KR20180076467A - Pixel sensing apparatus and panel driving apparatus - Google Patents

Abstract

The present invention relates to a technology for compensating for a deviation existing between individual channel circuits in a pixel sensing apparatus. The technology provides a two-point sensing method for compensating for a sensing offset value through a zero sensing mode and compensating for a sensing gain value through a maximum sensing mode. The pixel sensing apparatus comprises a plurality of channel circuits and a data transfer unit.

Description

Technical Field [0001] The present invention relates to a pixel sensing device and a panel driving device,

TECHNICAL FIELD The present invention relates to a technique for driving a display device.

The display device includes a source driver for driving pixels arranged on the panel.

The source driver determines the data voltage according to the image data, and supplies the data voltages to the pixels to control the brightness of each pixel.

On the other hand, even if the same data voltage is supplied, the brightness of each pixel may vary depending on the characteristics of the pixels. For example, a pixel includes a driving transistor. If the threshold voltage of the driving transistor is changed, the brightness of the pixel is different even if the same data voltage is supplied. If the source driver does not consider a change in the characteristics of these pixels, the pixels may be driven with an undesired brightness and the image quality may be degraded.

Specifically, the characteristics of pixels vary with time or depending on the surrounding environment. At this time, if the source driver supplies the data voltage without considering the changed characteristics of the pixels, there occurs a problem that the image quality is degraded (for example, a problem such as screen unevenness).

In order to solve this problem of image degradation, the display device may include a pixel sensing device for sensing the characteristics of the pixels.

The pixel sensing device may receive an analog signal for each pixel through a sensing line connected to each pixel. The pixel sensing device converts an analog signal into pixel sensing data and transmits the pixel sensing data to the timing controller. The timing controller recognizes the characteristics of each pixel through the pixel sensing data. Then, the timing controller compensates the image data by reflecting the characteristics of each pixel, thereby making it possible to improve the image quality degradation due to the pixel deviation.

On the other hand, the pixel sensing device may include a plurality of channel circuits for measuring within a short time a number of pixels arranged on the panel, for example, several thousand or more pixels. However, such a large number of channel circuits have a problem of lowering the accuracy of sensing due to variations in the manufacturing process or the surrounding environment.

In view of the foregoing, it is an object of the present invention to provide a technique for compensating for a deviation existing between channel circuits of a pixel sensing device.

According to an aspect of the present invention, there is provided an apparatus for sensing characteristics of a plurality of pixels disposed on a display panel, the apparatus comprising: an analog-to-digital converter for pre- An analog-digital-conversion unit for converting an output signal of the analog front end into digital data, and a test source unit for supplying a test analog signal to the analog front end through the input end A plurality of channel circuits; And a data transfer unit for transferring the digital data to a data processing circuit for compensating image data according to characteristics of the pixel, wherein the test source unit included in the plurality of channel circuits is a zero-signal sensing mode ) Simultaneously supplies the test analog signal to the input terminal so that the input of the analog front end becomes a zero level, and the data processing circuit supplies the test analog signal to the input terminal using the digital data received in the zero- The pixel sensing device compensates the sensing offset value of the pixel.

According to another aspect of the present invention, there is provided an apparatus for driving a panel in which a plurality of data lines and a plurality of sensing lines are arranged, the plurality of pixels being arranged and connected to the pixels, To a data driving circuit; A data processing circuit for compensating the image data using pixel sensing data corresponding to the characteristics of the pixel; And an analog front end included in the plurality of channel circuits, and converts an output signal of the analog front end into the pixel sensing data and transmits the pixel sensing data to the data processing circuit. A test analog signal is supplied to the analog front end so that the input of the analog front end becomes a zero level in a zero-signal sensing mode in order to eliminate a deviation of a sensing gain value and a sensing offset value of the analog front end And a pixel sensing circuit in which the test analog signal having a preset maximum level in a maximum-signal sensing mode is supplied to the analog front end.

According to another aspect of the present invention, there is provided an apparatus for sensing characteristics of a plurality of pixels arranged on a display panel, comprising: an analog front-end unit for pre-processing an analog signal transmitted from the pixel to an input terminal; A plurality of channel circuits including an analog-digital-conversion unit for converting an output signal of the analog front end into digital data, and a test source unit for supplying a test analog signal to the analog front end through the input end; A memory for storing the digital data; A deviation compensator which analyzes the deviation of the channel circuit using the digital data stored in the memory and compensates the digital data according to a deviation of the analyzed channel circuit; And a data transfer unit for transferring the digital data compensated by the data processing circuit for compensating the image data according to the characteristics of the pixel.

