KR20210042765A - Organic light emtting display device - Google Patents

Abstract

Embodiments of the present invention may provide a display device capable of preventing the degradation in image quality and a driving method thereof. The display device comprises: a display panel including a first transistor a light emitting diode receiving a driving current; a data driver supplying a data signal to a plurality of data lines; and a gate driver supplying a gate signal to a plurality of gate lines. The display is operated in a period divided into a display period in which the data signal is transmitted to the data lines within one frame period and a sensing period in which the characteristics of a pixel is sensed. The sensing period includes at least one of a first period for sensing threshold voltage information on a threshold voltage of the first transistor and a second period for sensing deterioration information on the deterioration of the light emitting diode.

Description

Display device and its driving method {ORGANIC LIGHT EMTTING DISPLAY DEVICE}

Embodiments of the present invention relate to a display device and a driving method thereof.

As the information society develops, demands for display devices for displaying images are increasing in various forms. As a display device, various display devices such as a liquid crystal display (LCD), a light emitting display (OLED), and a quantum dot light emitting display (QLED) are used. .

Among display device devices, a display device employing a light-emitting diode, which is a self-luminous element, may have excellent response speed and viewing angle due to the light-emitting diode that emits light by itself. In addition, there is an advantage in that the thickness of the display device can be implemented to be thin.

A plurality of pixels of such a display device each include a driving transistor that supplies a driving current to the light emitting diode, and the magnitude of the driving current varies depending on the characteristics of the pixel including the threshold voltage of the driving transistor included in each of the pixels. Can occur. The display device emits light by a driving current to display an image. If the driving current varies for each pixel, the image quality may deteriorate. In addition, the light emitting diode is deteriorated according to the usage time, and the image quality may be deteriorated due to the deterioration.

Accordingly, the display device can prevent the image quality from deteriorating by using a sensing signal that senses the characteristics and/or deterioration of the pixel.

Embodiments of the present invention are to provide a display device capable of preventing deterioration of image quality and a driving method thereof.

In one aspect, embodiments of the present invention include a plurality of pixels receiving a driving voltage corresponding to a data signal, a plurality of data lines electrically connected to the plurality of pixels, and a plurality of data lines electrically connected to the plurality of pixels. A gate line and a plurality of sensing lines electrically connected to at least two or more of the plurality of pixels, each of the plurality of pixels supplying a first transistor supplying a driving current corresponding to the driving voltage and a driving current A display panel including a receiving light emitting diode, a data driver supplying data signals to a plurality of data lines, and a gate driver supplying gate signals to a plurality of gate lines, wherein data signals are transmitted to the data lines within one frame period. The display period is divided into a display period and a sensing period for sensing a characteristic of a pixel, and the sensing period includes a first period for sensing threshold voltage information on the threshold voltage of the first transistor, and deterioration information on the deterioration of the light emitting diode. A display device including at least one of the sensing second periods may be provided.

In another aspect, embodiments of the present invention include a plurality of pixels receiving a driving voltage corresponding to a data signal, a plurality of data lines electrically connected to the plurality of pixels, and a plurality of data lines electrically connected to the plurality of pixels. A gate line and a plurality of sensing lines electrically connected to at least two or more pixels among the plurality of pixels, each of the plurality of pixels supplying a first transistor supplying a driving current corresponding to a driving voltage and a driving current A display panel including a receiving light emitting diode, a data driver supplying data signals to a plurality of data lines, a gate driver supplying gate signals to a plurality of gate lines, a data driver, a timing controller controlling the gate driver, and a first power supply. And a power control unit for supplying a second power supply having a voltage level lower than that of the first power source, wherein one frame period is divided into a display period in which a data signal is transmitted to a data line and a sensing period in which a characteristic of a pixel is sensed. The period includes a first period and a second period, and a voltage level of the second power source in the first period may be higher than the voltage level of the second power source in the second period.

In another aspect, exemplary embodiments of the present invention include a display device that displays an image using a first transistor receiving a driving voltage and a light emitting diode that emits light by receiving a driving current corresponding to a driving voltage from the first transistor. In the driving method, the step of displaying an image in a display period during one frame period, a first period for sensing threshold voltage information on a threshold voltage of a first transistor during a sensing period during one frame period, and for deterioration of a light emitting diode. It is possible to provide a method of driving a display device including performing at least one of the second periods for sensing deterioration information for the display device.

