Display device

Abstract

A display device, capable of simplifying a power supply circuit for a backlight module (200), thereby improving the power supply efficiency of the display device. The display device comprises: a display panel (100); a backlight module (200), located on a light incident side of the display panel (100) and comprising first light-emitting element groups (210) and second light-emitting element groups (220), wherein power supply voltages of the first light-emitting element groups (210) and the second light-emitting element groups (220) are not equal; and a backlight driving circuit (300), comprising a transformer group, wherein the transformer group comprises a primary winding (310), a first secondary winding (321), and a second secondary winding (322), a positive output end of the first secondary winding (321) is electrically connected to the first light-emitting element groups (210), and a positive output end of the second secondary winding (322) is electrically connected to the second light-emitting element groups (220). The backlight driving circuit (300) further comprises at least one voltage conversion circuit (330). The voltage conversion circuit (330) and the second secondary winding (322) are connected in series between a ground end and the second light-emitting element groups (220). The voltage conversion circuit (330) is used for performing voltage conversion on an input voltage.

Description

Display device

[0001] Cross-references to related applications

[0002] This application claims priority to Chinese applications filed on January 24, 2025, application number 202510123459.9 and 202520174137.2, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of display technology, and more particularly to a display device. Background Technology

[0004] With the advancement and development of display technology, the requirements for power supply efficiency in display devices have increased. Since different colored light-emitting elements within the backlight module require different power supply voltages, it is necessary to provide separate power supplies for each color of light-emitting element.

[0005] Current display devices achieve independent power supply for different color light-emitting elements mainly by setting up multiple power supply circuits that can output different power supply voltages, or by connecting a voltage converter between the output terminal of a power supply voltage and the light-emitting element to adjust the input voltage of different light-emitting elements.

[0006] However, setting up multiple power supply circuits with different outputs increases the complexity of the power supply architecture of the backlight module, and the introduction of voltage converters inevitably leads to power loss during voltage conversion, affecting the power supply efficiency of the display device and increasing the manufacturing and operating costs of the display device. Summary of the Invention

[0007] Some embodiments of this application provide a display device, which may include: a display panel, including a light-emitting side and a light-receiving side; a backlight module located on the light-receiving side of the display panel, the backlight module including at least a first light-emitting element group and a second light-emitting element group, wherein the first light-emitting element group includes a first light-emitting element, the second light-emitting element group includes a second light-emitting element, and the supply voltage of the first light-emitting element group is not equal to the supply voltage of the second light-emitting element group; a backlight driving circuit, the backlight driving circuit including: a transformer group, including a primary winding and at least two secondary windings, the at least two secondary windings including a first secondary winding and a second secondary winding, the positive output terminal of the first secondary winding being electrically connected to the first light-emitting element group, and the positive output terminal of the second secondary winding being electrically connected to the second light-emitting element group; at least one voltage conversion circuit, the voltage conversion circuit and the second secondary winding being connected in series between a ground terminal and the second light-emitting element group, the voltage conversion circuit being used to perform voltage conversion on the input voltage; wherein the first secondary winding is used to provide the supply voltage of the first light-emitting element group, and the second secondary winding and the voltage conversion circuit connected in series are used to jointly provide the supply voltage of the second light-emitting element group. Attached Figure Description

[0008] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0009] Figure 1 is a schematic structural diagram of a display device according to an embodiment of this application;

[0010] Figure 2 is a schematic cross-sectional view of a display device according to an embodiment of this application;

[0011] Figure 3 is a schematic structural diagram of another display device in an embodiment of this application;

[0012] Figure 4 is a schematic structural diagram of another display device in an embodiment of this application;

[0013] Figure 5 is a schematic structural diagram of another display device according to an embodiment of this application;

[0014] Figure 6 is a schematic structural diagram of a display device according to an embodiment of this application;

[0015] Figure 7 is a schematic structural diagram of a transformer group of a display device according to an embodiment of this application;

[0016] Figure 8 is a schematic structural diagram of a backlight driving circuit of a display device according to an embodiment of this application;

[0017] Figure 9 is a schematic structural diagram of another display device in an embodiment of this application;

[0018] Figure 10 is a schematic structural diagram of another display device in an embodiment of this application;

[0019] Figure 11 is a schematic structural diagram of another display device according to an embodiment of this application;

[0020] Figure 12 is a schematic overall architecture diagram of a display device according to an embodiment of this application. Detailed Implementation

[0021] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0022] 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 this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0023] It should be understood that when an element or layer is referred to as "on," "adjacent to," "electrically connected to," or "coupled to" other elements or layers, it may be directly on, adjacent to, electrically connected to, or coupled to other elements or layers, or there may be intervening elements or layers. Conversely, when an element is referred to as "directly on," "directly adjacent to," "directly electrically connected to," or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc., may be used to describe various elements, parts, regions, layers, doping types, and / or portions, these elements, parts, regions, layers, doping types, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, part, region, layer, doping type, or portion from another element, part, region, layer, doping type, or portion. Therefore, without departing from the teachings of this invention, the first element, component, region, layer, doping type, or portion discussed below may be represented as a second element, component, region, layer, or portion; for example, the first doping type may be referred to as the second doping type, and similarly, the second doping type may be referred to as the first doping type; the first doping type and the second doping type are different doping types, for example, the first doping type may be P-type and the second doping type may be N-type, or the first doping type may be N-type and the second doping type may be P-type.

[0024] Spatial relation terms such as “below,” “under,” “below,” “under,” “above,” “above,” etc., are used herein to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms also include different orientations of the device in use and operation. For example, if the device in the figure is flipped, the element or feature described as “below,” “under,” or “below” will be oriented “above” the other element or feature. Therefore, the exemplary terms “below” and “under” can include both above and below orientations. Furthermore, the device may also include other orientations (e.g., rotated 90 degrees or other orientations), and the spatial descriptive terms used herein will be interpreted accordingly.

[0025] When used herein, the singular forms of "a," "an," and " / the" may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms "comprising / including" or "having," etc., specify the presence of the stated features, integrals, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, integrals, steps, operations, components, parts, or combinations thereof. Meanwhile, in this specification, the term "and / or" includes any and all combinations of the associated listed items. With the advancement and development of display technology, the requirements for the power supply efficiency of display devices have increased. Since different colored light-emitting elements within the backlight module require different supply voltages, it is necessary to design multiple power supply circuits to individually power the different colored light-emitting elements.

