Sensing unit and display device including the same

Abstract

The invention relates to a sensing unit and a display device including the same. According to an embodiment of the present disclosure, a sensing unit includes: a sensing line receiving a pixel current from a pixel; a current sink unit connected to the sensing line and receiving a sink current from the sensing line; and a current integrator connected to the sensing line and generating an output voltage using the control current supplied from the sensing line, and the current sink unit changing an amount of current of the sink current in response to the output voltage.

Description

[0001] This application claims priority to Korean Patent Application No. 10-2023-0149341 filed on November 1, 2023 and all rights and benefits derived therefrom, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0002] The present disclosure relates to a sensing unit and a display device including the sensing unit. Background Art

[0003] As information technology develops, the importance of display devices as a connection medium between users and information has become prominent. In response to this, the use of display devices such as liquid crystal display devices and organic light emitting display devices is increasing.

[0004] The pixels of the display device deteriorate according to the total use time and display brightness, etc., and therefore require correction of data (grayscale correction). For this reason, an external compensation method is being used that receives a predetermined voltage (and / or current) from the pixel and uses the received voltage to correct the data. Summary of the invention

[0005] An object of the present disclosure is to provide a sensing unit capable of generating desired sensing data regardless of a deviation of a circuit element included in the sensing unit and a display device including the sensing unit.

[0006] According to an embodiment of the present disclosure, a sensing unit includes: a sensing line that receives a pixel current from a pixel; a current injection unit that is connected to the sensing line and receives an injection current from the sensing line; and a current integrator that is connected to the sensing line and generates an output voltage using a control current supplied from the sensing line, and the current injection unit changes the current amount of the injection current in response to the output voltage.

[0007] According to an embodiment, the control current corresponds to a difference between the pixel current and the sink current.

[0008] According to an embodiment, when the pixel current is greater than the sink current, the output voltage decreases, and the current sink unit increases the sink current in response to the output voltage.

[0009] According to an embodiment, when the pixel current is less than the sink current, the output voltage increases, and the current sink unit reduces the sink current in response to the output voltage.

[0010] According to an embodiment, when the pixel current and the sink current are the same, the output voltage maintains a constant voltage.

[0011] According to an embodiment, the sensing unit further includes: a voltage storage unit storing the output voltage; and an analog-to-digital converter generating the sensing data using the output voltage stored in the voltage storage unit.

[0012] According to an embodiment, a voltage storage unit includes an input switch and an output switch connected in series between an output terminal of a current integrator and an analog-to-digital converter; and a holding capacitor connected between a common terminal of the input switch and the output switch and a ground.

[0013] According to an embodiment, a current integrator includes: an operational amplifier, an inverting input terminal of the operational amplifier is connected to a sensing line, and a non-inverting input terminal of the operational amplifier receives a voltage of a reference power supply; a feedback capacitor connected between the inverting input terminal and an output terminal of the operational amplifier; and a reset switch connected in parallel with the feedback capacitor between the inverting input terminal and the output terminal of the operational amplifier.

[0014] According to an embodiment, the sensing unit further includes: a first switch connected between the sensing line and the current integrator; and a second switch connected between a common node between the first switch and the current integrator and the current sinking unit.

[0015] According to an embodiment, the sensing unit further includes a current source unit connected to the sensing line and configured to supply a source current to the sensing line.

[0016] According to an embodiment, the current source unit controls the current amount of the source current in response to the output voltage.

[0017] According to an embodiment, the control current corresponds to a value obtained by subtracting the sink current from the sum of the pixel current and the source current.

[0018] According to an embodiment of the present disclosure, a display device includes: a pixel connected to a scan line, a data line, and a sensing line; a data driver configured to supply a data signal to the data line during a display period and supply a reference data signal to the data line during a sensing period; a sensing unit connected to the sensing line and configured to generate sensing data during the sensing period; and a timing controller configured to receive input data and control output data supplied to the data driver in response to the sensing data. A sensing channel of the sensing unit includes: a current injection unit connected to a sensing line that receives a pixel current from a pixel in response to a reference data signal and receives a sink current from the sensing line; and a current integrator connected to the sensing line and generates an output voltage using a control current supplied from the sensing line, and the current injection unit changes the current amount of the sink current in response to the output voltage.

[0019] According to an embodiment, the control current corresponds to a difference between the pixel current and the sink current.

[0020] According to an embodiment, when the pixel current is greater than the sink current, the output voltage decreases, and the current sink unit increases the sink current in response to the output voltage.

[0021] According to an embodiment, when the pixel current is less than the sink current, the output voltage increases, and the current sink unit reduces the sink current in response to the output voltage.

[0022] According to an embodiment, when the pixel current and the sink current are the same, the output voltage maintains a constant voltage.

[0023] According to an embodiment, the sensing channel further includes: a voltage storage unit storing the output voltage; and an analog-to-digital converter generating the sensing data using the output voltage stored in the voltage storage unit.

[0024] According to an embodiment, the analog-to-digital converter is connected to the plurality of sensing channels.

[0025] According to an embodiment, a voltage storage unit includes an input switch and an output switch connected in series between an output terminal of a current integrator and an analog-to-digital converter; and a holding capacitor connected between a common terminal of the input switch and the output switch and a ground.

[0026] According to an embodiment, a current integrator includes: an operational amplifier, an inverting input terminal of the operational amplifier is connected to a sensing line, and a non-inverting input terminal of the operational amplifier receives a voltage of a reference power supply; a feedback capacitor connected between the inverting input terminal and an output terminal of the operational amplifier; and a reset switch connected in parallel with the feedback capacitor between the inverting input terminal and the output terminal of the operational amplifier.

[0027] According to an embodiment, the sensing channel further includes: a first switch connected between the sensing line and the current integrator; and a second switch connected between a common node between the first switch and the current integrator and the current sink unit.

[0028] According to an embodiment, the sensing channel further includes a current source unit connected to the sensing line and configured to supply a source current to the sensing line.

[0029] According to an embodiment, the current source unit controls the current amount of the source current in response to the output voltage.

[0030] According to an embodiment, the control current corresponds to a value obtained by subtracting the sink current from the sum of the pixel current and the source current.

[0031] According to an embodiment of the present disclosure, a display device includes: a pixel unit including a plurality of pixels; a data driver connected to the pixels through a data line; and a sensing unit connected to the pixels through a sensing line. A sensing channel of the sensing unit includes: a current injection unit connected to a sensing line receiving a pixel current from a pixel and receiving a injection current from the sensing line; and a current integrator connected to the sensing line and generating an output voltage using a control current supplied from the sensing line, and the data driver supplies a voltage of a data signal corresponding to the output voltage of the current integrator to the pixel via the data line.

[0032] According to an embodiment, the data driver supplies the output voltage as the voltage of the data signal to the data line.

[0033] According to an embodiment, the control current corresponds to a difference between the pixel current and the sink current.

[0034] According to an embodiment, the pixel current is changed in response to the output voltage of the current integrator.

[0035] According to an embodiment, when the pixel current is greater than the sink current, the output voltage decreases, and the pixel current decreases in response to the decrease in the output voltage.

[0036] According to an embodiment, when the pixel current is less than the sink current, the output voltage increases, and the pixel current increases in response to the increase in the output voltage.

[0037] According to an embodiment, when the pixel current and the sink current are the same, the output voltage maintains a constant voltage, and the pixel current is also maintained constant in response to the constant output voltage.

[0038] According to an embodiment, the display device further includes an analog-to-digital converter generating sensing data using the output voltage.

[0039] According to an embodiment, the sink current corresponds to a pixel current that needs to flow to a pixel when the pixel is driven at a predetermined grayscale, and the sensing data corresponds to output data of the pixel corresponding to the predetermined grayscale.

[0040] According to an embodiment, the display device further includes a timing controller generating output data corresponding to remaining grayscales except for the predetermined grayscale in response to the sensing data.

[0041] According to an embodiment, the display device further includes a determiner connected to the analog-to-digital converter and configured to supply a control signal to the timing controller when the sensing data maintains the same value during a predetermined time.

[0042] According to an embodiment, a current integrator includes: an operational amplifier, an inverting input terminal of the operational amplifier is connected to a sensing line, and a non-inverting input terminal of the operational amplifier receives a voltage of a reference power supply; a feedback capacitor connected between the inverting input terminal and an output terminal of the operational amplifier; and a reset switch connected in parallel with the feedback capacitor between the inverting input terminal and the output terminal of the operational amplifier.

[0043] According to an embodiment, the display device further includes: a first switch connected between the pixel and the current integrator; and a second switch connected between the current integrator and the current sinking unit.

[0044] According to an embodiment, a data driver includes: a signal generator for supplying a data signal to a data line; a buffer connected between the signal generator and the data line; a first input switch connected between the buffer and a current integrator; and a second input switch connected between the buffer and the signal generator.

[0045] According to an embodiment, a current sink unit includes: at least two current sources; and a control switch connected between each of the current sources and a sensing line, and turn-on times of the control switches do not overlap.

[0046] According to an embodiment, each of the at least two current sources receives a sink current having a different current amount from the sensing line.

[0047] According to an embodiment, the display device further includes a digital buffer receiving the output voltage from the current integrator, and a microcontroller generating sensing data using an output value of the digital buffer, and a data driver generating a voltage of a data signal corresponding to the output voltage using the sensing data.

[0048] According to an embodiment, the sink current corresponds to a pixel current that needs to flow to a pixel when the pixel is driven at a predetermined grayscale, and the sensing data corresponds to output data of the pixel corresponding to the predetermined grayscale.

[0049] According to an embodiment, the display device further includes a timing controller generating output data corresponding to remaining grayscales except for the predetermined grayscale in response to the sensing data.

[0050] According to an embodiment, the display device further includes a determiner connected to the microcontroller and configured to supply a control signal to the timing controller when the sensing data maintains the same value during a predetermined time.

[0051] According to an embodiment of the present disclosure, a display device includes: a pixel; a data driver connected to the pixel through a data line; a timing controller for supplying output data to the data driver in response to compensation data; and a sensing unit connected to the pixel via a sensing line and including a current integrator that generates an output voltage using a control current supplied from the pixel, and when the output voltage maintains a constant value during a predetermined time, sensing data generated in response to the output voltage is stored in the timing controller as compensation data.

[0052] According to an embodiment, the display device further includes: an analog-to-digital converter generating sensing data using an output voltage of the current integrator; and a determiner connected to the analog-to-digital converter and configured to supply a control signal to the timing controller when the sensing data maintains a constant value during a predetermined time.