According to embodiments of the present invention, it is possible to provide a display device capable of preventing deterioration of image quality and a driving method thereof.

1 is a structural diagram illustrating a display device according to example embodiments.
2 is a circuit diagram illustrating an arrangement of pixels and wires in the display device illustrated in FIG. 1.
3 is a circuit diagram illustrating a pixel and an analog-to-digital converter connected to the pixel according to example embodiments.
4 is a timing diagram illustrating an operation of a display device according to example embodiments.
5 is a timing diagram illustrating a process of sensing a threshold voltage in a display device according to an exemplary embodiment of the present invention.
6 is a timing diagram illustrating a process of sensing deterioration in a display device according to an exemplary embodiment of the present invention.
7 is a timing diagram illustrating an operation of a pixel in a display device according to an exemplary embodiment of the present invention
8 is a structural diagram showing an embodiment of a data driver employed in a display device according to the present invention.
9 is a flowchart illustrating a method of driving a display device according to example embodiments.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. In adding reference numerals to elements of each drawing, the same elements may have the same numerals as possible even if they are indicated on different drawings. In addition, in describing the present invention, when it is determined that a detailed description of a related known configuration or function may obscure the subject matter of the present invention, the detailed description may be omitted. When "include", "have", "consists of" and the like mentioned in the present specification are used, other parts may be added unless "only" is used. In the case of expressing the constituent elements in the singular, the case including the plural may be included unless there is a specific explicit description.

In addition, in describing the constituent elements 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 nature, order, order, or number of the component is not limited by the term.

In the description of the positional relationship of the components, when two or more components are described as being "connected", "coupled" or "connected", the two or more components are directly "connected", "coupled" or "connected" It should be understood that "may be, but two or more components and other components may be further "interposed" to be "connected", "coupled" or "connected". Here, the other constituent elements may be included in one or more of two or more constituent elements “connected”, “coupled” or “connected” to each other.

In the description of the temporal flow relationship related to the components, the operation method or the manufacturing method, for example, the temporal precedence relationship such as "after", "after", "after", "before", etc. Alternatively, a case where a flow forward and backward relationship is described may also include a case that is not continuous unless “directly” or “directly” is used.

On the other hand, when a numerical value for a component or its corresponding information (e.g., level, etc.) is mentioned, the numerical value or its corresponding information is related to various factors (e.g., process factors, internal or external impacts, etc.) It can be interpreted as including an error range that can be caused by noise, etc.).

1 is a structural diagram illustrating a display device according to example embodiments.

Referring to FIG. 1, the display device 100 may include a display panel 110, a gate driver 120, a data driver 130, and a timing controller 140.

The display panel 110 includes a plurality of pixels generating a driving current corresponding to a data signal, a plurality of data lines DL connected to the plurality of pixels, and a plurality of gate lines GL respectively connected to the plurality of pixels. And a plurality of sensing lines SL connected to the plurality of pixels 101, respectively, wherein each of the plurality of pixels 101 includes a first transistor supplying a driving current and a light emitting diode receiving the driving current to emit light. It may include.

A plurality of gate lines GL and a plurality of data lines DL may be disposed on the display panel 110, and a plurality of pixels 101 may be connected to the plurality of gate lines GL and the data lines DL. Each pixel 101 may receive a data signal transmitted through a data line in response to a gate signal transmitted through the gate line GL. In addition, each pixel 101 may generate a driving current corresponding to the voltage level of the data signal and supply it to the light emitting diode. In addition, each pixel 101 may be connected to the sensing line SL. The sensing line SL may be connected to the pixel 101 in response to the sensing control signal. The number of sensing lines SL may be smaller than the number of data lines DL.

In addition, the display panel 110 may include a plurality of power lines supplying power to the plurality of pixels 101. However, wirings disposed on the display panel 110 are not limited thereto.

The gate driver 120 may sequentially transmit gate signals to the plurality of gate lines GL. The gate driver 120 may include one or more gate driver integrated circuits (GDIC), and may be located on only one side or both sides of the display panel 100 according to a driving method. . In addition, the gate driver 120 may be disposed in a GIP (Gate in Panel) type disposed on the display panel 110, and may be generated at the same time when a pixel circuit is generated on the display panel 110. Also, the gate driver 120 may output a sensing control signal.

