Driving circuit and driving method

Abstract

The invention relates to a driving circuit and a driving method. The driving circuit comprises a pixel unit; the driving module is used for driving the pixel units to perform scanning display; the switch module is in a closed state in the scanning time and in a conducting state in the idle time, and voltage on the pixel units is taken out; the logic module enables the switch module to be in a closed state in the scanning time and enables the switch module to be in an on state in the idle time; the comparison module is used for comparing the voltages on the pixel units and generating a comparison result; and the control module controls the driving module to drive the pixel units to perform scanning display in the scanning time, controls the logic module to enable the switch module to be in a conduction state in the idle time, and judges whether the pixel units are dead pixels or not according to a comparison result provided by the comparison module. The detection accuracy of the method is high.

Description

Technical Field

[0001] The present application relates to the technical field of display screens, and in particular to a driving circuit and a driving method suitable for display screens. Background Art

[0002] Micro_LED display screens have attracted wide attention due to their advantages such as high integration, high brightness, and low power consumption, and have broad market prospects. However, due to the complex reasons related to materials, devices, and processes involved in the manufacturing process, there may be bad pixels on the finished product, so testing the Micro_LED display screen to determine whether there are bad pixels on it is a key step. However, the existing detection method generally powers on the Micro_LED display screen, then takes a photo and uses image recognition to determine whether there are bad pixels on the Micro_LED display screen. This detection method is not very accurate and may result in misjudgment. Summary of the invention

[0003] The purpose of the present application is to provide a driving circuit and a driving method, which are suitable for display screens and have a high accuracy rate in detecting bad pixels on the display screen.

[0004] To achieve the above object, the present application provides a driving circuit suitable for a display screen, the driving circuit comprising:

[0005] Pixel unit;

[0006] A driving module, connected to the pixel unit, and used to drive the pixel unit to perform scanning and display;

[0007] A switch module is connected to the pixel unit, is in a closed state during the scanning time, is in a conducting state during the idle time, and takes out the voltage on the pixel unit;

[0008] A logic module connected to the switch module, which turns the switch module into a closed state during the scanning time and turns the switch module into a conducting state during the idle time;

[0009] A comparison module, connected to the switch module, compares the voltages on the pixel units and generates a comparison result;

[0010] The control module is connected to the driving module, the logic module and the comparison module. The control module controls the driving module to drive the pixel unit to scan and display during the scanning time. The control module controls the logic module to make the switch module in the on state during the idle time, and determines whether the pixel unit is a bad pixel according to the comparison result provided by the comparison module.

[0011] In one embodiment, the switch module is a MOS tube having an input end, an output end, and a control end. The input end of the switch module is the source end or the drain end of the MOS tube, the output end of the switch module is the drain end or the source end of the MOS tube, and the control end of the switch module is the gate end of the MOS tube.

[0012] In one embodiment, the logic module is an AND gate circuit, two input ends of the AND gate circuit respectively receive a row selection signal and a column selection signal sent by the control module, and an output end of the AND gate circuit is connected to the switch module.

[0013] In one embodiment, the comparison module includes a first comparator and a second comparator, the positive input end of the first comparator is connected to the switch module, the negative input end of the first comparator receives a first reference voltage, the output end of the first comparator is connected to the control module, the first comparator is used to detect whether the pixel unit is open, the negative input end of the second comparator is connected to the switch module, the positive input end of the second comparator receives a second reference voltage, the output end of the second comparator is connected to the control module, and the second comparator is used to detect whether the pixel unit is short-circuited. If the pixel unit is open or short-circuited, it is judged as a bad pixel.

[0014] In one embodiment, the driving circuit further includes a data buffer, which is connected to the control module and is used to store bad pixel information. When the data buffer is full, an interrupt is generated to notify the control module to suspend detection and move the bad pixel information.

[0015] In one embodiment, the data buffer is a FIFO, the control module is an MCU, and the pixel unit is a Micro_LED; the bad pixel information includes an abnormal type of the bad pixel and a position coordinate of the bad pixel, and the abnormal type includes an open circuit and a short circuit.

[0016] In one implementation, the positive electrode of the pixel unit is connected to the switch module and the driving module, and the negative electrode of the pixel unit is connected to a common end.

[0017] In one embodiment, the driving module receives the scanning signal and the data signal sent by the control module.

