Display device and its driving method

Abstract

This disclosure relates to a display device and a driving method thereof. The display device includes: a display panel including sub-pixels; and a driver configured to drive the display panel, wherein the sub-pixels include: a sensing transistor configured to transmit a reference voltage applied via a data line to a second electrode of a capacitor during a first time period included in a horizontal time period; and a switching transistor configured to transmit a data voltage applied via the data line to a first electrode of the capacitor during a second time period included in the same horizontal time period.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit of Korean Patent Application No. 10-2024-0203034, filed on December 31, 2024, which is incorporated herein by reference as if fully set forth herein. Technical Field

[0003] This disclosure relates to display devices and driving methods thereof. Background Technology

[0004] With the advancement of information technology, the market for display devices, which serve as a connection medium between users and information, continues to grow. Consequently, the use of display devices such as light-emitting display devices, quantum dot display (QDD) devices, and liquid crystal display (LCD) devices is increasing.

[0005] The display device described above includes: a display panel including a plurality of sub-pixels; a driver that outputs drive signals for driving the display panel; and a power supply device that generates power to be supplied to the display panel or the driver.

[0006] In such a display device, when drive signals (e.g., scan signals and data signals) are supplied to each of the sub-pixels disposed in the display panel, the selected sub-pixels can transmit light or emit light themselves, and thus an image can be displayed. Summary of the Invention

[0007] This disclosure can improve the aperture ratio based on subpixel binarization and by receiving data voltage and reference voltage through a single data line, thereby extending the lifespan of the display panel and improving display quality. Furthermore, this disclosure can delay transistor degradation characteristics, such that when one of the two transistors is on, the other is off based on opposite voltage conditions, thus contributing to extending the device's lifespan.

[0008] To achieve these and other advantages and for the purposes of this disclosure, as embodied and broadly described herein, a display device includes: a display panel including sub-pixels; and a driver configured to drive the display panel, wherein the sub-pixels include: a sensing transistor configured to transmit a reference voltage applied via a data line to a second electrode of a capacitor during a first time period included in the horizontal time period; and a switching transistor configured to transmit a data voltage applied via the data line to a first electrode of the capacitor during a second time period included in the horizontal time period.

[0009] The sensing transistor may include: a first electrode connected to a data line; a gate electrode connected to a first sensing line included in the first gate line; and a second electrode connected to a second electrode of a capacitor. The switching transistor may include: a first electrode connected to a data line; a gate electrode connected to a first scan line included in the first gate line; and a second electrode connected to the first electrode of a capacitor.

[0010] The sub-pixel may further include: a driving transistor, the driving transistor including: a gate electrode connected to a second electrode of a switching transistor and a first electrode of a capacitor; a first electrode connected to a high-level voltage line; and a second electrode connected to a second electrode of a capacitor and a second electrode of a sensing transistor; and a light-emitting diode, the light-emitting diode including: an anode electrode connected to a second electrode of a sensing transistor, a second electrode of a driving transistor and a second electrode of a capacitor; and a cathode electrode connected to a low-level voltage line.

[0011] The sensing transistor and the switching transistor may have periods during which they perform opposite operations in response to a first gate signal applied through a first gate line.

[0012] The sensing transistor and the switching transistor may have a period during which the sensing transistor and the switching transistor are simultaneously turned off in response to a first gate signal applied through the first gate line.

[0013] Each of the sensing transistor and the switching transistor can be implemented as a CMOS type, including PMOS and NMOS types. The sensing transistor is implemented as one of the PMOS and NMOS types, and the switching transistor is implemented as the other of the PMOS and NMOS types.

[0014] The sensing transistor may include: a first electrode connected to a data line; a gate electrode connected to a first gate line; and a second electrode connected to a second electrode of a capacitor, and the switching transistor may include: a first electrode connected to a data line; a gate electrode connected to a first gate line; and a second electrode connected to a first electrode of a capacitor.

[0015] The sensing transistor can be turned on based on a first gate signal of a second voltage applied through the first gate line, the switching transistor can be turned on based on a first gate signal of a first voltage applied through the first gate line, and the sensing transistor and the switching transistor can be turned off simultaneously based on a first gate signal of a third voltage applied through the first gate line, and the first voltage, the second voltage and the third voltage have different levels.

[0016] In another aspect of this disclosure, a driving method for a display device includes: turning on a sensing transistor to transfer a reference voltage applied via a data line to a second electrode of a capacitor during a first time period included in a horizontal time period; turning on a switching transistor to transfer a data voltage applied via the data line to a first electrode of the capacitor during a second time period included in the horizontal time period; and driving a driving transistor based on the voltage difference between the data voltage stored in the capacitor and the reference voltage, and enabling a light-emitting diode to emit light based on a driving current generated from the driving transistor.

[0017] The sensing transistor may include: a first electrode connected to a data line; a gate electrode connected to a first sensing line included in the first gate line; and a second electrode connected to a second electrode of a capacitor. The switching transistor may include: a first electrode connected to a data line; a gate electrode connected to a first scan line included in the first gate line; and a second electrode connected to the first electrode of a capacitor.