The data driver 130 may be connected to a plurality of data lines DL and may supply a data signal to the plurality of data lines DL. The data driver 130 may include a plurality of integrated circuits. Each of the plurality of integrated circuits included in the data driver 130 may be referred to as a source driver. The number of source drivers may be determined according to the resolution and/or size of the display panel 110.

The timing controller 140 may receive an image signal, correct it, and output it. The image signal output from the timing controller 140 may be supplied to the data driver 130. In addition, the timing controller 140 may control the gate driver 120 and the data driver 130. In addition, the timing controller 140 operates by dividing into a display period in which a data signal is transmitted to the data line DL within a frame period and a sensing period in which a characteristic of a pixel is sensed, wherein the sensing period is a threshold of the first transistor. It may include at least one of a first period for sensing threshold voltage information for a voltage and a second period for sensing deterioration information on deterioration of the light emitting diode.

In addition, the display device 100 may include a power control circuit 150. The power control circuit 150 may supply a first power supply EVDD and a second power supply EVSS having a lower voltage level than the first power supply EVDD to the display panel 110.

FIG. 2 is a circuit diagram illustrating an arrangement of pixels and wires in the display device illustrated in FIG. 1.

Referring to FIG. 2, one of four pixels 101R, 101G, 101B, and 101W connected to one gate line GL in the display device 100 and connected to different data lines DL1 to DL4, respectively. It may be connected to the sensing line SL of. That is, four pixels 101R, 101G, 101B, and 101W may share one sensing line SL. Here, the number and color of pixels shared by one sensing line SL are not limited thereto.

Each of the four pixels 101R, 101G, 101B, and 101W is a red pixel emitting red light, a green pixel emitting green light, a blue pixel emitting blue light, and a white pixel emitting white light. It can be a pixel. In addition, in the four pixels 101R, 101G, 101B, and 101W, red, green, and blue filters are disposed on three of the four pixels emitting white light, respectively, so that the white light emitted from the pixel is red, It may be converted into red, green, and blue light by green and blue filters.

3 is a circuit diagram illustrating a pixel and an analog-to-digital converter connected to the pixel according to example embodiments.

Referring to FIG. 3, the pixel 101 may include a first transistor M1 that supplies a driving current in response to a voltage level (Vdata) of a data signal, and a light-emitting diode (LED) that emits light in response to the driving current. have. In addition, the pixel 101 has a second transistor M2 that selectively supplies a data signal to a gate electrode of the first transistor M1 in response to a gate signal, and a first transistor M1 selectively in response to a sensing control signal. The gate electrode of the third transistor M3 and the first transistor M3 and the source electrode of the first transistor M1 supplying the voltage applied to the electrode connected to the light emitting diode (LED) to the sensing line SL. It may further include a storage capacitor (Cst) connected therebetween.

The first transistor M1 may be connected to the power line VL through which the first electrode transmits the first power EVDD, and the second electrode may be connected to the first node N1. In addition, the gate electrode of the first transistor M1 may be connected to the second node N2. The first transistor M1 may allow a driving current to flow from the first electrode to the second electrode in response to the voltage level Vdata of the data signal transmitted to the second node N2. The driving current may correspond to Equation 1 below.

Here, Id means the current amount of the driving current, Vgs means the voltage difference between the gate electrode and the source electrode of the first transistor M1, and vth means the threshold voltage of the first transistor M1. In addition, k means mobility.

In the second transistor M2, a first electrode may be connected to the data line DL and a second electrode may be connected to the second node N2. Also, the gate electrode may be connected to the gate line GL. Since the second transistor M2 can transmit the gate signal to the gate electrode through the gate line GL, the data signal transmitted to the data line DL can be transmitted to the second node N2 in response to the gate signal. have.

In the third transistor M3, a first electrode may be connected to the first node N1 and a second electrode may be connected to the sensing line SL. In addition, the gate electrode may be connected to the sensing control signal line SENSE. The third transistor M3 may transmit the initialization voltages VpreR and VpreS to the first node N1 in response to the sensing control signal transmitted through the sensing control signal line SENSE. Also, the third transistor M3 may transmit the voltage of the first node N1 to the sensing line SL.

