WO2017188674A1

WO2017188674A1 - Pixel sensing device and panel driving device

Info

Publication number: WO2017188674A1
Application number: PCT/KR2017/004317
Authority: WO
Inventors: 지승환; 윤정배; 정민영; 최정희
Original assignee: 주식회사 실리콘웍스
Priority date: 2016-04-26
Filing date: 2017-04-24
Publication date: 2017-11-02

Abstract

The present invention provides a pixel sensing device for sensing characteristics of pixels arranged on a display panel, processing and converting the same into valid sensing data, and transmitting the valid sensing data to an external device.

Description

Pixel sensing device and panel driver

The present invention relates to a technique for sensing a characteristic of a pixel disposed in a display panel and a technique for driving such a display panel.

The display device may include a panel driver for controlling the brightness of the pixels disposed in the panel, for example, a driver including a source driver and a timing controller. The panel driver may determine the data voltage according to the image data. In addition, the panel driver may control the brightness of each pixel by supplying the determined data voltage to the pixels.

Meanwhile, even when the same data voltage is supplied, the brightness of each pixel may vary according to the characteristics of the pixels. For example, the pixel may include a driving transistor. When the threshold voltage of the driving transistor is changed, the brightness of the pixel may be changed even though the same data voltage is supplied. If the panel driver does not consider the characteristics of these pixels, a problem may occur in that the pixels are driven at undesired brightness. And, this may cause a problem that the image quality of the display panel is lowered.

The characteristics of the pixels may change with time or with the surrounding environment. However, when the panel driver supplies the data voltage without considering the changed characteristics of the pixels, a problem of deterioration of image quality, for example, a line defect, may occur.

In order to improve the problem of deterioration of image quality, the display device may further include a pixel sensing device that senses characteristics of the pixels. The pixel sensing device may check the characteristics of each pixel periodically or aperiodically and transfer the same to the panel driver. In addition, the panel driver compensates for the data voltage according to the characteristic value of each pixel received from the pixel sensing device, thereby solving the problem of deterioration of image quality due to the characteristic change of the pixel.

Meanwhile, the conventional pixel sensing device transmits raw sensing data generated by sensing a pixel to a panel driver as it is. However, this conventional method had some problems.

First, the conventional method has a problem of data loss or inefficiency of data transmission resulting from a mismatch between the sensing rate and the data transmission rate.

Specifically, when the data transmission rate indicating the number of transmissions of data per hour transmitted to the panel driver is lower than the sensing rate indicating the number of generations of the sensing data, some of the generated sensing data cannot be transmitted to the panel driving apparatus. There was a problem of data loss.

In addition, when the data transfer rate indicating the number of transmissions of data per hour transmitted to the panel driver is higher than the sensing rate indicating the number of generations of the sensing data per hour, some of the sensing data are duplicated to transmit the data to the panel driver. There was a problem of inefficiency.

Secondly, the conventional method has a burden of data post-processing by removing the noise included in the sensing data or reprocessing the sensing data by transmitting the sensing data as it is to the panel driving apparatus. . In particular, the number of pixels is increasing in accordance with the recent trend of higher resolution, and the number of pixel sensing devices is increasing according to the increased number of pixels, and one panel driver, for example, a timing controller, is transmitted from a plurality of pixel sensing devices. As all the sensing data must be processed, the post-processing burden of the panel driving device is increasing.

In this context, an object of the present invention is, in one aspect, to provide a technique for increasing the utilization of data sensed at high speed with respect to a pixel.

In another aspect, it is an object of the present invention to provide a technique for solving the problem of data loss or inefficiency in data transmission resulting from a mismatch between the sensing rate and data transfer rate for a pixel.

In another aspect, it is an object of the present invention to provide a technique for reducing the computational load or data post-processing load of a device for driving a panel.

In order to achieve the above object, in one aspect, the present invention, by sensing the pixel whose brightness is controlled in accordance with the data voltage corresponding to the image data to generate the raw sensing data (raw sensing data) and memory the sensing data Sensing unit to store in; A processing unit which processes or selects at least one of the sensing data read from the memory to generate valid sensing data; And a driving control circuit for determining a characteristic value of the pixel by using sensing data of the pixel and compensating the image data applied to the pixel according to the characteristic value of the pixel. It provides a pixel sensing device comprising an output unit for transmitting.

In the pixel sensing apparatus, the sensing unit senses the current by sensing a current of an organic light emitting diode included in the pixel, a current of a driving transistor included in the pixel, or a voltage of a contact point of the organic light emitting diode and the driving transistor. You can generate data.

The driving control circuit may determine the threshold voltage or mobility of the driving transistor included in the pixel as the characteristic value of the pixel using the effective sensing data.

In another aspect, the present invention, L (L is a natural number of two or more) pixel sensing circuit for sensing the pixels to generate the sensing data, and transmit the effective sensing data generated by processing or selecting at least one of the sensing data. ; And the valid sensing data connected to the L pixel sensing circuits through one bus line and sequentially transmitted from each pixel sensing circuit through the one bus line, and using the valid sensing data. The present invention provides a panel driving apparatus including a driving control circuit that grasps a characteristic value of and compensates image data applied to the pixel according to the characteristic value of the pixel.

