Display device

Abstract

A display device includes: a display panel configured to be driven within a frame according to an activation time and a blanking time, the display panel including a plurality of pixels each having a driving transistor; a data driver configured to supply a first data voltage based on image data to the plurality of pixels during the activation time; and a timing controller configured to compensate the image data based on first compensation data for a threshold voltage of the driving transistor and second compensation data for a mobility of the driving transistor, the timing controller including a data compensator, a non-volatile memory, and a plurality of volatile memories. The timing controller may be further configured to read reference first compensation data from the non-volatile memory during the activation time, and update the first compensation data and the second compensation data to be stored in one of the plurality of volatile memories during the blanking time.

Description

[0001] Cross - reference to related applications

[0002] This application claims priority to Korean Patent Application No. 10 - 2021 - 0187193, filed with the Korean Intellectual Property Office on December 24, 2021, and Korean Patent Application No. 10 - 2022 - 0173773, filed with the Korean Intellectual Property Office on December 13, 2022, the disclosures of each application being incorporated herein by reference. Technical Field

[0003] The present disclosure relates to a display device, and more particularly, to a display device capable of more accurately compensating data. Background Art

[0004] Among devices used as displays for computers, televisions, mobile phones, or other electronic devices, there are self - emitting organic light - emitting display devices (OLEDs) and liquid crystal display devices (LCDs) that require a separate light source.

[0005] Among various display devices, an organic light - emitting display device includes a display panel having a plurality of sub - pixels and a driver for driving the display panel. The driver includes a gate driver for providing a gate signal to the display panel and a data driver for providing a data voltage. When signals such as a gate signal and a data voltage are provided to the sub - pixels of the organic light - emitting display device, the selected sub - pixels emit light to display an image.

[0006] In recent years, in order to improve image quality, the mobility and threshold voltage of driving transistors provided in sub - pixels are sensed to compensate data based on the mobility and threshold voltage.

[0007] Due to external factors such as electrostatic discharge (ESD) and shock, the data used for compensation is damaged, and normal compensation driving cannot be performed. Summary of the Invention

[0008] Accordingly, embodiments of the present disclosure relate to a display device that substantially eliminates one or more problems caused by limitations and disadvantages of the related art.

[0009] One object of the present disclosure is to provide a display device that can normally perform compensation even when external factors occur.

[0010] Another object of the present disclosure is to provide a display device that can remove compensated data with errors in real time.

[0011] The features and aspects of the present disclosure are not limited to those mentioned above. Some of the other features and aspects will be given in the following description, and those skilled in the art will clearly understand or learn other parts of these features and aspects according to the following description or by implementing the inventive concept provided herein. The other parts of these features and aspects can be realized and obtained by the structures specifically given or derivable from the specification, claims, and drawings.

[0012] To achieve these and other advantages and in accordance with the purposes of the present disclosure, as specifically and generally described herein, a display device includes: a display panel configured to be driven within a frame in accordance with an activation time and a blanking time, the display panel including a plurality of pixels each having a driving transistor; a data driver configured to provide a first data voltage based on image data to the plurality of pixels during the activation time; and a timing controller configured to compensate the image data based on first compensation data for a threshold voltage of the driving transistor and second compensation data for a mobility of the driving transistor, the timing controller including a data compensator, a non-volatile memory, and a plurality of volatile memories. The timing controller may be further configured to read reference first compensation data from the non-volatile memory during the activation time, the reference first compensation data being a reference value of the first compensation data, and update the first compensation data and the second compensation data during the blanking time to be stored in one of the plurality of volatile memories.

[0013] In another aspect of the present disclosure, a method of driving a display device, the display device including: a display panel configured to be driven within a frame in accordance with an activation time and a blanking time, the display panel including a plurality of pixels each having a driving transistor; a non-volatile memory; a buffer memory, and a plurality of volatile memories, the method including: reading reference first compensation data from the non-volatile memory during the activation time, the reference first compensation data being a reference value of first compensation data for a threshold voltage of the driving transistor, writing the reference first compensation data to the buffer memory during the activation time, reading the reference first compensation data from the buffer memory during the blanking time after the activation time, calculating sensed data for a mobility of the driving transistor during the blanking time, updating the first compensation data based on the reference first compensation data during the blanking time, and updating second compensation data for the mobility of the driving transistor based on the sensed data during the blanking time, and storing the updated first compensation data and the updated second compensation data in one of the plurality of volatile memories during the blanking time.

[0014] In still another aspect of the present disclosure, a display device includes: a display panel configured to be driven within a frame according to an activation time and a blanking time, the display panel including a plurality of pixels each having a driving transistor; a data driver configured to supply a first data voltage based on image data to the plurality of pixels to display an image during the activation time, and to supply a second data voltage for sensing the mobility of the driving transistor to the plurality of pixels to determine a sensing voltage during the blanking time; a plurality of volatile memories storing first compensation data for a threshold voltage of the driving transistor and second compensation data for the mobility of the driving transistor; a non-volatile memory storing reference first compensation data, the reference first compensation data being a reference value of the first compensation data; and a data compensator configured to update the first compensation data based on the reference first compensation data during the blanking time, and to update the second compensation data based on the sensing data during the blanking time.

[0015] According to an exemplary embodiment of the present disclosure, even if there is one or more external factors, it is possible to normally compensate for characteristic values of the driving transistor.

[0016] According to an exemplary embodiment of the present disclosure, the time delay of compensation for image data can be minimized.

[0017] It should be understood that the above general description and the following detailed description of the present disclosure are both exemplary and explanatory, and are intended to provide a further elaboration of the claimed inventive concept. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings included to provide a further understanding of the present disclosure and which are incorporated in and constitute a part of this application illustrate embodiments of the present disclosure and, together with the specification, serve to describe the principles of the present disclosure. In the drawings:

[0019] Figure 1 is a schematic diagram of a display device according to an exemplary embodiment of the present disclosure;

[0020] Figure 2 is a circuit diagram of a sub-pixel of a display device according to an exemplary embodiment of the present disclosure;

[0021] Figure 3 is a block diagram showing a timing controller and a data driver for compensation of a display device according to an exemplary embodiment of the present disclosure;

[0022] Figure 4 is a timing diagram of a signal for sensing the mobility of a display device according to an exemplary embodiment of the present disclosure;

[0023] Figure 5 is a block diagram of a timing controller of a display device according to an exemplary embodiment of the present disclosure;

[0024] Figure 6 A timing diagram for explaining the operation of a timing controller of a display device according to an exemplary embodiment of the present disclosure;

[0025] Figure 7 is a flowchart for explaining the operation of a timing controller of a display device according to an exemplary embodiment of the present disclosure;

[0026] Figure 8 is a diagram for explaining the operation of each frame of a timing controller of a display device according to an exemplary embodiment of the present disclosure;

[0027] Figure 9 is a flowchart for explaining an OnRF (On Real - Time Fast) sensing process of a display device according to an exemplary embodiment of the present disclosure; and

[0028] Figure 10 is a flowchart for explaining an RT (Real - Time) sensing process of a display device according to an exemplary embodiment of the present disclosure. Detailed Description of the Invention

[0029] Embodiments of the present disclosure are described in detail below, and examples of the embodiments are shown in the drawings.