[0026] It should be noted that in display devices of related technologies, multiple LLC half-bridge resonant circuits are usually set as the power supply circuits of the backlight module. By controlling the switching frequency of the switching transistors in the LLC half-bridge resonant circuits, the output terminal of each LLC half-bridge resonant circuit can output different power supply voltages to meet the power requirements of different light-emitting elements.

[0027] Current LLC architectures typically include two metal-oxide-semiconductor field-effect transistors (MOSFETs), a controller, and a transformer, outputting three different voltages through three LLCs. To accommodate consistent lamp voltage ranges and reduce line voltage losses, voltage feedback is often required in practical applications across the three LLCs. This involves adjusting the LLC output voltage based on the feedback signal to match the existing voltage requirements. This requires three existing LLC chips and corresponding driver circuitry. However, a three-LLC approach undoubtedly increases the power supply area and incurs higher costs.

[0028] As can be seen, the aforementioned power supply circuit architecture is highly complex, uses numerous electronic components, and occupies a large area of ​​the power board, leading to increased manufacturing costs and greater difficulty in control. Taking a total input power of 300W as an example, under ideal operating conditions of the LLC half-bridge resonant circuit, each LLC outputs 100W. However, in actual operation, certain power losses occur, resulting in a total output power of only 285W for the LLC half-bridge resonant circuit, a power loss of 15W, and a power efficiency of 95%.

[0029] In related technologies, some display devices also have multiple voltage converters at the output of an LLC half-bridge resonant circuit. These voltage converters convert the voltage output by the LLC half-bridge resonant circuit so that the converted voltage can meet the power requirements of different light-emitting elements.

[0030] However, the power efficiency of the LLC half-bridge resonant circuit in the above power supply circuit is usually around 95% during the power output process, and the power efficiency of the voltage converter in the above power supply circuit is usually around 95% during the power output process. Therefore, during the power transfer process, the power architecture of one LLC half-bridge resonant circuit plus three voltage converters will cause the power output of the LLC half-bridge resonant circuit to be lost, which will further reduce the power efficiency to 90.25%. Taking a total input power of 300W as an example, under ideal operating conditions, each output terminal is set to output 100W. However, in actual operation, a certain amount of power loss will occur. The actual output power of each output terminal is 100 × 95% × 95% = 90.25W, so the actual output power of each output terminal is 90.25W. The actual total output power of the power supply architecture is 90.25 × 3 = 270.75W, so the actual total output power of the power supply architecture is 270.75W, resulting in a power loss of 29.25W. The power efficiency is 270.75 / 300 = 90.25%, so the actual efficiency of the power supply architecture is 90.25%.

[0031] In view of this, the present application provides a display device that can simplify the power supply circuit of the backlight module, reduce energy loss during the light emission process of the display device, improve the power supply efficiency of the display device, and save the manufacturing and usage costs of the display device.

[0032] As shown in Figures 1 and 2, the display device according to an embodiment of this application may include a display panel 100. The display panel 100 includes a light-emitting side and a light-receiving side.

[0033] In some embodiments, the display device includes a backlight module 200; wherein the backlight module 200 is located on the light-incident side of the display panel 100, and the backlight module 200 includes at least a first light-emitting element group 210 and a second light-emitting element group 220, wherein the first light-emitting element group 210 includes a first light-emitting element, the second light-emitting element group 220 includes a second light-emitting element, and the power supply voltage of the first light-emitting element group 210 is not equal to the power supply voltage of the second light-emitting element group 220.

[0034] In some embodiments, the wavelengths of the light emitted by the first light-emitting element group 210 and the second light-emitting element group 220 may be different. For example, the colors of the light emitted by the first light-emitting element group 210 and the second light-emitting element group 220 may be different. The colors of the light emitted by the first light-emitting element group 210 and the second light-emitting element group 220 may be any two of red, green, and blue.

[0035] In some embodiments, the display device includes a backlight driving circuit 300; wherein the backlight driving circuit 300 includes: a transformer group including a primary winding 310 and at least two secondary windings 320; the secondary windings 320 include a first secondary winding 321 and a second secondary winding 322;

[0036] The positive output terminal of the first secondary winding 321 is electrically connected to the first light-emitting element group 210, and the positive output terminal of the second secondary winding 322 is electrically connected to the second light-emitting element group 220; at least one voltage conversion circuit 330 is connected in series between the voltage conversion circuit 330 and the second secondary winding 322 and the ground terminal and the second light-emitting element group 220, and the voltage conversion circuit 330 is used to convert the input voltage.

[0037] In some embodiments, the backlight module 200 and the backlight driving circuit 300 can be disposed on the same layer on the circuit board.

[0038] In some embodiments, the positive output terminal of the first secondary winding 321 is used to output a DC voltage with a first voltage value, which is equal to the supply voltage of the first light-emitting element group 210, and the negative output terminal of the first secondary winding 321 is used to ground.

[0039] It should be noted that the power supply voltage of the first light-emitting element group 210 is a floating voltage. The voltage output from the positive output terminal of the first secondary winding 321 is adjusted according to the floating voltage required by the first light-emitting element group 210, so that the voltage output from the positive output terminal of the first secondary winding 321 can be directly used to power the first light-emitting element group 210. The connection method of the primary winding 310 of the transformer group can be the same as the connection method of the primary coil of the transformer group in the LLC half-bridge resonant circuit.

[0040] In some embodiments, the first light-emitting element group 210 can be the light-emitting element group in the backlight module 200 that requires the lowest supply voltage. Using the supply voltage required by the first light-emitting element group 210 as the reference voltage for adjusting the primary winding 310 can improve the accuracy of the voltage value input to the input terminal of the first light-emitting element group 210, improve the display effect of the first light-emitting element group 210, and prevent the first light-emitting element group 210 from burning out due to excessive voltage. Furthermore, the voltage output of the voltage conversion circuit 330 can be adjusted according to the voltage value output from the positive output terminal of the first secondary winding 321. Thus, different input voltages can be provided to the first light-emitting element group 210 and at least one second light-emitting element group 220 with different required supply voltages. At the same time, feedback adjustment can be formed on the voltage conversion circuit 330 based on the voltage output from the positive output terminal of the first secondary winding 321, thereby enabling stepped power supply to the first light-emitting element group 210 and at least one second light-emitting element 220 through the backlight driving circuit 300.

