique of the sensing driving reference voltage (VpreS) and the RT sensing driving method, the movement of the driving transistor (DRT) in the first subpixel SP1 during image driving The degree (μ) and the threshold voltage (Vth) can be sensed simultaneously.

Also, the compensator COMP may calculate compensation values for the mobility μ and the threshold voltage Vth of the driving transistor DRT.

Thereafter, the controller 140 changes the image driving data to be supplied to the first sub-pixel SP1 by using compensation values for mobility (μ) and threshold voltage (Vth) to provide the data driving circuit 120. You can.

When the compensation value for mobility (μ) is G and the compensation value for threshold voltage (Vth) is OFS, the first subpixel through the first data line DL1 by the data driving circuit 120 The data voltage (Vdata_comp) for driving the image supplied to (SP1) may correspond to a value obtained by multiplying the original data voltage (Vdata) by G and adding OFS as an offset (that is, Vdata_comp = G * Vdata + OFS) ).

In the following, the driving method for the above-described advanced real-time sensing (ARTS) will be briefly described again.

13 is a flowchart of a driving method for advanced real-time sensing (ARTS) of the organic light emitting display device 100 according to embodiments of the present invention.

Referring to FIG. 13, a driving method for advanced real-time sensing (ARTS) of the organic light emitting display device 100 according to embodiments of the present invention includes any first subpixel (among a plurality of subpixels SP) A first sensing driving step (S1310) of supplying a first reference voltage (VpreS1) to a first reference voltage line (RVL1) electrically connected to a drain node or a source node of the second transistor (T2) included in SP1); After the first sensing driving step S1310, the first reference voltage to the first reference voltage line RVL1 electrically connected to the drain node or the source node of the second transistor T2 included in the first subpixel SP1 ( It may include a second sensing driving step (S1320) for supplying a second reference voltage (VpreS2) different from VpreS1).

The first sensing driving step (S1310) includes an initializing step (S1110a), a tracking step (S1120a) that is performed for a predetermined boosting time (Δt) after the initializing step (S1110a), and a boosting time (after the initializing step (S1110a)). It may include a sampling step (S1130a) that proceeds at the time △ t) has elapsed.

The second sensing driving step (S1320) includes an initializing step (S1110b), a tracking step (S1120b) that is performed for a predetermined boosting time (Δt) after the initializing step (S1110b), and a boosting time () after the initializing step (S1110b). It may include a sampling step (S1130b) that proceeds at the time △ t) has elapsed.

During the initialization step S1110a of the first sensing driving step S1310, the organic light emitting display device 100 supplies the first reference voltage VpreS1 to the first reference voltage line RVL1, and the first data line DL1. ), The first sensing driving data voltage Vdata_sen1 may be supplied.

During the initialization step (S1110b) of the second sensing driving step (S1320), the organic light emitting display device 100 uses a second reference voltage (VpreS2) different from the first reference voltage (VpreS1) as the first reference voltage line (RVL1). The second sensing driving data voltage Vdata_sen2 equal to the first sensing driving data voltage Vdata_sen1 may be supplied to the first data line DL1.

During the tracking step S1120a of the first sensing driving step S1310, the voltage rise of the first reference voltage line RVL1 may proceed from the first reference voltage VpreS1.

During the tracking step S1120b of the second sensing driving step S1320, the voltage rise of the first reference voltage line RVL1 may proceed from the second reference voltage VpreS2.

During the sampling step S1130a of the first sensing driving step S1310, the analog-to-digital converter ADC may sense the voltage Vrvl of the first reference voltage line RVL1 and output a first sensing value.

During the sampling step S1130b of the second sensing driving step S1320, the analog-to-digital converter ADC senses the voltage Vrvl of the first reference voltage line RVL1 to output a second sensing value.

Referring to FIG. 13, after the first sensing driving step (S1310) and the second sensing driving step (S1320), the simultaneous sensing step (S1330) and the simultaneous compensation processing step (S1340) may be performed.