[0030] The transistors for the display device of the present disclosure can be implemented by one or more of n - channel transistors (NMOS) and p - channel transistors (PMOS). The transistors can be implemented by oxide semiconductor transistors having an oxide semiconductor as an active layer or LTPS (Low - Temperature Poly - Silicon) transistors having LTPS as an active layer. The transistors can include at least a gate, a source, and a drain. The transistors can be implemented by thin - film transistors on a display panel. In a transistor, carriers flow from the source to the drain. In the case of an n - channel transistor (NMOS), since the carriers are electrons, in order for electrons to flow from the source to the drain, the source voltage can be lower than the drain voltage. The current direction in the n - channel transistor NMOS is from the drain to the source, and the source can be used as an output terminal. In the case of a p - channel transistor (PMOS), since the carriers are holes, in order for holes to flow from the source to the drain, the source voltage is higher than the drain voltage. In a p - channel transistor (PMOS), holes flow from the source to the drain, causing the current to flow from the source to the drain, and the drain is used as an output terminal. Therefore, the source and the drain can be switched according to the applied voltage, and thus it should be noted that the source and the drain of the transistor are not fixed. In this specification, it is assumed that the transistor is an n - channel transistor (NMOS), but it is not limited thereto, and a p - channel transistor can be used and thus the circuit configuration will be changed.

[0031] The gate signal of the transistor used as a switching element swings between a conduction voltage and a cutoff voltage. The conduction voltage is set to be higher than the threshold voltage Vth of the transistor, and the cutoff voltage is set to be lower than the threshold voltage Vth of the transistor. The transistor conducts in response to the conduction voltage and cuts off in response to the cutoff voltage. In the case of an NMOS, the conduction voltage is a high voltage, and the cutoff voltage is a low voltage. In the case of a PMOS, the conduction voltage can be a low voltage, and the cutoff voltage can be a high voltage.

[0032] Figure 1 is a schematic diagram of a display device according to an exemplary embodiment of the present disclosure.

[0033] As Figure 1 shown, the display device 100 includes a display panel 110, a gate driver 120, a data driver 130, and a timing controller 140.

[0034] The display panel 110 is a panel for displaying an image. The display panel 110 may include various circuits, wirings, and light-emitting diodes provided on a substrate. The display panel 110 is divided by a plurality of data lines DL and a plurality of gate lines GL that cross each other, and includes a plurality of pixels PX connected to the plurality of data lines DL and the plurality of gate lines GL. The display panel 110 includes a display area defined by the plurality of pixels PX and a non-display area in which various signal lines or pads are formed. The display panel 110 may be implemented by a display panel 110 used in various display devices such as a liquid crystal display device, an organic light-emitting display device, or an electrophoretic display device. Hereinafter, the display panel 110 will be described as a panel for an OLED device, but is not limited thereto.

[0035] The timing controller 140 receives timing signals such as a vertical synchronization signal, a horizontal synchronization signal, a data enable signal, or a dot clock through a receiving circuit such as an LVDS or TMDS interface connected to a host system. The timing controller 140 generates a data control signal for controlling the data driver 130 and a gate control signal for controlling the gate driver 130 based on the input timing signals.

[0036] The timing controller 140 processes the image data RGB input from the outside and suitable for the size and resolution of the display panel 110 to provide the processed image data RGB to the data driver 130.

[0037] The timing controller 140 senses the characteristic values (mobility and threshold voltage) of the driving transistors provided in the plurality of pixels PX to generate compensation data for the characteristic values (mobility and threshold voltage) of the driving transistors. The timing controller 140 uses the compensation data to compensate the image data RGB.

[0038] The data driver 130 supplies data voltages Vdata to a plurality of sub-pixels. The data driver 130 includes a source printed circuit board and a plurality of source integrated circuits. Each of the plurality of source driver integrated circuits is supplied with image data RGB and data control signals from the timing controller 140 via the source printed circuit board.

[0039] In response to the data control signal, the data driver 130 converts the image data RGB into gamma voltages to generate data voltages Vdata and supplies the data voltages Vdata via data lines DL of the display panel 110.

[0040] The data driver 130 receives sensing voltages from a plurality of pixels PX to convert the sensing voltages into sensing data for characteristic values (mobility or threshold voltage) of driving transistors. The sensing data is output to the timing controller 140.

[0041] The plurality of source integrated circuits may be connected to the data lines DL of the display panel 100 in the form of chips on film. More specifically, each of the plurality of source integrated circuits may be implemented as a chip disposed on a connection film, and wirings connected to the source integrated circuit chips may be formed on the connection film. However, the arrangement of the plurality of source driver integrated circuits is not limited thereto, and they may also be connected to the data lines DL of the display panel 110 by a chip on glass (COG) process or a tape automated bonding (TAB) process.

[0042] The gate driver 120 supplies gate signals to a plurality of sub-pixels. The gate driver 120 may include a level shifter and a shift register. The level shifter shifts the level of a clock signal input from the timing controller 140 at transistor-transistor-logic (TTL) level and then supplies the clock signal to the shift register. The shift register may be formed in a non-display area of the display panel 110 by a gate-in-panel (GIP) method, but is not limited thereto. The shift register has a plurality of stages that shift the gate signals in response to the clock signal and a driving signal to output them. The plurality of stages included in the shift register sequentially output the gate signals via a plurality of output terminals.

[0043] The display panel 110 may include a plurality of sub-pixels. The plurality of sub-pixels may be sub-pixels that emit different color lights. For example, the plurality of sub-pixels may be red sub-pixels, green sub-pixels, blue sub-pixels, and white sub-pixels, but are not limited thereto. The plurality of sub-pixels may constitute a pixel PX. That is, a red sub-pixel, a green sub-pixel, a blue sub-pixel, and a white sub-pixel constitute one pixel PX, and the display panel 110 may include a plurality of pixels PX.

[0044] Hereinafter, reference will be made to Figure 2 and Figure 1 to describe in more detail the driving circuit for driving one pixel.

[0045] Figure 2 is a circuit diagram of a pixel of a display device according to an exemplary embodiment of the present disclosure.

[0046] Figure 2 Shows a circuit diagram of one pixel among a plurality of pixels of the display device 100.

[0047] As Figure 2 shown, the pixel may include a switching transistor SWT, a sensing transistor SET, a driving transistor DT, a storage capacitor SC, and a light-emitting diode 150.

[0048] The light-emitting diode 150 may include an anode, an organic layer, and a cathode. The organic layer may include various organic layers, such as a hole injection layer, a hole transport layer, an organic light-emitting layer, an electron transport layer, and an electron injection layer. The anode of the light-emitting diode 150 may be connected to the output terminal of the driving transistor DT, and a low potential voltage VSS is applied to the cathode through a low potential voltage line VSSL. Even in Figure 2 it is described that the light-emitting diode 150 is an organic light-emitting diode 150, the present disclosure is not limited thereto; as the light-emitting diode 150, an inorganic light-emitting diode, that is, an LED, may also be used.

[0049] The above-mentioned low potential voltage line VSSL is a positive voltage line for applying a low potential voltage as a positive voltage, and is represented as a ground terminal.

[0050] As Figure 2 shown, the switching transistor SWT is a transistor that transfers a data voltage Vdata to a first node N1 connected to the gate of the driving transistor DT. The switching transistor SWT may include a drain connected to a data line DL, a gate connected to a gate line GL, and a source connected to the gate of the driving transistor DT. The switching transistor SWT is turned on by a scan signal SCAN applied from the gate line GL to transfer the data voltage Vdata provided from the data line DL to the first node N1 connected to the gate of the driving transistor DT.