As described above, according to the present invention, the utilization of the data sensed at high speed with respect to the characteristic of the pixel is increased. In addition, according to the present invention, it is possible to solve the problem of data loss or inefficiency in data transmission caused by a mismatch between the sensing rate and the data transfer rate for the pixel. Further, according to the present invention, there is an effect that the computational load or data post-processing load of the device for driving the pixel is reduced.

1 is a block diagram of a display apparatus to which an embodiment of the present invention can be applied.

FIG. 2 is a diagram illustrating a pixel structure of each pixel of FIG. 1.

3 is a diagram illustrating an example of a pixel sensing circuit and a driving control circuit.

4 is a diagram illustrating an internal configuration of a pixel sensing circuit and a driving control circuit according to an exemplary embodiment of the present invention.

FIG. 5 is a diagram illustrating a processing flow from sensing to output in the pixel sensing circuit of FIG. 4.

6 and 7 illustrate a process of measuring a threshold voltage of a driving transistor included in a pixel.

8 is a diagram for describing a pixel sensing circuit performing data rejection on noise.

9 is a timing diagram of a first example of an operation sequence in one transmission period of a pixel sensing circuit.

10 is a timing diagram of a third example of an operation sequence in one transmission period of a pixel sensing circuit.

11 is a timing diagram of a second example of an operation sequence in one transmission period of a pixel sensing circuit.

12 is a diagram illustrating an internal configuration of a pixel sensing circuit according to another exemplary embodiment of the present invention.

13 is a block diagram of a panel driving apparatus according to another embodiment of the present invention.

14 is a timing diagram illustrating a sensing and transmission sequence in another embodiment of the present invention.

Fig. 15 is a configuration diagram of a panel driver for controlling transmission timing by using a carry signal.

Hereinafter, some embodiments of the present invention will be described in detail through exemplary drawings. In adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are assigned to the same components as much as possible even though they are shown in different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

In addition, in describing the component of this invention, terms, such as 1st, 2nd, A, B, (a), (b), can be used. These terms are only for distinguishing the components from other components, and the nature, order or order of the components are not limited by the terms. If a component is described as being "connected", "coupled" or "connected" to another component, that component may be directly connected to or connected to that other component, but there may be another configuration between each component. It is to be understood that the elements may be "connected", "coupled" or "connected".

Referring to FIG. 1, the display apparatus 100 may include a panel 110, a gate driver circuit 120, a data driver circuit 132, a pixel sensing circuit 134, a driving control circuit 140, and the like. .

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

The gate driver circuit 120 may supply a scan signal of a turn on voltage or a turn off voltage to the gate line GL. When the scan signal of the turn-on voltage is supplied to the pixel P, the pixel P is connected to the data line DL, and when the scan signal of the turn-off voltage is supplied to the pixel P, the pixel P and the data line The DL is disconnected.

The gate driver circuit 120 may be referred to as a gate driver, but the present invention is not limited to this name.

The data driver circuit 132 supplies a data voltage to the data line DL. The data voltage supplied to the data line DL may be supplied to the pixel P connected to the data line DL according to the scan signal.

The pixel sensing circuit 134 may sense each pixel P. FIG. In detail, the pixel sensing circuit 134 may sense electrical characteristic values formed in each pixel P, for example, voltage, current, and the like. The pixel sensing circuit 134 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. In this case, the sensing signal may be generated by the gate driving circuit 120.

The data driver circuit 132 and the pixel sensing circuit 134 may be implemented as an integrated integrated circuit, for example, the source driver 130, but the present invention is not limited thereto.

The driving control circuit 140 may supply various control signals to the gate driving circuit 120, the data driving circuit 132, and the pixel sensing circuit 130. The driving control circuit 140 may generate and transmit the gate control signal GCS to start the scan according to the timing implemented in each frame to the gate driving circuit 120. In addition, the driving control circuit 140 may output the image data RGB converted from the image data input from the outside to the data signal format used by the data driving circuit 132 to the data driving circuit 132. In addition, the driving control circuit 140 may transmit the data control signal DCS that controls the data driving circuit 132 to supply the data voltage to each pixel P according to each timing. In addition, the driving control circuit 140 may transmit a control signal (not shown) for determining the sensing timing and the transmission timing of the pixel sensing circuit 134 to the pixel sensing circuit 134.

The driving control circuit 140 may compensate and transmit the image data RGB according to the characteristics of the pixel P. FIG. In this case, the driving control circuit 140 may receive the sensing data SENSE from the pixel sensing circuit 134 to determine the characteristics of the pixel P.

The driving control circuit 140 may be referred to as a timing controller, but the present invention is not limited to such a name.

The panel 110 may be an organic light emitting display panel. In this case, 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 134 may have characteristics of these components included in each pixel P. It can be sensed and transmitted to the drive control circuit 140.

FIG. 2 is a diagram illustrating a pixel structure of each pixel of FIG. 1.