[0053] According to an embodiment, the display device further includes: a digital buffer receiving an output voltage from the current integrator; a microcontroller generating sensing data using an output value of the digital buffer; and a determiner connected to the microcontroller and configured to supply a control signal to the timing controller when the sensing data maintains a constant value during a predetermined time.

[0054] The objects of the present disclosure are not limited to the above objects, and other technical objects not described will be clearly understood by those skilled in the art from the following description.

[0055] According to the sensing unit and the display device including the sensing unit according to the embodiment of the present disclosure, the desired sensing data can be generated regardless of the deviation of the circuit element. In addition, in the embodiment of the present disclosure, the sensing data can have a data (or output data) value corresponding to the pixel current that needs to flow to the pixel, and thus the reliability of the external compensation can be improved.

[0056] However, the effects of the present disclosure are not limited to the above-mentioned effects, and may be variously extended within a range not departing from the spirit and scope of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The above and other features of the present disclosure will become more apparent by describing the embodiments of the present disclosure in more detail with reference to the accompanying drawings, in which:

[0058] Figure 1 is a diagram illustrating a display device according to an embodiment of the present disclosure;

[0059] Figure 2 is a diagram illustrating a pixel according to an embodiment of the present disclosure;

[0060] Figure 3 is a diagram illustrating a sensing channel of a sensing unit according to an embodiment of the present disclosure;

[0061] Figure 4 It is a graphic driver Figure 3 A waveform diagram of the method of sensing a channel shown in FIG.

[0062] Figure 5 It is a graphic Figure 3 FIG. 4 is a diagram of simulation results of a sensing unit shown in FIG. 4 ;

[0063] Figure 6 is a diagram illustrating a sensing channel of a sensing unit according to an embodiment of the present disclosure;

[0064] Figure 7 is a diagram illustrating a display device according to an embodiment of the present disclosure;

[0065] Figure 8 It is a graphic Figure 7 FIG. 1 is a diagram of an embodiment of a sensing channel and a data driver of a sensing unit shown in FIG. 1 ;

[0066] Fig. 9 It is a graphic driver Figure 8 A waveform diagram of the method of sensing a channel shown in FIG.

[0067] Fig.10 It is a graphic Figure 8 FIG. 4 is a diagram of simulation results of a sensing unit shown in FIG. 4 ;

[0068] Fig.11 It is a graphic Figure 7 FIG. 1 is a diagram of an embodiment of a sensing channel and a data driver of a sensing unit shown in FIG. 1 ;

[0069] Fig.12 It is a graphic Figure 7 A diagram of an embodiment of a sensing channel and a data driver of a sensing unit shown in FIG.

[0070] Fig.13 It is a graphic Figure 7 FIG. 4 is a diagram of an embodiment of a sensing channel and a data driver of a sensing unit shown in FIG. DETAILED DESCRIPTION

[0071] Hereinafter, various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the present disclosure. The present disclosure can be implemented in various different forms and is not limited to the embodiments described herein.

[0072] In order to clearly describe the present disclosure, parts not related to the description are omitted, and the same or similar elements are represented by the same reference numerals throughout the specification. Therefore, the above reference numerals may be used in other drawings.

[0073] In addition, for the convenience of description, the size and thickness of each component shown in the drawings are arbitrarily shown, and therefore the present disclosure is not necessarily limited to the size and thickness shown in the drawings. In the drawings, the thickness may be exaggerated to clearly indicate various layers and regions.

[0074] In addition, the expression "same" in the description may mean "substantially the same". That is, the expression "same" may be sufficient for a person of ordinary skill to understand that it is the same. Other expressions may also be expressions in which "substantially" is omitted.

[0075] Some embodiments related to functional blocks, units and / or modules are described in the accompanying drawings. Those skilled in the art will appreciate that such blocks, units and / or modules are physically implemented by logic circuits, separate components, microprocessors, hard-wired circuits, storage elements, line connections and other electronic circuits. This can be formed using semiconductor-based manufacturing techniques or other manufacturing techniques. Blocks, units and / or modules implemented by microprocessors or other similar hardware can be programmed and controlled using software to perform various functions discussed herein, and can be optionally driven by firmware and / or software. In addition, each block, unit and / or module can be implemented by a combination of dedicated hardware or dedicated hardware that performs some functions and a processor (e.g., one or more programmed microprocessors and related circuits) that performs functions different from the functions of the dedicated hardware. In addition, in some embodiments, blocks, units and / or modules can be physically separated into two or more interactive, separate blocks, units and / or modules without departing from the scope of the inventive concept. In addition, in some embodiments, blocks, units and / or modules can be physically combined into more complex blocks, units and / or modules without departing from the scope of the inventive concept.

[0076] The term "connection" between two structures may be used to mean both electrical connection and physical connection inclusively, but is not limited thereto. For example, "connection" used based on a circuit diagram may mean electrical connection, and "connection" used based on a cross-sectional view and a plan view may mean physical connection.

[0077] Although "first" and "second" etc. are used to describe various components, these components are not limited by these terms. These terms are only used to distinguish one component from another component. Therefore, within the technical spirit of the present disclosure, the first component described below may be the second component. Unless the context clearly indicates otherwise, a singular expression includes a plural expression.

[0078] Meanwhile, the present disclosure is not limited to the embodiments disclosed below, and may be modified and implemented in various forms. In addition, each of the embodiments disclosed below may be implemented alone or in combination with at least one of the other embodiments.

[0079] Figure 1is a diagram illustrating a display device according to an embodiment of the present disclosure.

[0080] refer to Figure 1 , the display device 10 according to an embodiment of the present disclosure may include a timing controller 11, a data driver 12, a scan driver 13, a pixel unit 14 (or a display panel), and a sensing unit 15. The above configurations may be implemented as separate integrated circuits, and two or more of the above configurations may be integrated and implemented as one integrated circuit. In addition, the scan driver 13 may be formed in the pixel unit 14.

[0081] The pixel unit 14 may include pixels PX (here, n and m are natural numbers greater than 0) connected to first scan lines SL11, SL12, ... and SL1n, second scan lines SL21, SL22, ... and SL2n, data lines DL1, DL2, DL3, ... and DLm, sensing lines IL1, IL2, IL3, ... and ILm, and power lines PL1 and PL2.

[0082] For example, the pixel PXij (refer to Figure 2 ) can be connected to the i-th first scan line SL1i, the i-th second scan line SL2i, the j-th data line DLj and the j-th sensing line ILj (here, i is a natural number less than n, and j is a natural number less than m).

[0083] The pixel PX may be driven in two different periods such as a display period and a sensing period. The display period may be a period in which a predetermined image is displayed in the pixel PX. The sensing period may be a period in which a driving transistor (or transistors) included in each of the pixels PX is sensed. Figure 2 The period during which the characteristics (eg, threshold voltage and / or mobility) of the first transistor M1) shown in FIG.

[0084] During the display period, in response to the first scan enable signal supplied to the first scan lines SL11 to SL1n, the pixel PX may be selected in units of horizontal lines (e.g., the pixels PX connected to the same scan line may be classified as one horizontal line (or pixel row)), and the pixel PX selected by the first scan enable signal may receive a data signal from a data line (any one of the data lines DL1 to DLm) connected to the selected pixel PX. The pixel PX receiving the data signal may generate light of a predetermined brightness in response to the voltage of the data signal.

[0085] During the sensing period, the reference data signal may be supplied to the data lines DL1 to DLm. In addition, during the sensing period, the enable first scan signal may be supplied to at least one scan line (at least one of the first scan lines SL11 to SL1n). The pixel PX receiving the enable first scan signal may supply a pixel current to the sensing lines IL1 to ILm in response to the reference data signal. The sensing unit 15 may generate sensing data Sdata using the pixel current supplied to the sensing lines IL1 to ILm, and supply the sensing data Sdata to the timing controller 11.

[0086] The scan driver 13 may receive a scan driving signal SCS from the timing controller 11. The scan driving signal SCS may include at least one scan start signal and a clock signal required to drive the scan driver 13. The scan driver 13 may generate an enable first scan signal and an enable second scan signal while shifting the scan start signal in response to the clock signal.

[0087] For example, the scan driver 13 may sequentially supply the first enable scan signal to the first scan lines SL11 to SL1n, and sequentially supply the second enable scan signal to the second scan lines SL21 to SL2n. When the first enable scan signal is not supplied to the first scan lines SL11 to SL1n, the scan driver 13 may supply the first disable scan signal. When the second enable scan signal is not supplied to the second scan lines SL21 to SL2n, the scan driver 13 may supply the second disable scan signal.

[0088] Enabling the first scan signal and enabling the second scan signal may mean a gate-on voltage that can turn on a transistor included in the pixel PX. For example, in an N-type transistor, enabling the first scan signal and enabling the second scan signal may be a high-level voltage. Disabling the first scan signal and disabling the second scan signal may mean a gate-off voltage that can turn off a transistor included in the pixel PX. For example, in an N-type transistor, disabling the first scan signal and disabling the second scan signal may be a low-level voltage.

[0089] exist Figure 1 In the embodiment, the first scan lines SL11 to SL1n and the second scan lines SL21 to SL2n are driven by one scan driver 13, but the embodiments of the present disclosure are not limited thereto. For example, the respective first scan lines SL11 to SL1n and the second scan lines SL21 to SL2n may be driven by different scan drivers.

[0090] The data driver 12 may receive output data Dout and a data driving signal DCS from the timing controller 11. The data driving signal DCS may include a sampling signal and / or a timing signal required to drive the data driver 12. The data driver 12 may generate a data signal based on the data driving signal DCS and the output data Dout.

[0091] In an embodiment, during the display period, the data driver 12 may generate a data signal based on the output data Dout and supply the data signal to the data lines DL1 to DLm. In this case, an image corresponding to the output data Dout may be displayed in the pixel unit 14. During the sensing period, the data driver 12 may supply a reference data signal to at least one data line (at least one of the data lines DL1 to DLm). The reference data signal may have a preset voltage to sense the characteristics of the driving transistor included in each of the pixels PX.

[0092] The timing controller 11 may receive input data Din and a control signal CS from the host system through an interface. For example, the timing controller 11 may receive input data Din and a control signal CS from at least one of a graphics processing unit (GPU), a central processing unit (CPU), and an application processor (AP) included in the host system. The control signal CS may include various signals including a clock signal.