As described above, according to the present invention, the deviation existing between the channel circuits of the pixel sensing device can be compensated.

1 is a configuration diagram of a display device according to an embodiment.
FIG. 2 is a view showing a structure of each pixel of FIG. 1 and a signal inputted / outputted to / from a pixel in a data driving circuit and a pixel sensing circuit.
3 is a diagram showing an internal configuration of a pixel sensing circuit and a data processing circuit according to an embodiment.
4 is a view illustrating a deviation compensation process according to an embodiment.
5 is an internal configuration diagram of a test source unit according to an embodiment.
6 is a diagram showing an example in which a level shifter is further included in the analog front end portion of the channel circuit.
7 is a diagram showing an example of proceeding to a maximum value sensing mode using an external test source device.
8 is a flowchart of a panel driving method according to an embodiment.
9 is a diagram showing an internal configuration of a pixel sensing circuit according to another embodiment.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that, in adding reference numerals to the constituent elements of the drawings, the same constituent elements are denoted by the same reference symbols as possible even if they are shown in different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

In describing the components of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are intended to distinguish the constituent elements from other constituent elements, and the terms do not limit the nature, order or order of the constituent elements. When a component is described as being "connected", "coupled", or "connected" to another component, the component may be directly connected to or connected to the other component, It should be understood that an element may be "connected," "coupled," or "connected."

1 is a configuration diagram of a display device according to an embodiment.

Referring to FIG. 1, a display apparatus 100 may include a panel driving apparatus 120, 130, 140, 150 for driving a panel 110 and a panel 110.

A plurality of data lines DL, a plurality of gate lines GL and a plurality of sensing lines SL may be disposed in the panel 110 and a plurality of pixels P may be disposed.

The devices 120, 130, 140, and 150 that drive at least one configuration included in the panel 110 may be referred to as a panel drive. For example, the data driving circuit 120, the pixel sensing circuit 130, the gate driving circuit 140, the data processing circuit 150, and the like may be referred to as panel driving devices.

Each of the circuits 120, 130, 140, and 150 described above may be referred to as a panel drive, and the whole or a plurality of circuits may be referred to as a panel drive.

In the panel driving apparatus, the gate driving circuit 140 can supply a scan signal of a turn-on voltage or a turn-off voltage to the gate line GL. When a scan signal of a turn-on voltage is supplied to the pixel P, the pixel P is connected to the data line DL, and when a scan signal of a turn- DL) is released.

In the panel driving apparatus, the data driving circuit 120 supplies the data voltage to the data line DL. The data voltage supplied to the data line DL is transferred to the pixel P connected to the data line DL according to the scan signal.

In the panel driving apparatus, the pixel sensing circuit 130 receives an analog signal (e.g., voltage, current, etc.) formed in each pixel P. The pixel sensing circuit 130 may be connected to each pixel P according to a scan signal or may be connected to each pixel P according to a separate sensing signal. At this time, a separate sensing signal may be generated by the gate driving circuit 140.

In the panel driving apparatus, the data processing circuit 150 can supply various control signals to the gate driving circuit 140 and the data driving circuit 120. The data processing circuit 150 may generate a gate control signal (GCS) to start the scan in accordance with the timing to be implemented in each frame, and may transmit the gate control signal to the gate driving circuit 140. The data processing circuit 150 can output the video data (RGB) obtained by converting the externally input video data according to the data signal format used by the data driving circuit 120 to the data driving circuit 120. The data processing circuit 150 may transmit a data control signal DCS for controlling the data driving circuit 120 to supply the data voltage to each pixel P in accordance with each timing.