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

The organic light emitting diode OLED may be formed of an anode electrode, an organic layer, and a cathode electrode. The organic light emitting diode OLED emits light while the anode electrode is connected to the driving voltage EVDD and the cathode electrode is connected to the base voltage EVSS under the control of the driving transistor DRT.

The driving transistor DRT may 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 a source node or a 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 may be electrically connected between the data line DL and the second node N2 of the driving transistor DRT, and may be turned on by receiving a scan signal through the gate line GL.

When the switching transistor SWT is turned on, the data voltage Vdata supplied from 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, or may be an external capacitor intentionally designed outside the driving transistor DRT. Can be.

The sensing transistor SENT supplies the reference voltage Vref to the first node N1 of the driving transistor DRT and the first node N1, and provides an electrical characteristic value of the first node N1, for example, a voltage. The sensing line SL for sensing − may be electrically connected.

When the voltage of the first node N1 is sensed, the threshold voltage, mobility, and the like of the driving transistor DRT may be determined. In addition, when the voltage of the first node N1 is sensed, the degree of deterioration of the organic light emitting diode OLED, such as the parasitic capacitance of the organic light emitting diode OLED, may be determined.

The pixel sensing circuit described with reference to FIG. 1 (see 134 of FIG. 1) may sense the voltage of the first node N1 illustrated in FIG. 2 and transmit the sensed voltage to the driving control circuit 140. In addition, the driving control circuit 140 may determine the characteristics of each pixel P by analyzing the voltage of the first node N1.

Referring to FIG. 3, the pixel sensing circuit 10 may include a sensing unit 11, a memory 12, and an output unit 13. The driving control circuit 20 may include a sensing data receiver 21, an image data receiver 22, an image data compensator 23, a lookup table 24, an image data output unit 25, and the like. .

In the pixel sensing circuit 10, the sensing unit 11 may sense a pixel through the sensing line SL and store the sensed raw sensing data rSENSE in the memory 12. In addition, the output unit 13 may transmit the sensing data rSENSE stored in the memory 12 to the driving control circuit 20.

In the driving control circuit 20, the sensing data receiver 21 receives the sensing data rSENSE, and the image data receiver 22 receives the original image data RGB ′ from an external device, for example, a video controller. Receive

In the driving control circuit 20, the image data compensator 23 detects characteristic values of each pixel by using sensing data of each pixel and compensates original image data RGB ′ according to the characteristic value of each pixel. Image data RGB can be generated.

On the other hand, since the sensing data receiver 21 receives the sensing data rSENSE from the pixel sensing circuit 10 in the driving control circuit 20, the sensing data rSENSE can be used in the image data compensator 23. It converts the data into valid sensing data (SENSE). The sensing data rSENSE may include noise data as well as inappropriate data. If such noise data or non-conforming data is used in the image data compensator 23 as it is, the quality of the image data generated by the image data compensator 23 may be worse. ) Is processed or sorted to generate effective sensing data SENSE suitable for the image data compensator 23.

The image data compensator 23 applies the effective sensing data SENSE to the lookup table 24 to confirm a compensation value to be applied to each pixel, and applies the compensation value to the original image data RGB 'to provide a data driving circuit ( Image data RGB to be transmitted) may be generated. The image data output unit 25 may transmit the image data RGB to the data driving circuit (see 132 of FIG. 1).

Meanwhile, the data transfer rate indicating the number of data transmitted by the output unit 13 per hour in the pixel sensing circuit 10-in FIG. 3, the sensing data rSENSE-is the sensing data rSENSE of the sensing unit 11. It may be lower than the sensing rate indicating the number of generations per hour. Accordingly, since the output unit 13 cannot transmit the sensing data rSENSE at high speed even though the sensing unit 11 senses the pixels at high speed, the sensing data rSENSE received by the driving control circuit 20 is detected. ) Is limited to the data transfer rate of the output unit 13.

On the contrary, when the data transmission rate is higher than the sensing rate, some of the sensing data rSENSE are duplicated and transmitted because the transmission speed of the sensing data is faster than the generation speed of the sensing data rSENSE.

Also, the pixel sensing circuit 10 transmits all the sensing data rSENSE sensed regardless of the need of another device receiving the sensing data rSENSE, for example, the driving control circuit 20. There is a problem of increasing the computational load of the device.

As an example, the driving control circuit 20 may require only the highest value or the maximum value data among the sensed data. In this case, the pixel sensing device 10 transmits all the sensing data rSENSE. The sensing data receiver 21 selects necessary data from the sensing data rSENSE received by the driving control circuit 20. Accordingly, there is a problem that the data transfer load increases and the computational load of the drive control circuit 20 increases according to data selection. In addition, since the pixel sensing circuit 10 transmits the sensing data rSENSE as it is, the sensing data receiver 21 in the driving control circuit 20 should remove noise included in the received sensing data rSENSE. There is also a data post-processing burden.

In order to solve this problem, an embodiment of the present invention provides a technique of processing the sensing data in the pixel sensing circuit to generate valid sensing data, and transmitting the valid sensing data to the driving control circuit.