[0041] It should be noted that the second secondary winding 322 is connected in series with the voltage conversion circuit 330 to jointly power the second light-emitting element group 220. This reduces the adjustment range of the voltage conversion circuit 330, improves the accuracy of voltage regulation, and further enhances the display effect of the backlight module. Simultaneously, the voltage conversion circuit 330 can be formed using low-voltage electronic components, reducing the cost of the backlight driving circuit 300 and improving its reliability. For example, when the supply voltage of the second light-emitting element group 220 is 10V, the voltage output directly from the positive output terminal of the second secondary winding 322 to the second light-emitting element group 220 is 5V, and the voltage conversion circuit 330 also directly outputs 5V to the second light-emitting element group 220. Therefore, compared to display devices that use only the voltage conversion circuit 330 for voltage regulation, the adjustment range of the voltage conversion circuit 330 in the display device provided in this application embodiment is relatively small.

[0042] In some embodiments, the positive output terminal of the first secondary winding 321 can be directly electrically connected to the input terminal of the first light-emitting element group 210, or a rectifier can be connected between the positive output terminal of the first secondary winding 321 and the input terminal of the first light-emitting element group 210. The positive output terminal of the second secondary winding 322 can be directly electrically connected to the input terminal of the second light-emitting element group 220, or a rectifier can be connected between the positive output terminal of the second secondary winding 322 and the input terminal of the second light-emitting element group 220.

[0043] In some embodiments, the voltage conversion circuit 330 may include a DC-DC converter. The input terminal of the voltage conversion circuit 330 may be connected to an external power supply voltage to convert the DC power input from the external power supply into DC power with a target voltage value. Alternatively, the input terminal of the voltage conversion circuit 330 may be connected to the positive output terminal of the first secondary winding 321 to convert the voltage output from the first secondary winding 321 into DC power with a target voltage value. The output terminal of the voltage conversion circuit 330 is used to output DC power with a target voltage value, and the positive output terminal of the second secondary winding 322 is used to output DC power with a second voltage value. The sum of the target voltage and the second voltage is equal to the supply voltage of the second light-emitting element group 220.

[0044] In some embodiments, the backlight driving circuit 300 may further include a controller, the input terminal of which is electrically connected to the positive output terminal of the first secondary winding 321, and the output terminal of which is electrically connected to the input terminal of the voltage conversion circuit 330. The controller is used to determine the fluctuation amplitude of the voltage output from the positive output terminal of the second secondary winding 322 based on the fluctuation of the voltage signal at the positive output terminal of the first secondary winding 321, thereby determining the required output voltage for the voltage conversion circuit 330. Furthermore, the controller generates a control signal for the voltage conversion circuit 330 based on the required output voltage, so that the voltage conversion circuit 330 can adjust the magnitude of the output voltage according to the control signal. This ensures that the voltage output from the positive output terminal of the second secondary winding 322 and the voltage output from the voltage conversion circuit 330 together meet the power supply voltage required by the second light-emitting element group 220. This allows for high-frequency adjustment of the voltage conversion of the voltage conversion circuit 330, further improving the stability and accuracy of the input voltage at the input terminal of the second light-emitting element group 220.

[0045] The first secondary winding 321 is used to provide the power supply voltage for the first light-emitting element group 210, and the second secondary winding 322 and the voltage conversion circuit 330 connected in phase are used to jointly provide the power supply voltage for the second light-emitting element group 220.

[0046] In some embodiments, when the transformer group includes a first secondary winding 321 and two second secondary windings 322, and the backlight driving circuit 300 includes two voltage conversion circuits 330, it is assumed that under ideal conditions, the total output power of the secondary windings in the backlight driving circuit 300 is 300W. Under ideal conditions, the first secondary winding 321 outputs 100W of power to the first light-emitting element group 210. Due to energy loss, 100 × 95% = 95, the actual output power of the first secondary winding 321 and the second secondary winding 322 is 95W. Therefore, the actual input power at the input terminal of the first light-emitting element group 210 is only 95W.

[0047] In some embodiments, the first secondary winding 321 is responsible for the power adjustment required by the second light-emitting element group 220. For example, ideally, the first secondary winding 321 also needs to handle the 25W power adjustment required by each of the two second light-emitting element groups 220. Therefore, 50W of electrical energy needs to undergo two power losses through the transformer group and the voltage conversion circuit 330, 50 × 95% × 95% = 45.125W. So the actual power output by the two voltage conversion circuits 330 is 45.125W. At the same time, the electrical energy directly obtained from the input terminal of the second secondary winding 322 of the second light-emitting element group 220 undergoes one power loss through the transformer group, 75 × 95% = 71.25W. So the actual power output by the output terminals of the two second secondary windings 322 is 71.25W. Therefore, in the display device provided in this application embodiment, 71.25×2+95=282.625, the total power actually output by each output terminal of the backlight driving circuit 300 is 282.625W, and further, 282.625 / 300=94.2%, the power efficiency actually output by each output terminal of the backlight driving circuit 300 is 94.2%.

[0048] Compared to display devices in related technologies that use a three-channel LLC half-bridge resonant circuit as the power supply circuit for the backlight module, the power supply architecture of the display device provided in this application embodiment is simple, requires a smaller power board area, and reduces the manufacturing cost of the display device.

[0049] Compared to related technologies where a single LLC half-bridge resonant circuit is used to connect three voltage converters in series as the power supply circuit for the backlight module, the display device provided in this application allows the second secondary winding 322 to be relatively independent from the voltage conversion circuit 330. This reduces power loss in the backlight driving circuit 300 during power supply and lowers the cost of using the display device. Simultaneously, by adjusting the output voltage based on the actual voltage output from the first secondary winding 321, the voltage conversion circuit 330 can further improve voltage regulation efficiency and accuracy. This enhances the sensitivity of the backlight driving circuit 300, improves the luminous effect of different light-emitting element groups in the backlight module, and ultimately improves the display effect and quality of the display device.