In the storage capacitor Cst, a first electrode may be connected to the first node N1 and a second electrode may be connected to the second node N2. The storage capacitor Cst may maintain a voltage between the first node N1 and the second node N2. Accordingly, the storage capacitor Cst can maintain the voltage level Vdata of the data signal transmitted to the second node N2.

In the light emitting diode LED, an anode electrode may be connected to the first node N1 and a second power source EVSS may be transmitted to the cathode electrode. Accordingly, a driving current may flow from the anode electrode to the cathode electrode.

In addition, the display device 100 includes an analog digital converter 130a on the sensing line SL, a sampling switch SAM disposed between the sensing line SL and the analog digital converter 130a, and a first initialization voltage ( A first initialization switch (RPRE) that selectively supplies VpreR) to the sensing line (SL) and a second initialization switch (SPRE) that selectively supplies a second initialization voltage (VpreS) to the sensing line (SL). have. When connected and the sampling switch SAM is turned on, a voltage charged in the sensing line SL may be transferred to the analog digital converter 130a. The charged voltage may be a sensing signal transmitted to the sensing line SL. The sensing signal may be converted into a digital signal by the analog digital converter 130a and output as sensing data.

The sampling switch SAM may be turned on within a period in which the third transistor M3 is turned on. When the third transistor M3 is turned on, the voltage of the first node N1 may be charged in the sensing line SL. In addition, when the sampling switch SAM is turned on, a voltage charged in the sensing line SL may be transmitted to the analog digital converter 130a.

A first initialization switch RPRE is connected to the sensing line SL, and a first initialization voltage VpreR may be selectively transmitted to the sensing line SL in response to an operation of the first initialization switch RPRE. When the first initialization voltage VpreR is transmitted to the sensing line SL by the first initialization switch RPRE, the sensing line SL may be initialized. During the period in which the first initialization switch RPRE is turned on, the third transistor M3 may also be turned on. In addition, the second initialization switch SPRE is connected to the sensing line SL, and the second initialization switch SPRE may selectively transmit the second initialization voltage VpreS to the sensing line SL.

The analog digital converter 130a may be connected to the sensing line SL. When the sampling switch SAM is turned on, the analog digital converter 130a may receive a sensing signal corresponding to the voltage charged in the sensing line SL from the sensing line SL. The analog digital converter 130a may convert the transmitted sensing signal, output sensing data, and transmit it to the timing controller 140.

4 is a timing diagram illustrating an operation of a display device according to example embodiments.

Referring to FIG. 4, the display device 100 may display an image including a plurality of frames. The required period for displaying one frame may be referred to as one frame period 1F.

One frame period 1F may include a display period Td and a sensing period Ts. During the display period Td, the data driver 130 may receive an image signal, generate a data signal, and supply the data signal to the pixel 101. In addition, a driving current is generated in response to a data signal supplied to the pixel 101 in the display period Td, and the generated driving current may be supplied to the light emitting diode (LED).

In the sensing period Ts, the characteristics of the pixel 101 or deterioration of the light emitting diode LED may be sensed. In addition, the image signal may not be transmitted to the data driver 130 during the sensing period Tb. The sensing period Ts may be divided into a first period Ts1 and a second period Ts2. The first period Ts1 may be a period for sensing the threshold voltage of the first transistor M1, and the second period Ts2 may be a period for sensing deterioration of the light emitting diode LED.

The characteristics of the pixel 101 or deterioration of the light emitting diode (LED) may correspond to a voltage charged in the sensing line SL during the sensing period Ts. The voltage charged in the sensing line SL sensed in the first period Ts1 may correspond to the threshold voltage of the first transistor M1 and charged in the sensing line SL sensed in the second period Ts2. The reduced voltage may correspond to the deterioration of the light emitting diode (LED).

Here, the sensing period (Ts) is shown to include the first period (Ts1) and the second period (Ts2), but is not limited thereto, and the sensing period (Ts) includes only the first period (Ts1). can do. In addition, when the sensing period Ts is operated including only the first period Ts1 and a preset time elapses, the display device 100 is configured to be separated from the first period Ts1 and the second period Ts2. ) Can be included. The preset time may be that the accumulated time of the display period Td reaches the preset time. For example, the preset time may be 1000 hours. However, it is not limited thereto.