Referring to FIG. 4, the pixel sensing circuit 134 may include a sensing unit 410, a memory 420, an output unit 430, a processing unit 440, and the driving control circuit 140 may include sensing data. The receiver 141 may include an image data receiver 22, an image data compensator 23, a lookup table 24, and an image data output unit 25.

In the pixel sensing circuit 134, the sensing unit 410 senses an electrical characteristic value of the pixel, for example, the voltage or current of the first node N1 in FIG. 2 through the sensing line SL. The sensing unit 410 may receive an analog electrical signal from the sensing line SL, and the sensing unit 410 converts the analog electrical signal into digital data (ADC: Analog-Digital Converter). It may include. The sensing unit 410 may generate and store the sensing data rSENSE, which is digital data, through the analog-digital converter and store it in the memory 420.

In the pixel sensing circuit 134, the processor 440 may read the sensing data rSENSE stored in the memory 420, and then process the sensing data rSENSE to generate valid sensing data SENSE. In this case, the number of the effective sensing data SENSE may be smaller than the number of the sensing data rSENSE. When filtering noise or removing some data from the sensing data rSENSE and generating the valid sensing data SENSE, the number of the valid sensing data SENSE is the number of the sensing data rSENSE as described above. May be less.

According to an exemplary embodiment, the number of generated effective sensing data SENSE may be greater than the number of rose sensing data rSENSE. When the processor 440 further analyzes the sensing data rSENSE to derive the detailed information, the number of the valid sensing data SENSE may be larger than the number of the sensing data rSENSE.

As an example of post-data processing, the processor 440 may generate the effective sensing data SENSE by filtering the sensing data rSENSE. The processor 440 may generate valid sensing data SENSE by moving-averaging the sensing data rSENSE. Alternatively, the processor 440 may generate the effective sensing data SENSE by filtering only data of a band required from the sensing data rSENSE through low band filtering, mid band filtering, or high band filtering.

The processing unit 440 stores the generated effective sensing data SENSE again in the memory 420, and the output unit 430 stores the valid sensing data SENSE stored in the memory 420 such as the drive control circuit 140. You can send it to another device.

Meanwhile, the sensing unit 410 may sense an electrical characteristic value of the pixel at a first rate. For example, the sensing unit 410 may sense an electrical characteristic value of the pixel at a rate of 10 MHz. When all of the sensed signals are converted into the sensing data rSENSE, the sensing data rSENSE may be stored in the memory 420 at a speed of 10 MHz.

The processor 440 may perform post-processing on the sensing data rSENSE to generate valid sensing data SENSE that can be transmitted at a second rate—wherein the second rate is valid per hour. It means the number of sensing data. The output unit 430 may transmit such effective sensing data SENSE at a second rate.

Here, the second rate may be slower than the first rate. In this case, the pixel sensing circuit 134 post-processes the sensing data rSENSE sensed by the sensing unit 410 at the first rate, and thus the ratio of the second rate that falls within the transmission rate range of the output unit 430. Effective sensing data (SENSE) can be generated. As a result, the pixel sensing circuit 134 may transmit the highly reliable sensing data-effective sensing data SENSE to another device such as the driving control circuit 140 while maintaining the effect of high speed sensing.

In addition, the driving control circuit 140, which compensates the image data applied to the pixel according to the characteristic value of the pixel, receives the effective sensing data SENSE instead of the sensing data rSENSE, thereby generating additional computation load such as noise filtering. It can be minimized.

Specifically, referring to FIG. 4, in the driving control circuit 140, the sensing data receiver 141 uses the valid sensing data SENSE received by the pixel sensing device 134 without additional calculations as it is. Can be delivered to. In addition, the

other components

22, 23, 24, and 25 may perform the same function as described with reference to FIG. 3.

As in the embodiment of FIG. 4, since the pixel sensing circuit 134 converts the sensing data rSENSE into the effective sensing data SENSE through its own operation and transmits it to the driving control circuit 140, the data transmission burden is applied. This reduces, the loss of data, and, in addition, the operational load of the drive control circuit 140 is minimized.

Referring to FIG. 5, the sensing unit 410 generates the sensing data rDATA by sensing the pixel-sensing electrical characteristic value of the pixel through the sensing line SL, and generates the generated sensing data rDATA. It may be stored in the first area 424 of the memory 420.

The processor 440 may read the sensing data rDATA from the first area 424 and then process the sensing data rDATA to generate valid sensing data pDATA. The processor 440 may store the effective sensing data pDATA in the second area 426 of the memory 420.

The output unit 430 may transmit the valid sensing data pDATA read from the second area 426 to the driving control circuit 140.

For example, the sensing unit 410 may generate A sensing data rDATA per second and store the sensing data rDATA in the first area 424 at an A rate per second. In addition, the processor 440 may generate B effective sensing data pDATA per second by performing data post-processing on the sensing data rDATA. The processor 440 may store the effective sensing data pDATA in the second area 426 at a rate of B per second. The output unit 430 may read the effective sensing data pDATA at C speeds per second and transmit the read effective sensing data pDATA to the driving control circuit 140.