[0018] The sensing transistor may include: a first electrode connected to a data line; a gate electrode connected to a first gate line; and a second electrode connected to a second electrode of a capacitor, and the switching transistor may include: a first electrode connected to a data line; a gate electrode connected to a first gate line; and a second electrode connected to a first electrode of a capacitor.

[0019] The sensing transistor can be turned on based on a first gate signal of a second voltage applied through the first gate line, the switching transistor can be turned on based on a first gate signal of a first voltage applied through the first gate line, and the sensing transistor and the switching transistor can be turned off simultaneously based on a first gate signal of a third voltage applied through the first gate line, and the first voltage, the second voltage and the third voltage have different levels.

[0020] The driving transistor may include: a gate electrode connected to the second electrode of the switching transistor and the first electrode of the capacitor; a first electrode connected to a high-level voltage line; and a second electrode connected to the second electrode of the capacitor and the second electrode of the sensing transistor; and the light-emitting diode may include: an anode electrode connected to the second electrode of the sensing transistor, the second electrode of the driving transistor and the second electrode of the capacitor; and a cathode electrode connected to a low-level voltage line.

[0021] This disclosure can improve the aperture ratio based on subpixel binarization and by receiving data voltage and reference voltage through a single data line, thereby extending the lifespan of the display panel and improving display quality. Furthermore, this disclosure can delay transistor degradation characteristics, such that when one of the two transistors is on, the other is off based on opposite voltage conditions, thus contributing to extending the device's lifespan. Attached Figure Description

[0022] The accompanying drawings are included to provide a further understanding of this disclosure and are incorporated in and constitute a part of this application. The drawings illustrate embodiments of the disclosure and, together with the specification, serve to explain the principles of the disclosure. In the drawings:

[0023] Figure 1 It is a schematic block diagram illustrating a light-emitting display device, and Figure 2 and Figure 3 This is a diagram used to describe the configuration of a gate driver of the in-panel gate (GIP) type;

[0024] Figure 4 This is a diagram illustrating some of the elements in the light-emitting display device according to the first embodiment, and Figure 5 This is a diagram illustrating the circuit configuration of the sub-pixels according to the first embodiment;

[0025] Figure 6 This is a diagram illustrating the circuit configuration of each of the first and second sub-pixels according to the first embodiment. Figure 7 This illustrates the first embodiment. Figure 6 The diagram shows the driving waveforms of each of the first and second sub-pixels, and... Figure 8 and Figure 9 It shows based on Figure 7 A diagram showing the operational state of the first sub-pixel of the driving waveform;

[0026] Figure 10 This is a diagram illustrating some of the elements in the light-emitting display device according to the second embodiment, and Figure 11 This is a diagram illustrating the circuit configuration of the sub-pixels according to the second embodiment;

[0027] Figure 12 This is a diagram illustrating the circuit configuration of each of the first and second sub-pixels according to the second embodiment. Figure 13 This illustrates the second embodiment. Figure 12 The diagram shows the driving waveforms of each of the first and second sub-pixels, and... Figure 14 and Figure 15 It shows based on Figure 13 A diagram showing the operational state of the first sub-pixel of the driving waveform;

[0028] Figure 16 It is a diagram used to describe the characteristics of the transistor according to the second embodiment; and

[0029] Figure 17 and Figure 18 This is a diagram used to describe an example of a modification of a sub-pixel according to the third embodiment. Detailed Implementation

[0030] In the following description, the present disclosure will be described more fully with reference to the accompanying drawings, which illustrate exemplary embodiments of the present disclosure. However, the present disclosure may be implemented in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present disclosure will be thorough and complete and will fully convey the concept of the present disclosure to those skilled in the art.

[0031] The display device according to this disclosure can be applied to televisions (TVs), video players, personal computers (PCs), home theaters, vehicle electronics, and smartphones, but is not limited thereto. The display device according to this disclosure can be implemented as a light-emitting display device, a quantum dot display (QDD) device, or a liquid crystal display (LCD) device. Hereinafter, for ease of description, a self-emissive light-emitting display device using inorganic or organic light-emitting diodes will be described, for example.

[0032] Furthermore, the transistors described below can be implemented using n-type transistors, p-type transistors, or a combination of n-type and p-type transistors. A transistor can be a three-electrode device comprising a gate, a source, and a drain. The source can be the electrode that provides charge carriers to the transistor. In a transistor, charge carriers can flow from the source. The drain can be the electrode from which charge carriers flow from the transistor to the outside. That is, in a transistor, charge carriers flow from the source to the drain.

[0033] In a p-type transistor, since the charge carriers are holes, the source voltage can be higher than the drain voltage, allowing holes to flow from the source to the drain. Because holes flow from the source to the drain, current can flow from the source to the drain in a p-type transistor. Conversely, in an n-type transistor, since the charge carriers are electrons, the source voltage can be lower than the drain voltage, allowing electrons to flow from the source to the drain. Because electrons flow from the source to the drain, current can flow from the drain to the source in an n-type transistor. However, the source and drain of a transistor can switch between each other based on the voltage applied to them. Therefore, in the following description, one of the source and drain will be described as the first electrode, and the other as the second electrode.