[0050] The display device provided in this application embodiment, by setting a transformer group including a first secondary winding 321 and a second secondary winding 322, and electrically connecting the positive output terminal of the first secondary winding 321 to the input terminal of the first light-emitting element group 210, allows the first secondary winding 321 of the transformer group to directly supply power to the first light-emitting element group 210. Simultaneously, by connecting a voltage conversion circuit 330 to the negative output terminal of the second secondary winding 322 of the transformer group, the voltage conversion circuit 330 can use the voltage output from the positive output terminal of the first secondary winding 321 as the basis for feedback adjustment. Through voltage conversion, the voltage conversion circuit 330 can compensate for the voltage output from the second secondary winding 332, thereby meeting the power supply voltage requirements of the second light-emitting element group 220. This allows for the provision of different input voltages to the first light-emitting element group 210 and at least one second light-emitting element group 220, which require different supply voltages. Simultaneously, feedback regulation can be established for the voltage conversion circuit 330 based on the voltage output from the positive output terminal of the first secondary winding 321. Furthermore, the backlight driving circuit 300 can achieve stepped power supply to the first light-emitting element group 210 and at least one second light-emitting element 220. This simplifies the power supply circuit of the backlight module 200. Moreover, the voltage conversion circuit 330 is independent of the second secondary winding 322, reducing energy loss during conversion and lowering the manufacturing and operating costs of the display device. Using the voltage conversion circuit 330 also improves voltage regulation efficiency, further enhancing the sensitivity of the backlight driving circuit 300. Ultimately, this improves the luminous effect of different light-emitting element groups in the backlight module 200, thereby enhancing the display effect and quality of the display device.

[0051] Furthermore, in display devices of this technology, the reference input terminal of the voltage conversion circuit 330 is typically connected to the motherboard of the display device to obtain the 12V motherboard voltage as a reference voltage. However, the motherboard voltage of the display device is significantly affected by temperature, easily causing noticeable temperature drift, which leads to fluctuations in the voltage input to the reference input terminal of the voltage conversion circuit 330.

[0052] Display devices using related technologies typically lack a motherboard voltage feedback mechanism. Therefore, without obtaining real-time voltage feedback from the motherboard, the voltage conversion circuit 330 performs voltage conversion based on a fixed 12V voltage. This results in a voltage difference between the actual output voltage and the expected output voltage of the voltage conversion circuit 330, affecting the accuracy of power supply to the second light-emitting element group 220 and consequently impacting the display effect of the display device.

[0053] Based on this, in some embodiments, the voltage conversion circuit 330 of the display device further includes a voltage input terminal, which is connected to the positive output terminal of the first secondary winding 321. By electrically connecting the voltage input terminal of the voltage conversion circuit 330 to the positive output terminal of the first secondary winding 321, the voltage conversion circuit 330 can easily obtain real-time feedback from the positive output terminal of the first secondary winding 321, so as to adjust the voltage conversion mechanism according to the voltage change output from the positive output terminal of the first secondary winding 321. Furthermore, the voltage output by the voltage conversion circuit 330 can be matched with the voltage output from the positive output terminal of the second secondary winding 322, thereby accelerating the adjustment frequency of the voltage conversion circuit 330, further improving the stability and accuracy of the input voltage at the input terminal of the second light-emitting element group 220, and improving the accuracy of the output voltage of the backlight driving circuit 300, thereby improving the display effect and display quality of the display device.

[0054] As shown in Figure 1 above, the number of voltage conversion circuits 330 in the backlight driving circuit 300 is equal to the number of second secondary windings 322. The second secondary windings 322 correspond to the voltage conversion circuits 330, and the backlight module 200 includes at least two second light-emitting element groups 220 with different power supply voltages.

[0055] In some embodiments, the number of second light-emitting element groups 220 with different supply voltages is equal to the number of voltage conversion circuits 330 within the backlight driving circuit 300. Alternatively, the number of second light-emitting element groups 220 with different supply voltages is greater than the number of voltage conversion circuits 330 within the backlight driving circuit 300. The positive output terminal of each second secondary winding 322 is electrically connected to one second light-emitting element group 220, and the negative output terminal is electrically connected to the output terminal of one voltage conversion circuit 330.

[0056] In this way, the second secondary winding 322 can be set in correspondence with the voltage conversion circuit 330, which can further improve the adjustment accuracy of the input voltage of the second light-emitting element group 220 and improve the voltage regulation capability of the backlight driving circuit 300, thereby improving the sensitivity of the display device and improving the display effect and display quality.

[0057] In some embodiments, the supply voltage of the first light-emitting element group 210 is lower than the supply voltage of the second light-emitting element group 220.

[0058] It should be noted that the voltages at the positive output terminals of the first secondary winding 321 and the second secondary winding 322, which correspond to the same primary winding 310, will change synchronously.

[0059] The display device provided in this application embodiment, by using the light-emitting element group with the lowest supply voltage as the first light-emitting element group 210 directly electrically connected to the positive output terminal of the first secondary winding 321, can prevent the voltage input to the input terminal of the first light-emitting element group 210 from being too high, thereby improving the safety and reliability of the backlight driving circuit 300.

[0060] As shown in Figure 3, in some embodiments, a second secondary winding 322 and a voltage conversion circuit 330 are used together to provide the power supply voltage for at least two second light-emitting element groups 220.

[0061] In some embodiments, a second secondary winding 322 may be electrically connected to the input terminals of at least two second light-emitting element groups 220. As shown in FIG3, a second secondary winding 322 may include a positive output terminal, a voltage conversion circuit 330 may be connected in series with the negative output terminal of the second secondary winding 322, and the positive output terminal of the second secondary winding 322 may be electrically connected to the input terminals of at least two second light-emitting element groups 220.

[0062] In some embodiments, a second secondary winding 322 may include at least two positive output terminals, and the voltage conversion circuit 330 may include at least two positive output terminals. One output terminal of the voltage conversion circuit 330 is connected between a positive output terminal of the second secondary winding 322 and an input terminal of a second light-emitting element group 220. The number of positive output terminals of the second secondary winding 322 may be equal to the number of second light-emitting element groups 220, and the number of positive output terminals of the second secondary winding 322 may be equal to the number of positive output terminals of the voltage conversion circuit 330.