5 is a timing diagram illustrating a process of sensing a threshold voltage in a display device according to an exemplary embodiment of the present invention.

Referring to FIG. 5, when the initialization control signal RPRE becomes high, the initialization voltage VpreR may be supplied to the sensing voltage line SSL through the first switch SW1. At this time, when the gate signal g is transmitted to the gate line GL and the sensing control signal Ssen is transmitted through the sensing signal line SENSE, the second transistor T2 and the third transistor T3 are turned on, A data voltage Vdata corresponding to the data signal may be applied to one node N1. When the data voltage Vdata is transmitted to the first node N1, the first transistor T1 may allow a driving current corresponding to the data voltage Vdata to flow to the second node N2. In addition, when the third transistor T3 is turned on while the switch SW1 is turned on, the initialization voltage VpreR may be transmitted to the second node N2.

When the switch SW1 is turned off, the second node N2 may not be supplied with the initialization voltage VpreR. At this time, when the driving current flows to the second node N2, the voltage level of the second node N2 may increase due to the driving current. In addition, when the second switch SW2 is turned on when the voltage of the second node N2 rises and saturates, the sensing voltage line SSL and the analog digital converter 121b are connected, and the sensing voltage line SSL is sensed. The voltage Vsense may be transferred to the analog digital converter 121b. When the analog digital converter 121b converts the sensing voltage Vsense into a digital signal and transmits it to the controller 140, the controller 140 may calculate the magnitude of the threshold voltage of the first transistor T1.

6 is a timing diagram illustrating a process of sensing deterioration in a display device according to an exemplary embodiment of the present invention.

Referring to FIG. 6, a gate signal gs and a sensing control signal SSen may be transmitted in a first period T1a. When the gate signal gs and the sensing control signal Ssen are transmitted, the second transistor M2 and the third transistor M3 may be turned on.

When the second transistor M2 is turned on, the data signal transmitted through the data line DL is transmitted to the first node N1, and the data signal may be transmitted to the gate of the first transistor. In addition, when the third transistor M3 is turned on, the first node N1 may be connected to the sensing line SL.

Since the gate signal gs and the sensing control signal Ssen are not transmitted during the second period T2a, the second transistor M2 and the third transistor M3 may be turned off. In the second period T2a, the voltage of the data signal is applied to the first node N1, so that the driving current flows to the first node N1 by the first transistor M1, the voltage of the first node N1 The level may rise.

In the third period T3a, the gate signal gs and the sensing control signal Ssen may be transmitted. When the gate signal gs and the sensing control signal Ssen are transmitted, the second transistor M2 and the third transistor M3 may be turned on. When the third transistor M3 is turned on, the second node N2 and the sensing line SL are connected so that a current flows through the second node N2 to the sensing line SL. An integrator is connected to the sensing line SL, and a voltage applied to the light emitting diode LED can be calculated by integrating the magnitude of the driving current in the integrator. In addition, deterioration of the light emitting diode (LED) may be sensed by using the voltage applied to the light emitting diode (LED).

7 is a timing diagram illustrating an operation of a pixel in a display device according to an exemplary embodiment of the present invention.

Referring to FIG. 7, a gate signal gs and a sensing control signal Ssen may be transmitted in a first period T1b. The gate signal and the sensing control signal may be transmitted in a high state, and the second transistor M2 and the third transistor M3 may be turned on by the gate signal gs and the sensing control signal Ssen. Also, the second initialization switch SPRE may be turned on.

When the second transistor M2 is turned on, a data signal transmitted to the data line DL may be transmitted to the second node N2. In addition, when the third transistor M3 is turned on, the sensing line SL and the first node N1 may be connected. Since the second initialization switch SPRE is turned on, the second initialization voltage VpreS is transmitted to the sensing line SL, so that the first node N1 may be initialized by the second initialization voltage VpreS.

The driving current flows by the first transistor M1 in response to the voltage applied to the first node N1 and the second node N2, and the light emitting diode LED can emit light in response to the driving current. .

