Gamma circuit and display panel

Abstract

The embodiment of the present application discloses a gamma circuit and a display panel, comprising a voltage output module, the voltage output module is used for outputting first gamma voltage, second gamma voltage, third gamma voltage and fourth gamma voltage according to received power voltage, the first gamma voltage, the second gamma voltage, the third gamma voltage and the fourth gamma voltage are used as reference voltage to adjust the gray scale value of data signal, the data signal is used for controlling the pixel unit of display area to carry out image display. The gamma circuit further comprises a voltage adjustment module, the voltage adjustment module is electrically connected to the voltage output module and the data driving circuit, the voltage adjustment module is used for adjusting the voltage difference between the first gamma voltage and the second gamma voltage within the preset range, adjusting the voltage difference between the third gamma voltage and the fourth gamma voltage within the preset range, so as to eliminate the horizontal crosstalk phenomenon caused by the appearance of the power voltage.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display, in particular to a gamma circuit and a display panel. BACKGROUND

[0002] At present, when a large-size display panel displays an image, a Crosstalk phenomenon often occurs, that is, parallel horizontal lines appear on a white frame. This kind of Crosstalk phenomenon is mainly caused by the voltage drop of AVDD voltage when the data voltage changes from low to high, which leads to the voltage drop of AVDD voltage. Since the AVDD voltage is the input power supply of the gamma circuit, the voltage drop of AVDD also leads to the voltage drop of the gamma voltage. The data driving circuit generates a data signal according to the gamma voltage and outputs the data signal to a data line. The data voltage signal is output to each sub-pixel through the data line to control the brightness of each pixel. Since the voltage drops of the positive and negative gamma voltages are inconsistent, the changes of the positive and negative data signals are inconsistent, which leads to the inconsistency of the brightness of the pixel display, thereby causing the horizontal Crosstalk phenomenon. Therefore, how to adjust the gamma voltage to eliminate the horizontal Crosstalk phenomenon is a problem to be solved. SUMMARY

[0003] In view of the above problems of the prior art, the present application provides a gamma circuit and a display panel which can effectively eliminate the horizontal Crosstalk phenomenon.

[0004] The present application provides a gamma circuit, which comprises a voltage output module. The voltage output module is configured to output a first gamma voltage, a second gamma voltage, a third gamma voltage and a fourth gamma voltage according to a received power voltage. The first gamma voltage, the second gamma voltage, the third gamma voltage and the fourth gamma voltage are used as reference voltages to adjust the gray scale value of a data signal. The data signal is used to control a pixel unit of a display area to display an image. The gamma circuit further comprises a voltage adjustment module electrically connected to the voltage output module and a data driving circuit. The voltage adjustment module is configured to adjust the voltage difference between the first gamma voltage and the second gamma voltage to be within a preset range and adjust the voltage difference between the third gamma voltage and the fourth gamma voltage to be within a preset range.

[0005] Optionally, the first gamma voltage and the third gamma voltage are positive reference voltages used to adjust the gray scale value of a positive data signal, wherein the first gamma voltage is greater than the third gamma voltage. The second gamma voltage and the fourth gamma voltage are negative reference voltages used to adjust the gray scale value of a negative data signal, wherein the second gamma voltage is less than the fourth gamma voltage. The first gamma voltage and the second gamma voltage are symmetrical about a center reference voltage, and the third gamma voltage and the fourth gamma voltage are symmetrical about the center reference voltage.

[0006] Optionally, the voltage adjustment module comprises a first adjustment unit, a second adjustment unit, a third adjustment unit and a fourth adjustment unit, the first adjustment unit is electrically connected to the first gamma voltage output end, used for receiving the first gamma voltage and transmitting the first gamma voltage to the data driving circuit after adjustment; the second adjustment unit is electrically connected to the second gamma voltage output end, used for receiving the second gamma voltage and transmitting the second gamma voltage to the data driving circuit after adjustment; the third adjustment unit is electrically connected to the third gamma voltage output end, used for receiving the third gamma voltage and transmitting the third gamma voltage to the data driving circuit after adjustment; the fourth adjustment unit is electrically connected to the fourth gamma voltage output end, used for receiving the fourth gamma voltage and transmitting the fourth gamma voltage to the data driving circuit after adjustment.

[0007] Optionally, the first adjustment unit comprises a first resistor and a first capacitor, a first end of the first resistor is electrically connected to the first gamma voltage output end, a second end of the first resistor is electrically connected to the data driving circuit, a first end of the first capacitor is electrically connected to the second end of the first resistor, and a second end of the first capacitor is electrically connected to the ground end. The second adjustment unit comprises a second resistor and a second capacitor, a first end of the second resistor is electrically connected to the second gamma voltage output end, a second end of the second resistor is electrically connected to the data driving circuit, a first end of the second capacitor is electrically connected to the second end of the second resistor, and a second end of the second capacitor is electrically connected to the ground end; wherein the resistance value of the first resistor is greater than the resistance value of the second resistor, and the capacitance value of the first capacitor is greater than or equal to the capacitance value of the second capacitor.