[0034] Figure 1 It is a schematic block diagram showing a light-emitting display device, and Figure 2 and Figure 3 This is a diagram used to describe the configuration of a gate driver of the in-panel gate (GIP) type.

[0035] like Figures 1 to 3As shown, the light-emitting display device according to the embodiments of the present disclosure may include a timing controller (timing control circuit) 120, a gate driver (gate drive circuit) 130, a data driver (data drive circuit) 140, a display panel 150, and a power supply device (power supply circuit) 180.

[0036] The video supply unit 110 (a complete system or a host system) can output video data signals supplied from an external source or image data signals stored in its internal memory. The video supply unit 110 can supply data signals and various drive signals to the timing controller 120.

[0037] The timing controller 120 can output a gate timing control signal GDC for controlling the operating timing of the gate driver 130, a data timing control signal DDC for controlling the operating timing of the data driver 140, and various synchronization signals (vertical synchronization signal Vsync and horizontal synchronization signal Hsync). The timing controller 120 can provide the data driver 140 with the data signal DATA and the data timing control signal DDC supplied from the video supply unit 110. The timing controller 120 can be implemented as an integrated circuit (IC) and can be mounted on a printed circuit board (PCB), but is not limited thereto.

[0038] Gate driver 130 can output a gate signal (or gate voltage) in response to a gate timing control signal GDC supplied from timing controller 120. Gate driver 130 can supply gate signals to multiple sub-pixels included in display panel 150 through multiple gate lines GL1 to GLm. Gate driver 130 can be implemented as an IC type, or it can be directly disposed on display panel 150 as a GIP type, but is not limited thereto. In the following description, for ease of description, as Figure 2 and Figure 3 As shown, a gate driver of type GIP will be described, for example.

[0039] The gate driver 130 may include a plurality of shift registers 130a and 130b, which are disposed on one side and the other side of the non-display area NA of the display panel 150 as GIP type. Based on the GIP type, the shift registers 130a and 130b may be configured as thin-film type in the non-display area NA of the display panel 150. The gate driver 130 may output gate signals Gate[1] to Gate[m] to turn on or off transistors formed in the display area AA of the display panel 150.

[0040] Gate driver 130 can operate based on signals and voltages output from timing controller 120, power supply 180, and level shifter 160. Level shifter 160 can generate gate control signals required to drive gate drivers 130, 130a, and 130b based on signals and voltages output from timing controller 120 and power supply 180.

[0041] In response to the data timing control signal DDC supplied from the timing controller 120, the data driver 140 can sample and latch the data signal DATA, convert the digital data signal into an analog data voltage based on the gamma reference voltage, and output the analog data voltage. The data driver 140 can supply data voltages to the sub-pixels of the display panel 150 through multiple data lines DL1 to DLn, respectively. The data driver 140 can be implemented as an IC type, or it can be mounted on the display panel 150 or a PCB, but is not limited thereto.

[0042] The power supply device 180 can generate high-level voltages and low-level voltages based on an externally supplied input voltage, and can output high-level voltages and low-level voltages through the high-level voltage line EVDD and the low-level voltage line EVSS. In addition to high-level voltages and low-level voltages, the power supply device 180 can also generate and output voltages required to drive the gate driver 130 or the data driver 140.

[0043] Display panel 150 can be manufactured based on a rigid or flexible substrate, such as glass, silicone, or polyimide. Display panel 150 may include a plurality of subpixels SP for displaying images. Subpixels SP may be self-emissive, facing an upper substrate, a lower substrate, or both of the upper and lower substrates of display panel 150. Subpixels SP may emit light of one color selected from red, green, blue, and white. Display panel 150 can display images based on pixels configured with red, green, and blue subpixels, or pixels configured with red, green, blue, and white subpixels.

[0044] In the above description, each of the timing controller 120, gate driver 130, and data driver 140 has been described as a separate element. However, depending on the implementation type of the light-emitting display device, one or more of the timing controller 120, gate driver 130, and data driver 140 may be integrated into a single IC.

[0045] Figure 4 This is a diagram illustrating some of the elements in the light-emitting display device according to the first embodiment, and Figure 5 This is a diagram illustrating the circuit configuration of a sub-pixel according to the first embodiment.

[0046] like Figure 4 As shown, according to the first embodiment, the sub-pixel SP can be defined by a first gate line GL1 including a first scan line SL1 and a first sensing line SS1, a high-level voltage line EVDD, a low-level voltage line EVSS, and a first data line DL1.

[0047] According to the first embodiment, the data driver 140 may include a voltage output circuit 141, a pixel sensing circuit 145, and a selection switch SEL. The voltage output circuit 141 outputs a data voltage to be applied to the sub-pixel SP through the first data line DL1, and the pixel sensing circuit 145 senses the elements included in the sub-pixel SP through the first data line DL1.