[0063] In some embodiments, at least two second light-emitting element groups 220 connected to the same second secondary winding 322 and the same voltage conversion circuit 330 require similar supply voltages.

[0064] The display device provided in this application embodiment supplies power to at least two second light-emitting element groups 220 through a second secondary winding 322 and a voltage conversion circuit 330. This allows multiple second light-emitting element groups 220 to share a second secondary winding 322 and a voltage conversion circuit 330, enabling coarse adjustment of the voltage input to the input terminal of the second light-emitting element group 220. This further simplifies the circuit architecture of the backlight driving circuit 300, reduces the complexity of the backlight driving circuit 300, reduces the control difficulty of the voltage conversion circuit 330, and improves the voltage regulation efficiency, thereby reducing the manufacturing cost and usage cost of the display device.

[0065] In some embodiments, as shown in Figures 4 and 5, a second secondary winding 322 and at least two voltage conversion circuits 330 are used to jointly provide power supply voltage for at least two second light-emitting element groups 220. The second secondary winding 322 may include at least two positive output terminals, and the number of positive output terminals of the second secondary winding 322 may be equal to the number of voltage conversion circuits 330.

[0066] The display device provided in this application embodiment supplies power to at least two second light-emitting element groups 220 through a second secondary winding 322 and at least two voltage conversion circuits 330. This allows multiple second light-emitting element groups 220 to share a single second secondary winding 322. The second secondary winding 322 coarsely adjusts the voltage input to the input terminals of the second light-emitting element groups 220, and the voltage conversion circuits 330 further compensate and correct the voltage input to the input terminals of the second light-emitting element groups 220. This improves the accuracy of the voltage input to the input terminals of the second light-emitting element groups 220, enhances the display effect and quality of the display device, saves the second secondary winding 322, simplifies the circuit architecture of the backlight driving circuit 300, reduces the complexity of the backlight driving circuit 300, reduces the control difficulty of the voltage conversion circuit 330, and improves voltage regulation efficiency, thereby reducing the manufacturing and usage costs of the display device.

[0067] As shown in Figure 6, the backlight driving circuit 300 includes a voltage conversion circuit 330, the transformer group includes at least two second secondary windings 322, and the backlight module 200 includes at least two second light-emitting element groups 220 with different power supply voltages.

[0068] In some embodiments, the colors of the light emitted by the second light-emitting element groups 220 with different supply voltages can be different. Specifically, the positive output terminal of one second secondary winding 322 is electrically connected to the second light-emitting element group 220 with a first supply voltage, and its negative output terminal is electrically connected to the output terminal of the voltage conversion circuit 330. The positive output terminal of the other second secondary winding 322 is electrically connected to another second light-emitting element group 220 with a second supply voltage, and its negative output terminal is electrically connected to the output terminal of the voltage conversion circuit 330.

[0069] In some embodiments, the positive output terminals of at least two second secondary windings 322 output different voltages. One second secondary winding 322's positive output terminal outputs a DC voltage equal to a first sub-voltage, the other second secondary winding 322's positive output terminal outputs a DC voltage equal to a second sub-voltage, and the output terminal of the voltage conversion circuit 330 outputs a DC voltage equal to a target voltage. The first supply voltage is equal to the sum of the first sub-voltage and the target voltage, and the second supply voltage is equal to the sum of the second sub-voltage and the target voltage.

[0070] The display device provided in this application embodiment, by setting a voltage conversion circuit 330 and at least two second secondary windings 322, allows multiple second light-emitting element groups 220 with different supply voltages to share a single voltage conversion circuit 330, thereby simplifying the circuit architecture of the backlight driving circuit 300. Furthermore, by adjusting the number of coil turns of the second secondary windings 322, different voltages can be output from the positive output terminals of different second secondary windings 322. This allows for adjustment of the voltage input to the input terminals of different second light-emitting element groups 220 under the compensation effect of the voltage conversion circuit 330. Individual power supply to second light-emitting element groups 220 with different supply voltages can be achieved, further improving the backlight driving circuit 300's control over the output voltage, increasing the accuracy of power supply to the light-emitting element groups, reducing energy loss during energy conversion, improving the energy transmission efficiency of the display device, enhancing the display effect and quality, and saving on the manufacturing and usage costs of the display device.

[0071] In some embodiments, the number of coil turns of the second secondary winding 322 of the second light-emitting element group 220 electrically connected to different supply voltages is not equal.

[0072] It should be noted that in the transformer group, the ratio of the number of turns of the primary winding 310 to the number of turns of the secondary winding 320 is related to the magnitude of the output voltage of the secondary winding 320.

[0073] The display device provided in this application embodiment, by setting the number of turns of the coil of the second secondary winding 322 of the second light-emitting element group 220, which is electrically connected to different power supply voltages, is not equal. This facilitates coarse adjustment of the voltage value input to the input terminal of the second light-emitting element group 220, reduces the adjustment range of the voltage conversion circuit 330, and avoids the voltage conversion circuit 330 from frequently performing large voltage adjustments, which would increase the risk of burnout. This improves the safety of the voltage conversion circuit 330, reduces the control difficulty of the voltage conversion circuit 330, and thus reduces the operating cost of the display device.

[0074] In some embodiments, at least two secondary windings 320 of the transformer bank have different numbers of turns.

[0075] In some embodiments, the number of turns of the first secondary winding 321 and the second secondary winding 322 of the transformer group may be different, and the number of turns of any two second secondary windings 322 of the transformer group may also be different.

[0076] In some embodiments, the number of turns of the first secondary winding 321 can be determined based on the number of turns of the primary winding 310 of the transformer group and the power supply voltage required by the first light-emitting element group 210.

[0077] The display device provided in this application embodiment, by setting the number of turns of at least two secondary windings 320 of the transformer group to be different, can easily make coarse adjustments to the voltage output at the positive output terminal of the secondary winding 320 by adjusting the ratio of the number of turns of the secondary winding 320 to the number of turns of the primary winding 310. This further reduces the adjustment difficulty of the backlight driving circuit 300 and lowers the cost of using the display device.