[0008] Optionally, the third adjustment unit comprises a third resistor and a third capacitor, a first end of the third resistor is electrically connected to the third gamma voltage output end, a second end of the third resistor is electrically connected to the data driving circuit, a first end of the third capacitor is electrically connected to the second end of the third resistor, and a second end of the third capacitor is electrically connected to the ground end; the fourth adjustment unit comprises a fourth resistor and a fourth capacitor, a first end of the fourth resistor is electrically connected to the fourth gamma voltage output end, a second end of the fourth resistor is electrically connected to the data driving circuit, a first end of the fourth capacitor is electrically connected to the second end of the fourth resistor, and a second end of the fourth capacitor is electrically connected to the ground end; wherein the resistance value of the third resistor is equal to the resistance value of the fourth resistor, and the capacitance value of the third capacitor is equal to the capacitance value of the fourth capacitor.

[0009] Optionally, the voltage adjustment module further comprises a detection unit, the detection unit is electrically connected to the second adjustment unit, when the detection unit detects that the power voltage drop value is less than or equal to a preset threshold value, the detection unit outputs a first control signal to the second adjustment unit to control the second adjustment unit to adjust to a first preset resistance-capacitance, when the detection unit detects that the power voltage drops to greater than the preset threshold value, the detection unit outputs a second control signal to the second adjustment unit to control the second adjustment unit to adjust to a second preset resistance-capacitance.

[0010] Optionally, the second adjusting unit comprises a first adjusting control component and a second adjusting control component, when the detecting unit outputs the first control signal, the first adjusting component receives the second gamma voltage and transmits to the data driving circuit, when the detecting unit outputs the second control signal, the second adjusting component receives the second gamma voltage and transmits to the data driving circuit.

[0011] Optionally, the first adjusting component comprises a first switch tube, a fifth resistor and a fifth capacitor, the control end of the first switch tube is electrically connected to the detecting unit, the first end of the first switch tube is electrically connected to the second gamma voltage output end, the second end of the first switch tube is electrically connected to the first end of the fifth resistor, the second end of the fifth resistor is electrically connected to the data driving circuit, the first end of the fifth capacitor is electrically connected to the second end of the fifth resistor, and the second end of the fifth capacitor is electrically connected to the ground, wherein the resistance value of the fifth resistor is less than or equal to the resistance value of the first resistor, and the capacitance value of the fifth capacitor is less than or equal to the capacitance value of the first capacitor.

[0012] Optionally, the second adjusting component comprises a second switch tube, a sixth resistor and a sixth capacitor, the control end of the second switch tube is electrically connected to the detecting unit, the first end of the second switch tube is electrically connected to the second gamma voltage output end, the second end of the second switch tube is electrically connected to the first end of the sixth resistor, the second end of the sixth resistor is electrically connected to the data driving circuit, the first end of the sixth capacitor is electrically connected to the second end of the second resistor, and the second end of the sixth capacitor is electrically connected to the ground, wherein the resistance value of the sixth resistor is less than the resistance value of the fifth resistor, and the capacitance value of the sixth capacitor is less than or equal to the capacitance value of the fifth capacitor.

[0013] The application further provides a display panel comprising the aforementioned gamma circuit, a data driving circuit and a plurality of pixel units, the data driving circuit is used for outputting a plurality of data signals of different gray scales according to the first gamma voltage, the second gamma voltage, the third gamma voltage and the fourth gamma voltage output by the gamma circuit, and transmitting the data signals to the pixel units to drive the pixel units to display images.

[0014] Compared with the prior art, the application sets the voltage adjusting module, so that when the power voltage changes due to load change, the difference between the first gamma voltage and the second gamma voltage is maintained within a preset range, and the difference between the third gamma voltage and the fourth gamma voltage is maintained within a preset range, thereby eliminating the problem of horizontal crosstalk. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments. Obviously, the drawings described in the following are some embodiments of the application, and other drawings can also be obtained by those skilled in the art without any creative effort.

[0016] Figure 1 A structural schematic diagram of a display device provided in an embodiment of the present application is shown in FIG. 1.

[0017] Figure 2 A structural schematic diagram of a display panel provided in an embodiment of the present application is shown in FIG. 2. Figure 1

[0018] Figure 3 A structural schematic diagram of a gamma voltage generation logic provided in an embodiment of the present application is shown in FIG. 3. Figure 2

[0019] A structural schematic diagram of a gamma circuit and a data driving circuit provided in an embodiment of the present application is shown in FIG. 4. Figure 4 Figure 3 A structural schematic diagram of a gamma voltage variation provided in an embodiment of the present application is shown in FIG. 5.

[0020] Figure 5 A circuit block diagram of a gamma circuit provided in a second embodiment of the present application is shown in FIG. 6.

[0021] Figure 6 A circuit block diagram of a voltage adjustment module provided in an embodiment of the present application is shown in FIG. 7.