In addition, in the second period T2b, the gate signal gs and the sensing control signal Ssen may be transmitted in a low state. When the gate signal gs and the sensing control signal Ssen are transmitted in a low state, the second transistor M2 and the third transistor M3 may be turned off. Also, the second initialization switch SPRE may be turned off. When the second transistor M2 and the third transistor M3 are turned off, the data signal is not transmitted to the first node N1 and the second initialization voltage VpreS is not transmitted to the second node N2. Even if not, the voltage of the first node N1 and the second node N2 is maintained by the storage capacitor Cst, so that the first transistor M1 is driven with the same amount as the driving current generated in the first period T1b. Since current can be generated, the light emitting diode LED in the second period T2b may emit light having the same intensity as the light emitted in the first period T1b.

In addition, the voltage of the second power source EVSS increases during the third period T3b. The voltage of the second power source EVSS can be adjusted by the power control circuit 150. When the voltage of the second power source EVSS increases, the driving current may not flow through the light emitting diode LED.

And, in the fourth period T4b, first, after the first initialization switch RPRE is turned on, the gate signal gs and the sensing control signal Ssen are in a high state, so that the second transistor M2 and the third transistor are in a high state. Transistor M3 may be turned on. When the first initialization switch RPRE is turned on, the sensing line SL is initialized by the first initialization voltage VpreR. In addition, when the second transistor M2 is turned on, a driving current flows through the first transistor M1.

When the driving current flows, the voltage of the second node N2 increases. The driving current flows until the difference between the voltage of the second node N2 and the voltage of the first node N1 becomes the difference between the threshold voltage of the first transistor M1. Accordingly, the threshold voltage of the first transistor M1 may be charged in the storage capacitor Cst. In addition, since the third transistor M3 is turned on, the voltage of the second node N2 may be transmitted to the sensing line SL to the third transistor M3. And, when the sampling switch (SAM) is turned on, the voltage of the sensing line SL may be transmitted to the analog-to-digital converter 130a, and the analog-to-digital converter 130a converts the voltage of the sensing line SL into a digital signal. It can be transmitted to the timing controller 140.

Accordingly, while displaying an image on the display panel 110, the threshold voltage may be sensed. Here, the first period T1b and the second period T2b may be included in the display period Td of FIG. 3, and the third period T3b and the fourth period T4b are the sensing period Ts of FIG. 3. Can be included in

In addition, when the accumulated time of the display period of the display panel 110 reaches a preset time, a fifth period T5b and a sixth period T6b may be included. That is, when the accumulated time of the display period Td does not reach a preset time, the first to fourth periods T1b to T4b are repeated, and the accumulated time of the display period Td is at the preset time. When reached, the first to sixth periods T1b to T6b are repeated.

In the fifth period T5b, the voltage of the second power source EVSS may be lowered. The voltage of the second power EVSS may be the voltage of the second power EVSS delivered in the display period Td. The gate signal gs and the sensing control signal Ssen may be maintained in a high state. At this time, a current flows through the light-emitting diode (LED), so that the voltage applied to the light-emitting diode (LED) is lowered. In addition, the voltage applied to the light emitting diode (LED) varies according to the degree of deterioration. In addition, the voltage applied to the light emitting diode LED is transmitted to the sensing line SL.

In addition, in the sixth period T6b, the gate signal gs and the sensing control signal Ssen may be in a low state. In addition, when the sampling switch SAM is turned on, a voltage applied to the light emitting diode LED may be transferred to the analog-to-digital converter 130a. The analog-to-digital converter 130a may convert a voltage applied to a light emitting diode (LED) into a digital signal.

Unlike the process of sensing the deterioration illustrated in FIG. 5, the deterioration may be sensed using the analog-to-digital converter 130a without using an integrator. Accordingly, the threshold voltage of the first transistor M1 and the deterioration of the light emitting diode LED can be sensed without the use of an integrator. In addition, it is possible to further shorten the time required to sense the deterioration of the light emitting diode (LED).

In addition, the gate signal gs and the sensing control signal Ssen may have the same waveform. The gate signal gs and the sensing control signal Ssen may use the same signal. When the gate signal gs and the sensing control signal Ssen are the same signal, the gate signal gs and the sensing control signal Ssen can be transmitted through the same line, so that the number of lines disposed on the display panel 110 is determined. As a result, the aperture ratio of the display panel 110 can be increased. In addition, since only the gate signal gs can be output from the gate driver 120, the size of the gate driver 120 can be reduced.