[0093] The timing controller 11 may generate a scan driving signal SCS, a data driving signal DCS, and a sensing driving signal ICS based on a control signal CS. The scan driving signal SCS, the data driving signal DCS, and the sensing driving signal ICS may be supplied to the scan driver 13, the data driver 12, and the sensing unit 15, respectively.

[0094] The timing controller 11 may rearrange the input data Din to fit the specification of the display device 10. In addition, the timing controller 11 may correct the input data Din to generate the output data Dout, and supply the output data Dout to the data driver 12. For example, the timing controller 11 may generate the output data Dout by correcting the input data Din in response to the sensing data Sdata supplied from the sensing unit 15. In this case, the input data Din may be corrected in consideration of the threshold voltage and / or mobility of the driving transistor included in each of the pixels PX.

[0095] The sensing unit 15 may receive a sensing driving signal ICS from the timing controller 11. The sensing driving signal ICS may include a switch control signal for controlling turning on and off of a switch included in the sensing unit 15.

[0096] During the display period, the sensing unit 15 may supply a constant voltage (eg, a reference voltage) to the sensing lines IL1 to ILm. During the sensing period, the sensing unit 15 may receive a pixel current from at least one sensing line (at least one of the sensing lines IL1 to ILm).

[0097] The sensing unit 15 may include a sensing channel corresponding to each of the sensing lines IL1 to ILm. Each of the sensing channels may receive sensing data Sdata from a corresponding one of the sensing lines (a corresponding one of the sensing lines IL1 to ILm) and supply the generated sensing data Sdata to the timing controller 11. The sensing data Sdata may include threshold voltage and / or mobility information of a driving transistor included in each of the pixels PX.

[0098] At the same time, the sensing channel can be connected to at least two sensing lines (at least two of the sensing lines IL1 to ILm). In this case, the sensing channel can sequentially (or in a time-division manner) receive at least two pixel currents during the sensing period, and can sequentially generate sensing data Sdata in response to the supplied pixel currents.

[0099] The first driving power VDD may be supplied to the first power line PL1, and the second driving power VSS may be supplied to the second power line PL2. The first driving power VDD may be a power supply that supplies a driving current to the pixel PX. The second driving power VSS may be a power supply that receives a driving current from the pixel PX. During a period in which the pixel PX is set to an emission state, the first driving power VDD may be set to a voltage higher than a voltage of the second driving power VSS. The first power line PL1 and the second power line PL2 may be commonly connected to the pixel PX, but embodiments of the present disclosure are not limited thereto.

[0100] In an embodiment, the first power line PL1 may include a plurality of power lines, and the plurality of power lines may be connected to different pixels PX. In an embodiment, the second power line PL2 may include a plurality of power lines, and the plurality of power lines may be connected to different pixels PX. That is, in an embodiment of the present disclosure, the pixel PX may be connected to any one of the first power lines PL1 and any one of the second power lines PL2.

[0101] Figure 2 is a diagram illustrating a pixel according to an embodiment of the present disclosure. Figure 2 Pixels located on the i-th horizontal line and the j-th vertical line are shown.

[0102] refer to Figure 2 , a pixel PXij according to an embodiment of the present disclosure may include a light emitting element LD and a pixel circuit for controlling the amount of current supplied to the light emitting element LD.

[0103] The light emitting element LD may be connected between a first power line PL1 supplied with a first driving power VDD and a second power line PL2 supplied with a second driving power VSS. For example, a first electrode (e.g., an anode electrode) of the light emitting element LD may be connected to the first power line PL1 via a second node N12 and a first transistor M1, and a second electrode (e.g., a cathode electrode) of the light emitting element LD may be connected to the second power line PL2. The light emitting element LD may emit light having a brightness corresponding to the driving current supplied from the first transistor M1.

[0104] The light emitting element LD may be an organic light emitting diode. In addition, the light emitting element LD may be an inorganic light emitting diode such as a micro light emitting diode (LED) or a quantum dot LED. In addition, the light emitting element LD may be an element including a mixture of an organic material and an inorganic material. Figure 2 In the embodiment, the pixel PXij includes a single light emitting element LD, but in another embodiment, the pixel PXij may include a plurality of light emitting elements and the plurality of light emitting elements may be connected to each other in series, in parallel, or in series and parallel.

[0105] The pixel circuit may include a first transistor M1, a second transistor M2, a third transistor M3 and a storage capacitor Cst. In an embodiment, the first transistor M1 to the third transistor M3 may be formed as an N-type transistor. However, this is exemplary, and at least one of the first transistor M1 to the third transistor M3 may be replaced by a P-type transistor.

[0106] The first transistor M1 (or driving transistor) is connected between the first power line PL1 and the second node N12. In addition, the gate electrode of the first transistor M1 is connected to the first node N11. The first transistor M1 controls the amount of current supplied from the first driving power VDD to the second driving power VSS via the light emitting element LD in response to the voltage of the first node N11.

[0107] The second transistor M2 is connected between the jth data line DLj and the first node N11. In addition, the gate electrode of the second transistor M2 is connected to the i-th first scan line SL1i. When the enable first scan signal is supplied to the i-th first scan line SL1i, the second transistor M2 is turned on to electrically connect the j-th data line DLj and the first node N11.

[0108] The third transistor M3 is connected between the second node N12 and the jth sensing line ILj. In addition, the gate electrode of the third transistor M3 is connected to the i-th second scan line SL2i. When the enable second scan signal is supplied to the i-th second scan line SL2i, the third transistor M3 is turned on to electrically connect the j-th sensing line ILj and the second node N12.

[0109] The storage capacitor Cst is connected between the first node N11 and the second node N12. The storage capacitor Cst stores a voltage corresponding to a difference between the first node N11 and the second node N12.

[0110] Figure 3 is a diagram illustrating a sensing channel of a sensing unit according to an embodiment of the present disclosure. Figure 3 A sensing channel connected to the j-th sensing line ILj is shown.

[0111] refer to Figure 3 , a sensing channel according to an embodiment of the present disclosure may include a current integrator 152 , a current sink unit 154 , a voltage storage unit 156 , and an analog-to-digital converter (hereinafter, “ADC”).

[0112] The current integrator 152 controls the output voltage Vout in response to the amount of current supplied thereto. The amount of current corresponding to the difference between the pixel current Ip and the sink current Is may be supplied to the current integrator 152. Figure 4 The current integrator 152 may include an operational amplifier OP-AMP, a feedback capacitor Cfb, and a reset switch SWr.

[0113] The operational amplifier OP-AMP may include an inverting input terminal − connected to the j-th sensing line ILj via the first node N1 , a non-inverting input terminal + receiving a reference power source Vref, and an output terminal outputting an output voltage Vout.

[0114] The feedback capacitor Cfb may be connected between the inverting input terminal - and the output terminal. The feedback capacitor Cfb may accumulate the amount of current supplied thereto. The reset switch SWr may be connected in parallel with the feedback capacitor Cfb between the inverting input terminal - and the output terminal. When the reset switch SWr is turned on, the feedback capacitor Cfb may be initialized.

[0115] The current sink unit 154 may receive a sink current Is from the jth sensing line ILj. The current sink unit 154 may control the amount of the sink current Is in response to an output voltage Vout applied to a control terminal of the current sink unit 154. To this end, the current sink unit 154 may be a voltage controlled current source (VCCS).

[0116] The first switch SW1 may be connected between the jth sensing line ILj and the first node N1 (or the inverting input terminal -). The first switch SW1 may remain turned on during the sensing period. The second switch SW2 may be connected between the first node N1 and the current injection unit 154. The second switch SW2 may be turned on during at least a portion of the sensing period.

[0117] The voltage storage unit 156 (or a sample / hold unit) may temporarily store the output voltage Vout. To this end, the voltage storage unit 156 may include a holding capacitor Ch, a third switch SW3 (or an input switch), and a fourth switch SW4 (or an output switch).

[0118] The third switch SW3 may be connected between the output terminal of the operational amplifier OP-AMP and the second node N2. The fourth switch SW4 may be connected between the ADC 158 and the second node N2. During the sensing period, the third switch SW3 and the fourth switch SW4 may be turned on and off so as not to overlap with each other (e.g., the third switch SW3 and the fourth switch SW4 may be turned on and off at different timings) to store the output voltage Vout in the holding capacitor Ch, and the output voltage Vout stored in the holding capacitor Ch is supplied to the ADC 158.

[0119] A first electrode of the holding capacitor Ch may be connected to a second node N2 which is a common node of the third switch SW3 and the fourth switch SW4 , and a second electrode of the holding capacitor Ch may be connected to a ground GND. The holding capacitor Ch may store the output voltage Vout.

[0120] ADC 158 may change the output voltage Vout stored in the holding capacitor Ch into a digital value. The digital value generated by ADC 158 may be supplied to the timing controller 11 as sensing data Sdata. In an embodiment, ADC 158 may be connected to each sensing channel. In another embodiment, ADC 158 may be connected to a plurality of sensing channels.

[0121] Figure 4 It is a graphic driver Figure 3 2 is a waveform diagram of the method of sensing the channel shown in FIG. Figure 4 It may be a one-time sensing waveform for extracting a characteristic value of a pixel PXij during a sensing period.

[0122] refer to Figure 4 , the sensing period may include an initialization period Tinit, a control period Tcl and a sampling period Tsam.

[0123] The initialization period Tinit may be a period in which the feedback capacitor Cfb, the holding capacitor Ch, the j-th sensing line ILj, etc. are initialized to the voltage of the reference power supply Vref. The control period Tcl may be a period in which the output voltage Vout corresponding to the pixel current Ip is generated. The sampling period Tsam may be a period in which the sensing data Sdata corresponding to the output voltage Vout is generated.

[0124] During the sensing period, the first switch SW1 may maintain a turned-on state. When the first switch SW1 is turned on, the j-th sensing line ILj and the first node N1 (ie, the inverting input terminal −) may be electrically connected.

[0125] During the initialization period Tinit, the reset switch SWr may be set to an on state. When the reset switch SWr is set to an on state, the operational amplifier OP-AMP may operate as a unit gain buffer whose gain is 1. Therefore, the voltage of the reference power supply Vref may be output to the output terminal of the operational amplifier OP-AMP.