[0018] The present application also provides a driving method, which adopts the driving circuit as described above, and the driving method includes: the control module controls the driving module to drive the pixel unit to scan and display during the scanning time, the control module controls the logic module to make the switch module in the on state during the idle time, takes out the voltage on the pixel unit, sends it to the comparison module to compare the voltage on the pixel unit, generates a comparison result, and detects and determines whether the pixel unit is a bad pixel based on the comparison result provided by the comparison module.

[0019] In one embodiment, after all pixels are detected, the detection is stopped for a preset time and then restarted.

[0020] In summary, the beneficial effects of this application are:

[0021] The driving circuit and driving method of the present application are provided with a switch module, a logic module and a comparison module on the basis of the driving module, and in the process of normal operation of the display screen, in the idle time between the scanning time, the control logic module turns on the switch module, derives the voltage on the pixel unit, and sends it to the comparison module for comparison, so as to detect whether the pixel unit is normal or not. Because whether the voltage on the pixel unit is normal or not is a key indicator of whether the pixel unit is normal or not; when the pixel unit is normal, the voltage on the pixel unit is normal; when the pixel unit is abnormal, the voltage on the pixel unit is abnormal; therefore, the present application detects and determines the bad pixels on the display screen through the voltage on the pixel unit, and the detection accuracy is high. Moreover, the control module itself grasps the position coordinates of the pixel unit, so when the bad pixel unit is detected, the position coordinates of the bad pixel unit can also be accurately known, which further improves the accuracy and efficiency of the detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 A schematic diagram of a circuit structure of a driving circuit provided in the first embodiment of the present application;

[0024] Figure 2 for Figure 1 A schematic diagram of a pixel array of a display screen to which the driving circuit is applied is shown. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present application. In addition, it should be understood that the specific implementation methods described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0026] See also Figure 1 As shown, the present application provides a driving circuit suitable for a display screen, the driving circuit comprising:

[0027] Pixel unit 10;

[0028] A driving module 20, connected to the pixel unit 10, and used to drive the pixel unit 10 to perform scanning and display;

[0029] The switch module 30 is connected to the pixel unit 10, is in a closed state during the scanning time, and is in a conducting state during the idle time, and takes out the voltage on the pixel unit 10;

[0030] The logic module 40 is connected to the switch module 30, and makes the switch module 30 in a closed state during the scanning time, and makes the switch module 30 in a conducting state during the idle time;

[0031] A comparison module 50, connected to the switch module 30, compares the voltage on the pixel unit 10 and generates a comparison result;

[0032] The control module 60 is connected to the driving module 20, the logic module 40, and the comparison module 50. The control module 60 controls the driving module 20 to drive the pixel unit 10 to scan and display during the scanning time. The control module 60 controls the logic module 40 to make the switch module 30 in the on state during the idle time, and determines whether the pixel unit 10 is a bad pixel according to the comparison result provided by the comparison module 50.

[0033] Please refer to Figure 2 , Figure 2 The figure is a schematic diagram of a pixel array of a display screen using the driving circuit of the present application. Figure 2 For any pixel in Figure 1 The pixel unit 10, driving module 20, switch module 30, logic module 40, comparison module 50 shown in the figure, and the control module 60 can be shared by one display screen. In order to simplify the description, the whole text is described from the perspective of one pixel.

[0034] Among them, the driving module 20 can adopt the driving module 20 in any existing driving circuit. The existing driving circuit generally only has a driving module and a control module. During normal operation, the control module controls the driving module to drive and scan the pixel unit. The time period for driving and scanning is the scanning time. On the basis of the existing driving circuit, the present application adds a switch module 30, a logic module 40 and a comparison module 50, and improves the control module 60. During the idle time between scanning times (when the display screen displays the picture, the picture to be displayed is divided into frames for scanning and display, and there is an idle time between scanning frames, commonly known as tblank), the control module 60 controls the logic module 40 to turn on the switch module 30, thereby turning on the voltage on the pixel unit 10 ( Figure 1 The voltage on the pixel unit 10 (as shown in Vf_OUT) is derived and sent to the comparison module 50 for comparison, so as to detect and determine whether the pixel unit 10 is normal or not. Because whether the voltage on the pixel unit 10 (Micro_LED in a specific embodiment) is normal or not is a key indicator of whether the pixel unit 10 is normal or not; when the pixel unit 10 is normal, the voltage on the pixel unit 10 is normal; when the pixel unit 10 is abnormal, the voltage on the pixel unit 10 is abnormal. Therefore, the present application detects and determines the bad pixels on the display screen through the voltage on the pixel unit 10, and the detection accuracy is relatively high. Moreover, the control module 60 (MCU in a specific embodiment) performs detection during idle time, and the control module 60 itself controls the driving module 20 to scan and display the pixel unit 10 during the scanning time. The control module 60 itself grasps the position coordinates of the pixel unit 10, so when a bad pixel unit 10 is detected, the position coordinates of the bad pixel unit 10 can also be accurately known (for example Figure 2 The pixel unit 10 marked in red indicates that it is a bad pixel), which further improves the accuracy and efficiency of detection.

