Control circuit of display panel and display panel

Abstract

The present application discloses a control circuit for a display panel and a display panel, which belongs to the field of display technology. The display panel includes a GOA circuit, a power supply circuit and a pixel unit. The GOA circuit is configured to control the pixel unit to turn on using the turn-on voltage provided by the power supply circuit. The control circuit includes: a detection circuit, coupled to the GOA circuit, and configured to detect the output signal of the GOA circuit and provide a first parameter, the first parameter characterizing the voltage climbing speed of the output signal; a main control circuit, coupled to the detection circuit and the power supply circuit respectively, and configured to determine the target turn-on voltage according to the first parameter and the reference parameter, and control the power supply circuit to provide the target turn-on voltage to the GOA circuit. According to the control circuit of the present application, the driving capability of the GOA circuit is judged by detecting the output signal of the GOA circuit, and then the turn-on voltage provided by the power supply circuit to the GOA circuit is dynamically adjusted to ensure that the GOA circuit can turn on the TFT, thereby avoiding aging caused by continuous use of high voltage.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a control circuit of a display panel and a display panel. Background Art

[0002] LCD (Liquid Crystal Display) panels use liquid crystal molecules to control the light transmittance of each sub-pixel, resulting in distinct color variations. Each sub-pixel is connected to a main scanning control circuit and a data circuit via a thin-film transistor (TFT). The main scanning control circuit turns on the TFT, while the signal circuit charges the liquid crystal molecules, causing them to rotate.

[0003] To achieve narrow panels, the main scanning control circuit is integrated into the array substrate, commonly known as the GOA (Gate on Array) circuit. In low-temperature environments, or as the panel ages, the GOA circuit requires a higher drive voltage to control the TFTs. Typically, to achieve startup, the GOA circuit has a high turn-on voltage (VGH) and turn-off voltage (VGL). However, this high voltage across the GOA circuit increases power consumption and accelerates GOA aging. Summary of the Invention

[0004] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a control circuit for a display panel and a display panel.

[0005] In a first aspect, the present application provides a control circuit for a display panel, the display panel including a GOA circuit, a power supply circuit, and a pixel unit. The GOA circuit is configured to control the pixel unit to turn on using a turn-on voltage provided by the power supply circuit. The control circuit includes:

[0006] a detection circuit coupled to the GOA circuit and configured to detect an output signal of the GOA circuit and provide a first parameter, the first parameter representing a voltage rise speed of the output signal;

[0007] The main control circuit is coupled to the detection circuit and the power circuit respectively, and is configured to determine a target turn-on voltage according to the first parameter and the reference parameter, and control the power circuit to provide the target turn-on voltage to the GOA circuit.

[0008] According to the control circuit of the present application, the output signal of the GOA circuit is detected to determine the driving capability of the GOA circuit, and then the turn-on voltage provided by the power supply circuit to the GOA circuit is dynamically adjusted to ensure that the GOA circuit can turn on the TFT, thereby avoiding aging caused by continuous use of high voltage.

[0009] According to one embodiment of the present application, the first parameter includes a first time parameter for the voltage of the output signal to rise from the first voltage to the second voltage, and / or a second time parameter for the output signal to remain greater than or equal to a third voltage.

[0010] According to one embodiment of the present application, the first parameter includes a first time parameter, and the detection circuit includes:

[0011] a first comparison circuit configured to provide a first comparison signal when the first sampling voltage is greater than or equal to the first voltage and less than or equal to the second voltage, the first sampling voltage representing a voltage value of the output signal;

[0012] The first calculation circuit is coupled to the first comparison circuit and is configured to determine a first time parameter according to the first comparison signal.

[0013] According to one embodiment of the present application, the detection circuit further includes:

[0014] The first reference circuit is configured to generate a first voltage and a second voltage according to a first coefficient, a second coefficient, and a current turn-on voltage of the GOA circuit, wherein the first coefficient is smaller than the second coefficient.

[0015] According to one embodiment of the present application, the first parameter includes a second time parameter, and the detection circuit includes:

[0016] a second comparison circuit configured to provide a second comparison signal when the second sampling voltage is greater than or equal to a third voltage, the second sampling voltage representing a voltage value of the output signal;

[0017] The second calculation circuit is coupled to the second comparison circuit and configured to determine a second time parameter according to the second comparison signal.

[0018] According to one embodiment of the present application, the detection circuit further includes:

[0019] The second reference circuit is configured to generate a third voltage according to a third coefficient and a current turn-on voltage of the GOA circuit.

[0020] According to one embodiment of the present application, the reference parameter includes a target range;

[0021] The main control circuit is configured to control the power supply circuit to maintain a current start-up voltage when the first parameter is within a target range;

[0022] The main control circuit is configured to control the power supply circuit to reduce or increase the current start-up voltage when the first parameter is outside the target range.