In the simultaneous sensing step (S1330), the organic light emitting display device 100 is based on the first sensing value obtained in the first sensing driving step (S1310) and the second sensing value obtained in the second sensing driving step (S1320). The mobility and threshold voltage of the driving transistor DRT in one sub-pixel SP1 may be sensed simultaneously. As described above, the simultaneous sensing may be performed by obtaining a solution of a simultaneous equation.

In the simultaneous sensing step (S1330), the organic light emitting display device 100 calculates the compensation values of the mobility and threshold voltage of the driving transistor DRT in the first subpixel SP1 and stores them in the memory MEM. You can.

In the simultaneous compensation processing step (S1340), the organic light emitting display device 100, the image driving data to be supplied to the first sub-pixel (SP1), based on the compensation values of the mobility and threshold voltage of the driving transistor (DRT) The voltage gain and offset may be changed and supplied to the first data line DL1.

The gain and offset of the data voltage for driving the image may be changed according to changes in the mobility μ and the threshold voltage Vth of the driving transistor DRT included in the first subpixel SP1.

The driving circuit 111 that provides a driving method for the above-mentioned progressive real-time sensing (ARTS) will be briefly described above.

14 is a diagram illustrating a driving circuit 111 for advanced real-time sensing (ARTS) of the organic light emitting display device 100 according to embodiments of the present invention.

Referring to FIG. 14, the driving circuit 111 for advanced real-time sensing (ARTS) of the organic light emitting display device 100 according to embodiments of the present invention includes any first of a plurality of subpixels SP A data driving circuit 120 for supplying a data voltage (Vdata_sen) for sensing driving to a first data line DL1 electrically connected to a drain node or a source node of the first transistor T1 included in the subpixel SP1; , Supplying a reference voltage to supply a reference voltage for sensing driving VpreS to a first reference voltage line RVL1 electrically connected to a drain node or a source node of the second transistor T2 included in the first subpixel SP1 Circuit 1400 may be included.

The reference voltage supply circuit 1400 may supply the first reference voltage VpreS1 to the first reference voltage line RVL1 during the initialization period S1110a of the first sensing driving period SDP1.

The data driving circuit 120 may supply the first sensing driving data voltage Vdata_sen1 to the first data line DL1 during the initialization period S1110a of the first sensing driving period SDP1.

The reference voltage supply circuit 1400 is the first reference voltage VpreS1 as the first reference voltage line RVL1 during the initialization period S1110b among the first sensing driving period SDP1 and the second sensing driving period SDP2. It may supply a second reference voltage (VpreS2) different from.

The data driving circuit 120 is the second sensing driving data equal to the first sensing driving data voltage Vdata_sen1 as the first data line DL1 during the initialization period S1110b of the second sensing driving period SDP2. The voltage Vdata_sen2 can be supplied.

According to the embodiments of the present invention described above, there is an effect of providing a driving circuit 111, an organic light emitting display device 100 and a driving method that enable accurate sensing and compensation while reducing the time required for sensing. .

In addition, according to embodiments of the present invention, there is an effect of providing a driving circuit 111, an organic light emitting display device 100 and a driving method capable of sensing a threshold voltage of a transistor in real time during image driving.

In addition, according to embodiments of the present invention, an effect of providing a driving circuit 111, an organic light emitting display device 100 and a driving method capable of simultaneously sensing the threshold voltage and mobility of a transistor while driving an image is provided. have.

In addition, according to embodiments of the present invention, it is possible to immediately compensate for a threshold voltage change during image driving, and by simultaneously sensing the threshold voltage and mobility in the same sensing driving process, reducing the time or number of times required for the sensing driving process. It has the effect of giving.

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 combine combinations in a range that does not depart from the essential characteristics of the present invention. , Various modifications and variations such as separation, substitution and change will be possible. Therefore, 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 scope of protection of the present invention should be interpreted by the claims below, and all technical spirits within the scope equivalent thereto should be interpreted as being included in the scope of the present invention.