In this process, the data post-processing of the processing unit 440 may be similar in function to the data post-processing performed by the driving control circuit, for example, the timing controller. For example, when the pixel sensing circuit transmits the sensing data as it is to the driving control circuit-in the conventional method, the driving control circuit performs a filtering operation to remove noise, and the filtering operation is performed to the processing unit 440. It may be similar to the data post-processing work performed by. Accordingly, since the effective sensing data from which the noise is removed by the processor 440 is transmitted to the driving control circuit 140, the driving control circuit 140 does not have to perform a noise filtering operation, and the driving control circuit 140 The computational load of is reduced. In addition, since the output unit 430 transmits effective sensing data from which noise is removed without transmitting noise data, the data transmission load is also reduced.

The sensing unit 410, the processing unit 440, and the output unit 140 may operate in synchronization with the control signals CTR1, CTR2, and CTR3 received from the driving control circuit 140.

The sensing unit 410 may generate the sensing data rDATA according to the first period indicated by the first control signal CTR1 received from the driving control circuit 140. The first control signal CTR1 may be a clock signal but is not limited thereto. Here, the first period may be equal to the inverse of the sensing rate indicating the number of generation of the sensing data per hour.

The output unit 140 may transmit valid sensing data pDATA according to a second period indicated by the second control signal CTR2 received from the driving control circuit 140. The second control signal CTR2 may be a clock signal but is not limited thereto. Here, the second period may be equal to the inverse of the data transmission rate indicating the number of effective sensing data transmissions per hour.

The processor 440 may generate valid sensing data pDATA according to a third period indicated by the third control signal CTR3 received from the driving control circuit 140. The third period may be longer than or equal to the first period. The second period may be longer than or equal to the third period.

On the other hand, the processor may select only the data satisfying a specific condition among the sensing data generated in a predetermined period to generate the effective sensing data.

As a specific condition, the condition of maximum value or minimum value may be used. For example, the processor may generate the effective sensing data by selecting only the maximum value data or the minimum value data among the sensing data.

As another example of the specific condition, a condition in which the deviation from the previous data falls within a certain range may be used.

For example, when measuring the threshold voltage of the driving transistor included in the pixel, the driving control circuit measures the threshold voltage using the sensing data at the time when the source voltage of the driving transistor is not changed. In this case, the processor may generate valid sensing data by selecting only data whose deviation from the immediately preceding data of the sensing data is within a predetermined range, in other respects, data at the time when the value does not change. In this case, the drive control circuit can receive only necessary data while reducing a communication load for unnecessary data and an operation load according to data selection.

More details will be described with reference to FIGS. 6 and 7.

6 and 7, when sensing the threshold voltage of the driving transistor DRT, each of the source voltage Vs and the gate voltage Vg of the driving transistor DRT is used for sensing the reference voltage Vref and the threshold voltage. It is initialized to the data voltage Vdata.

Thereafter, when the supply of the reference voltage Vref is stopped and the source node of the driving transistor DRT is floating, the source voltage Vs is increased. The source voltage Vs of the driving transistor DRT gradually decreases, but becomes saturated as the gate-source voltage becomes the threshold voltage Vth.

The pixel sensing circuit 134 senses the source voltage Vs of the driving transistor DRT to generate the sensing data, and selects only the data having a deviation from the previous data within a predetermined range from the sensing data to the driving control circuit. Can transmit

In the pixel sensing circuit 134, the deviation from the immediately preceding data is substantially close to zero (in the case of T (n) and T (n-1) in FIG. 7), as well as the first deviation ( Data may be selected and transmitted from the portion corresponding to Δv) —the portion corresponding to T (m) and T (m−1) in FIG. 7. In the latter case, even though a driving load for data selection occurs in the drive control circuit that receives the valid sensing data, the degree of freedom for data selection in the drive control circuit is increased.

On the other hand, the pixel sensing circuit, for example, the processing unit, may generate effective sensing data by performing data rejection processing on data satisfying a specific condition among the sensing data.

As shown in FIG. 8, the data sensed at the first time T (l) has a constant deviation Δv from the data sensed at the previous time—the second time T (l-1). have. In addition, the data sensed at the second time T (l-1) has a constant deviation Δv from the data sensed at the previous time-the third time T (l-2). The data sensed at the second time T (l-1) is data due to a single noise.

The pixel sensing circuit generates the effective sensing data through data rejection, which removes data whose deviation from the previous data is out of a predetermined range among the rose sensing data, thereby removing the one-time noise.

The pixel sensing circuit may generate valid sensing data by post-processing the sensing data, and then transmit the valid sensing data to the driving control circuit. At this time, since the pixel sensing circuit processes the sensing data in the low data state first, the driving control circuit can reduce the computational load required for the data post-processing. In addition, the pixel sensing circuit post-processes the sensing data to remove unnecessary data (eg, noisy data), and selects only necessary data to generate effective sensing data, thereby communicating between the pixel sensing circuit and the driving control circuit. The load can be reduced.