[0023] According to one embodiment of the present application, the reference parameter includes a first reference range and a second reference range. When the first parameter changes with an upward trend, the first reference range is used as the target range. When the first parameter changes with a downward trend, the second reference range is used as the target range.

[0024] According to one embodiment of the present application, the first parameter is positively correlated with the voltage climbing speed;

[0025] The main control circuit is configured to control the power supply circuit to reduce the current start-up voltage when the first parameter is less than the minimum value of the target range;

[0026] The main control circuit is configured to control the power supply circuit to increase the current start-up voltage when the first parameter is greater than a maximum value of the target range.

[0027] According to one embodiment of the present application, the first parameter is negatively correlated with the voltage climbing speed;

[0028] The main control circuit is configured to control the power supply circuit to increase the current start-up voltage when the first parameter is less than the minimum value of the target range;

[0029] The main control circuit is configured to control the power supply circuit to reduce the current start-up voltage when the first parameter is greater than a maximum value of the target range.

[0030] According to one embodiment of the present application, the GOA circuit includes a first GOA circuit and a second GOA circuit provided on both sides of the pixel unit, and the control circuit further includes:

[0031] The switching circuit is coupled to the first GOA circuit, the second GOA circuit and the detection circuit respectively, and is configured to selectively connect the detection circuit to the first GOA circuit or connect the detection circuit to the second GOA circuit.

[0032] According to one embodiment of the present application, the main control circuit is further configured to determine a target turn-off voltage according to the first parameter and the reference parameter, and control the power supply circuit to provide the target turn-off voltage to the GOA circuit.

[0033] In a second aspect, the present application provides a display panel, including an array substrate and a control circuit board, the array substrate is provided with a pixel unit and a GOA circuit, and the control circuit board is provided with a power circuit and a control circuit according to any one of claims 1-12.

[0034] According to the display panel of the present application, the output signal of the GOA circuit is detected to determine the driving capability of the GOA circuit, and then the turn-on voltage provided by the power supply circuit to the GOA circuit is dynamically adjusted to ensure that the GOA circuit can turn on the TFT, thereby avoiding aging caused by continuous use of high voltage.

[0035] According to one embodiment of the present application, the control circuit board is provided with a power management unit and a timing control unit, the detection circuit and the power circuit in the control circuit are integrated into the integrated power management unit, and the main control circuit in the control circuit is integrated into the timing control unit.

[0036] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0038] Figure 1 This is one of the structural diagrams of the display panel provided in the embodiment of the present application;

[0039] Figure 2 This is one of the structural block diagrams of the control circuit provided in the embodiment of the present application;

[0040] Figure 3 This is the second structural block diagram of the control circuit provided in the embodiment of the present application;

[0041] Figure 4 This is the third structural block diagram of the control circuit provided in the embodiment of the present application;

[0042] Figure 5 This is the second structural diagram of the display panel provided in the embodiment of the present application;

[0043] Figure 6 This is the fourth structural block diagram of the control circuit provided in the embodiment of the present application.

[0044] Reference numerals:

[0045] Array substrate 100, pixel unit 110, GOA circuit 120, power circuit 130, data circuit 140, integrated power management unit 150;

[0046] Control circuit 200 , detection circuit 210 , first comparison circuit 211 , first calculation circuit 212 , sampling circuit 213 , first reference circuit 214 , second comparison circuit 215 , second calculation circuit 216 , second reference circuit 217 , main control circuit 220 , switching circuit 230 . DETAILED DESCRIPTION

[0047] The following describes in detail embodiments of the present application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application.

[0048] The following description relates to elements or components that are "connected" or "coupled" together. As used herein, "connection" may refer to the mechanical coupling of one element / component to (or direct communication with) another element / component, and does not necessarily have to be direct. Similarly, "coupling" may refer to the direct or indirect coupling of one element / component to (or direct or indirect communication with) another element / component, and does not necessarily have to be mechanical. However, it should be understood that although in one embodiment, two elements are described below as "connected", similar elements may be "coupled" in alternative embodiments, and vice versa. Therefore, although the schematic diagrams shown herein describe exemplary arrangements of elements, additional intermediate elements, devices, components or members may still exist in an actual embodiment.

[0049] In the description, the terms "first," "second," etc. are used to distinguish similar objects, not to describe a particular order or precedence. It should be understood that the numerical descriptors used in this manner are interchangeable where appropriate, so that the embodiments of the present application can be implemented in an order other than that illustrated or described herein, and that the objects distinguished by "first," "second," etc. are generally of a class and do not limit the number of objects; for example, the first object can be one or more. In addition, the term "and / or" in the specification and claims refers to at least one of the connected objects, and the character " / " generally indicates that the objects connected are in an "or" relationship.