[0051] As Figure 2 shown, the driving transistor DT is a transistor that provides a driving current to the light-emitting diode 150 to drive the light-emitting diode 150. The driving transistor DT may include a gate corresponding to the first node N1, a source connected to a second node N2 as an output terminal, and a drain connected to a third node N3 as an input terminal. The gate of the driving transistor DT is connected to the switching transistor SWT, the drain is applied with a high potential voltage VDD through a high potential voltage line VDDL, and the source is connected to the anode of the light-emitting diode 150.

[0052] As Figure 2As shown, the storage capacitor SC is a capacitor that maintains a voltage corresponding to the data voltage Vdata for one frame. One electrode of the storage capacitor SC is connected to the first node N1, and the other electrode is connected to the second node N2.

[0053] In the case of the exemplary display device 100, as the driving time of each pixel increases, circuit elements such as the driving transistor DT may deteriorate. Therefore, unique characteristic values of circuit elements such as the driving transistor DT change. Here, the unique characteristic values of the circuit elements may include the threshold voltage Vth of the driving transistor DT or the mobility α of the driving transistor DT. The change in the characteristic values of the circuit elements causes a change in the brightness of the corresponding pixel. Therefore, the change in the characteristic values of the circuit elements can be used to represent the change in the brightness of the pixel.

[0054] In addition, the degree of change in the characteristic values between the circuit elements of each pixel may vary according to the degree of deterioration of each circuit element. This difference in the degree of change in the characteristic values between the circuit elements may cause a brightness deviation between the pixels. Therefore, the characteristic value deviation between the circuit elements can be used to represent the brightness deviation between the pixels. The change in the characteristic values of the circuit elements (i.e., the change in the brightness of the pixel) and the characteristic value deviation between the circuit elements, i.e., the brightness deviation between the pixels, may cause problems such as a reduction in the brightness expressiveness accuracy of the pixel or a screen abnormality.

[0055] Therefore, the pixel of the display device 100 according to an exemplary embodiment of the present disclosure provides a sensing function of sensing the characteristic values of the sensing pixel and a compensation function of compensating the characteristic values of the pixel using the sensing result.

[0056] Therefore, as Figure 2 shown, in addition to the switching transistor SWT, the driving transistor DT, the storage capacitor SC, and the light-emitting diode 150, the pixel may further include a sensing transistor SET to effectively control the voltage state of the source of the driving transistor DT.

[0057] As Figure 2 shown, the sensing transistor SET is connected between the source of the driving transistor DT and the reference voltage line RVL that provides the reference voltage Vref, and the gate is connected to the gate line GL. Therefore, the sensing transistor SET is turned on by the sensing signal SENSE applied through the gate line GL to apply the reference voltage Vref provided through the reference voltage line RVL to the source of the driving transistor DT. In addition, the sensing transistor SET can be used as one of the voltage sensing paths of the source of the driving transistor DT.

[0058] As Figure 2As shown, the switching transistor SWT and the sensing transistor SET of a pixel may share a gate line GL. That is, the switching transistor SWT and the sensing transistor SET are connected to the same gate line GL to receive the same gate signal. However, for ease of explanation, the voltage applied to the gate of the switching transistor SWT is referred to as a scan signal SCAN, and the voltage applied to the gate of the sensing transistor SET is referred to as a sense signal SENSE. However, the scan signal SCAN and the sense signal SENSE applied to one pixel are the same signal transmitted from the same gate line GL.

[0059] However, the present disclosure is not limited thereto. For example, only the switching transistor SWT may be connected to the gate line GL, and the sensing transistor SET may be connected to a separate sensing line. Accordingly, the scan signal SCAN is applied to the switching transistor SWT through the gate line GL, and the sense signal SENSE is applied to the sensing transistor SET through the sensing line.

[0060] Accordingly, a reference voltage Vref is applied to the source of the driving transistor DT through the sensing transistor SET. In addition, a sensing voltage for sensing a threshold voltage Vth of the driving transistor DT or a mobility α of the driving transistor DT is detected through a reference voltage line RVL. In addition, the data driver 120 may compensate for the data voltage Vdata according to a change in the threshold voltage Vth of the driving transistor DT or the mobility α of the driving transistor DT.

[0061] Figure 3 is a block diagram showing a timing controller and a data driver for compensation of a display device according to an exemplary embodiment of the present disclosure.

[0062] As described above, in the display device 100 according to an exemplary embodiment of the present disclosure, a characteristic value or a change in the characteristic value of the driving transistor DT in the pixel PX may be determined according to the sensing voltage of the reference voltage line RVL during a sensing period. Accordingly, the reference voltage line RVL is not only used to transmit the reference voltage Vref, but may also serve as a sensing line for sensing a characteristic value of the driving transistor DT in the pixel PX. Accordingly, the reference voltage line RVL is also referred to as a sensing line.

[0063] Specifically, referring to Figure 2 and Figure 3 , during the sensing period of the display device 100 according to an exemplary embodiment of the present disclosure, a characteristic value or a change in the characteristic value of the driving transistor DT may be reflected as a voltage of a second node N2 of the driving transistor DT (e.g., Vdata-Vth).

[0064] When the sensing transistor SET is turned on, the voltage of the second node N2 of the driving transistor DT can correspond to the sensed voltage of the reference voltage line RVL. In addition, the line capacitance Cline on the reference voltage line RVL can be charged by the voltage of the second node N2 of the driving transistor DT, and the reference voltage line RVL can have a sensed voltage corresponding to the voltage of the second node N2 of the driving transistor DT due to the charged line capacitance Cline.

[0065] The display device 100 according to an exemplary embodiment of the present disclosure controls the on / off of the switching transistor SWT and the sensing transistor SET in the pixel PX, and controls the supply of the data voltage Vdata and the reference voltage Vref, respectively. Accordingly, the second node N2 of the driving transistor DT can be driven to a voltage state reflecting the characteristic value (threshold voltage or mobility) of the driving transistor DT or a change in the characteristic value.

[0066] The data driver 130 of the display device 100 according to an exemplary embodiment of the present disclosure may include an analog-to-digital converter ADC 131 and switching circuits SAM and SPRE. The analog-to-digital converter ADC 131 measures the sensed voltage of the reference voltage line RVL corresponding to the voltage of the second node N2 of the driving transistor DT and converts the sensed voltage into a digital value, while the switching circuits SAM and SPRE sense the characteristic value.

[0067] The data driver 130 may further include a digital-to-analog converter DAC 132 and a switch RPRE for image driving. The digital-to-analog converter DAC 132 is configured to convert the image data RGB into an analog gamma voltage to output the data voltage Vdata. In addition, the data driver 130 may further include a latch circuit and a buffer circuit for processing the image data RGB.

[0068] The ADC 131 and the various switches SAM, SPRE, and RPRE may be provided inside the data driver 130. Alternatively, the ADC 131 and the various switches SAM, SPRE, and RPRE may be provided outside the data driver 130.

[0069] The switching circuits SAM and SPRE for controlling the sensing drive may be a sampling switch SAM and a sensing reference switch SPRE, respectively. The sensing reference switch SPRE controls the connection between each reference voltage line RVL and the sensing reference voltage supply node NpreS to which the reference voltage Vref is supplied, and the sampling switch SAM controls the connection between each reference voltage line RVL and the ADC 131.