[0022] Figure 7 Figure 6 A structural schematic diagram of a second adjustment unit provided in a third embodiment of the present application is shown in FIG. 8.

[0023] Figure 8 A structural schematic diagram of a gamma voltage adjustment provided in an embodiment of the present application is shown in FIG. 9. Figure 7

[0024] Figure 9 Figure 8

[0025] Reference signs:

[0026] ​​​​​​Display device-100, display panel-10, power module-30, display area-10a, power management circuit-11, timing control circuit-12, gamma circuit-13, data drive circuit-14, scan drive circuit-15, pixel unit-P, power voltage-AVDD, analog working voltage-DVDD, VGL-off voltage, VGH-on voltage, clock signal-CLK, first gamma voltage-GM1, second gamma voltage-GM2, third gamma voltage-GM3, fourth gamma voltage-GM4, center reference voltage-GM0, data signal-Data, voltage output module-131, voltage adjustment module-132, first adjustment unit-132a, second adjustment unit-132b, third adjustment unit-132c, fourth adjustment unit-132d, detection unit-132e, first adjustment control component-b1, second adjustment control component-b2, data signal-Data, first switch tube-Q1, second switch tube-Q2, resistor-R, first resistor-R1, second resistor-R2, third resistor-R3, fourth resistor-R4, fifth resistor-R5, sixth resistor-R6, first capacitor-C1, second capacitor-C2, third capacitor-C3, fourth capacitor-C4, fifth capacitor-C5, sixth capacitor-C6, first period-t1, second period-t2, ground terminal-GND. DETAILED DESCRIPTION

[0027] For the purpose of promoting an understanding of the application, the application will now be described in greater detail with reference to the figures. The preferred embodiments of the application are illustrated in the figures. However, the application can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the application to those skilled in the art.

[0028] The following description of several embodiments with reference to the additional drawings is used to illustrate specific embodiments in which the application can be implemented. The serial numbers of the components in this paper, such as "first", "second", etc., are only used to distinguish the described objects, and have no technical meaning. The "connection" and "coupling" mentioned in this paper, unless otherwise specified, include direct and indirect connection (coupling). The direction of the terms mentioned in this paper, such as "up", "down", "front", "back", "left", "right", "inside", "outside", "side" and the like, are only the direction of the additional drawings, therefore, the direction of the terms used is to better, more clearly illustrate and understand the application, and is not indicative or implied that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore, it cannot be understood as a limitation on the application.

[0029] In the description of the present application, it should be noted that unless otherwise explicitly defined and limited, the terms "mounting", "connection", "connecting" should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integral connection; it can be mechanical connection; it can be direct connection, or indirect connection through intermediate medium; it can be internal connection of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances. It should be noted that the terms "first", "second" and the like in the description and claims of the present application and the drawings are used to distinguish different objects, and are not used to describe a specific order.

[0030] In addition, the terms "including", "may include", "comprising", or "may comprise" used in the present application represent the existence of the corresponding functions, operations, elements, etc. disclosed, and do not limit other one or more functions, operations, elements, etc. In addition, the terms "including" or "comprising" represent the existence of the corresponding features, numbers, steps, operations, elements, components or combinations thereof disclosed in the specification, and do not exclude the existence or addition of one or more other features, numbers, steps, operations, elements, components or combinations thereof, and are intended to cover non-exclusive inclusion. In addition, when describing the embodiments of the present application, "may" is used to represent "one or more embodiments of the present application". And the term "exemplary" is intended to refer to an example or illustration.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terms used in the specification of the present application are only for the purpose of describing the specific embodiments of the present application, and are not intended to limit the present application.

[0032] Please refer to Figure 1 , Figure 1 A structural schematic diagram of a display device provided in an embodiment of the present application is shown. As shown in Figure 1 , the display device 100 includes a display panel 10 and a power supply module 30, and the power supply module 30 is arranged on the back of the display panel 10, i.e. the non-display surface of the display panel 10. The power supply module 30 is used to provide power supply voltage for the display panel 10 to display images. In the embodiment of the present application, the display device 100 can be a portable electronic device, such as a mobile phone, a tablet computer, etc.

[0033] Please refer to Figure 2 , Figure 2 A schematic diagram of the planar layout of the display panel in Figure 1

[0034] As Figure 2 ​As shown, the display panel 10 comprises a power management circuit 11, a timing control circuit 12, a gamma circuit 13, a data driving circuit 14 and a scan driving circuit 15. The power management circuit 11 is electrically connected to the timing control circuit 12, the gamma circuit 13, the data driving circuit 14 and the scan driving circuit 15. The power management circuit 11 is configured to output a power voltage AVDD to the timing control circuit 12, the gamma circuit 13, the data driving circuit 14 and the scan driving circuit 15, and output an analog working voltage DVDD to the data driving circuit 14 and the scan driving circuit 15, so as to provide working voltages for the timing control circuit 12, the gamma circuit 13, the data driving circuit 14 and the scan driving circuit 15.