[0050] In addition, descriptions with reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" mean that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the exemplary expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples.

[0051] Reference Figure 1 , one embodiment of the present application provides a display panel.

[0052] The display panel includes an array substrate 100 and a control circuit board (not shown). The control circuit board and the array substrate 100 can be connected using an FPC. The array substrate 100 is provided with pixel units 110 and a GOA circuit 120. The control circuit board is provided with a main control circuit, which is electrically connected to the GOA circuit 120. The main control circuit can transmit control signals to the GOA circuit 120, causing the GOA circuit to drive the pixel units. The control signals can include STV signals, CLK signals, etc.

[0053] The main control circuit includes a power supply circuit 130, which provides a turn-on voltage VGH and a turn-off voltage VGL for the GOA circuit 120, as well as a data voltage for the data circuit 140. The GOA circuit 120 outputs a turn-on voltage VGH to the gate of the TFT within the pixel unit 110, turning the TFT on and a turn-off voltage VGL to the gate of the TFT, turning the TFT off. When the TFT is on, the data circuit 140 outputs a data voltage corresponding to the displayed image, which charges the pixel through the TFT. The display structure and principles of display panels are well-established technologies and will not be elaborated on in this embodiment.

[0054] Due to panel aging or low-temperature conditions, the activity of TFT materials decreases, requiring higher turn-on voltages (VGH) and turn-off voltages (VGL). The turn-off voltage (VGL) is usually described as a negative voltage, with a higher VGL indicating a higher absolute value. For example, if the turn-off voltage (VGL) is -8V, then a higher turn-off voltage (VGL) could be -10V.

[0055] In the related art, to cope with low-temperature startup, a thermistor is often added to the control circuit board to detect the ambient temperature and compensate the drive voltage of the GOA circuit 120 accordingly. The drive voltage includes the turn-on voltage VGH and the turn-off voltage VGL. However, due to the heat generated by the control circuit board itself and the backlight heating, there is a difference between the temperature detected by the thermistor and the ambient temperature, making this compensation solution ineffective.

[0056] To this end, the present application provides a control circuit for a display panel, which detects the output signal of the GOA circuit to determine the driving capability of the GOA circuit, and then dynamically adjusts the turn-on voltage provided by the power supply circuit to the GOA circuit to ensure that the GOA circuit can turn on the TFT, thereby avoiding aging caused by continuous use of high voltage.

[0057] In some embodiments, the control circuit 200 of the display panel may be disposed on a control circuit board.

[0058] Reference Figure 2In some embodiments, the control circuit 200 of the display panel includes a detection circuit 210 and a main control circuit 220. The detection circuit 210 is coupled to the GOA circuit 120 and configured to detect the output signal of the GOA circuit 120 and provide a first parameter, which characterizes the voltage rising speed of the output signal; the main control circuit 220 is coupled to the detection circuit 210 and the power supply circuit 130 respectively, and is configured to determine the target turn-on voltage based on the first parameter and the reference parameter, and control the power supply circuit 130 to provide the target turn-on voltage to the GOA circuit 120.

[0059] The output signal of the GOA circuit 120 is generally referred to as a scan signal, and its potential periodically switches between a high level and a low level. When the output signal of the GOA circuit 120 is at a high level, the voltage is a turn-on voltage VGH, and when it is at a low level, the voltage is a turn-off voltage VGL.

[0060] The GOA circuit 120 is typically composed of multiple TFT structures, such as a 4T1C or 8T1C structure. Therefore, the GOA circuit 120 itself is also affected by the reduced activity of the TFT materials in low-temperature environments. Similarly, the GOA circuit is also affected by aging. The basic structure of the GOA circuit 120 is a mature technology and will not be detailed in this embodiment.

[0061] It should be noted that when the GOA circuit 120 needs to turn on the TFT, the voltage of the output signal switches from the off voltage VGL to the on voltage VGH. During the switching process, the voltage of the output signal gradually rises. The faster the voltage rise rate of the output signal, the less time it takes for the voltage of the output signal to rise from the off voltage VGL to the on voltage VGH. The slower the voltage rise rate of the output signal, the more time it takes. As the activity of the TFT material decreases, the voltage rise rate of the output signal of the GOA circuit 120 slows down. Therefore, by detecting the voltage rise rate, the current driving capability of the GOA circuit 120 can be determined.

[0062] In some embodiments, the GOA circuit 120 includes multiple cascaded GOA units, and the detection circuit 210 can be coupled to the output of the GOA unit closest to the control circuit board to detect the output signal. Since the GOA circuit 120 generally starts driving the GOA unit farthest from the control circuit board, the detection circuit 210 can be coupled to the output of the last-stage GOA unit. Since the detection circuit 210 is provided on the control circuit board, wiring costs can be reduced by connecting to the nearest GOA unit.