[0070] Here, the sensing reference switch SPRE is a switch for controlling the sensing drive, and the reference voltage Vref supplied to the reference voltage line RVL by the sensing reference switch SPRE is the sensing reference voltage VpreS.

[0071] The image driving reference switch RPRE can control the connection between each reference voltage line RVL and the image driving reference voltage supply node Nprer to which the reference voltage Vref is supplied. The image driving reference switch RPRE is a switch for image driving, and the reference voltage Vref supplied to the reference voltage line RVL by the image driving reference switch RPRE is the image driving reference voltage VpreR.

[0072] At this time, the sense reference switch SPRE and the image driving reference switch RPRE can be separately provided or integrated into one body. The sense reference voltage VpreS and the image driving reference voltage VpreR can have the same voltage value or different voltage values.

[0073] The timing controller 140 includes a data compensator 141 configured to generate compensation data CD and a memory 142 for storing data for a long time or a short time.

[0074] The memory 142 stores the sense data SD output from the ADC 131 or the compensation data CD output from the data compensator 141.

[0075] The data compensator 141 calculates new compensation data CD for compensating for changes in characteristic values by comparing the sense data SD and the compensation data CD stored in the memory 142. The new compensation data CD calculated by the data compensator 141 can be stored in the memory 142.

[0076] Specifically, the compensation data CD can be divided into compensation data for the threshold voltage of the driving transistor DT and compensation data for the mobility of the driving transistor DT. For the sake of easy description below, the compensation data for the threshold voltage of the driving transistor DT is called the first compensation data, and the compensation data for the mobility of the driving transistor DT is called the second compensation data.

[0077] Also, the compensation data CD can be in a digital data format. For example, the first compensation data (i.e., the threshold voltage compensation data) can be some bits of the compensation data CD, and the second compensation data (i.e., the mobility compensation data) can be some other bits of the compensation data CD.

[0078] The timing controller 140 uses the compensation data CD stored in the memory 142 to compensate the digital signal type image data RGB to be provided to the data driver 130.

[0079] The compensated image data RGB is output to the data driver 130. Accordingly, the data driver 130 converts the image data RGB compensated by the DAC 132 into a data voltage Vdata of an analog signal type to compensate the data voltage Vdata. After the sensing process for all lines is completed, the compensated data voltage Vdata is output to the corresponding data line DL through the output buffer. As a result, eigenvalue deviations (threshold voltage deviation or mobility deviation) of the driving transistor DT in the corresponding pixel PX can be compensated.

[0080] In addition, the data compensator 141 is not only provided outside the timing controller 140 but also included in the timing controller 140. The memory 142 can be not only located outside the timing controller 140 but also implemented as a register in the timing controller 140.

[0081] Figure 4 is a timing diagram of a signal for sensing the mobility of a display device according to an exemplary embodiment of the present disclosure.

[0082] As Figure 4 shown, the mobility sensing of the driving transistor DT in the display device according to an exemplary embodiment of the present disclosure is performed through an initialization step, a tracking step, and a sampling step. Generally, the mobility of the driving transistor DT is sensed by separately turning on or off the switching transistor SWT and the sensing transistor SET. Accordingly, different from the Figure 2 exemplary structure shown, the sensing operation can be performed using an exemplary structure in which the scan signal SCAN and the sense signal SENSE are respectively applied to the switching transistor SWT and the sensing transistor SET through two separate gate lines GL.

[0083] In the initialization step Initial, through the scan signal SCAN at the conductive level, the switching transistor SWT is turned on and the first node N1 of the driving transistor DT is initialized to the data voltage Vdata for sensing the mobility. Hereinafter, the image driving data voltage generated based on the image data RGB is referred to as the first data voltage, and the sensing data for mobility sensing is referred to as the second data voltage.

[0084] In addition, through the sense signal SENSE at the conductive level, the sensing transistor SET is turned on and the sense reference switch SPRE is turned on. In this state, the second node N2 of the driving transistor DT is initialized to the sense reference voltage VpreS.

[0085] Here, the first data voltage for mobility sensing described above may be different from the first data voltage for displaying an image. Accordingly, after the sensing process is completed during the blanking period, the second data voltage may be restored to the third data voltage.

[0086] The above-mentioned third data voltage may be referred to as an image restoration data voltage. The third data voltage may be the same as the first data voltage, but is not limited thereto. For example, the third data voltage may be a voltage obtained by adjusting the first data voltage based on a compensation voltage.

[0087] The tracking step Tracking is a step of tracking the mobility of the driving transistor DT. The mobility of the driving transistor DT represents the current driving ability of the driving transistor DT, and the voltage of the second node N2 of the driving transistor DT used to calculate the mobility of the driving transistor DT can be tracked by the tracking step.

[0088] In the tracking step, through the scan signal SCAN at the off level, the switching transistor SWT is turned off and the sense reference switch SPRE is switched to the off level. By doing so, both the first node N1 and the second node N2 of the driving transistor DT are floating, so that the voltages of both the first node N1 and the second node N2 of the driving transistor DT rise. Specifically, the voltage of the second node N2 of the driving transistor DT is initialized to the sense reference voltage VpreS and starts to rise from the sense reference voltage VpreS. At this time, the sense transistor SET is turned on, so that the rising voltage of the second node N2 of the driving transistor DT causes the sense voltage of the reference voltage line RVL to rise.

[0089] In the sampling step Sampling, when a predetermined time Δt has elapsed since the time when the voltage of the second node N2 of the driving transistor starts to rise, the sampling switch SAM is turned on. At this time, the ADC 131 senses the sense voltage of the reference voltage line RVL connected through the sampling switch SAM and converts the sense voltage into sense data SD of a digital signal. Here, the sense voltage to be applied to the ADC 131 corresponds to a level (VpreS + ΔV) that is a predetermined voltage ΔV higher than the sense reference voltage VpreS.

[0090] The data compensator 141 identifies the mobility of the driving transistor DT in the corresponding pixel PX based on the sense data SD output from the ADC 131 and compensates for the deviation of the characteristic value (in this case, the mobility) of the driving transistor DT.

[0091] That is, the mobility of the driving transistor DT is proportional to the voltage change (ΔV / Δt) per unit time of the reference voltage line RVL in the tracking step Tracking. In other words, it is proportional to the slope of the voltage waveform of the reference voltage line RVL. At this time, the compensation for the mobility deviation of the driving transistor DT can be referred to as a process of changing the image data RGB. For example, an arithmetic process of multiplying the image data RGB by a second compensation value as mobility compensation data.

[0092] In addition, while driving an image, a sensing process of a driving transistor can be performed in real time. This sensing process is referred to as real-time (RT) sensing process. During the RT sensing process, a sensing process can be performed on pixels PX provided in at least one row during each blanking period.

[0093] Accordingly, after the sensing process is completed for all pixels PX during a plurality of blanking periods, the compensated data voltage Vdata is output to a corresponding data line DL through an output buffer.

[0094] In addition, after the sensing process is performed during the blanking period, for each pixel PX on which the sensing process has been performed, the second data voltage can be restored to the third data voltage. If the data voltage Vdata remains as the second data voltage even after the sensing process, an image related to the image data RGB is output. Accordingly, the data voltage Vdata can be restored to the third data voltage to prevent or reduce a possible degradation in image quality that occurs in pixels on which the sensing process has been completed.