The driving control circuit performs a compensation process on the pixel using the effective sensing data received from the pixel sensing circuit, and transmits the image data corrected according to the compensation process to a source driver, for example, a data driving circuit. However, as described above, since data post-processing such as noise filtering and data selection is performed in the pixel sensing circuit, the computational load is reduced by that, and more computational resources can be allocated to pixel compensation.

Referring to FIG. 9, the sensing unit may sequentially generate N (N is a natural number) sensing data in one transmission period, and the processor may sequentially generate N valid sensing data in one transmission period. At this time, the sensing data and the effective sensing data may be generated while alternating. For example, when the sensing unit generates one sensing data, the processor may generate one valid sensing data by using the generated sensing data.

The output unit may transmit the last generated N-th valid sensing data in one transmission period to the driving control circuit.

This operation sequence can minimize the size of the memory. The sensing data and valid sensing data may be continuously replaced with newly generated values, so that the size of the memory storing the sensing data and valid sensing data may be minimized. In addition, since the output unit can transmit valid sensing data stored in the memory as it is, it becomes easy to change the transmission period.

Referring to FIG. 10, the sensing unit may sequentially generate N (N is a natural number) sensing data in one transmission period, and the processor may sequentially generate N valid sensing data in one transmission period. At this time, unlike the sequence of FIG. 9, generation of the sensing data and generation of the valid sensing data may be processed in parallel. For example, the processor may generate valid sensing data at a time when the sensing unit generates the sensing data. However, since valid sensing data may be generated only when at least one sensing data is present, the processor may generate valid sensing data after at least one sensing data is generated. Accordingly, the sequence of the sensing unit may be terminated first in one transmission period, and the sequence of the processing unit may be terminated later.

According to this operation sequence, the size of the memory can be minimized, and one transfer period can be shortened by parallel processing. The sensing data and valid sensing data may be continuously replaced with newly generated values, so that the size of the memory storing the sensing data and valid sensing data may be minimized. In addition, since the output unit can transmit valid sensing data stored in the memory as it is, it becomes easy to change the transmission period. In addition, since the sensing unit and the processing unit operate in parallel, one transmission period may be shortened or the number of operations of the sensing unit and the processing unit may increase in one transmission period.

Referring to FIG. 11, the sensing unit sequentially generates M (M is 2 or more natural) sensing data in one transmission period, and the processing unit generates M sensing data after generating M sensing data in one transmission period. Can be processed to generate the effective sensing data. The output unit may transmit the generated valid sensing data to the driving control circuit.

According to such an operation sequence, the computational load of the processor can be minimized. Since the processing unit may generate the effective sensing data by performing only one operation of the M sensing data, the computational load of the processing unit may be minimized.

Referring to FIG. 12, the pixel sensing circuit 1200 may include a sensing unit 1210, a memory 1220, an output unit 1230, a processing unit 1240, and the like.

The sensing unit 1210 senses an electrical characteristic value of the pixel, for example, the voltage or current of the first node N1 in FIG. 2 through the sensing line SL. The sensing unit 1210 may receive an analog electric signal from the sensing line SL, and the sensing unit 1210 may convert an analog electric signal into digital data to convert the analog electric signal into digital data (ADC: Analog-Digital Converter). It may include. The sensing unit 1210 may generate and store the sensing data rDATA, which is digital data, through the analog-digital converter and store it in the memory 1220.

The processor 1240 may generate the valid sensing data pDATA by reading the sensing data rDATA stored in the memory 1220 and processing the sensing data rDATA.

The processor 1240 may transfer the generated valid sensing data pDATA to the output unit 1230.

The output unit 1230 may transmit the effective sensing data pDATA directly received from the processing unit 1240 to another device such as the driving control circuit 140.

The sensing unit 1210 may generate the sensing data rDATA according to the first period indicated by the first control signal CTR1 received from the driving control circuit 140.

The processor 1240 may generate valid sensing data pDATA according to a second period indicated by the second control signal CTR2 received from the driving control circuit 140. In addition, since the output unit 1230 transmits the effective sensing data pDATA directly received from the processing unit 1240, the output unit 1230 may operate in conjunction with the second control signal CTR2.

Referring to FIG. 13, the panel driver 1300 may include a driving control circuit 1340 and L

pixel sensing circuits

1334a, 1334b,..., 1334l (L is a natural number of two or more).

The driving control circuit 1340 may be connected to the L

pixel sensing circuits

1334a, 1334b,..., 1334l through one reception bus line RXL and one transmission bus line TXL.

The driving control circuit 1340 may transmit a control signal for the

pixel sensing circuits

1334a, 1334b,..., And 1334l through the reception bus line RXL. The control signal may include the first control signal CTR1, the second control signal CTR2, the third control signal CTR3, and the like. According to an embodiment, the first control signal CTR1 and the first control signal CTR1 may be included. The second control signal CTR2 and the third control signal CTR3 may be transmitted through a line separate from the receiving bus line RXL.