[0063] It should be noted that the reference parameter is used to characterize the ideal voltage climbing speed of the output signal. When the GOA circuit 120 provides an output signal at the ideal voltage climbing speed, it can ensure that the TFT is turned on according to the expected turn-on time. If the voltage climbing speed represented by the first reference is less than the ideal voltage climbing speed, it means that the driving voltage of the GOA circuit 120 is too low. At this time, the driving voltage of the GOA circuit 120 can be increased. If the current turn-on voltage VGH of the GOA circuit is 24V, 25V can be used as the target turn-on voltage. This ensures that the GOA circuit can turn on the TFT normally.

[0064] If the voltage climbing speed represented by the first reference is greater than the ideal voltage climbing speed, it means that the driving voltage of the GOA circuit 120 is too high. In this case, the driving voltage of the GOA circuit 120 can be reduced. If the current turn-on voltage VGH of the GOA circuit is 28V, 27V can be used as the target turn-on voltage. This can prevent the excessive turn-on voltage VGH from accelerating aging.

[0065] In this embodiment, the main control circuit 220 can communicate with the power circuit 130 via I2C. The main control circuit 220 sends information about the target turn-on voltage to the power circuit 130. The power circuit 130 adjusts the voltage output and provides the target turn-on voltage to the GOA circuit 120. The voltage conversion structure and principle of the power circuit 130 are already mature technologies and will not be described in detail in this embodiment.

[0066] It should be noted that to ensure the panel can boot up normally, the main control circuit 220 can set a default startup voltage VGHD. VGHD is set higher here to take into account the higher voltage required for low-temperature startup. The main control circuit 220 controls the power supply circuit 130 to provide VGHD to the GOA circuit 120, enabling the pixel unit to start up. Subsequently, the main control circuit 220 adjusts the startup voltage provided by the power supply circuit 130 to the GOA circuit 120 based on the first parameter feedback from the detection circuit 210.

[0067] According to the control circuit 200 of the present application, the output signal of the GOA circuit 120 is detected to determine the driving capability of the GOA circuit 120, and then the turn-on voltage provided by the power supply circuit 130 to the GOA circuit 120 is dynamically adjusted to ensure that the GOA circuit 120 can turn on the TFT, thereby avoiding aging caused by continuous use of high voltage.

[0068] In some embodiments, the first parameter includes a first time parameter for the voltage of the output signal to rise from the first voltage to the second voltage, and / or a second time parameter for the output signal to remain greater than or equal to a third voltage.

[0069] It should be noted that the first and second voltages are greater than or equal to the cutoff voltage VGL and less than or equal to the cutoff voltage VGH. The process of the output signal voltage switching from the cutoff voltage VGL to the cutoff voltage VGH includes a period of rising from the first voltage to the second voltage. Therefore, the first time parameter for the output signal voltage to rise from the first voltage to the second voltage can reflect the voltage rise speed. The larger the first time parameter, the slower the voltage rise speed; the smaller the first time parameter, the faster the voltage rise speed.

[0070] The third voltage is greater than or equal to the turn-off voltage VGL and less than or equal to the turn-on voltage VGH. Since the scanning time of the TFT within one frame time is constant, the voltage of the output signal will remain until the end of the frame time after exceeding the third voltage. Taking the third voltage as the turn-on voltage VGH as an example, the state in which the output signal remains greater than or equal to the third voltage can represent the turn-on time of the TFT. Since the scanning time of the TFT within one frame time is constant, the faster the voltage of the output signal reaches the third voltage, the longer the turn-on time of the TFT. Therefore, the second time parameter in which the output signal remains greater than or equal to the third voltage can also reflect the voltage rise speed. The larger the second time parameter, the faster the voltage rise speed; the smaller the second time parameter, the slower the voltage rise speed.

[0071] In some embodiments, the detection circuit 210 can detect the first time parameter and the second time parameter simultaneously, and the main control circuit 220 determines the corresponding turn-on voltage according to the first time parameter and the second time parameter, and then selects the target turn-on voltage from the determined turn-on voltages.

[0072] As an example, if it is determined according to the first time parameter to maintain the current turn-on voltage of the GOA circuit 120, and it is determined according to the second time parameter to increase the current turn-on voltage of the GOA circuit 120, the control power supply circuit 130 provides the GOA circuit 120 with a target turn-on voltage determined according to the second time parameter.