[0126] When the voltage of the reference power supply Vref is output to the output terminal of the operational amplifier OP-AMP, both ends of the feedback capacitor Cfb may be set to the voltage of the reference power supply Vref, and thus the feedback capacitor Cfb may be initialized. Since the first switch SW1 is turned on during the initialization period Tinit, the j-th sensing line ILj may be initialized to the voltage of the reference power supply Vref. Since the third switch SW3 is turned on during the initialization period Tinit, the voltage of the reference power supply Vref may be supplied to the second node N2, and thus the holding capacitor Ch may be initialized to the voltage of the reference power supply Vref.

[0127] During the initialization period Tinit, the enable first scan signal may be supplied to the i-th first scan line SL1i, and the enable second scan signal may be supplied to the i-th second scan line SL2i. When the enable first scan signal is supplied, the second transistor M2 may be turned on, and thus the reference data signal may be supplied from the j-th data line DLj to the first node N11. When the enable second scan signal is supplied, the third transistor M3 may be turned on, and thus the voltage of the reference power supply Vref may be supplied to the second node N12. Therefore, during the initialization period Tinit, a voltage corresponding to the reference data signal and the reference power supply Vref may be stored in the storage capacitor Cst.

[0128] During the control period Tcl, the supply of the second scan signal may be kept enabled. Therefore, during the control period Tcl, the third transistor M3 may be set to a conductive state, and the pixel current Ip from the pixel PXij may be supplied to the first node N1 via the j-th sensing line ILj. Here, the pixel current Ip may be a current corresponding to the voltage stored in the storage capacitor Cst (i.e., the voltage corresponding to the reference data signal and the reference power supply Vref).

[0129] The second switch SW2 can be turned on during the control period Tcl. When the second switch SW2 is turned on, the current injection unit 154 can be electrically connected to the j-th sensing line ILj via the first node N1. A predetermined injection current Is can flow from the j-th sensing line ILj to the ground GND. In this case, a control current corresponding to the difference between the pixel current Ip and the injection current Is (e.g., Ip - Is) can be supplied to the feedback capacitor Cfb.

[0130] During the control period Tcl, the reset switch SWr is turned off. When the reset switch SWr is turned off, the operational amplifier OP-AMP can be driven as a current integrator. The control current Ip - Is can be supplied to the inverting input terminal - and the feedback capacitor Cfb. When the control current Ip - Is is supplied to the feedback capacitor Cfb, a predetermined voltage can be stored in the feedback capacitor Cfb. The potential difference across the feedback capacitor Cfb increases as the amount of accumulated current increases. Here, due to the characteristics of the operational amplifier OP-AMP, the inverting input terminal - and the non-inverting input terminal + can be short-circuited through virtual ground, and thus the potential difference therebetween can be 0. Therefore, during the control period Tcl, the potential of the inverting input terminal - can maintain the voltage of the reference power supply Vref regardless of the increase in the potential difference of the feedback capacitor Cfb. Therefore, the potential of the output terminal of the operational amplifier OP-AMP can decrease in response to the potential difference across the feedback capacitor Cfb.

[0131] According to such a principle, during the control period Tcl, the control current Ip - Is can be changed to a voltage value (i.e., the output voltage Vout) through the feedback capacitor Cfb. Here, as the control current Ip - Is increases, the voltage difference ΔV between the voltage of the reference power supply Vref and the output voltage Vout can also increase.

[0132] At the same time, the amount of the injection current Is of the current injection unit 154 can be changed in response to the output voltage Vout. In an embodiment, when the pixel current Ip is greater than the injection current Is (i.e., Ip > Is), the output voltage Vout can decrease, and thus the injection current Is can increase.

[0133] In an embodiment, when the pixel current Ip is less than the injection current Is (i.e., Ip < Is), the output voltage Vout can increase, and thus the injection current Is can decrease. In an embodiment, when the pixel current Ip is equal to the injection current Is (i.e., Ip = Is), the output voltage Vout can maintain a constant voltage, and thus the injection current Is can also maintain a constant current value. That is, during the control period Tcl, the injection current Is can become equal to the pixel current Ip, and the output voltage Vout can maintain a stable state (or a constant voltage).

[0134] Finally, the output voltage Vout may be determined in response to the amount of the pixel current Ip. Therefore, the output voltage Vout may include the threshold voltage information (and / or mobility) of the first transistor M1. The third switch SW3 remains in the on state during the control period Tcl. Therefore, the output voltage Vout may be stored in the holding capacitor Ch.

[0135] The fourth switch SW4 is turned on during the sampling period Tsam. When the fourth switch SW4 is turned on, the output voltage Vout stored in the holding capacitor Ch may be supplied to the ADC 158. The ADC 158 may generate sensing data Sdata using the output voltage Vout and supply the generated sensing data Sdata to the timing controller 11.

[0136] At the same time, the above-mentioned output voltage Vout can be determined regardless of the deviation of the circuit elements included in the current integrator 152 (for example, the gain of the operational amplifier OP-AMP or the capacitance of the feedback capacitor Cfb). For example, even if the capacitance of the feedback capacitor Cfb changes, only the time ΔT for stabilizing the output voltage Vout is changed, and the voltage value does not change. Therefore, in an embodiment of the present disclosure, the sensing data Sdata can be generated regardless of the deviation of the circuit elements included in the sensing unit 15.

[0137] Figure 5 It is a graphic Figure 3 FIG. 4 is a diagram of simulation results of a sensing unit shown in FIG. Figure 5 , the Y-axis of the graph represents the amount (eg, nA) of the pixel current Ip and the sink current Is, and the X-axis represents time (eg, μs).

[0138] refer to Figure 5 , after a predetermined time, the sink current Is has a value equal to the pixel current Ip. Here, the time when the sink current Is has a deviation value of about 1% compared with the pixel current Ip may be about 57.76 μs. That is, in an embodiment of the present disclosure, the sink current Is may be set to be similar or equal to the pixel current Ip in a short time, and thus the output voltage Vout may be generated in a short time. Therefore, in an embodiment of the present disclosure, the sensing data Sdata may be generated in a state in which the output voltage Vout is stable, and thus the reliability of the external compensation may be improved.

[0139] Figure 6 is a diagram illustrating a sensing channel of a sensing unit according to an embodiment of the present disclosure. Figure 6 A sensing channel connected to the j-th sensing line ILj is shown. Figure 6 , omitting Figure 3 Duplicate description.

[0140] refer to Figure 6 , the sensing channel according to an embodiment of the present disclosure may include a current integrator 152 , a current sink unit 154 , a current source unit 155 , a voltage storage unit 156 , and an ADC 158 .

[0141] The current source unit 155 may supply a source current Iso to the jth sensing line ILj. For example, the current source unit 155 may supply the source current Iso to the jth sensing line ILj from a voltage source (Vcc). In an embodiment, the current source unit 155 may control the current amount of the source current Iso in response to the output voltage Vout. In an embodiment, the amount of the source current Iso may be different from the amount of the sink current Is.

[0142] In this case, the control current supplied to the current integrator 152 during the control period Tcl may be set to Ip-(Is-Iso), and the driving Figure 6 The sensing channel method shown in the figure can be driven with Figure 3 The method of sensing channels shown in is basically the same. That is, Figure 6 The sensing channel shown in FIG. 1 may further include a current source unit 155 and only use the source current Iso to control the current amount of the control current supplied to the current integrator 152, and the basic driving method is the same as that of FIG. Figure 3 The driving method of the sensing channel shown in is the same.

[0143] Figure 7 1 is a diagram illustrating a display device according to an embodiment of the present disclosure. Figure 7 , omitting Figure 1 Duplicate description.

[0144] refer to Figure 7 , the display device 10a according to an embodiment of the present disclosure may include a timing controller 11a, a data driver 12a, a scan driver 13, a pixel unit 14 (or a display panel), and a sensing unit 15a. The above configurations may be implemented as separate integrated circuits, and two or more of the above configurations may be integrated and implemented as one integrated circuit. In addition, the scan driver 13 may be formed in the pixel unit 14.

[0145] The data driver 12a may receive output data Dout and a data driving signal DCS from the timing controller 11a. The data driving signal DCS may include a sampling signal and / or a timing signal required to drive the data driver 12a. The data driver 12a may generate a data signal based on the data driving signal DCS and the output data Dout.

[0146] In an embodiment, during the display period, the data driver 12 a may generate a data signal based on the output data Dout and supply the data signal to the data lines DL1 to DLm. In this case, an image corresponding to the output data Dout may be displayed in the pixel unit 14 .

[0147] In an embodiment, the data driver 12a may supply a reference data signal to at least one data line (at least one of the data lines DL1 to DLm) during the sensing period. The reference data signal may be supplied to a specific pixel PX connected to a specific sensing channel. In addition, during the sensing period, the data driver 12a may receive feedback of the output voltage Vout from at least one specific sensing channel of the sensing unit 15a, and supply the fed-back output voltage Vout to a specific pixel PX connected to the specific sensing channel. Here, the fed-back output voltage Vout may be a voltage of a data signal corresponding to a predetermined grayscale.

[0148] The sensing unit 15a may receive a sensing driving signal ICS from the timing controller 11a. The sensing driving signal ICS may include a switch control signal for controlling the turning on and off of a switch included in the sensing unit 15a.

[0149] During the display period, the sensing unit 15a may supply a constant voltage (e.g., a reference voltage) to the sensing lines IL1 to ILm. During the sensing period, the sensing unit 15a may receive a pixel current from at least one sensing line (at least one of the sensing lines IL1 to ILm). Each of the sensing channels included in the sensing unit 15a may generate an output voltage Vout in response to the pixel current, and supply the output voltage Vout to the data driver 12a. In addition, when the output voltage Vout maintains a constant voltage, the sensing unit 15a may change the output voltage Vout to the sensing data Sdataa and supply the sensing data Sdataa to the timing controller 11a.

[0150] Here, the sensing data Sdataa may be data (or output data Dout) corresponding to a predetermined gray scale in which the threshold voltage and / or mobility information of the driving transistor included in each of the pixels PX is reflected. For example, when the predetermined gray scale is 150 gray scales, the sensing data Sdataa may be output data Dout to be supplied to a specific pixel PX corresponding to 150 gray scales.

[0151] The timing controller 11a may receive input data Din and a control signal CS from the host system through an interface. For example, the timing controller 11a may receive input data Din and a control signal CS from at least one of a graphics processing unit (GPU), a central processing unit (CPU), and an application processor (AP) included in the host system. The control signal CS may include various signals including a clock signal.

[0152] The timing controller 11a may generate a scan driving signal SCS, a data driving signal DCS, and a sensing driving signal ICS based on a control signal CS. The scan driving signal SCS, the data driving signal DCS, and the sensing driving signal ICS may be supplied to the scan driver 13, the data driver 12a, and the sensing unit 15a, respectively.