The data processing circuit 150 can compensate and transmit the image data RGB according to the characteristics of the pixel P. [ At this time, the data processing circuit 150 may receive the pixel sensing data S_DATA from the pixel sensing circuit 130. The pixel sensing data S_DATA may include a measurement value for the characteristic of the pixel P. [

On the other hand, the data driving circuit 120 may be called a source driver. The gate drive circuit 140 may be called a gate driver. The data processing circuit 150 may be called a timing controller. The data driving circuit 120 and the pixel sensing circuit 130 may be included in one integrated circuit 125 and may be referred to as a source driver IC (Integrated Circuit). The data driving circuit 120, the pixel sensing circuit 130, and the data processing circuit 150 are included in one integrated circuit, and may be called integrated ICs. Although the present embodiment is not limited to this name, descriptions of some components generally known in a source driver, a gate driver, a timing controller and the like are omitted in the following description of the embodiments. Therefore, in understanding the embodiment, it should be considered that some of these configurations are omitted.

Meanwhile, the panel 110 may be an organic light emitting display panel. At this time, the pixels P disposed on the panel 110 may include an organic light emitting diode (OLED) and one or more transistors. The characteristics of the organic light emitting diode (OLED) and the transistor included in each pixel P may vary depending on time or the surrounding environment. The pixel sensing circuit 130 according to an exemplary embodiment may sense characteristics of the components included in each pixel P and transmit the sensed characteristics to the data processing circuit 150.

FIG. 2 is a view showing a structure of each pixel of FIG. 1 and a signal inputted / outputted to / from a pixel in a data driving circuit and a pixel sensing circuit.

2, the pixel P may include an organic light emitting diode (OLED), a driving transistor DRT, a switching transistor SWT, a sensing transistor SENT, and a storage capacitor Cstg.

The organic light emitting diode (OLED) may include an anode electrode, an organic layer, and a cathode electrode. Under the control of the driving transistor DRT, the anode electrode is connected to the driving voltage EVDD and the cathode electrode is connected to the ground voltage EVSS.

The driving transistor DRT can control the brightness of the organic light emitting diode OLED by controlling the driving current supplied to the organic light emitting diode OLED.

The first node N1 of the driving transistor DRT may be electrically connected to the anode electrode of the organic light emitting diode OLED and may be a source node or a drain node. The second node N2 of the driving transistor DRT may be electrically connected to the source node or the drain node of the switching transistor SWT and may be a gate node. The third node N3 of the driving transistor DRT may be electrically connected to the driving voltage line DVL for supplying the driving voltage EVDD and may be a drain node or a source node.

The switching transistor SWT is electrically connected between the data line DL and the second node N2 of the driving transistor DRT and can be turned on by receiving a scan signal through the gate lines GL1 and GL2.

When the switching transistor SWT is turned on, the data voltage Vdata supplied from the data driving circuit 120 through the data line DL is transferred to the second node N2 of the driving transistor DRT.

The storage capacitor Cstg may be electrically connected between the first node N1 and the second node N2 of the driving transistor DRT.

The storage capacitor Cstg may be a parasitic capacitor existing between the first node N1 and the second node N2 of the driving transistor DRT and may be an external capacitor deliberately designed outside the driving transistor DRT .

The sensing transistor SENT connects the first node N1 of the driving transistor DRT and the sensing line SL and the sensing line SL transmits the reference voltage Vref to the first node N1, For example, a voltage or a current, to the pixel sensing circuit 130, which is formed at the node N1.

The pixel sensing circuit 130 measures the characteristics of the pixel P using an analog signal Vsense or Isense transmitted through the sensing line SL.

When the voltage of the first node N1 is measured, the threshold voltage, mobility, current characteristics, and the like of the driving transistor DRT can be grasped. Further, by measuring the voltage of the first node N1, the degree of deterioration of the organic light emitting diode OLED such as parasitic capacitance and current characteristics of the organic light emitting diode OLED can be grasped.

The pixel sensing circuit 130 may measure the voltage of the first node N1 and transmit the measured value to the data processing circuit 150 (see FIG. 1). Then, the data processing circuit (see 150 in FIG. 1) can analyze the voltage of the first node N1 to grasp the characteristics of each pixel P.

3 is a diagram showing an internal configuration of a pixel sensing circuit and a data processing circuit according to an embodiment.

Referring to FIG. 3, a plurality of pixels P may be disposed on the panel 110. The pixel sensing circuit 130 may include a plurality of channel circuits 310 for sensing a plurality of pixels P, a data transfer unit 320, and the like. The data processing circuit 150 may include a data receiving unit 330, a sensing data compensating unit 340, an image data processing unit 350, and the like.