[0095] Furthermore, a process of sensing the mobility of a driving transistor and a process of sensing the threshold voltage of the driving transistor can be distinguished. Specifically, the process of sensing the mobility of the driving transistor DT only requires a shorter time than the process of sensing the threshold voltage, and thus this process can be performed through the RT sensing process performed for a short time. On the contrary, in the process of sensing the threshold voltage of the driving transistor, it takes a long time for the voltage of the second node N2 of the driving transistor DT to saturate, and thus this process cannot be performed through the RT sensing process.

[0096] Accordingly, the sensing data SD obtained from the RT sensing process can be the sensing data SD corresponding to the mobility value of the driving transistor DT. That is, the second compensation data can be consistently updated by using the sensing data SD through the real-time sensing process, but the first compensation data is not updated.

[0097] Here, due to external factors, such as electrostatic discharge (ESD) or physical shock, the compensation data changes. That is, the first compensation data for the threshold voltage becomes an error value due to external factors, and thus the first compensation data remains as the error value. In this case, even if the RT sensing process is performed as described above, the first compensation data remains as the error value, and thus there is a potential problem of generating bright dots or dark dots on the display panel.

[0098] Accordingly, the inventors of the present application recognized that it is also necessary to periodically update the first compensation data.

[0099] Hereinafter, an operation of periodically updating the first compensation data of a memory and a data compensator of a display device according to an exemplary embodiment of the present disclosure will be specifically described.

[0100] Figure 5 It is a block diagram of a timing controller of a display device according to an exemplary embodiment of the present disclosure.

[0101] Reference Figure 5 , the timing controller 140 of the display device according to an exemplary embodiment of the present disclosure further includes a data compensator 141, a non-volatile memory (NAND) 142a, a plurality of volatile memories (DDR1 and DDR2) 142b-1 and 142b-2, and a buffer memory 142c.

[0102] The non-volatile memory (NAND) 142a (hereinafter referred to as NAND) is a long-term storage device that can store data even when the power supply of the display device is interrupted. For example, the NAND 142 can be a NAND flash memory.

[0103] Each of the plurality of volatile memories (DDR1 and DDR2) 142b-1 and 142b-2 is a temporary storage device, and when the power supply of the display device is interrupted, the data is lost. For example, each of the volatile memories can be a double data rate (DDR) DRAM.

[0104] The plurality of volatile memories (DDR1 and DDR2) 142b-1 and 142b-2 may include a first volatile memory (DDR1) 142b-1 (hereinafter referred to as DDR1) and a second volatile memory (DDR2) 142b-2 (hereinafter referred to as DDR2), and the compensation data CD is written into them.

[0105] For a specific frame, the compensation data CD stored in any one of the DDR1 142b-1 and the DDR2 142b-2 can be used to compensate the data voltage Vdata, and the compensation data CD stored in the other of the DDR1 142b-1 and the DDR2 142b-2 can be updated.

[0106] Specifically, during the vertical blanking period (vertical blanking time) of the specific frame, the first compensation data and the second compensation data in the other of the DDR1 142b-1 and the DDR2 142b-2 can be updated.

[0107] The buffer memory 142c is a high-speed temporary storage device for data transfer between the non-volatile memory (NAND) 142a and the plurality of volatile memories (DDR1 and DDR2) 142b-1 and 142b-2.

[0108] The buffer memory 142c can be used to control the read timing of the NAND 142a and the write timing of the DDR1 142b-1 and the DDR2 142b-2. The following will refer to Figure 6 And Figure 7Describe the specific operation of the buffer memory 142c according to an exemplary embodiment of the present disclosure.

[0109] Figure 6 is a timing diagram for explaining the operation of the timing controller of a display device according to an exemplary embodiment of the present disclosure.

[0110] Figure 7 is a flowchart for explaining the operation of the timing controller of a display device according to an exemplary embodiment of the present disclosure.

[0111] Refer to Figures 5 to 7 to describe the RT sensing process according to an exemplary embodiment of the present disclosure for one frame defined by the horizontal synchronization signal Vsync after the display device is powered on.

[0112] As Figure 6 and Figure 7 shown, when the display device is powered on and normally driven (normal drive S110), during the driving period (activation time) of realizing an image, pixels set in a row to be subjected to the RT sensing process can be selected, but the present disclosure is not limited thereto. For example, the RT sensing process can be performed not only on pixels set in one row, but also on pixels set in multiple rows.

[0113] Information about the pixels in a row to be subjected to the RT sensing process is transmitted to the timing controller 140. Accordingly, the timing controller can specify the address of the sensing data SD to be transmitted according to the RT sensing process to be subsequently performed. The timing controller 140 can execute a communication protocol such as, for example, low-voltage differential signaling (LVDS), but is not limited thereto and can execute any of various other communication protocols (RT line selection and RT line address, S120).

[0114] If pixels set in a row to be subjected to the RT sensing process are not selected during the driving period (activation time), the RT sensing process cannot be performed, but normal driving (S110) can be performed to realize an image.

[0115] After pixels set in a row to be subjected to the RT sensing process are selected, during the driving period (activation time), the reference first compensation data Ref CD1 stored in the NAND 142a is read. More specifically, during the driving period (activation time), the buffer memory 142c reads the reference first compensation data Ref CD1 from the NAND 142a (NAND read, S130) and writes the reference first compensation data Ref CD1 into the buffer memory 142c (buffer write, S140).

[0116] The above-mentioned reference first compensation data Ref CD1 refers to the compensation data for the threshold voltage of the driving transistor DT preset before the display device is delivered. As described above, in the case of the threshold voltage sensing process of the driving transistor DT, it takes a considerable amount of time to saturate the voltage of the second node N2 of the driving transistor DT. Therefore, it may not be possible to update the first compensation data using the sensing data SD obtained from the RT sensing process. Thus, the first compensation data, which is the compensation data for the threshold voltage of the driving transistor DT, can be compensated based on the reference first compensation data Ref CD1 stored in the NAND 142a.

[0117] Thus, in the display device according to an exemplary embodiment of the present disclosure, if it enters the vertical blanking period (vertical blanking time) after the driving period (activation time) of S150, the data compensator 141 can read the reference first compensation data Ref CD1 from the buffer memory 142c (buffer reading, S160).

[0118] During the vertical blanking period (vertical blanking time), the data compensator 141 can read the compensation data Previous CD of the previous frame stored in the DDR1 142b-1 (DDR reading). The above-mentioned compensation data Previous CD of the previous frame refers to the compensation data updated in the previous frame before the current frame. That is to say, the compensation data Previous CD of the previous frame can include the first compensation data and the second compensation data updated in that previous frame.

[0119] Meanwhile, during the sensing period of the vertical blanking time, the RT sensing process can be executed to calculate the sensing data SD for the mobility of the driving transistor. That is to say, the data driver 130 can sample the sensing voltage from one electrode of the driving transistor to calculate the sensing data SD for the mobility of the driving transistor (mobility sensing process, S170).

[0120] The data compensator 141 can update the compensation data Previous CD of the previous frame to the compensation data Updated CD of the current frame by using the sensing data SD and the reference first compensation data Ref CD1 (CD update, S180).

[0121] Specifically, the first compensation data of the previous frame can be compared with the reference first compensation data Ref CD1 and updated to the first compensation data of the current frame. That is, if the difference between the first compensation data of the previous frame and the reference first compensation data Ref CD1 is determined to be a predetermined level or higher, the reference first compensation data Ref CD1 can be updated to the first compensation data of the current frame.