[0153] The timing controller 11a may rearrange the input data Din to fit the specification of the display device 10a. In addition, the timing controller 11a may correct the input data Din to generate output data Dout, and supply the output data Dout to the data driver 12a. For example, the timing controller 11a may generate output data Dout by correcting the input data Din in response to the sensing data Sdataa supplied from the sensing unit 15a.

[0154] As described above, the sensing data Sdataa may correspond to the output data Dout corresponding to a predetermined grayscale of a specific pixel PX. The timing controller 11a may generate the output data Dout of the remaining grayscale to be supplied to the specific pixel PX using the sensing data Sdataa corresponding to the predetermined grayscale. Thereafter, the timing controller 11a may select the output data Dout corresponding to the grayscale of the input data Din, and supply the output data Dout to the data driver 12a. In this case, the output data Dout in which the threshold voltage and / or mobility of the driving transistor included in each of the pixels PX is compensated may be supplied to the pixel PX.

[0155] Figure 8 It is a graphic Figure 7 FIG. 4 is a diagram of an embodiment of a sensing channel and a data driver of a sensing unit shown in FIG. Figure 8 A sensing channel connected to the j-th sensing line ILj is shown.

[0156] refer to Figure 8 , the sensing channel according to an embodiment of the present disclosure may include a current integrator 152 , a current sink unit 154 a , an ADC 158 a , and a determiner 159 .

[0157] The current integrator 152 controls the output voltage Vout in response to the amount of current supplied thereto. The amount of current corresponding to the difference between the pixel current Ip and the sink current Isa may be supplied to the current integrator 152. The current integrator 152 may include an operational amplifier OP-AMP, a feedback capacitor Cfb, and a reset switch SWr.

[0158] The operational amplifier OP-AMP may include an inverting input terminal − connected to the j-th sensing line ILj via the first node N1 a , a non-inverting input terminal + receiving a reference power source Vref, and an output terminal outputting an output voltage Vout.

[0159] The feedback capacitor Cfb may be connected between the inverting input terminal - and the output terminal of the operational amplifier OP-AMP. The feedback capacitor Cfb may accumulate the amount of current supplied thereto. The reset switch SWr may be connected in parallel with the feedback capacitor Cfb between the inverting input terminal - and the output terminal of the operational amplifier OP-AMP. When the reset switch SWr is turned on, the feedback capacitor Cfb may be initialized.

[0160] The current injection unit 154a may receive a sink current Isa from the j-th sensing line ILj. Here, the sink current Isa may be set to a constant current value corresponding to a predetermined grayscale. For example, the sink current Isa may be set to a current value corresponding to 150 grayscales.

[0161] The first switch SW1 may be connected between the jth sensing line ILj and the first node N1a (or the inverting input terminal -). The first switch SW1 may remain turned on during the sensing period. The second switch SW2a may be connected between the first node N1a and the current injection unit 154a. The second switch SW2a may be turned on during at least a portion of the sensing period.

[0162] The data driver 12a may include a signal generator 121 and a buffer 122. The buffer 122 may be positioned for each channel of the data driver 12a, and may supply a voltage of a data signal and / or an output voltage Vout to a j-th data line DLj connected to the buffer 122. The signal generator 121 may generate a data signal using the output data Dout, and supply the data signal to the buffer 122. The signal generator 121 may be connected to a plurality of channels of the data driver 12a.

[0163] The data driver 12a may further include a third switch SW3a (or a first input switch) and a fourth switch SW4a (or a second input switch). The third switch SW3a may be connected between the input terminal of the buffer 122 and the output terminal of the operational amplifier OP-AMP. The third switch SW3a may be turned on during at least a portion of the sensing period. The fourth switch SW4a may be connected between the input terminal of the buffer 122 and the signal generator 121. The fourth switch SW4a may be turned on during a portion of the display period and the sensing period. The on-periods of the fourth switch SW4a and the third switch SW3a do not overlap.

[0164] The ADC 158a may be connected to an output terminal of the operational amplifier OP-AMP. The ADC 158a may change the output voltage Vout into sensing data Sdataa which is a digital value.

[0165] The determiner 159 may determine whether the sensing data Sdataa output from the ADC 158a is changed. For example, when the sensing data Sdataa output from the ADC 158a is changed, the determiner 159 may determine that the desired sensing data Sdataa is not output. For example, when the sensing data Sdataa output from the ADC 158a maintains a constant value during a predetermined time, the determiner 159 may determine that the desired sensing data Sdataa is output. The determiner 159 may include a comparator that compares the current sensing data Sdataa output from the ADC 158a with the previous sensing data Sdataa.

[0166] When the desired sensing data Sdataa is output, the determiner 159 may supply a control signal CS1 (eg, a high level voltage or a low level voltage) corresponding thereto to the timing controller 11a. When the control signal CS1 is input, the timing controller 11a may store the sensing data Sdataa and generate the output data Dout using the stored sensing data Sdataa.

[0167] Meanwhile, the current sink unit 154a, the ADC 158a, and the determiner 159 may be included in the sensing unit 15a, but the present disclosure is not limited thereto. For example, at least one of the current sink unit 154a, the ADC 158a, and the determiner 159 may be included in the data driver 12a.

[0168] Fig. 9 It is a graphic driver Figure 8 2 is a waveform diagram of the method of sensing the channel shown in FIG. Fig. 9 It may be a one-time sensing waveform for extracting the sensing data Sdataa of the pixel PXij during the sensing period.

[0169] refer to Fig. 9 , the sensing period may include an initialization period Tinita, a control period Tcla and a sampling period Tsama.

[0170] The initialization period Tinita may be a period in which the voltage of the reference data signal is stored in the pixel PXij. The initialization period Tinita may be a period in which the feedback capacitor Cfb and the j-th sensing line ILj, etc. are initialized to the voltage of the reference power supply Vref. The control period Tcla may be a period in which the output voltage Vout corresponding to the pixel current Ip is generated. The sampling period Tsama may be a period in which the sensing data Sdataa corresponding to the output voltage Vout is generated.

[0171] During the sensing period, the first switch SW1 may maintain a turned-on state. When the first switch SW1 is turned on, the j-th sensing line ILj and the first node N1a (ie, the inverting input terminal −) may be electrically connected.

[0172] During the initialization period Tinita, the reset switch SWr may be set to an on state. When the reset switch SWr is set to an on state, the operational amplifier OP-AMP may operate as a unit gain buffer having a gain of 1. Therefore, the voltage of the reference power supply Vref may be output to the output terminal of the operational amplifier OP-AMP.

[0173] When the voltage of the reference power supply Vref is output to the output terminal of the operational amplifier OP-AMP, both ends of the feedback capacitor Cfb can be set to the voltage of the reference power supply Vref, and thus the feedback capacitor Cfb can be initialized. In addition, since the first switch SW1 is turned on during the initialization period Tinita, the j-th sensing line ILj can be initialized to the voltage of the reference power supply Vref.

[0174] During the initialization period Tinita, the first scan signal may be supplied to the i-th first scan line SL1i, and the second scan signal may be supplied to the i-th second scan line SL2i. In addition, the fourth switch SW4a may be set to an on state during the initialization period Tinita. When the fourth switch SW4a is turned on, the signal generator 121 may be electrically connected to the j-th data line DLj. During the initialization period Tinita, the signal generator 121 may supply a reference data signal to the j-th data line DLj.

[0175] When the first scan signal is supplied and enabled, the second transistor M2 may be turned on, and thus the reference data signal may be supplied from the j-th data line DLj to the first node N11. When the second scan signal is supplied and enabled, the third transistor M3 may be turned on, and thus the voltage of the reference power source Vref may be supplied to the second node N12. Therefore, during the initialization period Tinita, a voltage corresponding to the reference data signal and the reference power source Vref may be stored in the storage capacitor Cst.

[0176] During the control period Tcla, the supply of the first scan signal and the second scan signal may be maintained. When the first scan signal is supplied, the second transistor M2 may be set to an on state during the control period Tcla, and thus the j-th data line DLj may be electrically connected to the first node N11. When the second scan signal is supplied, the third transistor M3 may be set to an on state during the control period Tcla, and the pixel current Ip from the pixel PXij may be supplied to the first node N1a via the j-th sensing line ILj. Here, the pixel current Ip may be a current corresponding to a voltage stored in the storage capacitor Cst (i.e., a voltage corresponding to the reference data signal and the reference power supply Vref).

[0177] The second switch SW2a can be turned on during the control period Tcla. When the second switch SW2a is turned on, the current injection unit 154a can be electrically connected to the j-th sensing line ILj via the first node N1a. The predetermined injection current Isa can flow from the j-th sensing line ILj to the ground GND. In this case, a control current (e.g., Ip-Isa) corresponding to the difference between the pixel current Ip and the injection current Isa can be supplied to the feedback capacitor Cfb. The injection current Isa can be set to a current that needs to flow in the pixel PXij in response to a predetermined grayscale. For example, the injection current Isa can be set to a current that needs to flow in the pixel PXij in response to a 150 grayscale.

[0178] The third switch SW3a may be turned on during the control period Tcla When the third switch SW3a is turned on, the input terminal of the buffer 122 and the output terminal of the operational amplifier OP-AMP may be electrically connected.

[0179] During the control period Tcla, the reset switch SWr is turned off. When the reset switch SWr is turned off, the operational amplifier OP-AMP can be driven as a current integrator. The control current Ip-Isa can be supplied to the inverting input terminal - and the feedback capacitor Cfb. When the control current Ip-Isa is supplied to the feedback capacitor Cfb, a predetermined voltage can be stored in the feedback capacitor Cfb. The potential difference across the feedback capacitor Cfb increases as the accumulated current amount increases.

[0180] Here, due to the characteristics of the operational amplifier OP-AMP, the inverting input terminal - and the non-inverting input terminal + can be short-circuited through virtual ground, and thus the potential difference therebetween can be 0. Therefore, during the control period Tcla, the potential of the inverting input terminal - can maintain the voltage of the reference power supply Vref regardless of the increase in the potential difference of the feedback capacitor Cfb. Therefore, the potential of the output terminal of the operational amplifier OP-AMP can decrease in response to the potential difference across the feedback capacitor Cfb.

