A non-isolated LED power supply, dimming power supply and lighting system

Abstract

This invention relates to the field of LED power supply technology, specifically to a non-isolated LED power supply, a dimming power supply, and a lighting system. The non-isolated LED power supply includes: an input rectifier and filter circuit, comprising a common-mode inductor, a differential-mode inductor, and a rectifier bridge; a power factor correction circuit, comprising a constant voltage chip and a boost inductor; a load output circuit, comprising a protection resistor and two output ports for supplying power to the LED; and a high-voltage constant current circuit, comprising a constant current chip and a grounding resistor for outputting current to the load output circuit. This invention designs a novel LED power supply topology. Compared to conventional circuits, the high-voltage constant current circuit of this invention has no external components such as electrolytic capacitors and inductors. This reduces the need for electrolytic capacitors, output inductors, and other auxiliary circuits compared to traditional circuits, thus not only reducing the design space requirements of the high-voltage constant current circuit but also eliminating additional EMC interference.

Description

Technical Field

[0001] This invention relates to the field of LED power supply technology, and in particular to a non-isolated LED power supply, a dimming power supply, and a lighting system. Background Technology

[0002] In the field of modern lighting technology, LEDs (light-emitting diodes) have become the mainstream light source replacing traditional incandescent and fluorescent lamps due to their significant advantages such as high luminous efficiency, long lifespan, energy saving, and environmental friendliness. As a core component of LED lighting systems, the performance of the constant current driver directly determines the luminous quality, operational stability, and lifespan of the luminaire. To ensure that LED light sources maintain consistent brightness under a wide range of input voltage fluctuations, the industry generally adopts a constant current control strategy to construct the driver circuit. However, traditional constant current driving schemes have revealed many irreconcilable contradictions in practical applications, especially in the selection of circuit topology. To achieve stable current output and ripple suppression, designers often have to rely on the collaborative work of discrete passive components such as electrolytic capacitors and power inductors. While this design approach is technically feasible, its inherent physical limitations are increasingly becoming a bottleneck restricting the development of LED power supplies towards higher performance.

[0003] Specifically, while the introduction of electrolytic capacitors can smooth out the pulsating DC current after rectification to some extent and effectively reduce the ripple coefficient of the output current, thus ensuring the stable operation of the LED chip, the physical characteristics of electrolytic capacitors themselves bring about significant negative effects. Electrolytic capacitors contain volatile electrolytes, and their lifespan is greatly affected by ambient temperature. In high-temperature operating environments, the electrolyte dries up faster, easily leading to capacitance decay or even failure, which in turn causes the entire driver power supply to malfunction. This creates a clear bottleneck effect compared to the ultra-long lifespan of LED light sources. More importantly, electrolytic capacitors are relatively large, occupying considerable physical space inside the power supply, severely limiting the evolution of LED driver power supplies towards miniaturization and compactness, making it difficult for the power supply to be adapted to embedded lamps or miniaturized lighting devices with strict size requirements. Meanwhile, while the use of power inductors helps to build efficient switching topologies, the inductor coils are prone to generating electromagnetic radiation during high-frequency switching, becoming one of the main sources of electromagnetic interference (EMI). Conducted and radiated interference generated by the circuit itself often pollutes the power grid environment, interferes with the normal operation of surrounding electronic equipment, and makes it difficult for the power supply's electromagnetic compatibility (EMC) performance to meet increasingly stringent international standards, such as CISPR 15 or EN 61000 series specifications. Furthermore, to address the EMC issues caused by inductors, designers typically need to add complex filtering circuits and shielding measures, which not only further increases the bill of materials cost but also makes the circuit structure increasingly bulky, and the overall efficiency decreases due to additional losses. Therefore, the current constant current drive architecture, which relies excessively on electrolytic capacitors and power inductors, is actually trapped in a vicious cycle of "sacrificing lifespan and size for stability, and sacrificing cost and efficiency for interference suppression." It struggles to achieve an ideal balance between the three key indicators of miniaturization, long lifespan, and high EMC, and can no longer fully meet the higher requirements of future intelligent and integrated lighting systems for drive power supplies. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing constant current driven LED power supplies, which increase the size of the LED power supply and reduce the electromagnetic compatibility of the LED power supply due to the use of electrolytic capacitors, inductors and other devices to build the constant current circuit. The invention provides a non-isolated LED power supply, a dimming power supply and a lighting system.