[0122] The second compensation data CD2 of the previous frame can be updated to the second compensation data CD2 of the current frame based on the sensed data SD. That is, the data compensator 141 can provide the sensed data SD calculated from the RT sensing process to the second compensation data CD2 of the previous frame read from the DDR1 142b-1 to update it to the second compensation data CD2 of the current frame.

[0123] During the vertical blanking period (vertical blanking time), the data compensator 141 can write the updated compensation data Updated CD to the DDR2 142b-2. That is, the data compensator 141 can write both the updated first compensation data CD1 and the second compensation data CD2 to the DDR2 142b-2 (DDR2 write, S190).

[0124] The data compensator 141 compensates the image data RGB with the compensation data Updated CD updated in the DDR2 142b-2, and converts the compensated image data RGB into a data voltage Vdata of an analog signal type to compensate the data voltage Vdata, thereby performing a normal operation (normal drive, S110).

[0125] That is, in the current frame, the data voltage Vdata can be compensated with the compensation data stored in the DDR2 142b-2 to perform a normal drive. At the same time, in the current frame, the above RT sensing process can be performed again with the compensation data CD stored in the DDR2 142b-2 to update the compensation data CD of the subsequent frame and store the updated compensation data in the DDR1 142b-1.

[0126] In other words, in a specific frame, the compensation data CD stored in either the DDR1 142b-1 or the DDR2 142b-2 can be used to compensate the data voltage Vdata, and the compensation data CD stored in the other of the DDR1 142b-1 and the DDR2 142b-2 can be updated.

[0127] During the driving period (activation time), through the buffer memory 142c, the display device according to an exemplary embodiment of the present disclosure reads the reference first compensation data Ref CD1 stored in the NAND 142a to store the first compensation data CD1 in any one of a plurality of volatile memories such as 142b-1 and 142b-2. The following refers to Figure 8 The operations of a plurality of volatile memories such as 142b-1 and 142b-2 according to an exemplary embodiment of the present disclosure are described in more detail.

[0128] The read reference first compensation data Ref CD1 is stored in the non-volatile memory, so it is not a variable value. Therefore, the first compensation data CD1 updated based on the reference first compensation data Ref CD1 maintains a normal value, enabling the threshold voltage value of the driving transistor to be compensated normally regardless of external factors.

[0129] Hereinafter, an exemplary method for compensating image data and updating compensation data in multiple frames using multiple volatile memories will be described with reference to Figure 8 Description of using multiple volatile memories to compensate image data and update compensation data in multiple frames.

[0130] Figure 8 is a diagram for explaining the operation of each frame of the timing controller of a display device according to an exemplary embodiment of the present disclosure.

[0131] As Figure 8 shown, during the driving period (activation time) of the Nth frame, the reference first compensation data Ref CD1 is read from the NAND 142a (NAND read). During the driving period (activation time) of the Nth frame, the compensation data CD stored in the DDR1 142b-1 is read to compensate the image data RGB. During the blanking period (blanking time) of the Nth frame, the compensation data CD is updated to be written into the DDR2 142b-2 (DDR2 update).

[0132] During the driving period (activation time) of the subsequent (N + 1)th frame, the reference first compensation data Ref CD1 is read from the NAND 142a (NAND read). During the driving period (activation time) of the (N + 1)th frame, the compensation data CD stored in the DDR2 142b-2 is read to compensate the image data RGB. During the blanking period (blanking time) of the (N + 1)th frame, the compensation data CD is updated to be written into the DDR1 142b-1 (DDR1 update).

[0133] As described above, multiple volatile memories 142b-1 and 142b-2 can be alternately used for each frame to perform compensation of image data and update of compensation data in one frame. Therefore, in one frame, not only is the image data compensated, but also the compensation data is updated, so a separate time period for updating the compensation data may not be necessary. As a result, the exemplary display device according to the exemplary embodiment of the present disclosure can compensate the image data without causing a separate time delay.

[0134] Hereinafter, the on-power real-time fast (On RF) mode sensing process will be described with reference to Figure 9 Description of the on-power real-time fast (On RF) mode sensing process. This is a process for compensating the mobility of the driving transistor when the display device is powered on.

[0135] Figure 9It is a flowchart for explaining the On RF sensing process of a display device according to an exemplary embodiment of the present disclosure.

[0136] As Figure 9 shown, before the display device is powered on (energized) and before the display panel realizes an image, parameters for the On RF sensing process are set (parameter setting, S210).

[0137] Specifically, parameter setting refers to the setting of timing information for mobility sensing and information related to the second data voltage, which is the sensing data voltage for mobility sensing.

[0138] To update the second compensation data, which is the compensation data for the mobility of the driving transistor, the sensing data and the second compensation data can be set as reference values (CD2 update ready, S220).

[0139] Next, sensing of the mobility of the driving transistors in the pixels arranged in one row, i.e., one line, is started (1-line sensing start).

[0140] Specifically, referring to Figure 2 and Figure 4 , the switching transistor SWT is turned on by the scan signal SCAN at the conductive level, and the second data voltage (i.e., the sensing data voltage for mobility sensing) is output to the first node N1 of the driving transistor DT (sensing Vdata output, S230).

[0141] Referring to Figure 2 and Figure 4 , the mobility of the driving transistor can be represented by sampling the rising of the sensing voltage on the reference voltage line RVL to calculate the sensing data SD (mobility sensing process, S240).

[0142] Referring to Figure 5 , the calculated sensing data SD represents the mobility value of the driving transistor. Therefore, the data compensator can update the second compensation data CD2 corresponding to the offset of the mobility of the driving transistor by using the sensing data SD (CD2 update, S250).

[0143] Thereafter, the updated second compensation data CD2 can be written into the buffer memory 142c (buffer write, S260).

[0144] After completing the sensing of the mobility of the driving transistors in the pixels arranged in one row, i.e., one line, the second compensation data CD2 written into the buffer memory 142c can be read out (buffer read, S270). The data compensator 141 can then write the updated second compensation data CD2 into the DDR1 142b-1 (DDR1 write, S280).

[0145] As described above, after the mobility of the driving transistors in the pixels arranged in a row (i.e., a line) is sensed, if the sensing of all the pixels has not been performed yet, the mobility of the driving transistors in the pixels arranged in another row (i.e., another line) can be sensed.

[0146] Once the above-described sensing process for all the pixels is performed, the On RF sensing process ends. Thereafter, the display device according to an exemplary embodiment of the present disclosure enters the RT sensing process.

[0147] The following will refer to Figure 10 describe the RT sensing process in more detail. For ease of description, further refer to Figures 4 to 6 .

[0148] Figure 10 is a flowchart for explaining the RF sensing process of a display device according to an exemplary embodiment of the present disclosure.

[0149] After the On RF process is completed, if the display device enters the vertical blanking period (vertical blanking time), the RT sensing process can be prepared to start (RT sensing ready, S310).

[0150] However, if the display device does not enter the vertical blanking period (vertical blanking time), it can enter the mute state (mute). The above mute state refers to a state where no signal is output.

[0151] If the display device enters the driving period (activation time), the first data voltage (i.e., the image driving data voltage) can be output (video Vdata output, S321), and the third data voltage (i.e., the image recovery data voltage) can be prepared (Vdata recovery ready, S322). The buffer memory 142c reads the reference first compensation data Ref CD1 from the NAND 142a (NAND read, S323) and writes the reference first compensation data Ref CD1 into the buffer memory 142c (buffer write, S324).