[0181] According to such a principle, during the control period Tcla, the control current Ip - Isa can be changed to a voltage value (i.e., the output voltage Vout) through the feedback capacitor Cfb. Here, as the control current Ip - Isa increases, the voltage difference ΔV between the voltage of the reference power supply Vref and the output voltage Vout can also increase.

[0182] Meanwhile, the output voltage Vout is supplied to the j-th data line DLj via the buffer 122. The output voltage Vout supplied to the j-th data line DLj can be supplied to the first node N11 of the pixel PXij, and the pixel PXij can supply a pixel current Ip corresponding to the voltage of the first node N11 to the first node N1a. That is to say, the pixel current Ip can be changed in response to the output voltage Vout.

[0183] In an embodiment, when the pixel current Ip is greater than the sink current Isa (i.e., Ip > Isa), the output voltage Vout can decrease. Then, the output voltage Vout supplied to the j-th data line DLj can decrease, and thus the amount of the pixel current Ip can decrease.

[0184] In an embodiment, when the pixel current Ip is less than the sink current Isa (i.e., Ip < Isa), the output voltage Vout can increase. Then, the output voltage Vout supplied to the j-th data line DLj can increase, and thus the amount of the pixel current Ip can increase.

[0185] In an embodiment, when the pixel current Ip and the sink current Isa are equal to each other (i.e., Ip = Isa), the output voltage Vout can maintain a constant voltage. Then, the output voltage Vout supplied to the j-th data line DLj can maintain a constant voltage, and thus the pixel current Ip can also maintain a constant amount.

[0186] That is, during the control period Tcla, the output voltage Vout may be supplied to the pixel PXij, and the pixel current Ip output from the pixel PXij may be changed by the output voltage Vout. In addition, after a certain time ΔT, the pixel current Ip and the sink current Isa may become equal to each other, and in this case, the output voltage Vout may maintain a constant voltage. Here, the output voltage Vout may be set to a voltage corresponding to the sink current Isa (i.e., the voltage of the data signal).

[0187] Specifically, the voltage value of the output voltage Vout is controlled so that the pixel current Ip and the sink current Isa become equal during the control period Tcla. Here, the meaning that the pixel current Ip and the sink current Isa become equal may mean that when the output voltage Vout is supplied to the pixel PXij, the current amount of the sink current Isa flows.

[0188] In order to realize a predetermined grayscale corresponding to the sink current Isa in the pixel PXij during the display period, a data signal corresponding to the output voltage Vout (i.e., a voltage equal to the output voltage) needs to be supplied to the pixel PXij. Here, the output voltage Vout may have a voltage value through which the pixel current Ip corresponding to the sink current Isa flows regardless of the characteristic deviation of the first transistor M1, and thus the characteristic deviation of the first transistor M1 may be compensated.

[0189] During the sampling period Tsama, the ADC 158a may generate sensing data Sdataa using the output voltage Vout supplied from the current integrator 152. The sensing data Sdataa generated by the ADC 158a may be supplied to the timing controller 11a and the determiner 159.

[0190] When the sensing data Sdataa maintains a constant value, the determiner 159 supplies the control signal CS1 to the timing controller 11a. When the control signal CS1 is input, the timing controller 11a stores the sensing data Sdataa. Here, the timing controller 11a may set the sensing data Sdataa to output data Dout of a predetermined grayscale (e.g., 150 grayscale). That is, when the input data Din corresponding to the predetermined grayscale is input, the output data Dout having the same bit value as the sensing data Sdataa may be output. In addition, the timing controller 11a may control the value of the output data Dout corresponding to the remaining grayscale using the sensing data Sdataa corresponding to the predetermined grayscale.

[0191] Meanwhile, the ADC 158a may generate the sensing data Sdataa using the output voltage Vout after a specific time ΔT. The specific time ΔT may be determined in advance according to experiments, and in this case, the determiner 159 may be removed.

[0192] Fig.10 It is a graphic Figure 8 FIG. 4 is a diagram of simulation results of a sensing unit shown in FIG. Fig.10 , the Y-axis of the graph represents the amount (eg, nA) of the pixel current Ip and the sink current Isa, and the X-axis represents time (eg, ms).

[0193] refer to Fig.10 , during the sensing period, the pixel current Ip may have a value similar to or equal to the sink current Isa after a specific time Δt. For example, the pixel current Ip may become similar to or equal to the sink current Isa after about 1 ms. In an embodiment of the present disclosure, since the sink current Isa is set in response to the grayscale to be represented, and the sensing data Sdataa is generated using a voltage (i.e., the output voltage Vout) at which the pixel current Ip becomes equal to the sink current Isa (or similar to the sink current Isa), the reliability of compensation can be improved.

[0194] Fig.11 It is a graphic Figure 7 FIG. 4 is a diagram of an embodiment of a sensing channel and a data driver of a sensing unit shown in FIG. Fig.11 A sensing channel connected to the j-th sensing line ILj is shown. Fig.11 , omitting Figure 8 Duplicate description.

[0195] refer to Fig.11 , the sensing channel according to an embodiment of the present disclosure may include a current integrator 152 , a current sink unit 154 b , an ADC 158 a , and a determiner 159 .

[0196] The current sink unit 154b may include at least two current sources 1541, 1542, and 1543. Each of the plurality of current sources 1541, 1542, and 1543 may receive a sink current Isa having a different current amount from the j-th sensing line ILj.

[0197] The control switch (any one of SWca, SWcb, and SWcc) may be connected between each of the current sources 1541, 1542, and 1543 and the first node N1a (or the inverting input terminal -). For example, the first control switch SWca may be connected between the first current source 1541 and the first node N1a, the second control switch SWcb may be connected between the second current source 1542 and the first node N1a, and the third control switch SWcc may be connected between the third current source 1543 and the first node N1a. During the sensing period, the control switches SWca, SWcb, and SWcc may be turned on so as not to overlap with each other.

[0198] The first current source 1541 may be injected with a current corresponding to a first predetermined grayscale, the second current source 1542 may be injected with a current corresponding to a second predetermined grayscale, and the third current source 1543 may be injected with a current corresponding to a third predetermined grayscale. Here, the first predetermined grayscale, the second predetermined grayscale, and the third predetermined grayscale may be set to different grayscales. For example, the first predetermined grayscale may have a current (i.e., pixel current Ip) value that needs to flow in the pixel PXij when realizing 30 grayscales, the second predetermined grayscale may have a current value that needs to flow in the pixel PXij when realizing 100 grayscales, and the third predetermined grayscale may have a current value that needs to flow in the pixel PXij when realizing 180 grayscales.

[0199] When the first control switch SWca is turned on, the sink current Isa can be set to a current value corresponding to the first predetermined grayscale, and thus the output voltage Vout can be set to a voltage value corresponding to the first predetermined grayscale. ADC158a can supply sensing data Sdataa generated using the output voltage Vout corresponding to the first predetermined grayscale to the timing controller 11a.

[0200] When the second control switch SWcb is turned on, the sink current Isa can be set to a current value corresponding to the second predetermined grayscale, and thus the output voltage Vout can be set to a voltage value corresponding to the second predetermined grayscale. ADC158a can supply sensing data Sdataa generated using the output voltage Vout corresponding to the second predetermined grayscale to the timing controller 11a.

[0201] When the third control switch SWcc is turned on, the sink current Isa can be set to a current value corresponding to the third predetermined grayscale, and thus the output voltage Vout can be set to a voltage value corresponding to the third predetermined grayscale. ADC158a can supply sensing data Sdataa generated using the output voltage Vout corresponding to the third predetermined grayscale to the timing controller 11a.

[0202] That is to say, Fig.11 In the sensing channel shown in FIG. 1 , sensing data Sdataa corresponding to a plurality of grays may be generated during a sensing period. The timing controller 11a may generate data values ​​corresponding to the remaining grays using the sensing data Sdataa corresponding to the plurality of grays. When data values ​​are generated using the sensing data Sdataa corresponding to the plurality of grays, more reliable data values ​​may be generated compared to a case where data values ​​are generated using the sensing data Sdataa corresponding to one gray.

[0203] Fig.12 It is a graphic Figure 7 FIG. 4 is a diagram of an embodiment of a sensing channel and a data driver of a sensing unit shown in FIG. Fig.12 A sensing channel connected to the j-th sensing line ILj is shown. Fig.12 , omitting Figure 8 Duplicate description.

[0204] refer to Fig.12 , the sensing channel according to an embodiment of the present disclosure may include a current integrator 152 , a current sink unit 154 a , a digital buffer 200 , a microcontroller (microcontroller unit (MCU)) 202 , and a determiner 204 .

[0205] The current integrator 152 controls the output voltage Vout in response to the amount of current supplied thereto. The amount of current corresponding to the difference between the pixel current Ip and the sink current Isa may be supplied to the current integrator 152. The current integrator 152 may include an operational amplifier OP-AMP, a feedback capacitor Cfb, and a reset switch SWr.

[0206] The current injection unit 154a may receive an injection current Isa from the j-th sensing line ILj. Here, the injection current Isa may be set to a constant current value corresponding to a predetermined grayscale. For example, the injection current Isa may be set to a current value corresponding to 150 grayscales. The first switch SW1 may be connected between the j-th sensing line ILj and the first node N1a (or the inverting input terminal -). The second switch SW2a may be connected between the first node N1a and the current injection unit 154a.

[0207] The digital buffer 200 may transmit the output voltage Vout to the microcontroller 202 .

[0208] The microcontroller 202 may generate sensing data Sdataa using the output voltage Vout supplied from the digital buffer 200. Here, the sensing data Sdataa may be set to a data value corresponding to the sink current Isa. For example, the sensing data Sdataa may be set to a data value corresponding to the sink current Isa (i.e., output data Dout corresponding to a predetermined grayscale). The sensing data Sdataa generated by the microcontroller 202 may be supplied to the determiner 204, the data driver 12a, and the timing controller 11a.

[0209] The data driver 12a changes the sensing data Sdataa supplied from the microcontroller 202 into a data signal or (voltage of the data signal) and supplies the data signal to the pixel PXij. Then, the pixel PXij may supply a pixel current Ip corresponding to the sensing data Sdataa to the current integrator 152.

[0210] The determiner 204 may determine whether the sensing data Sdataa output from the microcontroller 202 is changed. For example, when the sensing data Sdataa output from the microcontroller 202 is continuously changed, the determiner 204 may determine that the expected sensing data Sdataa is not output. For example, when the sensing data Sdataa output from the microcontroller 202 maintains a constant value during a predetermined time, the determiner 204 may determine that the expected sensing data Sdataa is output.