8 is a structural diagram showing an embodiment of a data driver employed in a display device according to the present invention.

Referring to FIG. 8, the data driver 130 may include an analog-to-digital converter 130a and a digital-to-analog converter 130b.

The data driver 130 may be connected to the timing controller 140 to receive a signal. In addition, the analog digital converter 130a of the data driver 130 may receive a sensing signal from the pixel 101 and convert it into a digital signal to output sensing data. The sensing data corresponding to the sensing signal sensed in the first period Ts1 includes threshold voltage information on the threshold voltage, and the sensing data corresponding to the sensing signal sensed in the second period Ts2 is It may include deterioration information about deterioration.

The digital-to-analog converter 130b of the data driver 130 may convert an image signal received from the timing controller 140 into an analog signal and output a data signal. The analog-to-digital converter 130a may be connected to the sensing line SL, and the digital-to-analog converter 130b may be connected to the data line DL.

Also, the data driver 130 may be one of a plurality of source drivers.

9 is a flowchart illustrating a method of driving a display device according to example embodiments.

Referring to FIG. 9, the display device 100 may display an image in the display period Td during one frame period 1F. (S900) In the display period Td, the timing controller 140 is a data driver. An image signal is supplied to 130, and the data driver 130 may generate a data signal using the supplied image signal. The timing controller 140 may receive an image signal from an external set, correct it, and supply it to the data driver 130.

The display characteristics may be sensed during the sensing period Ts during the period of one frame 1F. (S910) The display characteristics may be a threshold voltage of the first transistor M1 and deterioration of the light emitting diode LED. However, it is not limited thereto. The sensing period Ts is a first period Ts1 for sensing threshold voltage information on the threshold voltage of the first transistor M1 and a second period Ts2 for sensing deterioration information on the deterioration of the light emitting diode LED. It may include at least one of. The second period Ts2 may be performed when the accumulated time of the display period reaches a preset time. The timing controller 140 may use threshold voltage information and deterioration information sensed in the first period Ts1 and the second period Ts2 to correct the image signal.

In addition, the display device 100 may be driven by receiving a first power supply EVDD and a second power supply EVSS having a lower voltage level than the first power supply EVDD. The voltage level of the second power source EVSS in the first period Ts1 may be set higher than the voltage level of the second power source EVSS in the second period Ts2. In the first period Ts1, the driving current may not be supplied to the light emitting diode LED. In addition, the voltage level of the second power source EVSS in the second period Ts2 may be the same as the voltage level of the second power source EVSS in the display period Td.

The above description is merely illustrative of the technical idea of the present invention, and those of ordinary skill in the art to which the present invention pertains will be able to make various modifications and variations without departing from the essential characteristics of the present invention. In addition, since the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but are intended to describe the technical idea, the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

100: display device
101: pixel
120: gate driver
130: data driver
140: timing controller
150: power control circuit

Claims (19)

