A power supply circuit and a display device

Abstract

This application discloses a power supply circuit and a display device. The power supply circuit includes an LLC control module, a first rectification and filtering module, and a backlight control module. The LLC control module outputs a first supply voltage with positive and negative cycles and a second supply voltage with a positive half-cycle based on the input voltage. The first rectification and filtering module is connected to the LLC control module and the backlight strip. The first rectification and filtering module rectifies and filters the first supply voltage to power the backlight strip. The backlight control module samples the current of the backlight strip and adjusts the current of the backlight strip based on the sampling results. This application can meet the requirements of high-power display devices while simplifying the power supply architecture, which is beneficial for reducing costs.

Description

Technical Field

[0001] This application relates to the field of electronic technology, specifically to a power supply circuit and a display device. Background Technology

[0002] LED backlighting is used in various display devices, and an adjustable and stable output current is required when using LEDs, such as in television backlighting. The power supply design for a television needs to output at least two sets of voltages: one set is a stable voltage for the chassis and other circuits, and the other set is a stable current for the backlight.

[0003] Current power supply architectures typically use one power supply to provide one voltage to the chassis, while another power supply, after being stepped down or stepped up, powers the backlight. However, this architecture is only suitable for devices with low to medium power requirements and cannot meet high-power demands. For high-power applications, a separate power module is often used to power the chassis, and another separate power module is needed to directly power the backlight. However, using two separate power modules undoubtedly increases the complexity of the power supply architecture and raises costs.

[0004] Therefore, the technology still needs to be improved and enhanced. Utility Model Content

[0005] This application provides a power supply circuit and a display device that can meet the requirements of high-power display devices while simplifying the power supply architecture, thereby reducing costs.

[0006] This application provides a power supply circuit for use in a display device, the display device including multiple backlight strips, the power supply circuit including:

[0007] The LLC control module is used to output a first supply voltage with positive and negative cycles and a second supply voltage with positive half-cycles based on the input voltage.

[0008] The first rectification and filtering module is connected to the LLC control module and the backlight strip; the first rectification and filtering module is used to rectify and filter the first power supply voltage to power the backlight strip.

[0009] The backlight control module is connected to the backlight strip; the backlight control module is used to sample the current of the backlight strip and adjust the current of the backlight strip according to the sampling results.

[0010] In some embodiments of the power supply circuit, the power supply circuit further includes:

[0011] The second rectification and filtering module is connected to the LLC control module and is used to rectify and filter the second power supply voltage.

[0012] The third rectification and filtering module is connected to the LLC control module and the backlight strip;

[0013] The LLC control module is also used to output the third power supply voltage for the positive half-cycle; the third rectification and filtering module is used to rectify and filter the third power supply voltage to power the backlight strip.

[0014] In some embodiments of the power supply circuit, the power supply circuit further includes an isolation module, which is connected to the LLC control module and the first rectifier and filter module respectively; the isolation module is used to isolate the DC voltage between the LLC control module and the first rectifier and filter module.

[0015] In some embodiments of the power supply circuit, the LLC control module includes a switching unit and an LLC conversion unit, the switching unit being connected to the LLC conversion unit; the LLC conversion unit is connected to the first rectification and filtering module, the second rectification and filtering module, and the third rectification and filtering module, respectively.

[0016] The switching unit is used to output a primary voltage with positive and negative cycles according to the input voltage; the LLC conversion unit is used to output a first supply voltage, a second supply voltage, and a third supply voltage according to the primary voltage.

[0017] In some embodiments of the power supply circuit, the LLC converter unit includes a resonant transformer, a primary winding of the resonant transformer and a switching unit, and a secondary winding of the resonant transformer including a first winding, a second winding and a third winding. One end of the first winding is connected to an isolation module, and the other end of the first winding is connected to a first rectifier and filter module. One end of the second winding is connected to a second rectifier and filter module, and the other end of the second winding is grounded. One end of the third winding is connected to a third rectifier and filter module, and the other end of the third winding is grounded.

[0018] In some embodiments of the power supply circuit, the isolation module includes a first capacitor, one end of which is connected to one end of a first winding, and the other end of which is connected to a first rectifier and filter module.

[0019] In some embodiments of the power supply circuit, the backlight strip includes five channels, and the first rectifier and filter module includes a first diode, a second diode, a third diode, a fourth diode, a second capacitor, and a third capacitor.