[0048] The data driver 140 can control the selection switch SEL during a normal display driving period, so that the first data line DL1 is electrically connected to the voltage output circuit 141, and can then output the data voltage for driving the sub-pixel SP.

[0049] The data driver 140 can control the selection switch SEL during a separately defined sensing drive period, such that the first data line DL1 is electrically connected to the pixel sensing circuit 145, and can then sense the elements included in the sub-pixel SP to obtain a sensed value. In this case, the sensed value can be obtained as a current value or a voltage value.

[0050] The data driver 140 can be combined with the timing controller 120 to transmit sensed values ​​sensed during a sense drive period to the timing controller 120. The timing controller 120 can compensate and output a data signal based on the sensed values ​​transmitted from the data driver 140. For this purpose, the timing controller 120 may also include a degradation determiner 128 and a degradation compensator 129.

[0051] The degradation determiner 128 can determine whether the driving transistor or light-emitting diode is degraded based on the sensed value, and when degradation occurs, the degradation determiner 128 can output a degradation value. The degradation compensator 129 can calculate a compensation value based on the degradation value output from the degradation determiner 128, and can reflect the data signal to be supplied to the data driver 140.

[0052] like Figure 5 As shown, the sub-pixel SP1 according to the first embodiment may include a switching transistor SW, a sensing transistor ST, a driving transistor DR, a capacitor CST, and a light-emitting diode OLED.

[0053] The switching transistor SW may include: a gate electrode connected to a first scan line SL1 included in the first gate line GL1; a first electrode connected to a first data line DL1; and a second electrode connected to the gate electrode of the driving transistor DR and the first electrode of the capacitor CST. The switching transistor SW may be turned on based on a first scan signal applied through the first scan line SL1, and may deliver the data voltage applied through the first data line DL1 to the first electrode of the capacitor CST.

[0054] The sensing transistor ST may include: a gate electrode connected to a first sensing line SS1 included in the first gate line GL1; a first electrode connected to a first data line DL1; and a second electrode connected to a second electrode of a driving transistor DR, a second electrode of a capacitor CST, and an anode electrode of a light-emitting diode OLED. The sensing transistor ST may be turned on based on a first sensing signal applied through the first sensing line SS1, and may transmit a reference voltage applied through the first data line DL1 to a sensing node connected to the second electrode of the driving transistor DR, the second electrode of the capacitor CST, and the anode electrode of the light-emitting diode OLED. During a separately defined sensing drive period, the sensing transistor ST may be turned on to sense the threshold voltage of the driving transistor DR or the threshold voltage of the light-emitting diode OLED through the sensing node.

[0055] The driving transistor DR may include: a gate electrode connected to the second electrode of the switching transistor SW and the first electrode of the capacitor CST; a first electrode connected to the high-level voltage line EVDD; and a second electrode connected to the second electrode of the capacitor CST, the second electrode of the sensing transistor ST, and the anode electrode of the light-emitting diode OLED. The driving transistor DR can be turned on based on the data voltage stored in the capacitor CST and can generate a driving current.

[0056] The capacitor CST may include: a first electrode connected to the second electrode of the switching transistor SW and the gate electrode of the driving transistor DR; and a second electrode connected to the second electrode of the driving transistor DR, the second electrode of the sensing transistor ST, and the anode electrode of the light-emitting diode OLED. The capacitor CST can apply the data voltage stored therein to the gate electrode of the driving transistor DR.

[0057] An OLED may include: an anode electrode connected to a second electrode of a capacitor CST, a second electrode of a sensing transistor ST, and a second electrode of a driving transistor DR; and a cathode electrode connected to a low-level voltage line EVSS. An OLED can emit light based on a driving current generated from the driving transistor DR.

[0058] Figure 6This is a diagram illustrating the circuit configuration of each of the first and second sub-pixels according to the first embodiment. Figure 7 This illustrates the first embodiment. Figure 6 The diagram shows the driving waveforms of each of the first and second sub-pixels, and... Figure 8 and Figure 9 It shows based on Figure 7 The diagram shows the operational state of the first sub-pixel of the driving waveform.

[0059] like Figure 6 As shown, the first sub-pixel SP1 and the second sub-pixel SP2 can be respectively disposed in the upper and lower portions of the display panel in the vertical direction. The first sub-pixel SP1 can be defined by the first gate line GL1, the first data line DL1, the high-level voltage line EVDD, and the low-level voltage line EVSS. The second sub-pixel SP2 can be defined by the second gate line GL2, the first data line DL1, the high-level voltage line EVDD, and the low-level voltage line EVSS.

[0060] The first sub-pixel SP1 may include a first switching transistor SW1, a first sensing transistor ST1, a first driving transistor DR1, a first capacitor CST1, and a first light-emitting diode OLED1. The second sub-pixel SP2 may include a second switching transistor SW2, a second sensing transistor ST2, a second driving transistor DR2, a second capacitor CST2, and a second light-emitting diode OLED2.