[0073] Reference Figure 3 In some embodiments, the first parameter includes a first time parameter, and the detection circuit 210 includes a first comparison circuit 211 and a first calculation circuit 212. The first comparison circuit 211 is configured to provide a first comparison signal when the first sampling voltage is greater than or equal to the first voltage and less than or equal to the second voltage, and the first sampling voltage represents the voltage value of the output signal; the first calculation circuit 212 is coupled to the first comparison circuit 211 and is configured to determine the first time parameter based on the first comparison signal.

[0074] In this embodiment, the detection circuit 210 may further include a sampling circuit 213 , which is coupled to the GOA circuit 120 and the first comparison circuit 211 , respectively, for sampling the output signal of the GOA circuit 120 and providing a first sampling voltage.

[0075] In some embodiments, the sampling circuit 213 may include a voltage-dividing resistor unit that converts the voltage of the output signal of the GOA circuit 120 into a first sampling voltage by means of a voltage divider. This reduces the high voltage range between the turn-off voltage VGL and the turn-on voltage VGH to a voltage range acceptable to subsequent circuits. Furthermore, to avoid attenuation caused by voltage division, a compensation capacitor may be connected in parallel to the voltage-dividing resistor unit.

[0076] As an example, the first comparison circuit 211 may include a first comparator A1, a second comparator A2, and an AND gate AN. The positive input of the first comparator A1 and the negative input of the second comparator A2 are connected to the first sampling voltage, the negative input of the first comparator A1 is connected to the first voltage, and the positive input of the second comparator A2 is connected to the second voltage. The output of the first comparator A1 and the output of the second comparator A2 are respectively connected to the two output terminals of the AND gate AN.

[0077] In this example, if the first sampled voltage is greater than or equal to the first voltage, the first comparator A1 outputs a high level. If the first sampled voltage is less than or equal to the second voltage, the second comparator A2 outputs a high level. AND gate AN outputs a high level when both the first comparator A1 and the second comparator A2 output a high level. The duration that AND gate AN outputs a high level is equal to the time it takes for the first sampled voltage, and thus the first voltage, to rise to the second voltage.

[0078] In some embodiments, the first calculation circuit 212 may include a crystal oscillator and a counter. The crystal oscillator is used to generate a clock signal. The counter receives the clock signal and the output signal of the AND gate AN. When the AND gate AN outputs a high level, the counter counts under the drive of the clock signal. The count result of the counter is the time when the AND gate AN outputs a high level, and the count result can be used as the first time parameter.

[0079] In some embodiments, the detection circuit 210 further includes a first reference circuit 214 configured to generate a first voltage and a second voltage according to a first coefficient, a second coefficient, and a current turn-on voltage of the GOA circuit 120 , wherein the first coefficient is smaller than the second coefficient.

[0080] As an example, the first reference circuit 214 may be connected to the first comparator A1 and the second comparator A2 respectively to provide a first voltage and a second voltage.

[0081] In this embodiment, to ensure that the first time parameter effectively reflects the voltage ramp rate of the output signal of the GOA circuit 120, the current threshold voltage of the GOA circuit 120 is used as a reference to determine the first voltage and the second voltage. Furthermore, after the threshold voltage of the GOA circuit 120 is adjusted, the first voltage and the second voltage are also adjusted accordingly.

[0082] In some embodiments, the first reference circuit 214 may provide a reference voltage according to the following formula:

[0083] Vref=VGL+K*(VGH-VGL)

[0084] K is a coefficient of the reference voltage, which can be set as needed. For example, the first coefficient K1 can be 0.1, then the first voltage Vref1 = VGL + 0.1 * (VGH - VGL); the second coefficient K2 can be 0.9, then the second voltage Vref2 = VGL + 0.9 * (VGH - VGL).

[0085] Reference Figure 4 In some embodiments, the first parameter includes a second time parameter, the detection circuit includes a second comparison circuit 215 and a second calculation circuit 216, the second comparison circuit 215 is configured to provide a second comparison signal when the second sampling voltage is greater than or equal to the third voltage, and the second sampling voltage represents the voltage value of the output signal; the second calculation circuit 216 is coupled to the second comparison circuit 215 and configured to determine the second time parameter based on the second comparison signal.

[0086] In this embodiment, the detection circuit 210 may also include a sampling circuit 213. The sampling circuit 213 is used to provide a second sampling voltage. The structure and principle of the sampling circuit 213 may refer to the above.

[0087] As an example, the second comparison circuit 215 may include a third comparator A3, wherein the second sampled voltage is connected to the positive input terminal of the third comparator A3, and the third voltage is connected to the negative input terminal of the third comparator A3. If the second sampled voltage is greater than or equal to the third voltage, the third comparator A3 outputs a high level. That is, the third comparator A3 outputs a high level for a period of time equal to the time the second sampled voltage remains greater than or equal to the third voltage.