100: organic light emitting display device
110: display panel
120: data driving circuit
130: gate driving circuit
140: controller
410: sensing circuit
1400: Reference voltage supply circuit

Claims (15)

A display panel in which a plurality of data lines and a plurality of gate lines are arranged, a plurality of reference voltage lines are arranged, and a plurality of sub-pixels are arranged;
A data driving circuit driving the plurality of data lines; And
And a gate driving circuit for driving the plurality of gate lines,
The plurality of sub-pixels,
An organic light emitting diode, a driving transistor for driving the organic light emitting diode, a first transistor electrically connected between a first node of the driving transistor and a corresponding data line among the plurality of data lines, and a second of the driving transistor A second transistor electrically connected between a node and a corresponding reference voltage line among the plurality of reference voltage lines, and a capacitor electrically connected between the first node and the second node of the driving transistor,
A reference switch for sensing driving electrically connected between a reference voltage supply node and the reference voltage line;
An analog-to-digital converter that senses the voltage of the reference voltage line; And
Further comprising a sampling switch electrically connected between the reference voltage line and the analog-to-digital converter,
A drain node or a source node of the second transistor included in any first subpixel among the plurality of subpixels is electrically connected to a first reference voltage line among the plurality of reference voltage lines,
During the initialization period during the first sensing driving period, a first reference voltage is applied to the first reference voltage line,
An organic light emitting display device wherein a second reference voltage different from the first reference voltage is applied to the first reference voltage line during an initialization period during a second sensing driving period different from the first sensing driving period.
According to claim 1,
Each of the first sensing driving period and the second sensing driving period includes an organic light emitting display device included in a different blank period.
According to claim 1,
A drain node or a source node of the first transistor included in the first subpixel is electrically connected to a first data line among the plurality of data lines,
During the initialization period of the first sensing driving period, a first sensing driving data voltage is applied to the first data line,
During the initialization period of the second sensing driving period, an organic light emitting display device in which a second sensing driving data voltage equal to the first sensing driving data voltage is applied to the first data line.
According to claim 3,
During the first sensing driving period, during a predetermined boosting time after an initialization period, a voltage rise of the first reference voltage line proceeds from the first reference voltage,
During the boosting time after an initialization period during the second sensing driving period, the first reference voltage line is an organic light emitting display device in which a voltage rises at the second reference voltage different from the first reference voltage.
According to claim 4,
When the boosting time has elapsed after the initialization period during the first sensing driving period, the sampling switch is turned on so that the first reference voltage line is electrically connected to the analog digital converter, and the analog digital converter is Sensing the voltage of the first reference voltage line to output the first sensing value,
During the second sensing driving period, when the boosting time has elapsed after the initialization period, the sampling switch is turned on so that the first reference voltage line is electrically connected to the analog digital converter, and the analog digital converter is An organic light emitting display device that senses the voltage of the first reference voltage line and outputs a second sensing value.
The method of claim 5,
An organic light emitting display device in which the gain and offset of the image driving data voltage supplied to the first subpixel are changed based on the first sensing value and the second sensing value.
The method of claim 6,
An organic light emitting display device in which gain and offset of a data voltage for driving an image supplied to the first subpixel are changed according to a change in mobility and threshold voltage of the driving transistor included in the first subpixel.
A display panel in which a plurality of data lines and a plurality of gate lines are arranged, a plurality of reference voltage lines are arranged, and a plurality of sub-pixels are arranged; A data driving circuit driving the plurality of data lines; And a gate driving circuit for driving the plurality of gate lines, wherein the plurality of sub-pixels includes an organic light emitting diode, a driving transistor for driving the organic light emitting diode, a first node of the driving transistor, and the plurality of Of the data line of the first transistor electrically connected between the data line, the second node of the driving transistor and the second transistor electrically connected between the reference voltage line of the plurality of reference voltage lines, and the driving transistor of the In the driving method of the organic light emitting display device including a capacitor electrically connected between the first node and the second node,