[0152] Before the first data voltage is output to complete the driving of one frame, the image driving data voltage (i.e., the first data voltage) is continuously output. Once the driving of one frame is completed and the subsequent vertical blanking period (vertical blanking time) is entered, the RT sensing process described above in Figure 4 can be performed to calculate the sensing data SD for the mobility of the driving transistors. That is, the data driver 130 can calculate the sensing data SD for the mobility of the driving transistors by sampling the sensing voltage of one electrode of the driving transistors (mobility sensing process, S330).

[0153] Based on the sensed data SD, the second compensation data CD2 of the previous frame is updated to the second compensation data CD2 of the current frame. That is, the data compensator 141 compares the sensed data SD calculated from the RT sensing process with the second compensation data CD2 of the previous frame read from the DDR1 142b-1 to update the second compensation data CD2 to a new second compensation data CD2 (CD2 update, S340).

[0154] Meanwhile, the data compensator 141 reads the reference first compensation data Ref.CD1 from the buffer memory 142c (buffer read, S351).

[0155] The first compensation data CD1 of the previous frame can be compared with the reference first compensation data Ref.CD1 (CD1 comparison, S352). That is to say, if the difference between the first compensation data CD1 of the previous frame and the reference first compensation data Ref.CD1 is at or above a predetermined error level, the reference first compensation data Ref.CD1 can be updated to the first compensation data CD1 of the previous frame (CD1 update, S353).

[0156] Next, the updated first compensation data CD1 and the updated second compensation data CD2 are written into the buffer memory 142c (buffer write, S361). The first compensation data CD1 and the second compensation data CD2 written into the buffer memory 142c are already ready to be written into the DDR2 142b-2. That is, the data compensator 141 writes the updated first compensation data CD1 and the updated second compensation data CD2 into the DDR2 142b-2 (DDR2 write, S363).

[0157] Meanwhile, after the sensing process at the end of the blanking period, the second data voltage is restored to the third data voltage (Vdata restoration, S370).

[0158] If the compensation data for the pixels in all pixel rows has not been updated completely, the RT sensing process for the pixels in the remaining pixel rows is prepared (RT sensing ready, S310). Then, the above process is repeated for the pixels in the remaining pixel rows.

[0159] On the contrary, if the compensation data CD for the pixels in all pixel rows has been updated, a new RT sensing process is performed on the pixels in all pixel rows using the compensation data written into the DDR2 142b-2.

[0160] That is to say, after performing a new RT sensing process using the compensation data written into the DDR2 142b-2, the updated compensation data CD is written into the DDR1 142b-1. This indicates that multiple volatile memories 142b-1 and 142b-2 can be alternately used for each frame (DDR1<->DDR2; S380).

[0161] By performing the above-described series of processes, the mobility values of the driving transistors are generally corrected using On RF processing. In addition, the mobility values and threshold voltages of the driving transistors are periodically compensated through subsequent RT sensing processing.

[0162] Exemplary embodiments of the present disclosure may also be described as follows:

[0163] A display device according to an exemplary embodiment of the present disclosure may include: a display panel configured to be driven in one frame according to an activation time and a blanking time, the display panel including a plurality of pixels each having a driving transistor; a data driver configured to provide a first data voltage based on image data to the plurality of pixels during the activation time; and a timing controller configured to compensate the image data based on first compensation data for the threshold voltage of the driving transistor and second compensation data for the mobility of the driving transistor, the timing controller including a data compensator, a non-volatile memory, and a plurality of volatile memories. The timing controller may be further configured to read reference first compensation data from the non-volatile memory during the activation time, the reference first compensation data being a reference value of the first compensation data, and update the first compensation data and the second compensation data during the blanking time to be stored in one of the plurality of volatile memories.

[0164] In some exemplary embodiments of the present disclosure, the timing controller may further include a buffer memory configured to read and store the reference first compensation data from the non-volatile memory during the activation time.

[0165] In some exemplary embodiments of the present disclosure, during the blanking time, the data compensator may be configured to read the reference first compensation data from the buffer memory and compare the reference first compensation data and the first compensation data to update the first compensation data.

[0166] In some exemplary embodiments of the present disclosure, during the blanking time, the data driver may be configured to provide a second data voltage for sensing the mobility of the driving transistors to the plurality of pixels and sample the sensing voltage of the electrodes of the driving transistors to calculate sensing data.

[0167] In some exemplary embodiments of the present disclosure, during the blanking time, the data compensator may be configured to update the second compensation data based on the sensing data.

[0168] In some exemplary embodiments of the present disclosure, during the blanking time, the data driver may be further configured to provide a third data voltage for image restoration to the plurality of pixels after calculating the sensing data.

[0169] In some exemplary embodiments of the present disclosure, before the display panel displays an image based on image data, the data driver may be configured to provide a second data voltage for sensing the mobility of the driving transistors to a plurality of pixels, and sample the sensing voltage of the electrodes of the driving transistors to calculate sensing data.

[0170] In some exemplary embodiments of the present disclosure, before the display panel displays an image based on image data, the data compensator may be configured to update second compensation data based on the sensing data.

[0171] In some exemplary embodiments of the present disclosure, the plurality of volatile memories may include a first volatile memory and a second volatile memory. During the blanking time of the Nth frame, the data compensator may be configured to update the first compensation data and the second compensation data to be stored in the second volatile memory, where N is a positive number. During the blanking time of the (N + 1)th frame, the data compensator may be configured to update the first compensation data and the second compensation data to be stored in the first volatile memory.

[0172] In some exemplary embodiments of the present disclosure, during the activation time of the Nth frame, the data compensator may be configured to read the first compensation data and the second compensation data from the first volatile memory to compensate the image data. During the activation time of the (N + 1)th frame, the data compensator may be configured to read the first compensation data and the second compensation data from the second volatile memory to compensate the image data.

[0173] According to an exemplary embodiment of the present disclosure, a method of driving a display device, the display device: including a display panel configured to be driven in an activation time and a blanking time within a frame, the display panel including a plurality of pixels each having a driving transistor; a non-volatile memory; a buffer memory and a plurality of volatile memories, the method including: reading reference first compensation data from the non-volatile memory during the activation time, the reference first compensation data being a reference value of the first compensation data for the threshold voltage of the driving transistor, writing the reference first compensation data into the buffer memory during the activation time, reading the reference first compensation data from the buffer memory during the blanking time after the activation time, calculating sensing data for the mobility of the driving transistor during the blanking time, updating the first compensation data based on the reference first compensation data during the blanking time, and updating second compensation data for the mobility of the driving transistor based on the sensing data during the blanking time, and storing the updated first compensation data and the updated second compensation data in one of the plurality of volatile memories during the blanking time.

[0174] In some exemplary embodiments of the present disclosure, the method may further include: during the activation time, before reading the reference first compensation data, selecting those pixels from the plurality of pixels according to which the sensing data is to be calculated.

[0175] In some exemplary embodiments of the present disclosure, the method may further include providing a first data voltage to a plurality of pixels during an activation time, the first data voltage being an image driving data voltage determined based on first compensation data and second compensation data stored in another one of the plurality of volatile memories.

[0176] In some exemplary embodiments of the present disclosure, calculating sensed data during a blanking time includes providing a second data voltage for sensing the mobility of a driving transistor to the plurality of pixels.