[0035] In one embodiment, the switch module 30 is a MOS tube having an input end, an output end, and a control end. The input end of the switch module 30 is the source end or the drain end of the MOS tube, the output end of the switch module 30 is the drain end or the source end of the MOS tube, and the control end of the switch module 30 is the gate end of the MOS tube.

[0036] That is, in a simple implementation, the switch module 30 is implemented by a MOS tube. At this time, it is only necessary to use the gate end of the MOS tube as the control end of the switch module 30 to receive the logic control of the logic module 40; the source end and the drain end of the MOS tube are respectively used as the input end and the output end of the switch module 30. That is, when the source end of the MOS tube is used as the input end of the switch module 30, the drain end of the MOS tube is used as the output end of the switch module 30; or, when the drain end of the MOS tube is used as the input end of the switch module 30, the source end of the MOS tube is used as the output end of the switch module 30. Of course, according to actual needs, the switch module 30 can also adopt other replacement structures that can be easily thought of by those skilled in the art.

[0037] In one embodiment, the logic module 40 is an AND gate circuit, two input ends of the AND gate circuit respectively receive a row selection signal and a column selection signal sent by the control module 60 , and an output end of the AND gate circuit is connected to the switch module 30 .

[0038] Because the pixels of the display screen are arranged in an array, the corresponding pixel units 10 are also arranged in an array. Therefore, in a simple implementation, the logic module 40 can be implemented by an AND gate circuit, and at the same time cooperate with the control module 60 to adopt two selection signals (a row selection signal and a Figure 1 As shown in VCTRLA_IN; a column selection signal, Figure 1 VCTRLB_IN) as two input signals of the AND gate circuit to select a certain pixel unit 10. Of course, according to actual needs, the logic module 40 can also adopt other replacement structures that can be easily thought of by those skilled in the art. In addition, more specifically, the output end of the AND gate circuit is connected to the control end of the switch module 30 to control the conduction and closing of the switch module 30.

[0039] In one embodiment, the comparison module 50 includes a first comparator 51 and a second comparator 52, the positive input terminal of the first comparator 51 is connected to the switch module 30, the negative input terminal of the first comparator 51 receives a first reference voltage, the output terminal of the first comparator 51 is connected to the control module 60, the first comparator 51 is used to detect whether the pixel unit 10 is open, the negative input terminal of the second comparator 52 is connected to the switch module 30, the positive input terminal of the second comparator 52 receives a second reference voltage, the output terminal of the second comparator 52 is connected to the control module 60, and the second comparator 52 is used to detect whether the pixel unit 10 is short-circuited. If the pixel unit 10 is open or short-circuited, it is determined to be a bad pixel.

[0040] Because if the pixel unit 10 is abnormal, there are two main situations, one is that the pixel unit 10 is open circuit, and the other is that the pixel unit 10 is short circuit. Therefore, the present application sets a comparison module 50 composed of two comparators (a first comparator 51 and a second comparator 52) for each pixel unit 10 and is connected to the switch module 30. After the voltage on the pixel unit 10 is obtained through the switch module 30, the first comparator 51 detects whether the pixel unit 10 is open circuit through the voltage, and the second comparator 52 detects whether the pixel unit 10 is short circuit through the voltage. No matter whether the pixel unit 10 is detected to be open circuit or short circuit, as long as the control module 60 receives the comparison results output by the two comparators showing that the pixel unit 10 is open circuit or short circuit, the pixel unit 10 is determined to be a bad pixel.