[0020] The cathode of the first diode and the anode of the second diode are both connected to the other end of the first capacitor. The anode of the first diode is connected to one end of the second capacitor and the cathode of the first light strip. The anode of the first light strip is connected to the cathode of the second light strip. The anode of the second light strip is connected to the backlight control module. The cathode of the second diode is connected to one end of the third capacitor and the anode of the third light strip. The cathode of the third light strip is connected to the anode of the fourth light strip. The cathode of the fourth light strip is connected to the other end of the third capacitor and the anode of the third diode. The cathode of the third diode and the anode of the fourth diode are both connected to the LLC control module. The cathode of the fourth diode is connected to the other end of the second capacitor and the anode of the fifth light strip. The cathode of the fifth light strip is connected to the backlight control module.

[0021] In some embodiments of the power supply circuit, the backlight control module includes a controller, a switching transistor, a sampling resistor, an inductor, and a fourth capacitor. The first terminal of the switching transistor is connected to the controller, the second terminal of the switching transistor is connected to one end of the sampling resistor, one end of the sampling resistor is connected to the controller, and the other end of the sampling resistor is grounded. The third terminal of the switching transistor is connected to one end of the inductor and the positive terminal of the second light strip, and the other end of the inductor is connected to the negative terminal of the fifth light strip. One end of the fourth capacitor is connected to the other end of the inductor, and the other end of the fourth capacitor is grounded.

[0022] In some embodiments of the power supply circuit, the backlight control module further includes a fifth diode, the positive terminal of which is connected to one end of an inductor, and the negative terminal of which is connected to the positive terminal of the second light strip.

[0023] In some embodiments of the power supply circuit, the second rectifier and filter module includes a sixth diode and a fifth capacitor. The positive terminal of the sixth diode is connected to the LLC control module, the negative terminal of the sixth diode is used to connect to the downstream load, one end of the fifth capacitor is connected to the negative terminal of the sixth diode, and the other end of the fifth capacitor is grounded.

[0024] In some embodiments of the power supply circuit, the third rectifier and filter module includes a seventh diode and a sixth capacitor. The positive terminal of the seventh diode is connected to the LLC control module, the negative terminal of the seventh diode is connected to the positive terminal of the second street light strip, one end of the sixth capacitor is connected to the negative terminal of the seventh diode, and the other end of the sixth capacitor is grounded.

[0025] This application also provides a display device, which includes the power supply circuit described above.

[0026] This application provides a power supply circuit and a display device. The power supply circuit incorporates a single LLC control module to simultaneously power multiple backlight strips and downstream loads in the display device, reducing the need for independent power supply modules such as the LLC control module. This simplifies the power supply circuit structure and saves costs. Furthermore, the inclusion of the LLC control module in the power supply circuit integrates an LLC topology on top of the single power supply module, enabling the power supply circuit to meet high-power consumption demands. Attached Figure Description

[0027] The technical solution and other beneficial effects of this application will become apparent from the following detailed description of specific embodiments in conjunction with the accompanying drawings.

[0028] Figure 1 This is a first structural block diagram of a power supply circuit provided in an embodiment of this application.

[0029] Figure 2 This is a second structural block diagram of the power supply circuit provided in an embodiment of this application.

[0030] Figure 3 This is a structural block diagram of the LLC control module in the power supply circuit provided in an embodiment of this application.

[0031] Figure 4 This is a structural diagram of the resonant transformer in the power supply circuit provided in an embodiment of this application.

[0032] Figure 5 A circuit diagram of the power supply circuit provided in an embodiment of this application. Detailed Implementation

[0033] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0034] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Features thus defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0035] Please see Figure 1This application provides a power supply circuit 30, which is applied in a display device. The display device includes multiple backlight strips 10 and a downstream load 20. The power supply circuit 30 can be used to power the multiple backlight strips 10 and the downstream load 20. The downstream load 20 can be a chassis board in the display device. In this embodiment, the power supply circuit 30 can simultaneously power the backlight strips 10 and the chassis board.

[0036] Specifically, the power supply circuit 30 includes a primary control module 31, an LLC control module 32, a first rectifier and filter module 33, and a backlight control module 34. The primary control module 31 is connected to the LLC control module 32. The LLC control module 32 is connected to the first rectifier and filter module 33 and the subsequent load 20, respectively. The first rectifier and filter module 33 is also used to connect to multiple backlight strips 10. The backlight control module 34 is also connected to the backlight strips 10.