[0088] In some embodiments, the second calculation circuit 216 may also include a crystal oscillator and a counter, which receives the clock signal and the output signal of the third comparator A3. When the third comparator A3 outputs a high level, the counter counts under the drive of the clock signal. The count result of the counter is the time when the third comparator A3 outputs a high level, and the count result can be used as the second time parameter.

[0089] In some embodiments, the detection circuit 210 further includes a second reference circuit 217 configured to generate a third voltage according to a third coefficient and a current turn-on voltage of the GOA circuit 120 .

[0090] As an example, the second reference circuit 217 can be connected to the negative input terminal of the third comparator A3 to provide the first voltage and the second voltage. Similarly, the second reference circuit 217 can provide the reference voltage according to the following formula:

[0091] Vref=VGL+K*(VGH-VGL)

[0092] K is a coefficient of the reference voltage, which can be set according to requirements. For example, the third coefficient K3 can be 0.9, and the third voltage Vref3 = VGL + 0.9 * (VGH - VGL).

[0093] In some embodiments, the reference parameter includes a target range; the main control circuit 220 is configured to control the power supply circuit 130 to maintain the current start-up voltage when the first parameter is within the target range; the main control circuit 200 is configured to control the power supply circuit 130 to reduce or increase the current start-up voltage when the first parameter is outside the target range.

[0094] In this embodiment, in order to facilitate control and avoid frequent fluctuations in the turn-on voltage, a target range is set and compared with the first parameter to determine whether the current turn-on voltage needs to be adjusted. When the first parameter is within the target range, it indicates that the current turn-on of the GOA circuit 120 is reasonable and can remain unchanged. When the first parameter is outside the target range, it indicates that the current turn-on of the GOA circuit 120 is unreasonable, and it is necessary to reduce or increase the current turn-on voltage based on the relationship between the first parameter, the GOA circuit 120, and the voltage climbing speed.

[0095] As an example, the first parameter may be the aforementioned first time parameter, which is negatively correlated with the voltage climbing speed. That is, the larger the value of the first time parameter is, the slower the voltage climbing speed is. Tr represents the first time parameter, and TR represents the voltage climbing speed. B ~TR T Indicates the target range, TR B is the minimum value of the target range, TR T As the maximum value of the target range, the process of the main control circuit 220 determining the current start voltage can be:

[0096] If Tr is less than TR B , the main control circuit 220 determines the target turn-on voltage according to the step size of VGH1=VGH2-1V, wherein VGH1 is the target turn-on voltage and VGH2 is the current turn-on voltage of the GOA circuit 120, until Tr is in TR B ~TRT If Tr is greater than TR T , the main control circuit 220 determines the target turn-on voltage according to the step size of VGH1=VGH2+1V, wherein VGH1 is the target turn-on voltage and VGH2 is the current turn-on voltage of the GOA circuit 120, until Tr is in TR B ~TR T between.

[0097] As another example, the first parameter may be the aforementioned second time parameter, which is positively correlated with the voltage climbing speed. That is, the larger the value of the second time parameter, the faster the voltage climbing speed. Th represents the second time parameter, and TH represents the voltage climbing speed. B ~TH T Indicates the target range, TH B is the minimum value of the target range, TH T As the maximum value of the target range, the process of the main control circuit 220 determining the current start voltage can be:

[0098] If Th is less than TH B , the main control circuit 220 determines the target turn-on voltage according to the step size of VGH1=VGH2+1V, wherein VGH1 is the target turn-on voltage and VGH2 is the current turn-on voltage of the GOA circuit 120, until Th is at TH B ~TH T If Th is greater than TH T , the main control circuit 220 determines the target turn-on voltage according to the step size of VGH1=VGH2-1V, wherein VGH1 is the target turn-on voltage and VGH2 is the current turn-on voltage of the GOA circuit 120, until Th is at TH B ~TH T between.

[0099] In some embodiments, the reference parameter includes a first reference range and a second reference range. When the first parameter changes in an upward trend, the first reference range is used as the target range. When the first parameter changes in a downward trend, the second reference range is used as the target range.

[0100] In this embodiment, the first reference range and the second reference range are two different ranges, but the difference between their values ​​can be small. Since the first parameter is prone to up and down jitter and jump near the extreme value of the threshold range, setting two reference ranges can avoid this problem.

[0101] As an example, the first parameter may be a first time parameter Tr, and the first reference range may be set to TR B1 ~TR T1 , set the second reference range to TR B2 ~TR T2If Tr is larger than the previous Tr, use TR B1 ~TR T1 As the target range, if Tr is smaller than the previous Tr, use TR B2 ~TR T2 The same applies when the first parameter is the second time parameter Th.