Each channel circuit 310 includes an analog front-end (AFE) unit 312, an analog-digital-conversion (ADC) unit 314, a test source unit 316, can do.

The analog front end 312 may pre-process an analog signal transmitted from the pixel P to the input T.

The analog front end 312 may include an integrator 313. The integrator 313 is connected in parallel with a capacitor Ci and a capacitor Ci connected between one input terminal of the amplifier Ap and the other input terminal of the amplifier Ap, A reset switch Sr and the like.

When the analog signal is a voltage signal, the analog signal can be directly transmitted to the analog-to-digital converter 314 while the reset switch Sr of the integrator 313 is kept turned on.

Or the reset switch Sr is kept turned off and the difference between the analog signal input to one input terminal of the amplifier Ap and the reference voltage Vr input to the other input terminal is amplified by the amplifier Ap Amplified and transmitted to the analog-to-digital converter 314.

When the analog signal is a current signal, the current signal is integrated through the capacitor Ci, and the integrated value of the current signal can be transmitted to the analog-to-digital converter 314. The value integrated in the capacitor Ci can be reset by the reset switch Sr in the next measurement.

The analog-to-digital converter 314 can convert the output signal of the analog front end 312 into digital data.

The data transmission unit 320 may transmit the digital data transmitted from the analog-to-digital conversion unit 314 to the outside, for example, the data processing circuit 150 -.

Since many pixels P are arranged on the panel 110, a plurality of channel circuits 310 may be included in the pixel sensing circuit 130 to sense the many pixels P in a short time. Each channel circuit 310 shortens the sensing time for all the pixels P by simultaneously sensing at least one pixel P arranged in the panel 110 in parallel.

Incidentally, since a plurality of channel circuits 310 are included in the pixel sensing device 130, there may arise a problem that a deviation occurs between the channel circuits 310.

For example, in the integrator 313 included in the analog front end 312, the amplifier Ap may cause a deviation of the gain value and the offset value between the channel circuits 310. Also, in the integrator 313, the capacitor Ci can cause a capacitance deviation between the channel circuits 310. The deviation of the capacitance results in a deviation of the denominator value from the integral value of the current signal, And a gain value deviation between the first and second output terminals 310 and 310 is generated. In addition, although the detailed configuration is not illustrated, the configurations included in the analog-to-digital converter 314 may also cause a deviation of the gain value and the offset value between the channel circuits 310. [

Each channel circuit 310 may include a test source portion 316 to compensate for such channel circuit 310 deviations. The test source unit 316 may supply the test analog signal to the analog front end 312 via the input T. [

Then, the data processing circuit 150 can compensate for the deviation of the channel circuit 310 (for example, the deviation of the sensing offset value or the deviation of the sensing gain value) by using the digital data generated by the test analog signal.

The data receiving unit 330 of the data processing circuit 150 receives the digital data-pixel sensing data S_DATA- transmitted from the data transmitting unit 320 and the sensing data compensating unit 340 receives the received pixel sensing data S_DATA) can be used to compensate for the deviation of each channel circuit 310.

The sensing data compensating unit 340 compensates the pixel sensing data S_DATA transmitted after the deviation compensation for each channel circuit 310 is completed, for example, a sensing offset compensation value or a sensing gain compensation value - to the image data processing unit 350. [0050]

The image data processing unit 350 can recognize the characteristics of each pixel P by using the compensated pixel sensing data and compensate the image data according to the characteristics of each pixel P. [

4 is a view illustrating a deviation compensation process according to an embodiment.

The pixel sensing circuit and the data processing circuit can compensate for the deviation of the channel circuit through two-point sensing. Here, 2 points may be a zero point and a maximum point. The pixel sensing circuit and the data processing circuit can compensate the sensing offset value and the sensing gain value by sensing the zero point and the maximum point. As a specific example, the pixel sensing circuit and the data processing circuit can compensate the sensing offset value through sensing at the zero point and compensate the sensing gain value through sensing at the maximum point.

3 and 4, the test source portion 316 included in each channel circuit 310 may be configured such that the input of the analog front end 312 in the zero-signal sensing mode is at a zero level zero level) to the input terminal T at the same time.