[0037] The primary control module 31 provides an input voltage to the LLC control module 32 based on the input power supply. The input voltage output from the primary control module 31 to the LLC control module 32 can be two signals with opposite voltages. The LLC control module 32 outputs a first supply voltage with positive and negative cycles and a second supply voltage with a positive half-cycle based on the input voltage. The first rectification and filtering module 33 rectifies and filters the first supply voltage to power the backlight strip 10 in the display device. The second supply voltage powers the downstream load 20 in the display device. The backlight control module 34 samples the current of the backlight strip 10 and adjusts the current of the backlight strip 10 based on the sampling results.

[0038] It should be understood that the primary control module 31 is existing technology, and its function and connection method will not be described in detail here. In this embodiment, multiple backlight strips 10 and downstream loads 20 in the display device share a single LLC control module 32 to obtain power, thereby simplifying the structure of the power supply circuit 30, reducing the use of independent power modules such as the LLC control module 32, and saving costs. At the same time, by setting the LLC control module 32 in the power supply circuit 30, the power supply circuit 30 integrates an LLC topology on the basis of using a single power module, so that the power supply circuit 30 can meet the power demand of high power consumption.

[0039] Please see Figure 2In some embodiments, the power supply circuit 30 further includes a second rectification and filtering module 35 and a third rectification and filtering module 36. The second rectification and filtering module 35 is connected to the LLC control module 32 and is used to rectify and filter the second power supply voltage. The third rectification and filtering module 36 is connected to the LLC control module 32 and the backlight strip 10. The LLC control module 32 is also used to output a third power supply voltage for the positive half-cycle. The third rectification and filtering module 36 is used to rectify and filter the third power supply voltage to power the backlight strip 10. That is, in this embodiment, the LLC control module 32 can provide the first power supply voltage and the third power supply voltage to the backlight strip 10 to ensure the operation of the backlight strip 10.

[0040] In some embodiments, the power supply circuit 30 further includes an isolation module 37, which is connected to the LLC control module 32 and the first rectifier and filter module 33 respectively. The isolation module 37 is used to isolate the DC voltage between the LLC control module 32 and the first rectifier and filter module 33. In this embodiment, by setting the isolation module 37 between the LLC control module 32 and the first rectifier and filter module 33, the purpose of DC isolation can be achieved through the isolation module 37.

[0041] Please see Figure 3 In some embodiments, the LLC control module 32 includes a switching unit 321 and an LLC conversion unit 322, with the switching unit 321 connected to the LLC conversion unit 322; the LLC conversion unit 322 is connected to the first rectifier and filter module 33 and the first rectifier and filter module 33 respectively; the switching unit 321 is used to output a primary voltage with positive and negative periods according to the input voltage; the LLC conversion unit 322 is used to output a first supply voltage and a second supply voltage according to the primary voltage.

[0042] It should be understood that the switching unit 321 in this embodiment is prior art, and its function and connection method will not be described in detail here. The switching unit 321 can be connected to two input voltages with opposite voltages, and provides a primary voltage to the LLC conversion unit 322 according to the two opposite input voltages, so as to provide power supply voltage to the backlight strip 10 and the subsequent load 20 after LLC conversion.

[0043] Please see Figure 4In one embodiment, the LLC converter unit 322 includes a resonant transformer T1, a primary winding of the resonant transformer T1 and a switching unit 321. The secondary winding of the resonant transformer T1 includes a first winding N1, a second winding N2, and a third winding N3. One end of the first winding N1 is connected to the isolation module 37, and the other end of the first winding N1 is connected to the first rectifier and filter module 33. One end of the second winding N2 is connected to the second rectifier and filter module 35, and the other end of the second winding N2 is grounded. One end of the third winding N3 is connected to the third rectifier and filter module 36, and the other end of the third winding N3 is grounded. Depending on the power supply requirements, the secondary side of the resonant transformer T1 can be equipped with three windings, and four pins are correspondingly led out from the secondary side of the resonant transformer T1. Among them, pin 4 of the resonant transformer T1 is connected to the second rectifier and filter module 35, pin 2 of the resonant transformer T1 is connected to the first rectifier and filter module 33 through the isolation module 37, pin 3 of the resonant transformer T1 is directly connected to the first rectifier and filter module 33, and pin 1 of the resonant transformer T1 is connected to the third rectifier and filter module 36.