A first sensing driving step of supplying a first reference voltage to a first reference voltage line electrically connected to a drain node or a source node of the second transistor included in any one of the plurality of subpixels; And
After the first sensing driving step, a second reference voltage different from the first reference voltage is supplied to the first reference voltage line electrically connected to a drain node or a source node of the second transistor included in the first subpixel. Driving method of the organic light emitting display device comprising a second sensing driving step.
The method of claim 8,
A drain node or a source node of the first transistor included in the first subpixel is electrically connected to a first data line among the plurality of data lines,
Each of the first sensing driving step and the second sensing driving step is an initialization step, a tracking step that is performed for a predetermined boosting time after the initialization step, and a sampling step that is performed when the boosting time has elapsed since the initialization step. Including,
During the initializing step of the first sensing driving step,
Supplying the first reference voltage to the first reference voltage line, and supplying a first sensing data voltage to the first data line,
During the initialization step of the second sensing driving step,
An organic supplying the second reference voltage different from the first reference voltage to the first reference voltage line, and supplying a second sensing driving data voltage equal to the first sensing driving data voltage to the first data line. Method of driving a light emitting display device.
The method of claim 9,
During the tracking step of the first sensing driving step, the voltage of the first reference voltage line is increased from the first reference voltage,
During the tracking of the second sensing driving step, the first reference voltage line is a method of driving an organic light emitting display device in which the voltage rises at the second reference voltage different from the first reference voltage.
The method of claim 10,
During the sampling step of the first sensing driving step, the analog-to-digital converter senses the voltage of the first reference voltage line and outputs a first sensing value,
During the sampling step of the second sensing driving step, the analog-to-digital converter senses the voltage of the first reference voltage line and outputs a second sensing value.
The method of claim 11,
After the first sensing driving step and the second sensing driving step,
Comprising a compensation processing step of changing the gain and offset of the data voltage for driving the image to be supplied to the first sub-pixel based on the first sensing value and the second sensing value and supplying it to the first data line. Method of driving a light emitting display device.
The method of claim 8,
The first sensing driving step is performed in the first blank period,
The second sensing driving step is a method of driving an organic light emitting display device that is performed in a second blank period different from the first blank period.
A display panel in which a plurality of data lines and a plurality of gate lines are arranged, a plurality of reference voltage lines are arranged, and a plurality of sub-pixels are arranged; A data driving circuit driving the plurality of data lines; And a gate driving circuit for driving the plurality of gate lines, wherein the plurality of sub-pixels includes an organic light emitting diode, a driving transistor for driving the organic light emitting diode, a first node of the driving transistor, and the plurality of Of the data line of the first transistor electrically connected between the data line, the second node of the driving transistor and the second transistor electrically connected between the reference voltage line of the plurality of reference voltage lines, and the driving transistor of the In the driving circuit of the organic light emitting display device including a capacitor electrically connected between the first node and the second node,
A data driving circuit for supplying a data voltage for sensing driving to a first data line electrically connected to a drain node or a source node of the first transistor included in any one of the plurality of subpixels; And
And a reference voltage supply circuit that supplies a reference voltage to a first reference voltage line electrically connected to a drain node or a source node of the second transistor included in the first subpixel,
The reference voltage supply circuit,
During the initialization period during the first sensing driving period, a first reference voltage is supplied to the first reference voltage line,
A driving circuit for supplying a second reference voltage different from the first reference voltage to the first reference voltage line during an initialization period of a second sensing driving period different from the first sensing driving period.
According to claim 1,
The data driving circuit,
During the initialization period during the first sensing driving period, a first sensing driving data voltage is supplied to the first data line,
During the initialization period of the second sensing driving period, a driving circuit that supplies a second sensing driving data voltage equal to the first sensing driving data voltage to the first data line.

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