Each

pixel sensing circuit

1334a, 1334b, ..., 1334l senses the pixels to generate the sensing data, and processes the at least one sensing data to generate valid sensing data in one transmission bus line TXL. It may be transmitted to the drive control circuit 1340 through. Each of the

pixel sensing circuits

1334a, 1334b,..., 1334l may sequentially transmit valid sensing data in order to prevent data collision in one transmission bus line TXL.

As an example, the first pixel sensing circuit 1334a first transmits the effective sensing data to the driving control circuit 1340, and the K (K is two or more natural numbers less than or equal to L) pixel sensing circuits are made of (K−). 1) The pixel sensing circuit may transmit valid sensing data after transmitting valid sensing data.

The driving control circuit 1340 compares the predetermined number of pixel sensing circuits (L) with the number of valid sensing data received, so that the L

pixel sensing circuits

1334a, 1334b, ..., 1334l are all valid sensing data. It can be determined whether or not to transmit.

Meanwhile, the display device may distinguish the display period from the blank period, and display an image by driving pixels in the display period. The L

pixel sensing circuits

1334a, 1334b,..., 1334l may sense the pixel in a blank period in which the pixel is not driven. The L

pixel sensing circuits

1334a, 1334b, ..., 1334l may transmit valid sensing data in the blank period, but in some cases, at least one of the L

pixel sensing circuits

1334a, 1334b, ..., 1334l. The one or more pixel sensing circuits may transmit valid sensing data in the display section in which the pixel is driven.

The L

pixel sensing circuits

1334a, 1334b,..., 1334l may sense pixels in the same sensing period and transmit valid sensing data in different time periods.

Referring to FIG. 14, the L

pixel sensing circuits

1334a, 1334b,..., And 1334l may sense the pixel N times in the same sensing period. The L

pixel sensing circuits

1334a, 1334b,..., 1334l may post-process the sensing data generated N times in the same time interval to generate valid sensing data.

Meanwhile, the L

pixel sensing circuits

1334a, 1334b,..., 1334l may transmit valid sensing data at different time intervals to prevent data collision on the transmission bus line.

In this case, the sensing period for sensing the pixel is included in the blank period, and part or all of the time for generating valid sensing data and the time for transmitting valid sensing data may be included in the display period.

Each

pixel sensing circuit

1334a, 1334b,..., 1334l may transmit valid sensing data in synchronization with a carry signal.

Referring to FIG. 15, the panel driving apparatus 1500 may include a driving control circuit 1540 and L

pixel sensing circuits

1534a, 1534b,..., 1534l.

The driving control circuit 1540 may be connected to the L

pixel sensing circuits

The driving control circuit 1540 may transmit a control signal for the

pixel sensing circuits

1534a, 1534b,..., 1534l through the reception bus line RXL.

Each of the

pixel sensing circuits

1534a, 1534b,..., 1534l generates the sensing data by sensing the pixel and processes the at least one valid sensing data into one transmission bus line. The TXL may be transmitted to the driving control circuit 1540. Each of the

pixel sensing circuits

1534a, 1534b,..., 1534l may sequentially transmit valid sensing data in order to prevent data collision on one transmission bus line TXL.

The transmission timing in each

pixel sensing circuit

1534a, 1534b, ..., 1534l may be determined by the carry signal CR.

The first pixel sensing circuit 1534a may receive the carry signal CR from the driving control circuit 1540, and the K pixel sensing circuit may receive the carry signal CR from the (K-1) th pixel sensing circuit. have.

The first pixel sensing circuit 1534a may be connected to the driving control circuit 1540 by a carry signal line. The first pixel sensing circuit 1534a may receive the carry signal CR from the driving control circuit 1540 through the carry signal line.

The K-th pixel sensing circuit and the (K-1) th pixel sensing circuit may be connected by a carry signal line. The K-th pixel sensing circuit may receive the carry signal CR from the (K-1) th pixel sensing circuit.

The Kth pixel sensing circuit receives the carry signal CR from the (K-1) th pixel sensing circuit and transmits valid sensing data, and then transfers the carry signal CR back to the (K + 1) th pixel sensing circuit. Therefore, the next pixel sensing circuit can transmit valid sensing data.

Each

pixel sensing circuit

1534a, 1534b, ..., 1534l transmits the carry signal CR in this order, and finally, the L pixel sensing circuit 1534l that receives the carry signal CR is driven. The carry signal CR may be transmitted to the control circuit 140. In addition, the driving control circuit 140 may verify that all the

pixel sensing circuits

1534a, 1534b,..., 1534l have normally transmitted valid sensing data through the received carry signal CR.

On the other hand, the L-th pixel sensing circuit 1534l which finally receives the carry signal CR may not transmit the carry signal CR to the outside. At this time, the driving control circuit 140 compares the number of preset pixel sensing circuits (L) with the number of valid sensing data received, and thus the L

pixel sensing circuits

1534a, 1534b, ..., 1534l are all valid. It is possible to determine whether the sensing data is transmitted.