[0211] When the desired sensing data Sdataa is output, the determiner 204 may supply a control signal CS1 (e.g., a high level voltage or a low level voltage) corresponding thereto to the timing controller 11a. When the control signal CS1 is input, the timing controller 11a may store the supplied sensing data Sdataa and generate output data Dout using the stored sensing data Sdataa.

[0212] Meanwhile, the current sink unit 154a, the microcontroller 202, and the determiner 204 may be included in the sensing unit 15a, but the present disclosure is not limited thereto. For example, at least one of the current sink unit 154a, the microcontroller 202, and the determiner 204 may be included in the data driver 12a.

[0213] Combination Fig. 9 Brief Description Fig.12 During the initialization period Tinita, the reset switch SWr may be set to an on state, and thus the feedback capacitor Cfb may be initialized. In addition, since the first switch SW1 is turned on during the initialization period Tinita, the jth sensing line ILj may be initialized to the voltage of the reference power supply Vref.

[0214] During the initialization period Tinita, the enabled first scan signal may be supplied to the i-th first scan line SL1i, and the enabled second scan signal may be supplied to the i-th second scan line SL2i. During the initialization period Tinita, the data driver 12a may supply a reference data signal to the j-th data line DLj.

[0215] When the first scan signal is supplied and enabled, the second transistor M2 may be turned on, and thus the reference data signal may be supplied from the j-th data line DLj to the first node N11. When the second scan signal is supplied and enabled, the third transistor M3 may be turned on, and thus the voltage of the reference power source Vref may be supplied to the second node N12. Therefore, during the initialization period Tinita, a voltage corresponding to the reference data signal and the reference power source Vref may be stored in the storage capacitor Cst.

[0216] During the control period Tcla, the supply of the first scan signal and the second scan signal may be maintained. When the first scan signal is supplied to be enabled, the second transistor M2 may be in a conductive state during the control period Tcla, and thus the j-th data line DLj may be electrically connected to the first node N11. When the second scan signal is supplied to be enabled, the third transistor M3 may be in a conductive state during the control period Tcla, and the pixel current Ip from the pixel PXij may be supplied to the first node N1a via the j-th sensing line ILj. Here, the pixel current Ip may be a current corresponding to a voltage stored in the storage capacitor Cst (i.e., a voltage corresponding to the reference data signal and the reference power supply Vref).

[0217] The second switch SW2a can be turned on during the control period Tcla. When the second switch SW2a is turned on, the current injection unit 154a can be electrically connected to the j-th sensing line ILj via the first node N1a. The predetermined injection current Isa can flow from the j-th sensing line ILj to the ground GND. In this case, a control current (e.g., Ip-Isa) corresponding to the difference between the pixel current Ip and the injection current Isa can be supplied to the feedback capacitor Cfb. The injection current Isa can be set to a current that needs to flow in the pixel PXij in response to a predetermined grayscale. For example, the injection current Isa can be set to a current that needs to flow in the pixel PXij in response to a 150 grayscale.

[0218] During the control period Tcla, the reset switch SWr is turned off. When the reset switch SWr is turned off, the operational amplifier OP-AMP can be driven as a current integrator. The control current Ip-Isa can be supplied to the inverting input terminal - and the feedback capacitor Cfb. When the control current Ip-Isa is supplied to the feedback capacitor Cfb, a predetermined voltage can be stored in the feedback capacitor Cfb. The potential difference across the feedback capacitor Cfb increases as the accumulated current amount increases.

[0219] Here, due to the characteristics of the operational amplifier OP-AMP, the inverting input terminal - and the non-inverting input terminal + can be short-circuited by a virtual ground, and thus the potential difference therebetween can be 0. Therefore, during the control period Tcla, the potential of the inverting input terminal - can maintain the voltage of the reference power supply Vref regardless of the increase in the potential difference of the feedback capacitor Cfb. Therefore, the potential of the output terminal of the operational amplifier OP-AMP can decrease in response to the potential difference across the feedback capacitor Cfb.

[0220] According to such a principle, during the control period Tcla, the control current Ip-Isa can be changed to a voltage value (i.e., the output voltage Vout) through the feedback capacitor Cfb. Here, as the control current Ip-Isa increases, the voltage difference ΔV between the voltage of the reference power supply Vref and the output voltage Vout can also increase.

[0221] Meanwhile, the output voltage Vout can be supplied to the microcontroller 202 via the digital buffer 200. The microcontroller 202 can use the output voltage Vout to generate sensing data Sdataa and supply the sensing data Sdataa to the data driver 12a. The data driver 12a can use the sensing data Sdataa to generate a data signal and supply the generated data signal to the j-th data line DLj.

[0222] The data signal supplied to the j-th data line DLj can be supplied to the first node N11 of the pixel PXij, and the pixel PXij can supply a pixel current Ip corresponding to the voltage of the first node N11 to the first node N1a. That is, the pixel current Ip can be changed in response to the output voltage Vout.

[0223] In an embodiment, when the pixel current Ip is greater than the sink current Isa (i.e., Ip>Isa), the output voltage Vout can decrease. Then, the voltage of the data signal supplied from the data driver 12a can decrease in response to the output voltage Vout, and thus the amount of the pixel current Ip can decrease.

[0224] In an embodiment, when the pixel current Ip is less than the sink current Isa (i.e., Ip<Isa), the output voltage Vout can increase. Then, the voltage of the data signal supplied from the data driver 12a can increase in response to the output voltage Vout, and thus the amount of the pixel current Ip can increase.

[0225] In an embodiment, when the pixel current Ip and the sink current Isa are equal to each other (i.e., Ip = Isa), the output voltage Vout can maintain a constant voltage. Then, the voltage of the data signal supplied from the data driver 12a can maintain a constant voltage, and thus the pixel current Ip can also maintain a constant amount of current.

[0226] That is, during the control period Tcla, the output voltage Vout is changed to the sensing data Sdataa, and the data driver 12a supplies the data signal corresponding to the sensing data Sdataa to the pixel PXij. Therefore, the pixel current Ip output from the pixel PXij can be changed by the output voltage Vout. In addition, after a certain time ΔT, the pixel current Ip and the sink current Isa may become equal to each other, and in this case, the output voltage Vout may maintain a constant voltage. Here, the output voltage Vout may be set to a voltage corresponding to the sink current Isa.

[0227] The microcontroller 202 may generate the sensing data Sdataa using the output voltage Vout. The sensing data Sdataa generated by the microcontroller 202 may be supplied to the timing controller 11a, the determiner 204, and the data driver 12a.

[0228] When the sensing data Sdataa maintains a constant value (this period may be a sampling period Tsama), the determiner 204 supplies the control signal CS1 to the timing controller 11a. When the control signal CS1 is input, the timing controller 11a stores the sensing data Sdataa. Here, the timing controller 11a may set the sensing data Sdataa to output data Dout of a predetermined grayscale (e.g., 150 grayscale). That is, when the input data Din corresponding to the predetermined grayscale is input, the output data Dout having the same bit value as the sensing data Sdataa may be output. In addition, the timing controller 11a may control the value of the output data Dout corresponding to the remaining grayscale using the sensing data Sdataa corresponding to the predetermined grayscale.

[0229] Meanwhile, the timing controller 11 a may store the input sensing data Sdataa after a specific time ΔT. The specific time ΔT may be determined in advance according to experiments, and in this case, the determiner 204 may be removed.

[0230] Fig.13 It is a graphic Figure 7 FIG. 4 is a diagram of an embodiment of a sensing channel and a data driver of a sensing unit shown in FIG. Fig.13 A sensing channel connected to the j-th sensing line ILj is shown. Fig.13 , omitting Fig.12 Duplicate description.

[0231] refer to Fig.13 , the sensing channel according to an embodiment of the present disclosure may include a current integrator 152 , a current sink unit 154 b , a digital buffer 200 , a microcontroller 202 , and a determiner 204 .

[0232] The current sink unit 154b may include at least two current sources 1541, 1542, and 1543. Each of the plurality of current sources 1541, 1542, and 1543 may receive a sink current Isa having a different current amount from the j-th sensing line ILj.

[0233] The control switch (any one of SWca, SWcb, and SWcc) may be connected between each of the current sources 1541, 1542, and 1543 and the first node N1a (or the inverting input terminal -). For example, the first control switch SWca may be connected between the first current source 1541 and the first node N1a, the second control switch SWcb may be connected between the second current source 1542 and the first node N1a, and the third control switch SWcc may be connected between the third current source 1543 and the first node N1a. During the sensing period, the control switches SWca, SWcb, and SWcc may be turned on so as not to overlap with each other.

[0234] The first current source 1541 may be injected with a current corresponding to a first predetermined grayscale, the second current source 1542 may be injected with a current corresponding to a second predetermined grayscale, and the third current source 1543 may be injected with a current corresponding to a third predetermined grayscale. Here, the first predetermined grayscale, the second predetermined grayscale, and the third predetermined grayscale may be set to different grayscales. For example, the first predetermined grayscale may have a current (i.e., pixel current Ip) value that needs to flow in the pixel PXij when realizing 30 grayscales, the second predetermined grayscale may have a current value that needs to flow in the pixel PXij when realizing 100 grayscales, and the third predetermined grayscale may have a current value that needs to flow in the pixel PXij when realizing 180 grayscales.

[0235] When the first control switch SWca is turned on, the sink current Isa can be set to a current value corresponding to the first predetermined grayscale, and thus the output voltage Vout can be set to a voltage value corresponding to the first predetermined grayscale. The microcontroller 202 can supply the sensing data Sdataa generated using the output voltage Vout corresponding to the first predetermined grayscale to the timing controller 11a.

[0236] When the second control switch SWcb is turned on, the sink current Isa can be set to a current value corresponding to the second predetermined grayscale, and thus the output voltage Vout can be set to a voltage value corresponding to the second predetermined grayscale. The microcontroller 202 can supply the sensing data Sdataa generated using the output voltage Vout corresponding to the second predetermined grayscale to the timing controller 11a.

[0237] When the third control switch SWcc is turned on, the sink current Isa can be set to a current value corresponding to the third predetermined grayscale, and thus the output voltage Vout can be set to a voltage value corresponding to the third predetermined grayscale. The microcontroller 202 can supply the sensing data Sdataa generated using the output voltage Vout corresponding to the third predetermined grayscale to the timing controller 11a.