[0078] In some embodiments, the transformer bank includes at least two first secondary windings 321, wherein the positive output terminal of each first secondary winding 321 is electrically connected to the first light-emitting element group 210. For example, the transformer bank shown in FIG7 includes two first secondary windings 321, and the positive output terminal of each first secondary winding 321 is electrically connected to the first light-emitting element group 210.

[0079] In some embodiments, the voltages output from the positive output terminals of at least two first secondary windings 321 are equal to provide a power supply voltage to the first light-emitting element group 210.

[0080] In some embodiments, the currents output from the positive output terminals of at least two first secondary windings 321 are equal. It should be noted that the first secondary windings 321 of the transformer bank generate a large amount of heat when outputting a large current, which can easily cause the first light-emitting element group 210 to be in an overheated environment, affecting the light-emitting effect of the first light-emitting element group 210 and reducing the accuracy of the emitted light, thus affecting the light-emitting effect of the first light-emitting element group 210.

[0081] The display device provided in this application embodiment, by providing at least two first secondary windings 321 to power the same first light-emitting element group 210, can reduce the voltage or current on each first secondary winding 321, and further reduce the heat generated during power transmission. Simultaneously, it can increase the area occupied by the positive output terminal of the first secondary winding 321, increasing the heat dissipation space of the first secondary winding 321, further improving the heat dissipation effect of the backlight driving circuit 300, and preventing color shift in the light emitted from the first light-emitting element group 210 and the second light-emitting element group 220 in the backlight module 200 due to excessive temperature. This improves the control precision and control capability of the backlight driving circuit 300 over the light-emitting element group, and enhances the display effect and display quality of the display device.

[0082] As shown in Figure 7, the positive output terminals of each of the first secondary windings 321 are used to jointly provide the power supply current for the first light-emitting element group 210.

[0083] In some embodiments, the current output at the positive output terminal of each of the first secondary windings 321 can be equal.

[0084] The display device provided in this application embodiment provides current to the first light-emitting element group 210 through at least two first secondary side windings 321, which can reduce the current on each first secondary side winding 321 and further reduce the heat dissipated by the backlight driving circuit 300. Simultaneously, it can increase the area occupied by the positive output terminal of the first secondary side winding 321, increasing the heat dissipation space of the first secondary side winding 321, further improving the heat dissipation effect of the backlight driving circuit 300, and preventing color shift of the light emitted from the first light-emitting element group 210 and the second light-emitting element group 220 in the backlight module 200 due to excessive temperature. Therefore, it can improve the control precision and control capability of the backlight driving circuit 300 over the light-emitting element group, and improve the display effect and display quality of the display device.

[0085] In some embodiments, the transformer bank may include at least two primary windings 310 and at least two first secondary windings 321. Of the at least two primary windings 310, at least one primary winding 310 corresponds to at least one first secondary winding 321 and a portion of a second secondary winding 322, and the remaining primary windings 310 correspond to the remaining first secondary windings 321 (excluding the at least one first secondary winding 321) and the remaining portion of the second secondary windings 322.

[0086] For ease of understanding, please refer to Figure 8. The transformer group shown in Figure 8 includes two primary windings 310 and two first secondary windings 321. One primary winding 310 corresponds to one first secondary winding 321 and part of the second secondary winding 322, and the other primary winding 310 corresponds to another first secondary winding 321 and the remaining part of the second secondary winding 322.

[0087] In some embodiments, the voltage and current input to the primary winding 310 of different transformer banks may be different. The voltage output to the first secondary winding 321 of different transformer banks may be the same, but the current may be different. The number of turns in the first secondary winding 321 of different transformer banks may be different.

[0088] The display device provided in this application embodiment, by setting a transformer group including two primary windings 310 and two first secondary windings 321, can set the voltage and current input on the primary windings 310 corresponding to different second secondary windings 322, so that the output of the secondary windings 320 can be coarsely adjusted by adjusting the input of the primary windings 310. This can further reduce the control difficulty of the voltage conversion circuit 330, improve the voltage regulation efficiency, improve the accuracy of power supply to the light-emitting element group, reduce the power loss generated by energy conversion, improve the energy transmission efficiency of the display device, and improve the display effect and display quality of the display device.

[0089] As shown in Figure 9, in the case of a transformer group including two primary windings 310 and two first secondary windings 321, the display device provided in this application can share a part of the front-end control circuit by connecting at least two primary windings 310 in series. This can further simplify the circuit architecture of the backlight driving circuit 300, reduce the control difficulty of the backlight driving circuit 300, reduce the power loss generated by energy conversion, improve the energy transmission efficiency of the display device, and reduce the manufacturing cost of the display device.

[0090] As shown in Figure 9, in some embodiments, the positive output terminals of the second secondary windings 322 corresponding to different primary windings 310 are electrically connected to second light-emitting element groups 220 with different supply voltages. That is, among at least two primary windings 310, the supply voltage of the second light-emitting element group connected to the positive output terminal of at least one primary winding 310 corresponding to the second secondary winding 322 is different from that of the second light-emitting element groups connected to the positive output terminals of the remaining primary windings 310 corresponding to the second secondary windings 322.

[0091] This configuration further enhances the control capability of the primary winding 310 of the transformer group over the input voltage of the second light-emitting element group 220, narrows the adjustment range of the voltage conversion circuit 330, and thus reduces the control difficulty of the voltage conversion circuit 330. It can also improve the voltage regulation efficiency of the backlight drive circuit 300, reduce power loss during energy conversion, and consequently improve the energy transmission efficiency of the display device.

[0092] In some embodiments, the number of the first secondary windings 321 is positively correlated with the supply current of the first light-emitting element group 210. It should be noted that the larger the supply current of the first light-emitting element group 210, the higher the heat generated by current transmission.

[0093] The display device provided in this application embodiment, by setting the number of the first secondary side windings 321 to be positively correlated with the supply current of the first light-emitting element group 210, can increase the number of the first secondary side windings 321 when the supply current of the first light-emitting element group 210 is large, thereby improving the heat dissipation efficiency of the backlight driving circuit 300 and enhancing the reliability and stability of the display device. When the supply current of the first light-emitting element group 210 is small, increasing the number of the first secondary side windings 321 can further save on the manufacturing cost of the backlight driving circuit 300, simplify its circuit architecture, reduce the control difficulty of the backlight driving circuit 300, reduce energy loss during energy conversion, and improve the energy transmission efficiency of the display device.