[0041] More specifically, if the pixel unit 10 is open, it is equivalent to the pixel unit 10 being in a suspended state and not grounded, so the voltage on the pixel unit 10 is relatively high. Therefore, the output end of the switch module 30 is connected to the positive input end of the first comparator 51, and the negative input end of the first comparator 51 receives the first reference voltage ( Figure 1 ), so that the first comparator 51 can compare and detect whether the pixel unit 10 is open circuit. The comparison result of the first comparator 51 ( Figure 1 If the pixel unit 10 is short-circuited, it is equivalent to the pixel unit 10 being directly grounded, so the voltage on the pixel unit 10 is low, so the output end of the switch module 30 is connected to the negative input end of the second comparator 52, and the positive input end of the second comparator 52 receives the second reference voltage ( Figure 1 ), so that the second comparator 52 can compare and detect whether the pixel unit 10 is short-circuited. The comparison result of the second comparator 52 ( Figure 1 The control module 60 sends the comparison result of the first comparator 51 ( Figure 1 The comparison result of the second comparator 52 ( Figure 1 The signal level of VOUT_SHORT (shown in FIG. 1 ) is used to determine whether the pixel unit 10 is open circuit, short circuit (open circuit and short circuit are collectively referred to as abnormal) or normal.

[0042] In one embodiment, the driving circuit further includes a data buffer 70, which is connected to the control module 60. The data buffer 70 is used to store bad pixel information and generate an interrupt to notify the control module 60 to suspend detection and move the bad pixel information after the data is full.

[0043] Because there are tens of thousands of pixels in the pixel array of a display screen, each pixel has a pixel unit 10. If a pixel unit 10 is abnormal, it does not affect the normal use of the display screen; therefore, when a pixel unit 10 is detected to be abnormal, it is not necessary to respond immediately and take any action, but such abnormal information, also known as bad pixel information, can be stored in a data buffer 70 (FIFO in a specific embodiment), and the control module 60 can be notified to perform some corresponding processing after the number of bad pixels reaches a certain standard. For example, when the data buffer 70 is full of data, because it cannot continue to store data, an interrupt can be generated and sent to the control module 60 at this time, notifying the control module 60 to suspend detection and notifying the control module 60 to move the bad pixel information. After the control module 60 moves the bad pixel information in the data buffer 70 (moves data), the data buffer 70 is cleared again, and then the detection continues. For another example, when the number of bad pixels reaches a certain standard, a prompt message "There are many bad pixels, it is recommended to repair or replace as soon as possible" is displayed on the display screen. The bad pixel information, as can be understood from the above content, can include the abnormal type of the bad pixel and the position coordinates of the bad pixel, and the abnormal type includes open circuit and short circuit. In addition, it is also explained that a display screen can also share a data buffer 70.

[0044] Finally, in one embodiment, the positive electrode of the pixel unit 10 is connected to the switch module 30 and the driving module 20 , and the negative electrode of the pixel unit 10 is connected to a common terminal; the driving module 20 also receives a scanning signal and a data signal sent by the control module 60 .

[0045] As mentioned above, when the display screen displays a picture, it divides the picture into frames for scanning. The control module 60 sends a scanning signal ( Figure 1 SCAN) and data signals ( Figure 1 DATA in the figure) to each driving module 20 to control each driving module 20 to scan each pixel unit 10. The positive electrode of the pixel unit 10 is connected to the switch module 30 (more specifically, the input end of the switch module 30) and the driving module 20, and the negative electrode of the pixel unit 10 is connected to the common end ( Figure 1 The control module 60 can obtain the voltage on the pixel unit 10 during the idle time to detect and determine whether the pixel unit 10 is a bad pixel.

[0046] The second embodiment of the present application provides a driving method, which adopts the driving circuit as described above, and the driving method includes: the control module controls the driving module to drive the pixel unit to scan and display during the scanning time, and the control module controls the logic module to make the switch module in the on state during the idle time, takes out the voltage on the pixel unit, sends it to the comparison module to compare the voltage on the pixel unit, generates a comparison result, and detects and determines whether the pixel unit is a bad pixel according to the comparison result provided by the comparison module. That is, during the normal operation of the display screen, the control module controls each switch module to be turned on through each logic module during the idle time between the scanning times, obtains the voltage on each pixel unit, and detects the bad pixel on the display screen by judging whether the voltage is normal or not. The technical effects of the driving circuit of the present application described in the previous text when introducing the driving circuit of the present application, because the driving method of the present application adopts the aforementioned driving circuit, it also has the corresponding technical effects, which will not be repeated here.

[0047] In one embodiment, after all pixels are detected, the detection is stopped for a preset time, and then the detection is restarted. Of course, the specific length of the preset time can be set according to actual needs, and the present application does not have a specific limitation on this; and even in one embodiment, the detection can be stopped after one detection, that is, the display screen using the driving circuit of the present application is only detected once during each normal operation of the power supply, so as to reduce the power consumption of the display screen when it is used. Of course, when multiple consecutive detections are performed, the control module can accumulate the bad pixel data obtained from each detection to facilitate subsequent management, maintenance, etc.