[0035] The timing control circuit 12 is configured to generate a clock signal CLK and data control signals and scan control signals (not labeled) according to an initial data signal received from outside and the power voltage AVDD provided by the power management circuit 11. The data control signals are configured to cooperate with the data driving circuit 14 to output data signals, and the clock signal CLK and the scan control signals are configured to cooperate with the scan driving circuit 15 to output scan signals.

[0036] The gamma circuit 13 is further electrically connected to the data driving circuit 14. The gamma circuit 13 is configured to generate a gamma voltage according to the received power voltage AVDD, and transmit the gamma voltage to the data driving circuit 14 under the control of the timing control circuit 12. The data driving circuit 14 is configured to take the gamma voltage as a reference voltage, generate voltages of all gray scales, i.e., data signals, according to the received power voltage AVDD and the analog working voltage DVDD, and transmit the required gray scale voltage to the pixel units P in the display area 10a, so as to control the pixel units P to display images.

[0037] The scan driving circuit 15 is configured to receive the power voltage AVDD, an on voltage VGH and an off voltage VGL from the power management circuit 11, and output scan signals to the pixel units P in the display area 10a according to the clock signal CLK and the on voltage VGH and the off voltage VGL. The pixel units P receive the data signals output by the data driving circuit 14 under the control of the scan signals.

[0038] Please refer to Figure 3 and Figure 4 , Figure 3 for Figure 2 the gamma voltage generation logic diagram in Figure 4 for Figure 3 the equivalent circuit diagram of the gamma circuit and the data driving circuit in

[0039] As Figure 3 and Figure 4As shown, the gamma circuit 13 outputs first, second, third and fourth gamma voltages GM1, GM2, GM3 and GM4 according to the power supply voltage AVDD, wherein the first and second gamma voltages GM1 and GM2 are the positive and negative voltages when the display panel 10 displays full white, i.e. corresponding to 255 gray scale, the third and fourth gamma voltages GM3 and GM4 are the positive and negative voltages when the display panel displays full black, i.e. corresponding to 0 gray scale, and other gray scales, i.e. 1-254 gray scales, are generated by the data driving circuit 14 according to the first to fourth gamma voltages GM1-GM4. The first and second gamma voltages GM1 and GM2 are symmetrical about the center reference voltage GM0, and the third and fourth gamma voltages GM3 and GM4 are symmetrical about the center reference voltage GM0.

[0040] Specifically, the gamma circuit 13 includes a plurality of resistors R connected in series for dividing the received power supply voltage AVDD by the plurality of resistors R into the required gamma voltages, i.e. the first to fourth gamma voltages GM1-GM4, and the data driving circuit 14 includes a plurality of resistors R connected in series for dividing the received gamma voltages by the plurality of resistors R to generate a plurality of different gray scale voltages, wherein 0 gray scale voltage to 255 gray scale voltage of positive polarity are generated according to the first and third gamma voltages GM1 and GM3, and 0 gray scale voltage to 255 gray scale voltage of negative polarity are generated according to the second and fourth gamma voltages GM2 and GM4, i.e. n data signals Data1-Datan are generated.

[0041] For example, taking the 64th gray scale as an example, the 64th gray scale of positive polarity is equal to (GM1-GM3)*(R1+R2+…R64) / Rt+GM3, and the 64th gray scale of negative polarity is equal to (GM4-GM2)*(R254+R253+…R64) / Rt+GM2, wherein R1+R2+…R64 represents 64 resistors R connected in series, R254+R253+…R64 represents 190 resistors R connected in series, and Rt represents the total resistance of the 254 resistors.

[0042] When the data voltage output by the data driving circuit 14 changes from low to high, the power management circuit 11 outputting the power supply voltage AVDD will experience a load change phenomenon, resulting in a voltage drop of the power supply voltage AVDD provided to the gamma circuit 13.

[0043] As shown in FIG. 1, the display panel 10 includes a plurality of pixels 20 arranged in a matrix form, and each pixel 20 includes a red sub-pixel 21, a green sub-pixel 22 and a blue sub-pixel 23. Figure 5 As shown in FIG. 1, the display panel 10 includes a plurality of pixels 20 arranged in a matrix form, and each pixel 20 includes a red sub-pixel 21, a green sub-pixel 22 and a blue sub-pixel 23. Figure 52 is a schematic diagram of gamma voltage changes. Since the power supply voltage AVDD is the input voltage of the gamma circuit 13, when the power supply voltage AVDD drops, the gamma voltage output by the gamma circuit 13 also drops. For example, the first gamma voltage GM1 and the second gamma voltage GM2 also drop, but the voltage drops of the first gamma voltage GM1 and the second gamma voltage GM2 are different. As a result, in the case of positive and negative polarity, the first gamma voltage GM1 and the second gamma voltage GM2 are asymmetric, which can cause lateral crosstalk on the display panel. It can be seen from the formula V=√(V1-cfvcom)2+(V2-CFCOM)2) / 2, where V1 and V2 are positive and negative polarity voltages at the same grayscale, respectively, and V is the pixel voltage of the combined positive and negative polarity driving liquid crystal. When V1 / V2 decreases simultaneously and the decrease amplitude is the same, the total pixel voltage V driving the liquid crystal changes less, thereby avoiding lateral crosstalk on the display panel.