If there is no sensing offset in the channel circuit 310, the digital data-pixel sensing data S_DATA - generated according to the zero level input to the analog front end 312 may have a zero value. However, when there is a sensing offset in the channel circuit 310, the digital data-pixel sensing data S_DATA - generated according to the zero level input to the analog front end 312 has a sensing offset value like the A point .

The data processing circuit 150, for example, the sensing data compensator 340, may compensate the sensing offset value of the channel circuit 310 using the pixel sensing data S_DATA received in the zero sensing mode. For example, the sensing data compensator 340 stores a measurement value included in the pixel sensing data S_DATA received in the zero-point sensing mode, and subtracts the measured value from the received pixel sensing data S_DATA The sensing offset value of each channel circuit 310 can be compensated.

Conceptually, in FIG. 4, the pixel sensing data before the sensing offset value is compensated can be shown as a first curve LN1. When the sensing offset value is compensated through the zero sensing mode, Can be shown as a curve such that the starting point becomes a zero point B like the curve LN2.

3 and 4, the test source unit 316 included in each of the channel circuits 310 may be a test analog unit having a predetermined maximum level in a maximum-signal sensing mode, Signals can be supplied to the input terminal T at the same time.

Then, the data processing circuit 150 (for example, the sensing data compensating unit 340) calculates the sensing gain of the channel circuit 310 using the digital data-pixel sensing data S_DATA - received in the maximum value sensing mode The value can be compensated.

In the maximum value sensing mode, the pixel sensing data S_DATA before the sensing gain value is compensated represents the point C. The sensing data compensating unit 340 compensates the pixel sensing data S_DATA according to the preset setting in the maximum value sensing mode, It is possible to calculate the compensation value for the sensing gain according to the relationship between the point C and the point D.

[Equation 1]

Y '= (Y - Ya) x Yd / Yc

Y is the pre-compensation pixel sensing data, Y 'is the compensated pixel sensing data, Ya is the sensing offset compensation value as the pre-compensation pixel sensing data in the zero-point sensing mode, Yc is the sensing offset compensation value, Yd is pixel sensing data previously stored corresponding to the test analog signal at the maximum level in the maximum value sensing mode, and Yd / Yc is a sensing gain compensation value.

The data processing circuit 150 (for example, the sensing data compensator 340) may generate the complementary expression (1) using the pixel sensing data obtained in the zero sensing mode and the maximum sensing mode.

3, when the test source part 316 is included in each of the channel circuits 310, the deviation of each channel circuit 310 can be corrected accurately by the deviation of the test source part 316 A problem that can not be compensated can occur. For example, the test analog signal itself output from the test source unit 316 may have a deviation between the channel circuits 310. [

However, if the pixel sensing circuit 130 and the data processing circuit 150 compensate the sensing offset value in the zero-point sensing mode as in the above-described embodiment, the deviation in the test source unit 316 is not reflected, So that the deviation of the circuit 310 can be compensated. Referring to FIG. 5, an embodiment in which the deviation of the test source unit 316 is not reflected in the zero-point sensing mode will be described.

5 is an internal configuration diagram of a test source unit according to an embodiment.

3, 4, and 5, the test source portion 316 may include a variable current source 510, a variable voltage source 520, and three switches S1, S2, S3, have.

When the test analog signal is a current signal, the test source unit 316 turns off the first switch S1 connecting the variable current source 510 and the input terminal T, It is possible to prevent the current from flowing to the first electrode 312. When the zero-level test analog signal is generated by the switch-off method, no deviation occurs between the test analog signals of the respective channel circuits 310.

When the test analog signal is a voltage signal, the test source unit 316 turns off the second switch S2 connecting the variable voltage source 520 and the input terminal T and outputs the reference voltage Vr and the input terminal T, The third switch S3 may be turned on. In this way, the same reference voltage Vr is supplied to one input terminal of the amplifier Ap and the other input terminal, and the input of the analog front end 312 can be a zero level.