[0048] In summary, the beneficial effects of this application are:

[0049] The driving circuit and driving method of the present application are provided with a switch module, a logic module and a comparison module on the basis of the driving module, and in the process of normal operation of the display screen, in the idle time between the scanning time, the control logic module turns on the switch module, derives the voltage on the pixel unit, and sends it to the comparison module for comparison, so as to detect whether the pixel unit is normal or not. Because whether the voltage on the pixel unit is normal or not is a key indicator of whether the pixel unit is normal or not; when the pixel unit is normal, the voltage on the pixel unit is normal; when the pixel unit is abnormal, the voltage on the pixel unit is abnormal; therefore, the present application detects and determines the bad pixels on the display screen through the voltage on the pixel unit, and the detection accuracy is high. Moreover, the control module itself grasps the position coordinates of the pixel unit, so when the bad pixel unit is detected, the position coordinates of the bad pixel unit can also be accurately known, further improving the accuracy and efficiency of the detection.

[0050] The technical solutions provided by the embodiments of the present application are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A driving circuit, suitable for a display screen, characterized in that: The driving circuit comprises: Pixel unit; A driving module, connected to the pixel unit, and used to drive the pixel unit to perform scanning and display; A switch module is connected to the pixel unit, is in a closed state during the scanning time, is in a conducting state during the idle time, and takes out the voltage on the pixel unit; A logic module connected to the switch module, which turns the switch module into a closed state during the scanning time and turns the switch module into a conducting state during the idle time; A comparison module, connected to the switch module, compares the voltages on the pixel units and generates a comparison result; The control module is connected to the driving module, the logic module and the comparison module. The control module controls the driving module to drive the pixel unit to scan and display during the scanning time. The control module controls the logic module to make the switch module in the on state during the idle time, and determines whether the pixel unit is a bad pixel according to the comparison result provided by the comparison module.

2. The driving circuit according to claim 1, characterized in that: The switch module is a MOS tube having an input end, an output end, and a control end. The input end of the switch module is the source end or the drain end of the MOS tube, the output end of the switch module is the drain end or the source end of the MOS tube, and the control end of the switch module is the gate end of the MOS tube.

3. The driving circuit according to claim 1, wherein: The logic module is an AND gate circuit, two input ends of the AND gate circuit respectively receive a row selection signal and a column selection signal sent by the control module, and an output end of the AND gate circuit is connected to the switch module.

4. The driving circuit according to claim 1, wherein: The comparison module includes a first comparator and a second comparator, the positive input end of the first comparator is connected to the switch module, the negative input end of the first comparator receives a first reference voltage, the output end of the first comparator is connected to the control module, the first comparator is used to detect whether the pixel unit is open, the negative input end of the second comparator is connected to the switch module, the positive input end of the second comparator receives a second reference voltage, the output end of the second comparator is connected to the control module, the second comparator is used to detect whether the pixel unit is short-circuited, and the pixel unit is judged as a bad pixel if it is open or short-circuited.

5. The driving circuit according to claim 1, characterized in that: The driving circuit also includes a data buffer, which is connected to the control module and is used to store bad pixel information. When the data buffer is full, an interrupt is generated to notify the control module to suspend detection and move the bad pixel information.

6. The driving circuit according to claim 5, characterized in that: The data buffer is a FIFO, the control module is an MCU, and the pixel unit is a Micro_LED; the bad pixel information includes an abnormal type of the bad pixel and a position coordinate of the bad pixel, and the abnormal type includes an open circuit and a short circuit.

7. The driving circuit according to claim 1, characterized in that: The positive electrode of the pixel unit is connected to the switch module and the driving module, and the negative electrode of the pixel unit is connected to a common end.

8. The driving circuit according to claim 1, characterized in that: The driving module receives the scanning signal and the data signal sent by the control module.

9. A driving method, characterized in that: Using the driving circuit as described in any one of claims 1 to 8, the driving method includes: the control module controls the driving module to drive the pixel unit to scan and display during the scanning time, the control module controls the logic module to make the switch module in the on state during the idle time, takes out the voltage on the pixel unit, sends it to the comparison module to compare the voltage on the pixel unit, generates a comparison result, and detects and determines whether the pixel unit is a bad pixel based on the comparison result provided by the comparison module.

10. The driving method according to claim 9, characterized in that: After all pixel units are detected, the system stays for a preset time and then restarts the detection.

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