[0005] In a first aspect, the present invention provides a non-isolated LED power supply, comprising: an input rectifier and filter circuit, a power factor correction circuit, a load output circuit, and a high-voltage constant current circuit. The input rectifier and filter circuit includes at least a common-mode inductor, a differential-mode inductor, and a rectifier bridge. The power factor correction circuit includes at least a constant voltage chip and a boost inductor. The load output circuit includes a protection resistor and two output ports for connecting an LED and supplying power to the LED. The high-voltage constant current circuit includes a constant current chip and a grounding resistor for outputting current to the load output circuit.

[0006] According to a preferred embodiment, the load output circuit has two output ports, one a positive output port and the other a negative output port. The positive output port and the negative output port are connected through a protective resistor.

[0007] According to a preferred embodiment, the positive output of the power factor correction circuit is connected to the positive output port of the load output circuit. The negative output of the power factor correction circuit is connected to the negative output port of the load output circuit through the high-voltage constant current circuit.

[0008] According to a preferred embodiment, the high-voltage constant current circuit includes a plurality of constant current chips. Each constant current chip is configured with a grounding resistor. The plurality of constant current chips are connected in parallel with each other.

[0009] According to a preferred embodiment, the constant current chip is an LED linear constant current control chip.

[0010] According to a preferred embodiment, the system further includes an auxiliary power supply circuit and a dimming signal module. The auxiliary power supply circuit is electrically connected to the dimming signal module. The input of the auxiliary power supply circuit is connected to the output of the input rectifier and filter circuit. The PWM pin of the dimming signal module is connected to the PWM pin of the LED linear constant current control chip.

[0011] In a second aspect, the present invention provides a lighting system including an LED load and an LED power supply. The LED power supply employs a non-isolated LED power supply provided by the present invention.

[0012] In a third aspect, the present invention provides a dimming power supply, comprising: an input rectifier and filter circuit, a power factor correction circuit, a load output circuit, and a high-voltage constant current circuit. The input rectifier and filter circuit includes at least a common-mode inductor, a differential-mode inductor, and a rectifier bridge. The power factor correction circuit includes at least a constant voltage chip and a boost inductor. The load output circuit includes a protection resistor and two output ports for connecting LEDs and supplying power to the LEDs. The high-voltage constant current circuit includes a constant current chip and a grounding resistor for outputting current to the load output circuit. The constant current chip is an LED linear constant current control chip.

[0013] In a fourth aspect, the present invention provides a lighting system including an LED load and a dimming power supply. The dimming power supply is a dimming power supply provided by the present invention.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0015] This invention provides a non-isolated LED power supply. By designing a novel LED power supply topology, when setting up a high-voltage constant current circuit, compared with conventional general circuits, the high-voltage constant current circuit of this invention has no external components such as electrolytic capacitors and inductors. Compared with traditional circuits, it reduces the number of components such as electrolytic capacitors and output inductors and auxiliary circuits, which not only reduces the design space requirements of the high-voltage constant current circuit, but also does not generate additional EMC interference. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a non-isolated LED power supply module according to a preferred embodiment of the present invention.

[0017] Figure 2 This is a circuit diagram of the non-isolated LED power supply involved in Example 2.

[0018] Figure 3 This is a circuit diagram of the non-isolated LED power supply involved in Example 3.

[0019] Figure 4 This is a circuit diagram of the non-isolated LED power supply involved in Example 4. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to specific embodiments. However, this should not be construed as limiting the scope of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0021] Unless otherwise specified, the terms "upper," "lower," "left," "right," "center," "inner," and "outer," etc., used in the description of specific embodiments of the present invention to indicate orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationship in which the product / equipment / device is usually placed during use. These terms are merely for the purpose of facilitating the description of the present invention or simplifying the description in specific embodiments, and for enabling those skilled in the art to quickly understand the solution, and do not indicate or imply that a particular device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on the present invention.

[0022] Furthermore, the use of terms such as "horizontal," "vertical," "suspended," "parallel," and "coaxial" does not imply that the corresponding device / component / element must be absolutely horizontal, vertical, suspended, parallel, or coaxial. Slight tilt or deviation is permissible, as long as it does not affect the normal function of the relevant component. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," not that the structure must be perfectly horizontal; a slight tilt is acceptable. "Coaxial" means that two components are arranged as coaxially as possible, allowing them to move coaxially or approximately coaxially when their relative positions change. Alternatively, it can be simplified to mean that the corresponding device / component / element, when arranged in "horizontal," "vertical," "suspended," "parallel," or "coaxial" directions, can have an error / deviation of ±10% relative to the corresponding direction, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, and more preferably within ±4%. For example, the deviation in the "coaxial" direction is controlled within 0.2-1mm, preferably within 0.2-0.5mm. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its function in the solution of the present invention.