[0094] As shown in Figure 10, in some embodiments, the display device further includes a first feedback unit 400. The input terminal of the first feedback unit 400 is used to acquire a first control signal from the first light-emitting element group 210. The output terminal of the first feedback unit 400 is electrically connected to the input terminal of the primary winding 310 of the transformer group. The first feedback unit 400 is used to provide a first feedback signal 801 according to the first control signal. The first feedback signal 801 is used to adjust the voltage of the primary winding 310 of the transformer group. The transmission path of the first feedback signal 801 can be referred to Figure 9.

[0095] In some embodiments, the first feedback signal 801 can be used to control the duty cycle of the S1 and S2 switching transistors, and further adjust the input voltage of the primary winding 310 of the transformer bank.

[0096] In some embodiments, the first feedback unit 400 may include a driver chip, which is electrically connected to the light-emitting element group in the backlight module 200 and is used to drive different light-emitting element groups to emit light, which can be determined by the driver chip.

[0097] The display device provided in this application embodiment obtains a first control signal from the control terminal of the first light-emitting element group 210 through the input terminal of the first feedback unit 400. Based on the first control signal, the current light-emitting state of the first light-emitting element group 210 can be determined. Furthermore, the difference between the current light-emitting state and the target light-emitting state of the first light-emitting element group 210 can be determined, and a first feedback signal 801 is generated based on the difference. This allows the secondary winding 320 of the transformer group to output a corresponding voltage based on the first feedback signal 801. This enables the adjustment of the voltage input to the input terminal of the first light-emitting element group 210, improving the accuracy of the light emission of the first light-emitting element group 210 and enhancing its light-emitting effect. Simultaneously, it allows for coarse adjustment of the voltage input to the input terminal of the second light-emitting element group 220, reducing the adjustment range of the voltage conversion circuit 330 and lowering its adjustment difficulty. Furthermore, it improves the accuracy of the output voltage of the backlight driving circuit 300, thereby enhancing the display effect of the display device.

[0098] As shown in Figure 10, in some embodiments, the display device further includes a second feedback unit 500. The input terminal of the second feedback unit 500 is used to acquire a second control signal from the second light-emitting element group 220. The second feedback unit 500 is used to generate a first feedback signal 802 based on the second control signal. The voltage conversion circuit 330 is used to adjust the voltage output by the voltage conversion circuit 330 based on the first feedback signal 802. The transmission path of the first feedback signal 802 can be referred to Figure 9.

[0099] In some embodiments, the second feedback unit 500 can determine the fluctuation of the voltage signal output from the positive output terminal of the second secondary winding 322 based on the voltage signal output from the positive output terminal of the first secondary winding 321. Further, based on the voltage signal fluctuation, a first feedback signal 802 is generated so that the voltage output by the voltage conversion circuit 330 can compensate for the fluctuation of the voltage signal output from the positive output terminal of the second secondary winding 322, thereby accelerating the adjustment frequency of the voltage conversion circuit 330 and further improving the stability and accuracy of the input voltage at the input terminal of the second light-emitting element group 220.

[0100] As shown in Figure 11, when the backlight driving circuit 300 includes two voltage conversion circuits 330, the two voltage conversion circuits 330 can adjust the voltage according to different first feedback signals 802. Each voltage conversion circuit includes a DC-DC converter, a second secondary winding 322, and a first feedback signal 802. In the display device shown in Figure 11, the first feedback signal 801 (FB1) is used to control the duty cycle of the S1 and S2 switching transistors, further adjusting the input voltage of the primary winding 310 of the transformer bank, so that the output voltages of the first secondary winding 321 and the second secondary winding 322 change accordingly. Two second feedback signals 802 (FB2 and FB3) are used to adjust the output voltage of the two voltage conversion circuits 330 respectively, further improving the voltage output accuracy at different output terminals of the backlight driving circuit 300.

[0101] The display device provided in this application embodiment obtains a second control signal from the control terminal of the second light-emitting element group 220 through the input terminal of the second feedback unit 500. Based on the second control signal, the current light-emitting state of the second light-emitting element group 220 can be determined. Furthermore, the difference between the current light-emitting state and the target light-emitting state of the second light-emitting element group 220 can be determined, and a second feedback signal is generated based on this difference. This allows the voltage conversion circuit 330 to perform voltage conversion based on the voltage fluctuations of the secondary winding 320 of the transformer group. This ensures that the voltage output from the positive output terminal of the second secondary winding 322 and the voltage output from the output terminal of the voltage conversion circuit 330 meet the power supply voltage required by the second light-emitting element group 220. This accelerates the adjustment frequency of the voltage conversion circuit 330, further improving the stability and accuracy of the input voltage at the input terminal of the second light-emitting element group 220, and improving the accuracy of the output voltage of the backlight driving circuit 300, thereby improving the display effect and display quality of the display device.

[0102] In some embodiments, the first light-emitting element group 210 emits red light, and the second light-emitting element group 220 emits light in at least one of green and blue.

[0103] It should be noted that the power supply voltage required for a red-emitting light-emitting element group is approximately 2V, for a green-emitting light-emitting element group it is approximately 3V, and for a blue-emitting light-emitting element group it is approximately 3V to 3.3V. Therefore, the power supply voltage required for green and blue-emitting light-emitting element groups is relatively similar, while the power supply voltage required for red-emitting light-emitting element groups differs significantly from that required for green and blue light-emitting element groups.

[0104] It should be noted that the junction voltage of the red-emitting light-emitting element group is lower than that of the green and blue-emitting light-emitting element groups. Therefore, in order to balance the color temperature of the light-emitting element groups with different colors, it is necessary to increase the supply current of the red-emitting light-emitting element group.