[0061] Based on the first gate line GL1 and the second gate line GL2, the first sub-pixel SP1 and the second sub-pixel SP2 can be arranged vertically in the display panel, and therefore can have the same configuration and the same connection relationship, and can operate at different times. This will be described below.

[0062] like Figure 4 , Figure 7 and Figure 8 As shown, the first sensing transistor ST1 of the first sub-pixel SP1 can be turned on within a first time period based on a high-voltage first sensing signal Sen1. The first time period can be, but is not limited to, half of a horizontal time 1H. The selection switch SEL of the data driver 140 can connect the first data line DL1 to the voltage output circuit 141 within the first time period during which the first sensing transistor ST1 is turned on.

[0063] The data driver 140 can drive the voltage output circuit 141 during the first moment when the first sensing transistor ST1 is turned on, so that a reference voltage Ref is output through the first data line DL1. The reference voltage Ref can be applied through the first data line DL1 and can be transmitted to the second electrode of the first capacitor CST1 via the turned-on first sensing transistor ST1.

[0064] like Figure 4 , Figure 7 and Figure 9 As shown, the first switching transistor SW1 of the first sub-pixel SP1 can be turned on during a second time period based on a high-voltage first scan signal Scn1. This second time period can correspond to the other half of a horizontal time 1H, but is not limited to this. The selection switch SEL of the data driver 140 can connect the first data line DL1 to the voltage output circuit 141 during the second time that the first switching transistor SW1 is turned on.

[0065] The data driver 140 can drive the voltage output circuit 141 during the second time the first switching transistor SW1 is turned on, so that a first data voltage Data1 is output through the first data line DL1. The first data voltage Data1 can be applied through the first data line DL1 and can be transmitted to the first electrode of the first capacitor CST1 via the turned-on first switching transistor SW1.

[0066] When the high-voltage first scan signal Scn1 changes to a low-voltage first scan signal Scn1 within the third time period, the first driving transistor DR1 of the first sub-pixel SP1 can generate a first driving current, and the first light-emitting diode OLED1 of the first sub-pixel SP1 can emit light based on the first driving current. At this time, the first driving transistor DR1 of the first sub-pixel SP1 can generate the first driving current based on the voltage difference between the reference voltage Ref transmitted through the second electrode of the first capacitor CST1 and the first data voltage Data1 transmitted through the first electrode of the first capacitor CST1.

[0067] Furthermore, the second sub-pixel SP2, which is set in the next row relative to the first sub-pixel SP1, can be operated based on the same method as the first sub-pixel SP1, which will be briefly described below.

[0068] When the high-voltage first scan signal Scn1 changes to a low-voltage first scan signal Scn1, a high-voltage second sensing signal Sen2 can be generated. When the high-voltage second sensing signal Sen2 is generated, a reference voltage Ref can be supplied to the second sub-pixel SP2.

[0069] Subsequently, when the high-voltage second sensing signal Sen2 changes to a low-voltage second sensing signal Sen2, a high-voltage second scan signal Scn2 can be generated. When the high-voltage second scan signal Scn2 is generated, a second data voltage Data2 can be supplied to the second sub-pixel SP2.

[0070] Subsequently, when the high-voltage second scan signal Scn2 changes to the low-voltage second scan signal Scn2, the second driving transistor DR2 of the second sub-pixel SP2 can generate a second driving current, and the second light-emitting diode OLED2 of the second sub-pixel SP2 can emit light based on the second driving current.

[0071] Figure 10 This is a diagram illustrating some of the elements in the light-emitting display device according to the second embodiment, and Figure 11 This is a diagram illustrating the circuit configuration of a sub-pixel according to the second embodiment.

[0072] like Figure 10 As shown, the sub-pixel SP according to the second embodiment can be defined by a first gate line GL1, a high-level voltage line EVDD, a low-level voltage line EVSS, and a first data line DL1. Except that the first gate line GL1 does not include multiple signal lines, the sub-pixel SP according to the second embodiment can be the same as the sub-pixel according to the first embodiment. Furthermore, the data driver 140 according to the second embodiment can be the same as the data driver according to the first embodiment. Therefore, the related description can be referred to the first embodiment.

[0073] like Figure 11 As shown, the sub-pixel SP1 according to the second embodiment may include a switching transistor SW, a sensing transistor ST, a driving transistor DR, a capacitor CST, and a light-emitting diode OLED. In the following, in the second embodiment, an example will be described where the switching transistor SW, implemented as n-type, and the sensing transistor ST, implemented as p-type, are configured as CMOS (Complementary Metal-Oxide-Semiconductor) type. However, this may only be one embodiment; instead, the switching transistor SW may be implemented as p-type, and the sensing transistor ST as n-type.

[0074] The switching transistor SW may include: a gate electrode connected to a first gate line GL1; a first electrode connected to a first data line DL1; and a second electrode connected to the gate electrode of the driving transistor DR and the first electrode of the capacitor CST. The switching transistor SW may be turned on based on a first gate signal with a first voltage applied through the first gate line GL1, and may transmit the data voltage applied through the first data line DL1 to the first electrode of the capacitor CST.