[0023] Furthermore, the use of terms such as "first," "second," and "third" in terminology is merely for distinguishing descriptions of identical or similar components and should not be interpreted as emphasizing or implying the relative importance of a particular component.

[0024] Furthermore, in the description of the embodiments of the present invention, "several", "more than", and "a number of" represent at least two. The number can be any number, such as two, three, four, five, six, seven, eight, or nine, and can even exceed nine.

[0025] Furthermore, in the description of the technical solution of this invention, unless otherwise explicitly specified / limited / restricted, the terms "set up," "install," "connect," "link," "provided with," "laid out," and "arranged" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to connection methods commonly used in the art, such as welding, riveting, bolting, and threaded connections. Such connections can be mechanical, electrical, or communication connections; they can be direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components.

[0026] Example 1 This embodiment provides a non-isolated LED power supply. See also... Figure 1 The non-isolated LED power supply includes: an input rectifier and filter circuit, a power factor correction circuit, a load output circuit, and a high-voltage constant current circuit.

[0027] The input rectifier and filter circuit includes at least a common-mode inductor, a differential-mode inductor, and a rectifier bridge. The power factor correction circuit includes at least a constant-voltage chip and a boost inductor. The load output circuit includes a protection resistor and two output ports for connecting and powering an LED. The high-voltage constant-current circuit includes a constant-current chip and a grounding resistor for outputting current to the load output circuit.

[0028] This embodiment provides a non-isolated LED power supply. By designing a novel LED power supply topology, when setting up a high-voltage constant current circuit, compared with conventional general circuits, the high-voltage constant current circuit of this invention has no external components such as electrolytic capacitors and inductors. Compared with traditional circuits, it reduces the number of components such as electrolytic capacitors and output inductors and auxiliary circuits, which not only reduces the design space requirements of the high-voltage constant current circuit, but also does not generate additional EMC interference.

[0029] Example 2 This embodiment is a further explanation of embodiment 1, and the content is repeated and will not be repeated.

[0030] See Figure 2 The input rectifier and filter circuit includes an AC input port, a common-mode inductor L1, a differential-mode inductor, a rectifier bridge DB1, and a differential-mode inductor L2. Specifically, the AC live wire port L is connected to one end of a varistor RV1 via a fuse F1, and the other end of the varistor RV1 is connected to the AC neutral wire port N. The two input terminals of the common-mode inductor L1 are connected to the two ends of the varistor RV1. The rectifier bridge DB1 consists of four diodes, including two AC input terminals, one DC positive output terminal, and one DC negative output terminal. The two output terminals of the common-mode inductor L1 are connected to the two AC input terminals of the rectifier bridge DB1; and the two output terminals of the common-mode inductor L1 are also connected to the two ends of a capacitor CX1. The DC negative output terminal of the rectifier bridge DB1 is connected to ground GND. The DC positive output terminal of the rectifier bridge DB1 is connected to one end of the differential-mode inductor L2, and the other end of the differential-mode inductor L2 serves as the output terminal of the input rectifier and filter circuit, connected to the power factor correction circuit. A resistor R1 is connected in parallel with the differential-mode inductor L2. One end of capacitor C1 is connected to ground (GND), and the other end is connected to the positive DC output terminal of rectifier bridge DB1 via resistor R1. The input voltage of the input rectifier and filter circuit can be 120 / 220V AC.

[0031] See Figure 2The power factor correction circuit includes at least a constant voltage chip and a boost inductor. The constant voltage chip is a BP2636. The DRAIN pin of the constant voltage chip is connected to one end of the boost inductor T1, and the other end of the boost inductor T1 is connected to the output of the input rectifier filter circuit. Resistors R2 and R3 are connected in series, with one end connected to the output of the input rectifier filter circuit and the other end connected to the VCC pin of the constant voltage chip. Diode D2 and capacitor C4 are connected in parallel. The cathode of diode D2 is connected to the cathode of diode D1, and the anode of diode D2 is connected to the output of the input rectifier filter circuit. The anode of diode D1 is connected to the DRAIN pin of the constant voltage chip. The cathode of diode D1 is connected to the anode of electrolytic capacitor EC1, and the cathode of electrolytic capacitor EC1 is connected to ground (GND). The anode of electrolytic capacitor EC1 is connected to one end of resistor R8, the other end of resistor R8 is connected to one end of resistor R7, the other end of resistor R7 is connected to one end of resistor R6, and the other end of resistor R6 is connected to the FB pin of the constant voltage chip. Resistors R6, R7, and R8 are connected in series. Resistor R5 and capacitor C3 are connected in parallel, with one end connected to the FB pin of the constant voltage chip and the other end connected to ground (GND). The GND pin of the constant voltage chip is grounded to GND. The CS pin of the constant voltage chip is grounded to GND through resistor R4. One end of capacitor C4 is connected to the VCC pin of the constant voltage chip, and the other end is grounded. The power factor correction circuit performs post-correction, achieving a power factor of 0.95; it can also boost the rectified high-voltage DC, raising it from 220V to approximately 400V.