[0044] In this embodiment, by setting a single resonant transformer T1 to output a first supply voltage, a second supply voltage, and a third supply voltage based on the primary voltage input by the switching unit 321, the power supply for the downstream load 20 and multiple backlight strips 10 in the display device can be met. Compared to setting multiple transformers, this simplifies the circuit structure and saves costs. Both ends of the first winding N1 are connected to the first rectifier and filter module 33, providing the first supply voltage for both positive and negative cycles. One end of the second winding N2 and the third winding N3 are grounded, thus providing the second and third supply voltages for the positive half-cycle, respectively.

[0045] Please see Figure 5 In one embodiment, the isolation module 37 includes a first capacitor C1, one end of which is connected to the secondary winding of the resonant transformer T1 (e.g., pin 2 of the resonant transformer T1), and the other end of a second capacitor C2 is connected to the first rectifier and filter module 33. In this embodiment, by setting the first capacitor C1, the purpose of blocking DC current can be achieved, ensuring the passage of AC voltage and improving the stability of the power supply circuit 30.

[0046] As one embodiment, the backlight strip 10 includes five paths, each with multiple light-emitting diodes connected in series. The first rectification and filtering module 33 includes four diodes for rectification and two capacitors for filtering. Two diodes share one capacitor, which reduces the number of electronic components, simplifies the circuit structure, and saves costs. Specifically, the first rectification and filtering module 33 includes a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, a second capacitor C2, and a third capacitor C3. The cathode of the first diode D1 and the anode of the second diode D2 are both connected to the other end of the first capacitor C1. The anode of the first diode D1 is connected to one end of the second capacitor C2 and the cathode of the first light strip (L11~L1n). The anode of the first light strip (L11~L1n) is connected to the cathode of the second light strip (L21~L2n). The anode of the second light strip (L21~L2n) is connected to the backlight control module 34. The cathode of the second diode D2 is connected to one end of the third capacitor C3 and the anode of the third light strip (L31~L3n). The third light strip (L11~L1n) is connected to the backlight control module 34. The negative terminal of L31 to L3n is connected to the positive terminal of the fourth light strip (L41 to L4n). The negative terminal of the fourth light strip (L41 to L4n) is connected to the other end of the third capacitor C3 and the positive terminal of the third diode D3. The negative terminal of the third diode D3 and the positive terminal of the fourth diode D4 are both connected to the LLC control module 32 (such as pin 3 of the resonant transformer T1). The negative terminal of the fourth diode D4 is connected to the other end of the second capacitor C2 and the positive terminal of the fifth light strip (L51 to L5n). The negative terminal of the fifth light strip (L51 to L5n) is connected to the backlight control module 34.

[0047] As one embodiment, the backlight control module 34 includes a controller 341, a switching transistor Q1, a sampling resistor R1, an inductor L0, and a fourth capacitor C4. The first end of the switching transistor Q1 is connected to the controller 341, the second end of the switching transistor Q1 is connected to one end of the sampling resistor R1, one end of the sampling resistor R1 is connected to the controller 341, and the other end of the sampling resistor R1 is grounded. The third end of the switching transistor Q1 is connected to one end of the inductor L0 and the positive terminal of the second light strip, and the other end of the inductor L0 is connected to the negative terminal of the fifth light strip. One end of the fourth capacitor C4 is connected to the other end of the inductor L0, and the other end of the fourth capacitor C4 is grounded.

[0048] In this embodiment, the switching transistor Q1 can be a MOSFET, with its first terminal serving as the gate, its second terminal as the source, and its third terminal as the drain. The controller 341 samples the current of one of the multiple backlight strips 10, such as the fifth strip (L51-L5n), through the sampling resistor R1. Based on the sampled current, the controller controls the duty cycle of the switching transistor Q1 to adjust the voltage of the fourth capacitor C4, thereby adjusting the voltage of the backlight strip 10 and ultimately regulating its current.

[0049] In another embodiment, the backlight control module 34 further includes a fifth diode D5. The positive terminal of the fifth diode D5 is connected to one end of the inductor L0, and the negative terminal of the fifth diode D5 is connected to the positive terminal of the second light strip. In this embodiment, the fifth diode D5 serves as a freewheeling diode, providing a freewheeling path for the current in the inductor L0 when the switch Q1 is off, preventing reverse current from damaging the circuit.