[0075] The sensing transistor ST may include: a gate electrode connected to a first gate line GL1; a first electrode connected to a first data line DL1; and a second electrode connected to a second electrode of a driving transistor DR, a second electrode of a capacitor CST, and an anode electrode of a light-emitting diode OLED. The sensing transistor ST may be turned on based on a first gate signal of a second voltage applied through the first gate line GL1, and may transmit a reference voltage applied through the first data line DL1 to a sensing node connected to the second electrode of the driving transistor DR, the second electrode of the capacitor CST, and the anode electrode of the light-emitting diode OLED. During a separately defined sensing drive period, the sensing transistor ST may be turned on to sense the threshold voltage of the driving transistor DR or the threshold voltage of the light-emitting diode OLED through the sensing node.

[0076] The driving transistor DR may include: a gate electrode connected to the second electrode of the switching transistor SW and the first electrode of the capacitor CST; a first electrode connected to the high-level voltage line EVDD; and a second electrode connected to the second electrode of the capacitor CST, the second electrode of the sensing transistor ST, and the anode electrode of the light-emitting diode OLED. The driving transistor DR can be turned on based on the data voltage stored in the capacitor CST and can generate a driving current.

[0077] The capacitor CST may include: a first electrode connected to the second electrode of the switching transistor SW and the gate electrode of the driving transistor DR; and a second electrode connected to the second electrode of the driving transistor DR, the second electrode of the sensing transistor ST, and the anode electrode of the light-emitting diode OLED. The capacitor CST can apply the data voltage stored therein to the gate electrode of the driving transistor DR.

[0078] An OLED may include: an anode electrode connected to a second electrode of a capacitor CST, a second electrode of a sensing transistor ST, and a second electrode of a driving transistor DR; and a cathode electrode connected to a low-level voltage line EVSS. An OLED can emit light based on a driving current generated from the driving transistor DR.

[0079] Figure 12 This is a diagram illustrating the circuit configuration of each of the first and second sub-pixels according to the second embodiment. Figure 13 This illustrates the second embodiment. Figure 12 The diagram shows the driving waveforms of each of the first and second sub-pixels, and... Figure 14 and Figure 15 It shows based on Figure 13 The diagram shows the operational state of the first sub-pixel of the driving waveform.

[0080] like Figure 12As shown, the first sub-pixel SP1 and the second sub-pixel SP2 can be respectively disposed in the upper and lower portions of the display panel in the vertical direction. The first sub-pixel SP1 can be defined by the first gate line GL1, the first data line DL1, the high-level voltage line EVDD, and the low-level voltage line EVSS. The second sub-pixel SP2 can be defined by the second gate line GL2, the first data line DL1, the high-level voltage line EVDD, and the low-level voltage line EVSS.

[0081] The first sub-pixel SP1 may include a first switching transistor SW1, a first sensing transistor ST1, a first driving transistor DR1, a first capacitor CST1, and a first light-emitting diode OLED1. The second sub-pixel SP2 may include a second switching transistor SW2, a second sensing transistor ST2, a second driving transistor DR2, a second capacitor CST2, and a second light-emitting diode OLED2.

[0082] Based on the first gate line GL1 and the second gate line GL2, the first sub-pixel SP1 and the second sub-pixel SP2 can be arranged vertically in the display panel, and therefore can have the same configuration and the same connection relationship, and can operate at different times. This will be described below.

[0083] like Figure 10 , Figure 13 and Figure 14 As shown, the first sensing transistor ST1 of the first sub-pixel SP1 can be turned on within a first time period based on the first gate signal Gate1 of the second voltage (-V, which is a negative voltage). The first time period can be, but is not limited to, half of a horizontal time 1H. The selection switch SEL of the data driver 140 can connect the first data line DL1 to the voltage output circuit 141 within the first time period during which the first sensing transistor ST1 is turned on.

[0084] The data driver 140 can drive the voltage output circuit 141 during the first moment when the first sensing transistor ST1 is turned on, so that a reference voltage Ref is output through the first data line DL1. The reference voltage Ref can be applied through the first data line DL1 and can be transmitted to the second electrode of the first capacitor CST1 via the turned-on first sensing transistor ST1.

[0085] like Figure 10 , Figure 13 and Figure 15As shown, the first switching transistor SW1 of the first sub-pixel SP1 can be turned on during a second time period based on the first gate signal Gate1 of the first voltage (+V, which is a positive voltage). The second time period can be the time corresponding to the other half of a horizontal time 1H, but is not limited to this. The selection switch SEL of the data driver 140 can connect the first data line DL1 to the voltage output circuit 141 during the second time during which the first switching transistor SW1 is turned on.

[0086] The data driver 140 can drive the voltage output circuit 141 during the second time the first switching transistor SW1 is turned on, so that a first data voltage Data1 is output through the first data line DL1. The first data voltage Data1 can be applied through the first data line DL1 and can be transmitted to the first electrode of the first capacitor CST1 via the turned-on first switching transistor SW1.