On the other hand, when the test analog signal is the current signal, in the maximum value sensing mode, the first switch S1 is turned on and the test analog signal having the maximum value level in the variable current source 510 according to the preset value is input to the input terminal T ). ≪ / RTI >

When the test analog signal is a voltage signal, in the maximum value sensing mode, the second switch S2 is turned on and the test analog signal having the maximum value level in the variable voltage source 520 according to the preset value is input to the input terminal T ). ≪ / RTI >

In the zero sensing mode, the deviation of the test source part 316 in each channel circuit 310 is not reflected, but in the maximum value sensing mode, the deviation of the test source part 316 in each channel circuit 310 is reflected . At this time, if the signal level magnitude of the test analog signal in the maximum value sensing mode is increased, the influence of the deviation of the test source portion 316 in each channel circuit 310 can be reduced. However, if the magnitude of the signal level of the test analog signal becomes large, the signal - the output signal of the analog front end 312 formed at the output terminal of the analog front end 312 may deviate from the input range of the analog digital converter 314 .

To solve this problem, the analog front end may further include a level shifter connected between the integrator 313 and the analog-to-digital converter 314.

6 is a diagram showing an example in which a level shifter is further included in the analog front end portion of the channel circuit.

6, the channel circuit 610 may further include a level shifter 618 connected between the integrator 313 and the analog-to-digital converter 314 at the analog front end 612.

In the maximum value sensing mode, the test source unit 316 may output a test analog signal having a maximum level. A signal formed at the output terminal of the integrator 313 may deviate from the input range of the analog-to-digital converter 314 by the test analog signal having the maximum level.

The level shifter 618 can reduce the signal formed at the output terminal of the integrator 313 to the input range of the analog-to-digital converter 314.

On the other hand, in the maximum value sensing mode, an external test source device can be used to supply the same external test analog signal to all the channel circuits in order to eliminate the influence of the deviation occurring in the test source section 316 of each channel circuit.

7 is a diagram showing an example of proceeding to a maximum value sensing mode using an external test source device.

Referring to FIG. 7, one external test source device 740 may be connected to the analog front end 312 of the plurality of channel circuits 710 at the input T of the maximum value sensing mode.

The external test source device 740 can sequentially supply an external test analog signal having a preset maximum level in the maximum value sensing mode to the input terminal T of each channel circuit 710.

Since the same external test analog signal is supplied to the plurality of channel circuits 710 through one external test source device 740, a sensing error does not occur according to the deviation of the test analog signal. The zero point sensing mode may be performed through the external test source device 740. However, since the sensing through the external test source device 740 can not simultaneously execute a plurality of channel circuits, there is a problem that the sensing speed is slowed down. Accordingly, a method may be applied in which the zero sensing mode is run through the test source unit 716 and the maximum value sensing mode is run through the external test source device 740 in an eclectic manner.

8 is a flowchart of a panel driving method according to an embodiment.

A display device to which the panel driving method is applied may include a panel, a data driving circuit, a data processing circuit, a pixel sensing circuit, and the like.

A plurality of data lines and a plurality of sensing lines may be arranged in the panel, in which a plurality of pixels are arranged and connected to the pixels.

The data driving circuit converts the image data into a data voltage and supplies the data voltage to the data line, and the data processing circuit can compensate the image data using the pixel sensing data corresponding to the characteristics of the pixel.

The pixel sensing circuit may pre-process an analog signal transmitted from the sensing line through the analog front end included in the plurality of channel circuits, convert the output signal of the analog front end into pixel sensing data, and transmit the pixel sensing data to the data processing circuit. At this time, a deviation may occur between the respective channel circuits. The panel driving method according to an embodiment can compensate a deviation occurring between each channel circuit through 2-point sensing.

First, the pixel sensing circuit can supply a test analog signal to the analog front end so that the input of the analog front end becomes zero level in the zero sensing mode (S800). The data processing circuit can compensate the sensing offset value of the channel circuit using the first pixel sensing data received in the zero sensing mode.

Then, the pixel sensing circuit can supply a test analog signal having a preset maximum level in the maximum value sensing mode to the analog front end (S802). And, the data processing circuit can compensate the sensing gain value of the channel circuit by using the second pixel sensing data received in the maximum value sensing mode.

When compensation is made for the sensing offset value and the sensing gain value, the data processing circuit can compensate the received pixel sensing data using the sensing offset value and the sensing gain value (S804).

Then, the data processing circuit can grasp the characteristics of each pixel by using the compensated pixel sensing data. The characteristic data of each pixel can be stored in the form of a look-up table.