[0105] As shown in Figure 12, when the display device includes the backlight module 200 and backlight driving circuit 300 as shown in Figure 11, the overall architecture of the display device also includes a lamp board, a main board, a main board power supply circuit, and a PFC power factor correction circuit. With a 220V AC mains input, the PFC power factor correction circuit performs voltage boosting and power factor correction. For the power supply output, the entire device requires three voltages: a backlight driving voltage, a 12V power supply voltage for the main board and other components, and an 18V audio power supply voltage. In the overall architecture shown in Figure 12, the power supply requires two LLC half-bridge resonant circuits. One circuit provides a constant voltage output with 12V as the feedback reference to ensure a stable 12V power supply output. The 18V power supply output is controlled only by the number of winding turns and does not require separate feedback.

[0106] The display device provided in this application embodiment sets the emission color of the first light-emitting element group 210 to red, so that the primary winding 310 of the transformer group can preferentially adjust the voltage output of the positive output terminal of the first secondary winding 321 according to the power supply voltage required by the first light-emitting element group 210, thereby meeting the power supply requirements of the red-emitting element group. Furthermore, by setting the emission color of the second light-emitting element group 220 to at least one of green and blue, the voltage input to the input terminal of the second light-emitting element group 220 can be coarsely adjusted using the transformer group, and then finely adjusted at high frequency using the voltage conversion circuit 330, to meet the power supply requirements of the light-emitting element group with at least one of green and blue emission colors. In addition, by simplifying the power transmission path of the red-emitting element group, the heat generated by current transmission can be further reduced, the color temperature of the light-emitting element groups with different emission colors within the backlight module 200 can be further balanced, and the display effect and display quality of the display device can be improved.

Claims

1. A display device, comprising: The display panel includes a light-emitting side and a light-receiving side; A backlight module is located on the light-incident side of the display panel. The backlight module includes at least a first light-emitting element group and a second light-emitting element group, wherein the first light-emitting element group includes a first light-emitting element, the second light-emitting element group includes a second light-emitting element, and the power supply voltage of the first light-emitting element group is not equal to the power supply voltage of the second light-emitting element group. Backlight driving circuit, the backlight driving circuit includes: A transformer bank includes a primary winding and at least two secondary windings. The at least two secondary windings include a first secondary winding and a second secondary winding. The positive output terminal of the first secondary winding is electrically connected to the first light-emitting element group, and the positive output terminal of the second secondary winding is electrically connected to the second light-emitting element group. At least one voltage conversion circuit, wherein the voltage conversion circuit and the second secondary winding are connected in series between the ground terminal and the second light-emitting element group, and the voltage conversion circuit is used to convert the input voltage; The first secondary winding is used to provide the power supply voltage for the first light-emitting element group, and the second secondary winding and the voltage conversion circuit connected in phase are used to jointly provide the power supply voltage for the second light-emitting element group.

2. The display device according to claim 1, wherein the voltage conversion circuit includes a voltage input terminal, the voltage input terminal being connected to the positive output terminal of the first secondary winding.

3. The display device according to claim 1, wherein the number of voltage conversion circuits in the backlight driving circuit is the same as the number of the second secondary winding; The second secondary winding corresponds to the voltage conversion circuit, and the backlight module includes at least two groups of the second light-emitting elements with different supply voltages; The positive output terminal of each of the second secondary windings is electrically connected to a group of the second light-emitting elements, and the negative output terminal of each of the second secondary windings is electrically connected to the output terminal of the voltage conversion circuit.

4. The display device according to claim 1, wherein the power supply voltage of the first light-emitting element group is less than the power supply voltage of the second light-emitting element group.

5. The display device according to claim 1, wherein a second secondary winding and a voltage conversion circuit are used to jointly provide power supply voltage for at least two groups of the second light-emitting elements.

6. The display device according to claim 1, wherein the backlight driving circuit includes one of the voltage conversion circuits, the transformer group includes at least two second secondary windings, and the backlight module includes at least two second light-emitting element groups with different supply voltages; Of at least two second secondary windings, at least one second secondary winding has its positive output terminal electrically connected to the second light-emitting element group whose power supply voltage is the first power supply voltage, and its negative output terminal electrically connected to the output terminal of the voltage conversion circuit; the positive output terminal of the remaining second secondary winding is electrically connected to one of the second light-emitting element groups whose power supply voltage is the second power supply voltage, and its negative output terminal is electrically connected to the output terminal of the voltage conversion circuit. in, The number of coil turns of each second secondary winding connected to the second light-emitting element group, which has a different supply voltage, is different.

7. The display device according to claim 1, wherein the transformer group comprises at least two first secondary windings; At least two positive output terminals of the first secondary windings are electrically connected to the first light-emitting element group; at least two positive output terminals of the first secondary windings are used to jointly provide the power supply current for the first light-emitting element group.

8. The display device according to claim 7, wherein the transformer group comprises at least two primary windings and at least two second secondary windings; Of the at least two primary windings, at least one primary winding is opposite to at least one first secondary winding and corresponds to a portion of a second secondary winding; the remaining primary winding corresponds to the remaining first secondary winding other than the at least one first secondary winding and corresponds to the remaining second portion of the winding other than the portion of the second secondary winding.

9. The display device according to claim 8, wherein at least two of the primary windings are connected in series; In at least two of the primary windings, the second light-emitting element group connected to the positive output terminal of the second secondary winding of at least one primary winding has a different power supply voltage than the second light-emitting element group connected to the positive output terminal of the second secondary winding of the remaining primary windings.

10. The display device according to claim 7, wherein the number of the first secondary windings is positively correlated with the power supply current of the first light-emitting element group.

11. The display device according to claim 1, further comprising: A first feedback unit, wherein the input terminal of the first feedback unit is used to acquire a first control signal from the first light-emitting element group, and the output terminal of the first feedback unit is electrically connected to the input terminal of the primary winding of the transformer group, the first feedback unit being used to provide a first feedback signal according to the first control signal, the first feedback signal being used to adjust the voltage of the primary winding of the transformer group; and / or, The second feedback unit has an input terminal for acquiring a second control signal from the second light-emitting element group, and an output terminal for being electrically connected to the voltage conversion circuit. The second feedback unit is used to generate a second feedback signal based on the second control signal, and the voltage conversion circuit is used to adjust the voltage output by the voltage conversion circuit based on the second feedback signal.

12. The display device according to any one of claims 1 to 11, wherein the light emission color of the first light-emitting element in the first light-emitting element group is red, and the light emission color of the first light-emitting element in the second light-emitting element group is at least one of green and blue.

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