[0044] Based on this, the present application provides a gamma circuit for eliminating the above-mentioned lateral crosstalk phenomenon.

[0045] See also Figure 6 , Figure 6 This is a circuit block diagram of a gamma circuit provided in the second embodiment of the present application.

[0046] like Figure 6 As shown, the gamma circuit 13 includes a voltage output module 131 and a voltage adjustment module 132. The voltage output module 131 is electrically connected to the voltage adjustment module 132, and the voltage adjustment module 132 is electrically connected to the data driving circuit 14. The voltage output module 131 is used to output the first gamma voltage GM1, the second gamma voltage GM2, the third gamma voltage GM3 and the fourth gamma voltage GM4 to the voltage adjustment module 132 according to the received power supply voltage AVDD. The voltage adjustment module 132 is used to adjust the received first gamma voltage GM1, the second gamma voltage GM2, the third gamma voltage GM3 and the fourth gamma voltage GM4 respectively to control the voltage difference between the first gamma voltage GM1 and the second gamma voltage GM2 within a preset range, and to control the voltage difference between the third gamma voltage GM3 and the fourth gamma voltage GM4 within a preset range. Figure 4 The middle gamma circuit 13 has the same configuration, ie, includes a plurality of resistors R connected in series, for dividing the power supply voltage AVDD and outputting a first gamma voltage GM1 , a second gamma voltage GM2 , a third gamma voltage GM3 and a fourth gamma voltage GM4 .

[0047] See also Figure 7 , Figure 7 for Figure 6 Circuit block diagram of the medium voltage regulation module.

[0048] Such as Figure 7As shown, the voltage adjustment module 132 includes a first adjustment unit 132a, a second adjustment unit 132b, a third adjustment unit 132c and a fourth adjustment unit 132d. The first adjustment unit 132a is electrically connected to the first gamma voltage output terminal, configured to receive the first gamma voltage GM1 and transmit the first gamma voltage GM1 to the data driving circuit 14 after adjustment. The second adjustment unit 132b is electrically connected to the second gamma voltage output terminal, configured to receive the second gamma voltage GM2 and transmit the second gamma voltage GM2 to the data driving circuit 14 after adjustment. The third adjustment unit 132c is electrically connected to the third gamma voltage output terminal, configured to receive the third gamma voltage GM3 and transmit the third gamma voltage GM3 to the data driving circuit 14 after adjustment. The fourth adjustment unit 132d is electrically connected to the fourth gamma voltage output terminal, configured to receive the fourth gamma voltage GM4 and transmit the fourth gamma voltage GM4 to the data driving circuit 14 after adjustment.

[0049] Specifically, the first adjustment unit 132a includes a first resistor R1 and a first capacitor C1. The first end of the first resistor R1 is electrically connected to the first gamma voltage output terminal, and the first end of the first resistor R1 is electrically connected to the data driving circuit 14. The first end of the first capacitor C1 is electrically connected to the second end of the first resistor R1, and the second end of the first capacitor C1 is electrically connected to the ground terminal GND. The second adjustment unit 132b includes a second resistor R2 and a second capacitor C2. The first end of the second resistor R2 is electrically connected to the second gamma voltage output terminal, and the second end of the second resistor R2 is electrically connected to the data driving circuit 14. The first end of the second capacitor C2 is electrically connected to the second end of the second resistor R2, and the second end of the second capacitor C2 is electrically connected to the ground terminal GND. The first resistor R1 is greater than the second resistor R2, and the first capacitor C1 is greater than or equal to the second capacitor C2. In a preferred embodiment, the resistance value of the second resistor R2 is equal to half of the first resistor R1, and the capacitance value of the second capacitor C2 is equal to the capacitance value of the first capacitor C1.

[0050] The third adjustment unit 132c includes a third resistor R3 and a third capacitor C3. The first end of the third resistor R3 is electrically connected to the third gamma voltage output terminal, and the second end of the third resistor R3 is electrically connected to the data driving circuit 14. The first end of the third capacitor C3 is electrically connected to the second end of the third resistor R3, and the second end of the third capacitor C3 is electrically connected to the ground terminal GND. The fourth adjustment unit 132d includes a fourth resistor R4 and a fourth capacitor C4. The first end of the fourth resistor R4 is electrically connected to the fourth gamma voltage output terminal, and the second end of the fourth resistor R4 is electrically connected to the data driving circuit 14. The first end of the fourth capacitor C4 is electrically connected to the second end of the fourth resistor R4, and the second end of the fourth capacitor C4 is electrically connected to the ground terminal GND. The third resistor R3 is equal to the fourth resistor R4, and the third capacitor C3 is equal to the fourth capacitor C4.