[0102] Reference Figure 5 In some embodiments, the GOA circuit 120 includes a first GOA circuit 121 and a second GOA circuit 122 arranged on both sides of the pixel unit 110, and the control circuit 200 further includes a switching circuit 230, which is coupled to the first GOA circuit 121, the second GOA circuit 122 and the detection circuit 210 respectively, and is configured to selectively connect the detection circuit 210 to the first GOA circuit 121, or connect the detection circuit 210 to the second GOA circuit 122.

[0103] For larger panels, the pixel unit 110 typically uses a bilateral GOA drive. In actual use, the aging degree of the GOA circuits 120 on both sides is different. Therefore, this embodiment provides a switching circuit 230 to detect the output signals of the first GOA circuit 121 and the second GOA circuit 122 separately.

[0104] In some embodiments, the switching circuit 230 may include two switching transistors, each of which controls a path between the detection circuit 210 and the corresponding GOA circuit 120. For example, the first switching transistor is used to control the connection between the detection circuit 210 and the first GOA circuit 121, and the second switching transistor is used to control the connection between the detection circuit 210 and the second GOA circuit 122.

[0105] The switching circuit 230 can be coupled to the host circuit 220. The host circuit 220 can control the switching circuit 230 to switch at a certain frequency, that is, the first switch transistor and the second switch transistor are switched on and off at a certain frequency. Considering that the ambient temperature changes and the screen aging are relatively slow, the frequency can be set as needed, such as 10 minutes or 1 hour.

[0106] In some embodiments, since the first GOA circuit 121 and the second GOA circuit 122 are generally driven by the same turn-on voltage VGH, if the first GOA circuit 121 and the second GOA circuit 122 require different degrees of compensation, the first GOA circuit 121 and the second GOA circuit 122 are controlled according to the target turn-on voltage with the highest degree of compensation.

[0107] As an example, if the first target turn-on voltage determined according to the output signal of the first GOA circuit 121 is greater than the current turn-on voltage, and the second target turn-on voltage determined according to the output signal of the second GOA circuit 122 is greater than or equal to the turn-on voltage, then the first GOA circuit 121 and the second GOA circuit 122 are driven according to the first target turn-on voltage, that is, the main control circuit 220 controls the power supply circuit 130 to provide the first target turn-on voltage to both the first GOA circuit 121 and the second GOA circuit 122.

[0108] In this embodiment, the first GOA circuit 121 and the second GOA circuit 122 can be detected by using one detection circuit 210 and a main control circuit 220 , thereby reducing costs.

[0109] In some embodiments, the main control circuit 220 is further configured to determine a target turn-off voltage according to the first parameter and the reference parameter, and control the power supply circuit 130 to provide the target turn-off voltage to the GOA circuit 120 .

[0110] In this embodiment, in order to further ensure that the GOA circuit 120 can effectively turn off the TFT, the turn-off capability of the GOA circuit 120 is improved by dynamically adjusting the turn-off voltage.

[0111] In some embodiments, the main control circuit 220 can adjust the turn-on voltage and the turn-off voltage simultaneously, with the turn-off voltage and the turn-on voltage adjusted in the same direction. That is, when the turn-on voltage needs to be increased, the turn-off voltage is also increased. Increasing the turn-off voltage means increasing the absolute value of the turn-off voltage.

[0112] As an example, assume that the current turn-on voltage of the GOA circuit 120 is 26V and the current turn-off voltage is -8V; if it is determined based on the first parameter and the reference parameter that the turn-on voltage and the turn-off voltage need to be increased, the target turn-on voltage can be 27V and the target turn-off voltage can be -9V; if it is determined based on the first parameter and the reference parameter that the turn-on voltage and the turn-off voltage need to be reduced, the target turn-on voltage can be 25V and the target turn-off voltage can be -7V.

[0113] Reference Figure 6 An embodiment of the present application also provides a display panel, in which the control circuit board is provided with an integrated power management unit 150 and a timing control unit, the detection circuit 210 and the power circuit 130 in the control circuit 200 are integrated in the integrated power management unit 150, and the main control circuit 220 in the control circuit 200 is integrated in the timing control unit.

[0114] The integrated power management unit 150 (PMIC, Power Management IC) is used to manage the power supply of each module in the display panel. Figure 6The circuit structure of the integrated power management unit 150 is shown. The detection circuit 210 is primarily an analog circuit and can therefore be integrated within the integrated power management unit 150. The main control circuit 220 is primarily a digital circuit and can therefore be integrated within the timing control unit. This reduces costs and simplifies peripheral circuits.