[0087] When the first gate signal Gate1 with a first voltage (+V, which is a positive voltage) changes to the first gate signal Gate1 with a third voltage (0V, which is a ground voltage) within a third time period, the first driving transistor DR1 of the first sub-pixel SP1 can generate a first driving current, and the first light-emitting diode OLED1 of the first sub-pixel SP1 can emit light based on the first driving current. At this time, the first driving transistor DR1 of the first sub-pixel SP1 can generate the first driving current based on the voltage difference between the reference voltage Ref transmitted through the second electrode of the first capacitor CST1 and the first data voltage Data1 transmitted through the first electrode of the first capacitor CST1.

[0088] Furthermore, the second sub-pixel SP2, located next to the first sub-pixel SP1, can be operated using the same method as the first sub-pixel SP1, which will be briefly described below.

[0089] When the first gate signal Gate1, with a first voltage (+V, which is a positive voltage), changes to a third voltage (0V, which is a ground voltage), a second gate signal Gate2, with a second voltage (-V, which is a negative voltage), can be generated. When the second gate signal Gate2 with the second voltage is generated, a reference voltage Ref can be supplied to the second sub-pixel SP2.

[0090] Subsequently, when the second gate signal Gate2 of the second voltage becomes the second gate signal Gate2 of the first voltage (+V, which is a positive voltage), the second data voltage Data2 can be supplied to the second sub-pixel SP2.

[0091] Subsequently, when the second gate signal Gate2 of the first voltage becomes the second gate signal Gate2 of the third voltage (0 V, which is the ground voltage), the second driving transistor DR2 of the second sub-pixel SP2 can generate the second driving current, and the second light-emitting diode OLED2 of the second sub-pixel SP2 can emit light based on the second driving current.

[0092] Furthermore, the advantages of implementing the first sensing transistor ST1 and the first switching transistor SW1 as CMOS types will be described below.

[0093] Figure 16 This is a diagram used to describe the characteristics of the transistor according to the second embodiment.

[0094] like Figure 16 As shown, according to the second embodiment, the sensing transistor can be implemented as a PMOS (P-channel MOS) type, and the switching transistor can be implemented as an NMOS (N-channel MOS) type. That is, the sensing transistor and the switching transistor can be implemented as CMOS type. In this case, CMOS can be implemented as oxide semiconductor and low-temperature polycrystalline silicon (LTPS) semiconductor, but is not limited to these.

[0095] According to the second embodiment, the layer configuring the oxide semiconductor can be different from the layer configuring the LTPS semiconductor. Therefore, in the thin-film process included in the manufacturing process of the display panel, the threshold voltage (based on the Vth offset of the process control) can be controlled such that the NMOS transistor is turned on based on a first voltage (+V) (NMOS turned on), the PMOS transistor is turned on based on a second voltage (-V) (PMOS turned on), and the NMOS transistor and the PMOS transistor are simultaneously turned off based on a third voltage (0V) (NMOS turned off, PMOS turned off).

[0096] Based on the above voltage conditions, the transistor implemented as a CMOS transistor can perform different operations, and the levels of the first voltage (+V), the second voltage (-V), and the third voltage (0V) can be offset in the process control operation.

[0097] Furthermore, according to the second embodiment, when one of the NMOS transistor and the PMOS transistor is turned on, the other transistor can be turned off based on the opposite voltage conditions, and thus the degradation characteristics of the transistor operating as a switch type can be delayed, thereby helping to improve the lifespan of the device.

[0098] Figure 17 and Figure 18 This is a diagram used to describe an example of a modification of a sub-pixel according to the third embodiment.

[0099] like Figure 17As shown, the sub-pixel SP1 according to the third embodiment can be configured as in the first embodiment, but there may be differences, namely, the sub-pixel SP1 includes the pixel circuit DRC. Furthermore, as... Figure 18 As shown, the sub-pixel SP1 according to the third embodiment can be configured as the second embodiment, but there may be differences, namely, the sub-pixel SP1 includes the pixel circuit DRC.

[0100] According to a third embodiment, the pixel circuit DRC may further include a driving transistor for generating a driving current and a compensation transistor or compensation capacitor for compensating for a threshold voltage. Furthermore, the pixel circuit DRC may also include a driving transistor for generating a driving current and a light-emitting control transistor for controlling the light-emitting time of the light-emitting diode. Additionally, the pixel circuit DRC may also include a driving transistor for generating a driving current and a voltage control transistor for applying an initialization voltage or bias voltage to a specific node.

[0101] As described above, this disclosure can improve the aperture ratio based on subpixel binarization and by receiving data voltage and reference voltage through a single data line, thereby extending the lifespan of the display panel and improving display quality. Furthermore, this disclosure can delay the degradation characteristics of transistors, such that when one of the two transistors is on, the other transistor is off based on opposite voltage conditions, thus contributing to extending the lifespan of the device.

[0102] The effects of this disclosure are not limited to the examples above, and various other effects may be included in the specification.