[0051] When the voltage AVDD drops, the first gamma voltage GM1 drops and the difference between the second gamma voltage GM2 is large, which causes the display panel to have a horizontal crosstalk. The embodiment controls the resistance value of the first resistor R1 to be greater than the resistance value of the second resistor R2, and controls the capacitance value of the first capacitor C1 to be greater than the capacitance value of the second capacitor C2, so that when the voltage AVDD drops, the difference between the first gamma voltage GM1 and the second gamma voltage GM2 is within a preset range, thereby effectively eliminating the horizontal crosstalk problem of the display panel.

[0052] Please refer to Figure 8 , Figure 8 The equivalent circuit schematic diagram of the second adjusting unit provided by the third embodiment of the present application is shown in FIG. 6. Figure 7

[0053] As shown in FIG. 5, the voltage adjusting module 132 further includes a detection unit 132e electrically connected to the second adjusting unit 132b. The detection unit 132e is configured to detect the drop degree of the voltage AVDD. When the drop value of the voltage AVDD is less than or equal to a preset threshold, the detection unit 132e outputs a first control signal to the second adjusting unit 132b to control the second adjusting unit 132b to adjust to a first preset resistance-capacitance. When the drop value of the voltage AVDD is greater than the preset threshold, the detection unit 132e outputs a second control signal to the second adjusting unit 132b to control the second adjusting unit 132b to adjust to a second preset resistance-capacitance. Figure 8 The first adjusting control component b1 and the second adjusting control component b2 of the second adjusting unit 132b. When the detection unit 132e outputs the first control signal, the first adjusting control component b1 receives the second gamma voltage GM2 and transmits the second gamma voltage GM2 to the data driving circuit 14 after adjustment. When the detection unit 132e outputs the second control signal, the second adjusting control component b2 receives the second gamma voltage GM2 and transmits the second gamma voltage GM2 to the data driving circuit 14 after adjustment.

[0054]

[0055] ​​Specifically, the first adjustment control component b1 includes a first switch tube Q1, a fifth resistor R5, and a fifth capacitor C5. The control end of the first switch tube Q1 is electrically connected to the detection unit 132e. The first end of the first switch tube Q1 is electrically connected to the second gamma voltage output end. The second end of the first switch tube Q1 is electrically connected to the first end of the fifth resistor R5. The second end of the fifth resistor R5 is electrically connected to the data driving circuit 14. The first end of the fifth capacitor C5 is electrically connected to the second end of the fifth resistor R5. The second end of the fifth capacitor C5 is electrically connected to the ground end GND. The first switch tube Q1 is turned on according to the first control signal, so as to receive the second gamma voltage GM2 from the second gamma voltage output end and transmit the second gamma voltage GM2 to the data driving circuit 14 through the fifth resistor R5 and the fifth capacitor C5. The fifth resistor R5 and the fifth capacitor C5 constitute a delay circuit, which is used to reduce the degree of voltage drop of the second gamma voltage GM2 caused by the load of the power supply voltage AVDD. The fifth resistor R5 is smaller than the first resistor R1, and the fifth capacitor C5 is smaller than or equal to the first capacitor C1.

[0056] The second adjustment control component b2 includes a second switch tube Q2, a sixth resistor R6, and a sixth capacitor C6. The first end of the second switch tube Q2 is electrically connected to the second gamma voltage output end. The second end of the second switch tube Q2 is electrically connected to the first end of the sixth resistor R6. The second end of the sixth resistor R6 is electrically connected to the data driving circuit 14. The first end of the sixth capacitor C6 is electrically connected to the second end of the sixth resistor R6. The second end of the sixth capacitor C6 is electrically connected to the ground end GND. The second switch tube Q2 is turned on according to the second control signal, so as to receive the second gamma voltage GM2 from the second gamma voltage output end and transmit the second gamma voltage GM2 to the data driving circuit 14 through the sixth resistor R6 and the sixth capacitor C6. The sixth resistor R6 and the sixth capacitor C6 constitute a delay circuit, which is used to reduce the degree of voltage drop of the second gamma voltage GM2 caused by the load of the power supply voltage AVDD.