[0115] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and intent of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A control circuit for a display panel, characterized in that: The display panel includes a GOA circuit, a power supply circuit, and a pixel unit. The GOA circuit is configured to control the pixel unit to turn on using a turn-on voltage provided by the power supply circuit. The control circuit includes: a detection circuit coupled to the GOA circuit and configured to detect an output signal of the GOA circuit and provide a first parameter, wherein the first parameter represents a voltage rise speed of the output signal; a main control circuit, coupled to the detection circuit and the power supply circuit, respectively, and configured to determine a target turn-on voltage according to the first parameter and a reference parameter, and control the power supply circuit to provide the target turn-on voltage to the GOA circuit, wherein the reference parameter represents an ideal voltage climbing speed of the output signal; When the voltage climbing speed is greater than the ideal voltage climbing speed, the target turn-on voltage is less than the current turn-on voltage; when the voltage climbing speed is less than the ideal voltage climbing speed, the target turn-on voltage is greater than the current turn-on voltage.

2. The control circuit according to claim 1, wherein: The first parameter includes a first time parameter for the voltage of the output signal to rise from the first voltage to the second voltage, and / or a second time parameter for the output signal to maintain a state greater than or equal to a third voltage.

3. The control circuit according to claim 2, characterized in that: The first parameter includes the first time parameter, and the detection circuit includes: a first comparison circuit configured to provide a first comparison signal when a first sampling voltage is greater than or equal to the first voltage and less than or equal to the second voltage, wherein the first sampling voltage represents a voltage value of the output signal; The first calculation circuit is coupled to the first comparison circuit and configured to determine a first time parameter according to the first comparison signal.

4. The control circuit according to claim 3, characterized in that: The detection circuit further includes: The first reference circuit is configured to generate the first voltage and the second voltage according to a first coefficient, a second coefficient, and a current turn-on voltage of the GOA circuit, wherein the first coefficient is smaller than the second coefficient.

5. The control circuit according to claim 2, wherein: The first parameter includes the second time parameter, and the detection circuit includes: a second comparison circuit configured to provide a second comparison signal when the second sampling voltage is greater than or equal to a third voltage, wherein the second sampling voltage represents a voltage value of the output signal; The second calculation circuit is coupled to the second comparison circuit and configured to determine a second time parameter according to the second comparison signal.

6. The control circuit according to claim 5, characterized in that: The detection circuit further includes: The second reference circuit is configured to generate the third voltage according to a third coefficient and a current turn-on voltage of the GOA circuit.

7. The control circuit according to any one of claims 1 to 6, characterized in that: The reference parameters include target ranges; The main control circuit is configured to control the power supply circuit to maintain a current start-up voltage when the first parameter is within the target range; The main control circuit is configured to control the power supply circuit to reduce or increase a current start-up voltage when the first parameter is outside the target range.

8. The control circuit according to claim 7, characterized in that: The reference parameter includes a first reference range and a second reference range. When the first parameter changes in an upward trend, the first reference range is used as a target range. When the first parameter changes in a downward trend, the second reference range is used as a target range.

9. The control circuit according to claim 7 or 8, characterized in that: The first parameter is positively correlated with the voltage climbing speed; The main control circuit is configured to control the power supply circuit to reduce the current start-up voltage when the first parameter is less than the minimum value of the target range; The main control circuit is configured to control the power supply circuit to increase a current start-up voltage when the first parameter is greater than a maximum value of the target range.

10. The control circuit according to claim 7 or 8, characterized in that: The first parameter is negatively correlated with the voltage climbing speed; The main control circuit is configured to control the power supply circuit to increase the current start-up voltage when the first parameter is less than the minimum value of the target range; The main control circuit is configured to control the power supply circuit to reduce a current start-up voltage when the first parameter is greater than a maximum value of the target range.

11. The control circuit according to any one of claims 1 to 6, characterized in that: The GOA circuit includes a first GOA circuit and a second GOA circuit provided on both sides of the pixel unit, and the control circuit further includes: The switching circuit is coupled to the first GOA circuit, the second GOA circuit and the detection circuit respectively, and is configured to selectively connect the detection circuit to the first GOA circuit or connect the detection circuit to the second GOA circuit.

12. The control circuit according to any one of claims 1 to 6, characterized in that: The main control circuit is further configured to determine a target turn-off voltage according to the first parameter and the reference parameter, and control the power supply circuit to provide the target turn-off voltage to the GOA circuit.

13. A display panel, characterized in that: The invention comprises an array substrate and a control circuit board, wherein the array substrate is provided with a pixel unit and a GOA circuit, and the control circuit board is provided with a power supply circuit and a control circuit according to any one of claims 1 to 12.

14. The display panel according to claim 13, wherein: The control circuit board is provided with an integrated power management unit and a timing control unit. The detection circuit and the power circuit in the control circuit are integrated into the integrated power management unit, and the main control circuit in the control circuit is integrated into the timing control unit.

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