Among a plurality of pixels receiving a driving voltage corresponding to a data signal, a plurality of data lines electrically connected to the plurality of pixels, a plurality of gate lines electrically connected to the plurality of pixels, and the plurality of pixels And a plurality of sensing lines electrically connected to at least two or more pixels, each of the plurality of pixels including a first transistor supplying a driving current corresponding to the driving voltage and a light emitting diode receiving the driving current Display panel;
A data driver supplying the data signal to the plurality of data lines; And
Including a gate driver for supplying a gate signal to the plurality of gate lines,
Operates by dividing into a display period in which a data signal is transmitted to the data line and a sensing period for sensing characteristics of the pixel within one frame period, wherein the sensing period includes threshold voltage information on the threshold voltage of the first transistor. A display device including at least one of a first period for sensing and a second period for sensing deterioration information about deterioration of the light emitting diode.
The method of claim 1,
The second period is included in the sensing period when the accumulated time of the display period reaches a preset time.
The method of claim 1,
A first power source and a second power source having a lower voltage level than the first power source are supplied to the display panel, wherein the voltage level of the second power source in the first period is And a power control circuit for supplying a power higher than a voltage level of power in the second period.
The method of claim 3,
A display device in which the voltage level of the second power source in the second period is the same as the voltage level of the second power source in the display period.
The method of claim 3,
The threshold voltage information corresponds to a voltage charged in the sensing line in the first period, and the deterioration information corresponds to a voltage charged in the sensing line in the second period.
The method of claim 1,
An analog-to-digital converter connected to the sensing line;
A sampling switch disposed between the sensing line and the analog-to-digital converter and selectively connecting the sensing line and the analog-to-digital converter;
A first initialization switch selectively supplying a first initialization voltage to the sensing line; And
A display device including a second initialization switch selectively supplying a second initialization voltage to the sensing line.
The method of claim 6,
The data driver is a display device including the analog to digital converter.
The method of claim 1,
At least one of the plurality of pixels is
A second transistor selectively supplying a data signal to a gate electrode of the first transistor in response to a gate signal;
A third transistor selectively supplying a voltage applied to an electrode connected to the light emitting diode among the electrodes of the first transistor to the sensing line in response to a sensing control signal; And
The display device further comprises a storage capacitor connected between the gate electrode of the first transistor and the source electrode of the first transistor.
The method of claim 8,
The gate signal and the sensing control signal have the same waveform.
The method of claim 8,
The threshold voltage information corresponds to a voltage of the sensing line when the third transistor is turned on in the first period, and the deterioration information is the sensing line when the third transistor is turned off in the second period. A display device corresponding to the voltage of
Among a plurality of pixels receiving a driving voltage corresponding to a data signal, a plurality of data lines electrically connected to the plurality of pixels, a plurality of gate lines electrically connected to the plurality of pixels, and the plurality of pixels And a plurality of sensing lines electrically connected to at least two or more pixels, each of the plurality of pixels including a first transistor supplying a driving current corresponding to the driving voltage and a light emitting diode receiving the driving current Display panel;
A data driver supplying the data signal to the plurality of data lines;
A gate driver supplying gate signals to the plurality of gate lines;
A timing controller controlling the data driver and the gate driver; And
A power control unit for supplying a first power source and a second power having a voltage level lower than that of the first power source,
One frame period is divided into a display period in which a data signal is transmitted to the data line and a sensing period in which the characteristic of the pixel is sensed, and the sensing period includes a first period and a second period, and in the first period The voltage level of the second power source is higher than that of the second power source in the second period.
The method of claim 11,
An analog-to-digital converter connected to the sensing line;
A sampling switch disposed between the sensing line and the analog-to-digital converter and selectively connecting the sensing line and the analog-to-digital converter;
A first initialization switch selectively supplying a first initialization voltage to the sensing line; And
A display device including a second initialization switch selectively supplying a second initialization voltage to the sensing line.
The method of claim 12,
The data driver is a display device including the analog to digital converter.
The method of claim 11,
At least one pixel among the plurality of pixels,
A second transistor selectively supplying a data signal to a gate electrode of the first transistor in response to a gate signal;
A third transistor selectively supplying a voltage applied to an electrode connected to the light emitting diode among the electrodes of the first transistor to the sensing line in response to a sensing control signal; And
The display device further comprises a storage capacitor connected between the gate electrode of the first transistor and the source electrode of the first transistor.
The method of claim 11,
The gate signal and the sensing control signal have the same waveform.
The method of claim 11,
A display device configured to sense a voltage of the sensing line when the third transistor is turned on in the first period, and sense a voltage of the sensing line when the third transistor is turned off in the second period.
The method of claim 11,
A display device in which a voltage level of the sensing line increases in the first period and a voltage level of the sensing line decreases in the second period.
In the driving method of a display device displaying an image using a first transistor generating a driving current and a light emitting diode that emits light by receiving the driving current from the first transistor,
Displaying the image in a display period during one frame period;
Performing at least one of a first period for sensing threshold voltage information on the threshold voltage of the first transistor and a second period for sensing deterioration information on deterioration of the light emitting diode during a sensing period of the one frame period Driving method of a display device comprising a.
The method of claim 18,
The first power source and a second power source having a voltage level lower than that of the first power source is supplied and driven,
A method of driving a display device in which the voltage level of the second power source in the first period is higher than that of the second power source in the second period.

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