[0177] In some exemplary embodiments of the present disclosure, the method may further include: after calculating the sensed data during the blanking time, providing a third data voltage to the plurality of pixels, the third data voltage being a data voltage for image restoration.

[0178] In some exemplary embodiments of the present disclosure, the method may further include: before the display panel displays an image based on image data, providing a second data voltage for sensing the mobility of a driving transistor to the plurality of pixels to calculate sensed data and update second compensation data based on the sensed data.

[0179] A display device according to an exemplary embodiment of the present disclosure may include: a display panel configured to be driven in accordance with an activation time and a blanking time within a frame, the display panel including a plurality of pixels each having a driving transistor; a data driver configured to provide a first data voltage based on image data to the plurality of pixels to display an image during the activation time, and provide a second data voltage for sensing the mobility of the driving transistor to the plurality of pixels to determine a sensed voltage during the blanking time; a plurality of volatile memories storing first compensation data for a threshold voltage of the driving transistor and second compensation data for the mobility of the driving transistor; a non-volatile memory storing reference first compensation data, the reference first compensation data being a reference value of the first compensation data; and a data compensator configured to update the first compensation data based on the reference first compensation data during the blanking time, and update the second compensation data based on the sensed data during the blanking time.

[0180] In some exemplary embodiments of the present disclosure, the display device may further include a buffer memory configured to read and store the reference first compensation data from the non-volatile memory during the activation time. During the blanking time, the data compensator may be further configured to read the reference first compensation data from the buffer memory and compare the reference first compensation data with the first compensation data to update the first compensation data.

[0181] In some exemplary embodiments of the present disclosure, during the blanking time, the data driver may be further configured to sample a sensed voltage of an electrode of the driving transistor to calculate sensed data, and provide a third data voltage for image restoration to the plurality of pixels after calculating the sensed data.

[0182] In some exemplary embodiments of the present disclosure, a plurality of volatile memories may include a first volatile memory and a second volatile memory. During the blanking time of the Nth frame, the data compensator may be configured to update the first compensation data and the second compensation data for storage in the second volatile memory, where N is a positive number. During the blanking time of the (N + 1)th frame, the data compensator may be configured to update the first compensation data and the second compensation data for storage in the first volatile memory.

[0183] Although the exemplary embodiments of the present disclosure have been described in detail with reference to the accompanying drawings, the present disclosure is not limited thereto and may be implemented in many different forms without departing from the technical concept of the present disclosure. Therefore, it should be understood that the above exemplary embodiments are exemplary in all respects and do not limit the present disclosure. The protection scope of the present disclosure should be interpreted based on the appended claims, and all technical concepts within the equivalent scope should be interpreted as falling within the scope of the present disclosure.

[0184] It will be apparent to those skilled in the art that various modifications and variations can be made to the present disclosure without departing from the technical concept or scope of the present disclosure. Therefore, as long as these modifications and variations of the present disclosure are within the scope of the appended claims and their equivalents, the embodiments of the present disclosure cover these modifications and variations.

Claims

1. A display device, comprising: a display panel configured to be driven in accordance with an activation time and a blanking time within a frame, the display panel including a plurality of pixels each having a driving transistor; a data driver configured to supply a first data voltage based on image data to the plurality of pixels during the activation time; and a timing controller configured to compensate the image data based on first compensation data for a threshold voltage of the driving transistor and second compensation data for a mobility of the driving transistor, the timing controller including a data compensator, a non-volatile memory, and a plurality of volatile memories, wherein the timing controller may be further configured to: read reference first compensation data from the non-volatile memory during the activation time, the reference first compensation data being a reference value of the first compensation data, and update the first compensation data and the second compensation data to be stored in one of the plurality of volatile memories during the blanking time.

2. The display device according to claim 1, wherein the timing controller further includes a buffer memory configured to read and store the reference first compensation data from the non-volatile memory during the activation time.

3. The display device according to claim 2, wherein during the blanking time, the data compensator is configured to read the reference first compensation data from the buffer memory and compare the reference first compensation data with the first compensation data to update the first compensation data.

4. The display device according to claim 1, wherein during the blanking time, the data driver is configured to supply a second data voltage for sensing the mobility of the driving transistor to the plurality of pixels and sample a sensed voltage of an electrode of the driving transistor to calculate sensed data.

5. The display device according to claim 4, wherein during the blanking time, the data compensator is configured to update the second compensation data based on the sensed data.

6. The display device according to claim 4, wherein during the blanking time, the data driver is further configured to supply a third data voltage for image restoration to the plurality of pixels after calculating the sensed data.

7. The display device according to claim 1, wherein before the display panel displays an image based on the image data, the data driver is configured to supply a second data voltage for sensing the mobility of the driving transistor to the plurality of pixels and sample a sensed voltage of an electrode of the driving transistor to calculate sensed data.

8. The display device according to claim 7, wherein before the display panel displays an image based on the image data, the data compensator is configured to update the second compensation data based on the sensed data.

9. The display device according to claim 1, wherein: the plurality of volatile memories include a first volatile memory and a second volatile memory, during the blanking time of the Nth frame, the data compensator is configured to update the first compensation data and the second compensation data to be stored in the second volatile memory, N being a positive number, and during the blanking time of the (N + 1)th frame, the data compensator is configured to update the first compensation data and the second compensation data to be stored in the first volatile memory.

10. The display device according to claim 9, wherein: During the activation time of the Nth frame, the data compensator is configured to read first compensation data and second compensation data from a first volatile memory to compensate for image data, and During the activation time of the (N + 1)th frame, the data compensator is configured to read first compensation data and second compensation data from a second volatile memory to compensate for image data.

11. A method of driving a display device, the display device comprising: A display panel configured to be driven in a frame according to an activation time and a blanking time, the display panel including a plurality of pixels each having a driving transistor; A non-volatile memory; A buffer memory and a plurality of volatile memories, the method including: Reading reference first compensation data from the non-volatile memory during the activation time, the reference first compensation data being a reference value of the first compensation data for the threshold voltage of the driving transistor, Writing the reference first compensation data into the buffer memory during the activation time, Reading the reference first compensation data from the buffer memory during the blanking time after the activation time, Calculating sensed data for the mobility of the driving transistor during the blanking time, Updating the first compensation data based on the reference first compensation data during the blanking time and updating the second compensation data for the mobility of the driving transistor based on the sensed data during the blanking time, and Storing the updated first compensation data and the updated second compensation data in one of the plurality of volatile memories during the blanking time.

12. The method according to claim 11, further including: During the activation time, before reading the reference first compensation data, selecting those pixels among the plurality of pixels for which sensed data is to be calculated.

13. The method according to claim 11, further comprising: Providing a first data voltage to the plurality of pixels during the activation time, the first data voltage being an image driving data voltage determined based on the first compensation data and the second compensation data stored in another one of the plurality of volatile memories.

14. The method according to claim 11, wherein calculating the sensed data during the blanking time includes providing a second data voltage for sensing the mobility of the driving transistor to the plurality of pixels.

15. The method according to claim 14, further including: After calculating the sensed data during the blanking time, providing a third data voltage to the plurality of pixels, the third data voltage being a data voltage for image restoration.

16. The method according to claim 11, further including: Before the display panel displays an image based on the image data, providing a second data voltage for sensing the mobility of the driving transistor to the plurality of pixels to calculate the sensed data and updating the second compensation data based on the sensed data.

Images