[0103] While this disclosure has been specifically shown and described with reference to exemplary embodiments thereof, those skilled in the art will understand that various changes in form and detail may be made therein without departing from the spirit and scope of this disclosure as defined by the appended claims.

Claims

1. A display device, comprising: A display panel, the display panel including sub-pixels; as well as A driver configured to drive the display panel. The sub-pixels include: A sensing transistor configured to transmit a reference voltage applied via a data line to a second electrode of a capacitor during a first time period included in the horizontal time period; and A switching transistor configured to deliver a data voltage applied through the data line to the first electrode of the capacitor during a second time period included in the horizontal time period.

2. The display device according to claim 1, wherein, The sensing transistor includes: a first electrode connected to the data line; a gate electrode connected to a first sensing line included in the first gate line; and a second electrode connected to the second electrode of the capacitor. The switching transistor includes: a first electrode connected to the data line; a gate electrode connected to the first scan line included in the first gate line; and a second electrode connected to the first electrode of the capacitor.

3. The display device according to claim 2, wherein, The sub-pixel also includes: A driving transistor, the driving transistor comprising: a gate electrode connected to a second electrode of the switching transistor and a first electrode of the capacitor; a first electrode connected to a high-level voltage line; and a second electrode connected to a second electrode of the capacitor and a second electrode of the sensing transistor; and A light-emitting diode, comprising an anode electrode and a cathode electrode, wherein the anode electrode is connected to the second electrode of the sensing transistor, the second electrode of the driving transistor and the second electrode of the capacitor, and the cathode electrode is connected to a low-level voltage line.

4. The display device according to claim 1, wherein, The sensing transistor and the switching transistor have time periods during which they perform opposite operations in response to a first gate signal applied through the first gate line.

5. The display device according to claim 1, wherein, The sensing transistor and the switching transistor have a period during which the sensing transistor and the switching transistor are simultaneously turned off in response to a first gate signal applied through the first gate line.

6. The display device according to claim 4, wherein, Each of the sensing transistor and the switching transistor is implemented as a CMOS type including PMOS and NMOS, wherein the sensing transistor is implemented as one of PMOS and NMOS, and the switching transistor is implemented as the other of PMOS and NMOS.

7. The display device according to claim 4, wherein, The sensing transistor includes: a first electrode connected to the data line; a gate electrode connected to the first gate line; and a second electrode connected to the second electrode of the capacitor. The switching transistor includes: a first electrode connected to the data line; a gate electrode connected to the first gate line; and a second electrode connected to the first electrode of the capacitor.

8. The display device according to claim 7, wherein, The sensing transistor is turned on based on the first gate signal of the second voltage applied through the first gate line. The switching transistor is turned on based on the first gate signal, which is a first voltage applied through the first gate line. Wherein, the sensing transistor and the switching transistor are simultaneously turned off based on the first gate signal of the third voltage applied through the first gate line, and The first voltage, the second voltage, and the third voltage have different voltage levels.

9. A driving method for a display device, the driving method comprising: The step of turning on the sensing transistor to transfer the reference voltage applied through the data line to the second electrode of the capacitor during a first time period included in the horizontal time period; The step of turning on the switching transistor to deliver the data voltage applied through the data line to the first electrode of the capacitor during a second time period included in the horizontal time period; as well as The steps of driving a driving transistor based on the voltage difference between the data voltage stored in the capacitor and the reference voltage, and enabling a light-emitting diode to emit light based on the driving current generated from the driving transistor.

10. The driving method according to claim 9, wherein, The sensing transistor includes: a first electrode connected to the data line; a gate electrode connected to a first sensing line included in the first gate line; and a second electrode connected to the second electrode of the capacitor. The switching transistor includes: a first electrode connected to the data line; a gate electrode connected to the first scan line included in the first gate line; and a second electrode connected to the first electrode of the capacitor.

11. The driving method according to claim 9, wherein, The sensing transistor includes: a first electrode connected to the data line; a gate electrode connected to the first gate line; and a second electrode connected to the second electrode of the capacitor. The switching transistor includes: a first electrode connected to the data line; a gate electrode connected to the first gate line; and a second electrode connected to the first electrode of the capacitor.

12. The driving method according to claim 11, wherein, The sensing transistor is turned on based on a first gate signal of a second voltage applied through the first gate line. The switching transistor is turned on based on the first gate signal, which is a first voltage applied through the first gate line. Wherein, the sensing transistor and the switching transistor are simultaneously turned off based on the first gate signal of the third voltage applied through the first gate line, and The first voltage, the second voltage, and the third voltage have different voltage levels.

13. The driving method according to claim 10, wherein: The driving transistor includes: a gate electrode connected to the second electrode of the switching transistor and the first electrode of the capacitor; a first electrode connected to a high-level voltage line; and a second electrode connected to the second electrode of the capacitor and the second electrode of the sensing transistor; and The light-emitting diode includes: an anode electrode connected to the second electrode of the sensing transistor, the second electrode of the driving transistor, and the second electrode of the capacitor; and a cathode electrode connected to a low-level voltage line.

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