Then, the data processing circuit can compensate the image data using a lookup table corresponding to the characteristic of each pixel (S806). Then, the compensated image data can be transmitted to the data driving circuit.

Then, the data driving circuit generates a data voltage according to the compensated image data, and drives the data line connected to each pixel (S808).

Meanwhile, the data processing circuit can transmit a mode signal indicating a zero sensing mode or a maximum value sensing mode to the pixel sensing circuit. Depending on the mode signal, the pixel sensing circuit may operate in a zero sensing mode or in a maximum sensing mode.

Alternatively, the pixel sensing circuit may operate in a zero sensing mode or a maximum sensing mode without a mode signal, and may include mode information indicating a zero sensing mode or a maximum sensing mode in the pixel sensing data. The data processing circuit can recognize the mode applied to the pixel sensing data using the mode information.

In the pixel sensing circuit, only the digital data sensing each pixel and the compensation for the digital data-pixel sensing data can be performed in the data processing circuit. However, in some embodiments, the pixel sensing circuit may perform compensation for the digital data and transmit the compensated pixel sensing data to the data processing circuitry.

9 is a diagram showing an internal configuration of a pixel sensing circuit according to another embodiment.

9, the pixel sensing circuit 930 may include a plurality of channel circuits 310, a memory 922, a deviation compensating unit 924, a data transmitting unit 320, and the like.

Each channel circuit 310 may include an analog front end 312, an analog-to-digital converter 314, a test source 316, and the like.

The analog front end 312 may pre-process an analog signal transmitted from the pixel P to the input T. The analog-to-digital converter 314 can convert the output signal of the analog front end 312 into digital data. The test source unit 316 may supply the test analog signal to the analog front end 312 via the input terminal T. [

The memory 922 may store digital data output from each of the channel circuits 310.

The deviation compensating unit 922 may analyze the deviation of the channel circuit 310 using the digital data stored in the memory 922 and compensate the digital data according to the deviation of the analyzed channel circuit 310. [

The data transfer unit 320 may transmit the compensated digital data-pixel sensing data (S_DATA) to the data processing circuit for compensating the image data according to the characteristics of the pixels.

The test source unit 316 included in the plurality of channel circuits 310 in the pixel sensing circuit 930 can simultaneously supply a test analog signal having a zero level in the zero point sensing mode to the input terminal T . The deviation compensating unit 924 can compensate the sensing offset value of the channel circuit 310 using the digital data stored in the memory 922 in the zero point sensing mode.

In this pixel sensing circuit 930, the test source unit 316 included in the plurality of channel circuits 310 simultaneously supplies the test analog signal having the preset maximum level in the maximum value sensing mode to the input terminal T . The deviation compensating unit 924 can compensate the sensing gain value of the channel circuit 310 using the digital data stored in the memory 922 in the maximum value sensing mode.

According to the embodiments described above, the deviation existing between the channel circuits of the pixel sensing device can be compensated. According to this embodiment, it is possible to quickly and accurately compensate the sensing offset value and the sensing gain value according to the two-point sensing method. According to this embodiment, it is possible to compensate the sensing offset value of each channel circuit without being influenced by the deviation of the test analog signal applied to each channel circuit according to the zero point sensing mode.

It is to be understood that the terms "comprises", "comprising", or "having" as used in the foregoing description mean that the constituent element can be implanted unless specifically stated to the contrary, But should be construed as further including other elements. All terms, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, unless otherwise defined. Commonly used terms, such as predefined terms, should be interpreted to be consistent with the contextual meanings of the related art, and are not to be construed as ideal or overly formal, unless expressly defined to the contrary.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

Claims (13)