[0050] In one embodiment, the second rectifier-filter module 35 includes a sixth diode D6 and a fifth capacitor C5. The positive terminal of the sixth diode D6 is connected to pin 4 of the LLC control module 32, such as the resonant transformer T1, and the negative terminal of the sixth diode D6 is connected to the subsequent load 20. One end of the fifth capacitor C5 is connected to the negative terminal of the sixth diode D6, and the other end of the fifth capacitor C5 is grounded. In this embodiment, the sixth diode D6 is a rectifier diode, and the fifth capacitor C5 is a filter capacitor.

[0051] In one embodiment, the third rectifier and filter module 36 includes a seventh diode D7 and a sixth capacitor C6. The positive terminal of the seventh diode D7 is connected to pin 1 of the LLC control module 32 (e.g., the resonant transformer T1), and the negative terminal of the seventh diode D7 is connected to the positive terminal of the second street light strip. One end of the sixth capacitor C6 is connected to the negative terminal of the seventh diode D7, and the other end of the sixth capacitor C6 is grounded. Similarly, in this embodiment, the seventh diode D7 is a rectifier diode, and the sixth capacitor C6 is a filter capacitor.

[0052] Please continue reading. Figures 1 to 5 The working principle of power supply circuit 30 is as follows:

[0053] The two opposite input voltages output from the primary control module 31 cause the secondary side of the resonant transformer T1 to output a supply voltage with positive and negative cycles. The power supply path during the positive half-cycle is shown by the solid line in the figure; when the resonant transformer T1 is in the positive half-cycle, the secondary side of the resonant transformer T1 outputs from pin 2, passing through the first capacitor C1 to the second diode D2 to charge the third capacitor C3. The power supply path during the negative half-cycle is shown by the dashed line in the figure; when the resonant transformer T1 is in the negative half-cycle, the secondary side of the resonant transformer T1 charges the second capacitor C2 from pin 3 through the fourth diode D4.

[0054] The DC current path in the circuit is from the first light strip (L11~L1n), the second light strip (L21~L2n), the third light strip (L31~L3n), the fourth light strip (L41~L4n), to the fifth light strip (L51~L5n), forming a path through Q1 and R1. The controller 341 obtains the current of the fifth light strip by sampling the voltage across the sampling resistor R1, thereby adjusting the duty cycle of the switching transistor Q1 to regulate the voltage of the fourth capacitor C4, achieving constant current. Due to the DC blocking effect of the first capacitor C1, the currents of the first diode D1, the second diode D2, the third diode D3, and the fourth diode D4 are equal, and the four diodes are connected in series. Therefore, the current of all five light strips is equal, so sampling the current value of only one light strip is sufficient to ensure that the other four light strips also have the same constant current.

[0055] This application embodiment also provides a display device, which includes the power supply circuit described above. The LLC control module in the power supply circuit outputs a supply voltage with positive and negative cycles based on the input voltage. After rectification and filtering, the voltage simultaneously supplies power to multiple backlight strips and subsequent loads. The backlight control module enables constant current control of the backlight strips. Since the power supply circuit has been described in detail above, it will not be repeated here.

[0056] The power supply circuit and display device provided in this application can simultaneously power multiple backlight strips and subsequent loads using a single resonant transformer. Compared to using multiple transformers for power supply, this simplifies the power supply structure and reduces costs. Furthermore, by employing an LLC topology, this power supply circuit can meet the high power requirements of a television set.

[0057] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0058] The power supply circuits provided in the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the technical solutions and core ideas of this application. Those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A power supply circuit, applied in a display device, the display device comprising a plurality of backlight strips, characterized in that, The power supply circuit includes: LLC control module, the LLC control module is used to output a first supply voltage with positive and negative cycles and a second supply voltage with positive half-cycle according to the input voltage; A first rectification and filtering module is connected to the LLC control module and the backlight strip; the first rectification and filtering module is used to rectify and filter the first power supply voltage to supply power to the backlight strip; A backlight control module is provided, which is connected to the backlight strip. The backlight control module is used to sample the current of the backlight strip and adjust the current of the backlight strip according to the sampling result.

2. The power supply circuit according to claim 1, characterized in that, The power supply circuit also includes: The second rectification and filtering module is connected to the LLC control module and is used to rectify and filter the second power supply voltage. The third rectification and filtering module is connected to the LLC control module and the backlight strip; the LLC control module is also used to output the third power supply voltage of the positive half cycle; the third rectification and filtering module is used to rectify and filter the third power supply voltage to power the backlight strip.