[0057] The resistance value of the sixth resistor R6 is less than the resistance value of the fifth resistor R5, and the capacitance value of the sixth capacitor C6 is less than or equal to the capacitance value of the fifth capacitor C5. That is, when the voltage drop of the power supply voltage AVDD is less than or equal to the preset threshold value, a voltage drop difference between the first gamma voltage GM1 and the second gamma voltage GM2 occurs, that is, the voltage drop degree of the first gamma voltage GM1 is greater than the voltage drop degree of the second gamma voltage GM2. At this time, the second gamma voltage GM2 is adjusted by the fifth resistor R5 and the fifth capacitor C5. The fifth resistor R5 is controlled to be less than the first resistor R1, and the fifth capacitor C5 is controlled to be less than the first capacitor C1, so that the voltage drop difference between the first gamma voltage GM1 and the second gamma voltage GM2 is within the preset range. When the voltage drop of the power supply voltage AVDD is greater than the preset threshold value, the voltage drop difference between the first gamma voltage GM1 and the second gamma voltage GM2 is further increased, that is, the voltage drop of the first gamma voltage GM1 is further increased. At this time, the second gamma voltage GM2 is adjusted by the sixth resistor R6 and the sixth capacitor C6. The sixth resistor R6 is controlled to be less than the fifth resistor R5, and the sixth capacitor C6 is controlled to be less than the fifth capacitor C5. The voltage drop of the second gamma voltage GM2 is controlled to be increased while the voltage drop of the first gamma voltage GM1 is controlled to be reduced, so that the voltage drop difference between the first gamma voltage GM1 and the second gamma voltage GM2 is within the preset range. Thus, the crosstalk phenomenon caused by the voltage drop of the power supply voltage AVDD is eliminated, and the display effect is effectively improved.

[0058] Please refer to Figure 9 , Figure 9 for Figure 8 a schematic diagram of middle gamma voltage adjustment.

[0059] As shown in Figure 9 , in the first time period t1, when the data signal Data is from the 64th gray scale to the 255th gray scale, the power supply voltage AVDD is dropped due to voltage pumping. In the second time period t2, the power supply voltage AVDD gradually recovers to the initial voltage, and the first gamma voltage GM1 and the second gamma voltage GM2 also recover to the preset voltage.

[0060] In the first period t1, the first gamma voltage GM1 and the second gamma voltage GM2 also have different degrees of voltage drop due to the change of the power supply voltage AVDD. At this time, the detection unit 132e detects the voltage value of the power supply voltage AVDD drop, and when the voltage value of the power supply voltage AVDD drop is less than or equal to a preset threshold, the detection unit 132e outputs a first control signal to the second adjusting unit 132b. When the voltage of the power supply voltage AVDD drop is detected to be greater than the preset threshold, the detection unit 132e outputs a second control signal to the second adjusting unit 132b. The second adjusting unit 132b controls the first switch tube Q1 to be turned on according to the first control signal, or controls the second switch tube Q2 to be turned on according to the second control signal, so as to control the voltage difference between the second gamma voltage GM2 and the first gamma voltage GM1 to be within a preset range, so that the first gamma voltage VH1 and the second gamma voltage GM2 are symmetrical about the center reference voltage GM0. When the voltage difference between the second gamma voltage GM2 and the first gamma voltage GM1 is within the preset range, the display panel 10 will not have a horizontal crosstalk phenomenon due to data voltage draw, that is, the horizontal crosstalk phenomenon caused by data voltage draw is eliminated, and the image display effect is improved.

[0061] It should be understood that the application of the present application is not limited to the above examples, and those skilled in the art can make improvements or changes according to the above description, and all these improvements and changes shall belong to the protection scope of the appended claims of the present application.

Claims

1. A gamma circuit, characterized in that: comprising a voltage output module, the voltage output module being configured to output a first gamma voltage, a second gamma voltage, a third gamma voltage, and a fourth gamma voltage according to a received power voltage, the first gamma voltage, the second gamma voltage, the third gamma voltage, and the fourth gamma voltage being used as reference voltages to adjust a grayscale value of a data signal, the data signal being used to control a pixel unit in a display area to display an image; The gamma circuit also includes a voltage adjustment module, which is electrically connected to the voltage output module. The voltage adjustment module is used to adjust the voltage difference between the first gamma voltage and the second gamma voltage within a preset range, and adjust the voltage difference between the third gamma voltage and the fourth gamma voltage within a preset range.

2. The gamma circuit according to claim 1, wherein The first gamma voltage and the third gamma voltage are positive polarity reference voltages, used to adjust the grayscale value of the data signal with a positive polarity, wherein the first gamma voltage is greater than the third gamma voltage; the second gamma voltage and the fourth gamma voltage are negative polarity reference voltages, used to adjust the grayscale value of the data signal with a negative polarity, wherein the second gamma voltage is less than the fourth gamma voltage, the first gamma voltage and the second gamma voltage are symmetrical about a center reference voltage, and the third gamma voltage and the fourth gamma voltage are symmetrical about the center reference voltage.

3. The gamma circuit according to claim 2, wherein: The voltage adjustment module includes a first adjustment unit, a second adjustment unit, a third adjustment unit and a fourth adjustment unit, wherein the first adjustment unit is electrically connected to the first gamma voltage output terminal, and is used to receive the first gamma voltage and adjust the first gamma voltage before transmitting it to the data driving circuit; The second adjustment unit is electrically connected to the second gamma voltage output terminal, and is used for receiving the second gamma voltage and adjusting the second gamma voltage before transmitting it to the data driving circuit; The third adjustment unit is electrically connected to the third gamma voltage output terminal, and is used for receiving the third gamma voltage and adjusting the third gamma voltage before transmitting it to the data driving circuit; The fourth adjustment unit is electrically connected to the fourth gamma voltage output terminal, and is used to receive the fourth gamma voltage and adjust the fourth gamma voltage before transmitting it to the data driving circuit. The data driving circuit is used to output the data signal based on the first gamma voltage, the second gamma voltage, the third gamma voltage and the fourth gamma voltage as reference voltages.