According to the embodiment described above, the utilization of the data sensed at high speed with respect to the characteristics of the pixel can be increased. Further, according to this embodiment, it is possible to solve the problem of data loss or inefficiency in data transmission caused by a mismatch between the sensing rate and the data transfer rate for the pixel. Further, according to this embodiment, there is an effect that the computational load or data post-processing load of the device for driving the pixel is reduced.

The terms "comprise", "comprise" or "having" described above mean that a corresponding component may be included unless specifically stated otherwise, and thus does not exclude other components. It should be construed that it may further include other components. All terms, including technical and scientific terms, have the same meanings as commonly understood by one of ordinary skill in the art unless otherwise defined. Terms commonly used, such as terms defined in a dictionary, should be interpreted to coincide with the contextual meaning of the related art, and shall not be construed in an ideal or excessively formal sense unless explicitly defined in the present invention.

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention pertains may make various modifications and changes without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

CROSS-REFERENCE TO RELATED APPLICATION

This patent application claims priority to Korean Patent Application No. 10-2016-0050639 filed with Korea on April 26, 2016 and Patent Application No. 10-2017-0051366 filed with Korea on April 21, 2017. The contents of which are hereby incorporated by reference in their entirety. In addition, if this patent application claims priority for the same reason for countries other than the United States, all its contents are incorporated into this patent application by reference.

Claims

A sensing unit configured to generate a raw sensing data by sensing a pixel whose brightness is controlled according to a data voltage corresponding to the image data, and to store the sensing data in a memory;

A processing unit which processes or selects at least one of the sensing data read from the memory to generate valid sensing data; And

Transmitting at least one effective sensing data to a drive control circuit for determining a characteristic value of the pixel by using sensing data of the pixel and compensating the image data applied to the pixel according to the characteristic value of the pixel. Output

Pixel sensing device comprising a.
The method of claim 1,

The drive control circuit,

And a threshold voltage or a mobility of a driving transistor included in the pixel as the characteristic value of the pixel using the effective sensing data.
The method of claim 1,

The sensing unit,

And sensing the current of the organic light emitting diode included in the pixel, the current of the driving transistor included in the pixel, or the voltage of the contact point of the organic light emitting diode and the driving transistor to generate the sensing data.
The method of claim 1,

And the number of generations of the sensing data generated by the sensing unit per hour is greater than the number of transmissions of effective sensing data transmitted by the output unit per hour.
The method of claim 1,

The sensing unit stores the sensing data in the first area of the memory,

The processing unit stores the valid sensing data in a second area of the memory,

And the output unit transmits valid sensing data read from the second area to the driving control circuit.
The method of claim 1,

And the output unit receives the valid sensing data directly from the processing unit and transmits the valid sensing data to the driving control circuit.
The method of claim 1,

The sensing unit generates the sensing data according to a first period indicated by a first control signal received from the driving control circuit.

And the output unit transmits the valid sensing data according to a second period indicated by a second control signal received from the driving control circuit.
The method of claim 7, wherein

The processor generates the valid sensing data according to a third period indicated by a third control signal received from the driving control circuit.

And the third period is longer than or equal to the first period, and the second period is longer than or equal to the third period.
The method of claim 1,

The sensing unit sequentially generates N pieces of the sensing data in one transmission period (N is a natural number),

The processing unit sequentially generates the N pieces of valid sensing data in the one transmission period,

And the output unit transmits the Nth valid sensing data to the driving control circuit in the one transmission period.
The method of claim 1,

The sensing unit sequentially generates M (M is two or more natural numbers) of the sensing data in one transmission period,

And the processing unit processes or selects the M sensing data in the one transmission period to generate the valid sensing data.
L (L is a natural number of two or more) pixel sensing circuit for generating the sensing data by sensing the pixel and transmitting the effective sensing data generated by processing or selecting at least one of the sensing data; And

The L pixel sensing circuits are connected to one bus line, and receive the valid sensing data transmitted from each pixel sensing circuit sequentially through the one bus line, and use the valid sensing data to A driving control circuit for grasping a characteristic value and compensating image data applied to the pixel according to the characteristic value of the pixel

Panel drive device comprising a.
The method of claim 11,

The L pixel sensing circuits,

And a panel sensing device which senses the pixel in the same sensing section and transmits the valid sensing data in different time sections.
The method of claim 11,

The L pixel sensing circuits transmit the effective sensing data in synchronization with a carry signal,

The first pixel sensing circuit receives the carry signal from the driving control circuit, and the K (K is a natural number of two or more than L) pixel sensing circuits receive the carry signal from the (K-1) pixel sensing circuit. Receive panel driver.
The method of claim 13,

The drive control circuit,

And comparing the preset number of pixel sensing circuits with the number of valid sensing data received to determine whether all L pixel sensing circuits have transmitted the valid sensing data.
The method of claim 11,

The L pixel sensing circuits,

Sensing the pixel in a blank period in which the pixel is not driven,

At least one pixel sensing circuit of the L pixel sensing circuits,

And a panel driver for transmitting the effective sensing data in a display section in which the pixel is driven.