[0238] That is to say, Fig.13 In the sensing channel shown in FIG. 1 , sensing data Sdataa corresponding to a plurality of grays may be generated during a sensing period. The timing controller 11a may generate data values ​​corresponding to the remaining grays using the sensing data Sdataa corresponding to the plurality of grays. When data values ​​are generated using the sensing data Sdataa corresponding to the plurality of grays, more reliable data values ​​may be generated compared to a case where data values ​​are generated using the sensing data Sdataa corresponding to one gray.

[0239] Although the present disclosure has been described with reference to the embodiments thereof, it will be understood by those skilled in the art that various modifications and changes may be made to the present disclosure within the scope without departing from the spirit and scope of the present disclosure described in the claims.

Claims

1. A sensing unit, comprising: a sensing line, receiving a pixel current from a pixel; a current sink unit connected to the sensing line and receiving a sink current from the sensing line; as well as a current integrator connected to the sensing line and generating an output voltage using a control current supplied from the sensing line, The current injection unit changes the current amount of the injection current in response to the output voltage.

2. The sensing unit according to claim 1, wherein: The control current corresponds to a difference between the pixel current and the sink current.

3. The sensing unit according to claim 1, wherein: When the pixel current is greater than the sink current, the output voltage decreases, and the current sink unit increases the sink current in response to the output voltage.

4. The sensing unit according to claim 1, wherein: When the pixel current is less than the sink current, the output voltage increases, and the current sink unit reduces the sink current in response to the output voltage.

5. The sensing unit according to claim 1, wherein: When the pixel current and the sink current are the same, the output voltage maintains a constant voltage.

6. The sensing unit according to claim 5, further comprising: A voltage storage unit, storing the output voltage; as well as An analog-to-digital converter generates sensing data using the output voltage stored in the voltage storage unit.

7. The sensing unit according to claim 6, wherein: The voltage storage unit comprises: an input switch and an output switch connected in series between an output terminal of the current integrator and the analog-to-digital converter; and A holding capacitor is connected between a common terminal of the input switch and the output switch and a ground.

8. The sensing unit according to claim 1, wherein: The current integrator comprises: an operational amplifier having an inverting input terminal connected to the sensing line and a non-inverting input terminal receiving a voltage of a reference power supply; a feedback capacitor connected between the inverting input terminal and an output terminal of the operational amplifier; and A reset switch is connected in parallel with the feedback capacitor between the inverting input terminal and the output terminal of the operational amplifier.

9. The sensing unit according to claim 1, further comprising: a first switch connected between the sensing line and the current integrator; as well as The second switch is connected between a common node between the first switch and the current integrator and the current sink unit.

10. The sensing unit according to claim 1, further comprising: A current source unit is connected to the sensing line and is configured to supply a source current to the sensing line.

11. The sensing unit according to claim 10, wherein: The current source unit controls a current amount of the source current in response to the output voltage.

12. The sensing unit according to claim 10, wherein: The control current corresponds to a value obtained by subtracting the sink current from a sum of the pixel current and the source current.

13. A display device, comprising: Pixels, connected to scan lines, data lines, and sense lines; a data driver configured to supply a data signal to the data line during a display period and to supply a reference data signal to the data line during a sensing period; a sensing unit connected to the sensing line and configured to generate sensing data during the sensing period; as well as a timing controller configured to receive input data and control output data supplied to the data driver in response to the sensing data, Wherein, the sensing channel of the sensing unit includes: a current sink unit connected to the sensing line receiving a pixel current from the pixel in response to the reference data signal and receiving a sink current from the sensing line; and a current integrator connected to the sensing line and generating an output voltage using a control current supplied from the sensing line, The current sinking unit changes the amount of the sinking current in response to the output voltage.

14. The display device according to claim 13, wherein: The control current corresponds to a difference between the pixel current and the sink current.

15. The display device according to claim 13, wherein: When the pixel current is greater than the sink current, the output voltage decreases, and the current sink unit increases the sink current in response to the output voltage.

16. The display device according to claim 13, wherein: When the pixel current is less than the sink current, the output voltage increases, and the current sink unit reduces the sink current in response to the output voltage.

17. The display device according to claim 13, wherein: When the pixel current and the sink current are the same, the output voltage maintains a constant voltage.

18. The display device according to claim 17, wherein: The sensing channel further comprises: a voltage storage unit for storing the output voltage; and An analog-to-digital converter generates the sensing data using the output voltage stored in the voltage storage unit.

19. The display device according to claim 18, wherein: The analog-to-digital converter is connected to a plurality of the sensing channels.

20. The display device according to claim 18, wherein: The voltage storage unit comprises: an input switch and an output switch connected in series between an output terminal of the current integrator and the analog-to-digital converter; and A holding capacitor is connected between a common terminal of the input switch and the output switch and a ground.

21. The display device according to claim 13, wherein: The current integrator comprises: an operational amplifier having an inverting input terminal connected to the sensing line and a non-inverting input terminal receiving a voltage of a reference power supply; a feedback capacitor connected between the inverting input terminal and an output terminal of the operational amplifier; and A reset switch is connected in parallel with the feedback capacitor between the inverting input terminal and the output terminal of the operational amplifier.

22. The display device according to claim 13, wherein: The sensing channel further comprises: A first switch connected between the sensing line and the current integrator; and The second switch is connected between a common node between the first switch and the current integrator and the current sink unit.

23. The display device according to claim 13, wherein: The sensing channel further comprises: A current source unit is connected to the sensing line and is configured to supply a source current to the sensing line.

24. The display device according to claim 23, wherein: The current source unit controls a current amount of the source current in response to the output voltage.

25. The display device according to claim 23, wherein: The control current corresponds to a value obtained by subtracting the sink current from a sum of the pixel current and the source current.

26. A display device comprising: A pixel unit, comprising a plurality of pixels; a data driver connected to the pixels via data lines; as well as A sensing unit connected to the pixel through a sensing line, Wherein, the sensing channel of the sensing unit includes: a current sink unit connected to the sensing line receiving the pixel current from the pixel and receiving a sink current from the sensing line; and a current integrator connected to the sensing line and generating an output voltage using a control current supplied from the sensing line, The data driver supplies a voltage of a data signal corresponding to the output voltage of the current integrator to the pixel via the data line.

27. The display device according to claim 26, wherein: The data driver supplies the output voltage as the voltage of the data signal to the data line.

28. The display device according to claim 26, wherein: The control current corresponds to a difference between the pixel current and the sink current.

29. The display device according to claim 26, wherein: The pixel current is changed in response to the output voltage of the current integrator.

30. The display device according to claim 29, wherein: When the pixel current is greater than the sink current, the output voltage decreases, and the pixel current decreases in response to the decrease in the output voltage.

31. The display device according to claim 29, wherein: When the pixel current is less than the sink current, the output voltage increases, and the pixel current increases in response to the increase in the output voltage.

32. The display device according to claim 29, wherein: When the pixel current and the sink current are the same, the output voltage maintains a constant voltage, and the pixel current is also maintained constant in response to the constant output voltage.

33. The display device according to claim 26, further comprising: An analog-to-digital converter generates sensing data using the output voltage.

34. The display device according to claim 33, wherein: The sink current corresponds to a pixel current that needs to flow to the pixel when the pixel is driven at a predetermined grayscale, and The sensing data corresponds to output data of the pixel corresponding to the predetermined grayscale.

35. The display device according to claim 34, further comprising: A timing controller generates output data corresponding to remaining grayscales except the predetermined grayscale in response to the sensing data.

36. The display device according to claim 35, further comprising: A determiner is connected to the analog-to-digital converter and is configured to supply a control signal to the timing controller when the sensing data maintains the same value during a predetermined time.

37. The display device according to claim 26, wherein: The current integrator comprises: an operational amplifier having an inverting input terminal connected to the sensing line and a non-inverting input terminal receiving a voltage of a reference power supply; a feedback capacitor connected between the inverting input terminal and an output terminal of the operational amplifier; and A reset switch is connected in parallel with the feedback capacitor between the inverting input terminal and the output terminal of the operational amplifier.

38. The display device according to claim 26, further comprising: A first switch connected between the pixel and the current integrator; as well as The second switch is connected between the current integrator and the current injection unit.

39. The display device according to claim 26, wherein: The data driver comprises: a signal generator, configured to supply the data signal to the data line; a buffer connected between the signal generator and the data line; a first input switch connected between the buffer and the current integrator; and The second input switch is connected between the buffer and the signal generator.

40. The display device according to claim 26, wherein: The current injection unit comprises: at least two current sources; and a control switch connected between each of the current sources and the sensing line, and Wherein, the on-times of the control switches do not overlap.

41. The display device according to claim 40, wherein: Each of the at least two current sources receives the sink current having a different current amount from the sensing line.

42. The display device according to claim 26, further comprising: a digital buffer receiving the output voltage from the current integrator; as well as a microcontroller for generating sensing data using an output value of the digital buffer; The data driver generates the voltage of the data signal corresponding to the output voltage using the sensing data.

43. The display device according to claim 42, wherein: The sink current corresponds to a pixel current that needs to flow to the pixel when the pixel is driven at a predetermined grayscale, and The sensing data corresponds to output data of the pixel corresponding to the predetermined grayscale.

44. The display device according to claim 43, further comprising: A timing controller generates output data corresponding to remaining grayscales except the predetermined grayscale in response to the sensing data.

45. The display device according to claim 44, further comprising: A determiner is connected to the microcontroller and is configured to supply a control signal to the timing controller when the sensing data maintains the same value during a predetermined time.

46. ​​A display device comprising: Pixels; a data driver connected to the pixels via data lines; a timing controller for supplying output data to the data driver in response to compensation data; as well as a sensing unit connected to the pixel via a sensing line and including a current integrator generating an output voltage using a control current supplied from the pixel, Wherein, when the output voltage maintains a constant value during a predetermined time, sensing data generated in response to the output voltage is stored in the timing controller as the compensation data.

47. The display device according to claim 46, further comprising: an analog-to-digital converter, generating the sensing data using the output voltage of the current integrator; as well as A determiner is connected to the analog-to-digital converter and is configured to supply a control signal to the timing controller when the sensing data maintains a constant value during the predetermined time.

48. The display device according to claim 46, further comprising: a digital buffer receiving the output voltage from the current integrator; a microcontroller, generating the sensing data using the output value of the digital buffer; as well as A determiner is connected to the microcontroller and is configured to supply a control signal to the timing controller when the sensing data maintains a constant value during the predetermined time.

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