4. The gamma circuit according to claim 3, wherein: The first adjustment unit includes a first resistor and a first capacitor, wherein a first end of the first resistor is electrically connected to the first gamma voltage output end, a second end of the first resistor is electrically connected to the data driving circuit, a first end of the first capacitor is electrically connected to the second end of the first resistor, and a second end of the first capacitor is electrically connected to the ground end; The second adjustment unit includes a second resistor and a second capacitor, wherein a first end of the second resistor is electrically connected to the second gamma voltage output terminal, a second end of the second resistor is electrically connected to the data driving circuit, a first end of the second capacitor is electrically connected to the second end of the second resistor, and a second end of the second capacitor is electrically connected to the ground terminal; The resistance value of the first resistor is greater than the resistance value of the second resistor, and the capacitance value of the first capacitor is greater than or equal to the capacitance value of the second capacitor.

5. The gamma circuit according to claim 3, wherein: The third adjustment unit includes a third resistor and a third capacitor, wherein a first end of the third resistor is electrically connected to the third gamma voltage output terminal, a second end of the third resistor is electrically connected to the data driving circuit, a first end of the third capacitor is electrically connected to the second end of the third resistor, and a second end of the third capacitor is electrically connected to the ground terminal; The fourth adjustment unit includes a fourth resistor and a fourth capacitor, wherein a first end of the fourth resistor is electrically connected to the fourth gamma voltage output terminal, a second end of the fourth resistor is electrically connected to the data driving circuit, a first end of the fourth capacitor is electrically connected to the second end of the fourth resistor, and a second end of the fourth capacitor is electrically connected to the ground terminal; The resistance value of the third resistor is equal to the resistance value of the fourth resistor, and the capacitance value of the third capacitor is equal to the capacitance value of the fourth capacitor.

6. The gamma circuit according to claim 3, wherein: The voltage adjustment module also includes a detection unit, which is electrically connected to the second adjustment unit. When the detection unit detects that the power supply voltage drop is less than or equal to a preset threshold, the detection unit outputs a first control signal to the second adjustment unit to control the second adjustment unit to adjust to a first preset resistance and capacitance. When the detection unit detects that the power supply voltage drops to greater than the preset threshold, the detection unit outputs a second control signal to the second adjustment unit to control the second adjustment unit to adjust to a second preset resistance and capacitance.

7. The gamma circuit according to claim 6, wherein: The second adjustment unit includes a first adjustment control component and a second adjustment control component. When the detection unit outputs the first control signal, the first adjustment component receives the second gamma voltage and adjusts the second gamma voltage before transmitting it to the data driving circuit. When the detection unit outputs the second control signal, the second adjustment component receives the second gamma voltage and adjusts the second gamma voltage before transmitting it to the data driving circuit.

8. The gamma circuit according to claim 7, wherein: The first adjustment component includes a first switching tube, a fifth resistor and a fifth capacitor, wherein the control end of the first switching tube is electrically connected to the detection unit, the first end of the first switching tube is electrically connected to the second gamma voltage output end, the second end of the first switching tube is electrically connected to the first end of the fifth resistor, the second end of the fifth resistor is electrically connected to the data driving circuit, the first end of the fifth capacitor is electrically connected to the second end of the fifth resistor, and the second end of the fifth capacitor is electrically connected to the ground end, wherein the resistance value of the fifth resistor is less than or equal to the resistance value of the first resistor, and the capacitance value of the fifth capacitor is less than or equal to the capacitance value of the first capacitor.

9. The gamma circuit according to claim 7, wherein: The second adjustment component includes a second switch tube, a sixth resistor and a sixth capacitor, wherein the control end of the second switch tube is electrically connected to the detection unit, the first end of the second switch tube is electrically connected to the second gamma voltage output end, the second end of the second switch tube is electrically connected to the first end of the sixth resistor, the second end of the sixth resistor is electrically connected to the data driving circuit, the first end of the sixth capacitor is electrically connected to the second end of the sixth resistor, and the second end of the sixth capacitor is electrically connected to the ground end, wherein the resistance value of the sixth resistor is less than the resistance value of the fifth resistor, and the capacitance value of the sixth capacitor is less than or equal to the capacitance value of the fifth capacitor.

10. A display panel, characterized in that: It includes a gamma circuit as described in any one of claims 1 to 9, a data driving circuit and a plurality of pixel units, wherein the data driving circuit is used to output a plurality of data signals of different gray levels according to the first gamma voltage, the second gamma voltage, the third gamma voltage and the fourth gamma voltage output by the gamma circuit, and transmit the data signals to the pixel units to drive the pixel units to display images.

Images