An apparatus for sensing characteristics of a plurality of pixels arranged in a display panel,
An analog front-end unit for pre-processing an analog signal transmitted from the pixel to an input terminal,
An analog-digital-conversion unit for converting an output signal of the analog front end into digital data,
A plurality of channel circuits including a test source section for supplying a test analog signal to the analog front end section through the input terminal; And
And a data transfer unit for transferring the digital data to a data processing circuit for compensating the image data according to the characteristics of the pixel,
Wherein the test source part included in the plurality of channel circuits simultaneously supplies the test analog signal to the input terminal so that the input of the analog front end part becomes zero level in a zero-signal sensing mode,
Wherein the data processing circuit compensates the sensing offset value of the channel circuit using the digital data received in the zero sensing mode. The method according to claim 1,
Wherein the test source unit included in the plurality of channel circuits simultaneously supplies the test analog signal having a predetermined maximum level in a maximum-signal sensing mode to the input,
Wherein the data processing circuit compensates the sensing gain value of the channel circuit using the digital data in the maximum value sensing mode. 3. The method of claim 2,
Wherein the analog front end includes an amplifier capable of causing a deviation of a gain value and an offset value between the channel circuits and a capacitor connected between one input terminal and an output terminal of the amplifier and having a capacitance deviation between the channel circuits Gt; The method of claim 3,
The signal formed at the output terminal in the maximum value sensing mode is out of the input range of the analog-to-
Wherein the analog front end reduces the signal formed at the output terminal to an input range of the analog-to-digital converter through a level shifter connected between the output terminal and the analog-to-digital converter. The method according to claim 1,
Wherein the analog front end includes an amplifier capable of causing a deviation of a gain value and an offset value between the channel circuits,
Wherein the test source unit supplies the same voltage as one input terminal to one input terminal of the amplifier when the analog signal is a voltage signal. The method according to claim 1,
An external test analog signal having a preset maximum value level in a maximum-signal sensing mode is sequentially supplied from the external test source device to the input terminal of each channel circuit,
Wherein the data processing circuit compensates the sensing gain value of the channel circuit using the digital data in the maximum value sensing mode. An apparatus for driving a panel in which a plurality of pixels are arranged and a plurality of data lines and a plurality of sensing lines are connected to the pixels,
A data driving circuit for converting the image data into a data voltage and supplying the data voltage to the data line;
A data processing circuit for compensating the image data using pixel sensing data corresponding to the characteristics of the pixel; And
And an analog front end unit for pre-processing an analog signal transmitted from the sensing line through an analog front end unit included in the plurality of channel circuits, converting the output signal of the analog front end unit into the pixel sensing data and transmitting the pixel sensing data to the data processing circuit, A test analog signal is supplied to the analog front end so that the input of the analog front end becomes zero level in a zero-signal sensing mode in order to eliminate the deviation of the sensing gain value and the sensing offset value, The test analog signal having a preset maximum level in a maximum-signal sensing mode is supplied to the analog front end of the pixel sensing circuit,
And the panel driving device. 8. The method of claim 7,
The data processing circuit comprising:
The sensing offset value of the channel circuit is compensated by using the first pixel sensing data received in the zero sensing mode and the sensing gain value of the channel circuit is compensated by using the second pixel sensing data received in the maximum sensing mode Compensating panel drive. 8. The method of claim 7,
Wherein the data processing circuit transmits a mode signal indicating the zero sensing mode or the maximum value sensing mode to the pixel sensing circuit. 8. The method of claim 7,
Wherein the pixel sensing circuit includes mode information for indicating the zero sensing mode or the maximum sensing mode to the pixel sensing data. An apparatus for sensing characteristics of a plurality of pixels arranged in a display panel,
An analog front-end unit for pre-processing an analog signal transmitted from the pixel to an input terminal,
An analog-digital-conversion unit for converting an output signal of the analog front end into digital data,
A plurality of channel circuits including a test source section for supplying a test analog signal to the analog front end section through the input terminal;
A memory for storing the digital data;
A deviation compensator which analyzes the deviation of the channel circuit using the digital data stored in the memory and compensates the digital data according to a deviation of the analyzed channel circuit;
A data transfer unit for transferring the digital data compensated by the data processing circuit for compensating the image data according to the characteristics of the pixel,
And the pixel sensing device. 12. The method of claim 11,
Wherein the test source unit included in the plurality of channel circuits simultaneously supplies the test analog signal having a zero level in a zero-signal sensing mode to the input terminal,
Wherein the deviation compensating unit compensates the sensing offset value of the channel circuit using the digital data stored in the memory in the zero point sensing mode. 13. The method of claim 12,
Wherein the test source unit included in the plurality of channel circuits simultaneously supplies the test analog signal having a predetermined maximum level in a maximum-signal sensing mode to the input,
Wherein the deviation compensating unit compensates the sensing gain value of the channel circuit using the digital data stored in the memory in the maximum value sensing mode.

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