3. The power supply circuit according to claim 2, characterized in that, The power supply circuit also includes an isolation module, which is connected to the LLC control module and the first rectifier and filter module respectively; the isolation module is used to isolate the DC voltage between the LLC control module and the first rectifier and filter module.

4. The power supply circuit according to claim 3, characterized in that, The LLC control module includes a switching unit and an LLC conversion unit, the switching unit being connected to the LLC conversion unit; the LLC conversion unit is connected to the first rectification and filtering module, the second rectification and filtering module, and the third rectification and filtering module, respectively. The switching unit is used to output a primary voltage with positive and negative cycles according to the input voltage; the LLC conversion unit is used to output the first supply voltage, the second supply voltage and the third supply voltage according to the primary voltage.

5. The power supply circuit according to claim 4, characterized in that, The LLC converter unit includes a resonant transformer. The primary winding of the resonant transformer is connected to the switching unit. The secondary winding of the resonant transformer includes a first winding, a second winding, and a third winding. One end of the first winding is connected to the isolation module, and the other end of the first winding is connected to the first rectifier and filter module. One end of the second winding is connected to the second rectifier and filter module, and the other end of the second winding is grounded. One end of the third winding is connected to the third rectifier and filter module, and the other end of the third winding is grounded.

6. The power supply circuit according to claim 5, characterized in that, The isolation module includes a first capacitor, one end of which is connected to one end of the first winding, and the other end of which is connected to the first rectifier and filter module.

7. The power supply circuit according to any one of claims 2-6, characterized in that, The backlight strip includes five channels, and the first rectifier and filter module includes a first diode, a second diode, a third diode, a fourth diode, a second capacitor, and a third capacitor; The negative terminal of the first diode and the positive terminal of the second diode are both connected to the LLC control module. The positive terminal of the first diode is connected to one end of the second capacitor and the negative terminal of the first light strip. The positive terminal of the first light strip is connected to the negative terminal of the second light strip. The positive terminal of the second light strip is connected to the backlight control module. The negative terminal of the second diode is connected to one end of the third capacitor and the positive terminal of the third light strip. The negative terminal of the third light strip is connected to the positive terminal of the fourth light strip. The negative terminal of the fourth light strip is connected to the other end of the third capacitor and the positive terminal of the third diode. The negative terminals of the third diode and the positive terminals of the fourth diode are both connected to the LLC control module. The negative terminal of the fourth diode is connected to the other end of the second capacitor and the positive terminal of the fifth light strip. The negative terminal of the fifth light strip is connected to the backlight control module.

8. The power supply circuit according to claim 7, characterized in that, The backlight control module includes a controller, a switching transistor, a sampling resistor, an inductor, and a fourth capacitor. The first terminal of the switching transistor is connected to the controller, the second terminal of the switching transistor is connected to one end of the sampling resistor, one end of the sampling resistor is connected to the controller, and the other end of the sampling resistor is grounded. The third terminal of the switching transistor is connected to one end of the inductor and the positive terminal of the second light strip, and the other end of the inductor is connected to the negative terminal of the fifth light strip. One end of the fourth capacitor is connected to the other end of the inductor, and the other end of the fourth capacitor is grounded.

9. The power supply circuit according to claim 8, characterized in that, The backlight control module also includes a fifth diode, the positive terminal of which is connected to one end of the inductor, and the negative terminal of which is connected to the positive terminal of the second light strip.

10. The power supply circuit according to claim 7, characterized in that, The second rectifier and filter module includes a sixth diode and a fifth capacitor. The positive terminal of the sixth diode is connected to the LLC control module, the negative terminal of the sixth diode is used to connect to the downstream load, one end of the fifth capacitor is connected to the negative terminal of the sixth diode, and the other end of the fifth capacitor is grounded.

11. The power supply circuit according to claim 9, characterized in that, The third rectifier and filter module includes a seventh diode and a sixth capacitor. The positive terminal of the seventh diode is connected to the LLC control module, the negative terminal of the seventh diode is connected to the positive terminal of the second street light strip, one end of the sixth capacitor is connected to the negative terminal of the seventh diode, and the other end of the sixth capacitor is grounded.

12. A display device, characterized in that, The display device includes a power supply circuit as described in any one of claims 1-11.

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