[0032] See Figure 2 The load output circuit includes a protection resistor R1 and two output ports (LED+ and LED-) for connecting and powering an LED. Preferably, one output port of the load output circuit is the positive output port LED+, and the other is the negative output port LED-. The positive output port LED+ and the negative output port LED- are connected through the protection resistor R1. The positive output port LED+ is connected to the negative terminal of diode D2 in the power factor correction circuit. Preferably, the positive terminal of diode D2 in the power factor correction circuit serves as the positive output port of the power factor correction circuit.

[0033] See Figure 2 A high-voltage constant current circuit, including a constant current chip and a grounding resistor, is used to output current to the load output circuit. The constant current chip used is BP5116. The GND pin of the constant current chip is grounded to GND. The CS pin of the constant current chip is grounded to GND through the grounding resistor RS1. The OUT pin of the constant current chip is connected to the negative output port LED-.

[0034] Preferably, the positive output of the power factor correction circuit is connected to the positive output port LED+ of the load output circuit. The negative output of the power factor correction circuit is connected to the negative output port LED- of the load output circuit through a high-voltage constant current circuit.

[0035] Example 3 This embodiment is a further explanation of Embodiment 2.

[0036] Preferably, the input rectifier filter circuit can be replaced with other circuits capable of filtering and rectifying the input AC power, and the power factor correction circuit can be replaced with other circuits built based on constant voltage chips.

[0037] See Figure 3 The input rectifier and filter circuit can be composed of components such as fuses, varistors, common-mode inductors, differential-mode inductors, safety capacitors, rectifier bridges, and CBB capacitors, and is an EMC input rectifier and filter circuit that can adapt to three-phase AC input.

[0038] See Figure 3 The power factor correction circuit can be an APFC power factor correction circuit composed of a constant voltage chip BP2639A, a boost inductor, and other related peripheral circuit devices, used to generate a constant DC voltage to supply the subsequent circuit.

[0039] The positive output of the power factor correction circuit is connected to the positive output port LED+ of the load output circuit. The negative output of the power factor correction circuit is connected to the negative output port LED- of the load output circuit through a high-voltage constant current circuit.

[0040] Preferably, the high-voltage constant current circuit may include a plurality of constant current chips. Each constant current chip is configured with a grounding resistor. The plurality of constant current chips are connected in parallel with each other.

[0041] See Figure 3 Preferably, the high-voltage constant current circuit includes four constant current chips U2, U3, U4, and U5, and four grounding resistors RS3, RS4, RS5, and RS6. The OUT pins of constant current chips U2, U3, U4, and U5 are all connected to the negative output port LED- of the load output circuit. The GND pins of constant current chips U2, U3, U4, and U5 are all connected to ground GND. The CS pins of constant current chips U2, U3, U4, and U5 are each connected to ground GND through a grounding resistor. The CS pin of constant current chip U2 is connected to ground GND through grounding resistor RS4. The CS pin of constant current chip U3 is connected to ground GND through grounding resistor RS5. The CS pin of constant current chip U4 is connected to ground GND through grounding resistor RS6. The CS pin of constant current chip U5 is connected to ground GND through grounding resistor RS3.

[0042] Example 4 This embodiment is a further explanation of Embodiment 2.

[0043] Preferably, the constant current chip in the high-voltage constant current circuit can be an LED linear constant current control chip. More preferably, the LED linear constant current control chip can be an SM2611EN.

[0044] See Figure 4 Preferably, the OUT pin of the LED linear constant current control chip is connected to the negative output port LED- of the load output circuit. The CS pin of the LED linear constant current control chip is connected to ground GND through a grounding resistor RS1. The GND pin of the LED linear constant current control chip is connected to the negative output of the power factor correction circuit, i.e., connected to ground GND. The VIN pin of the LED linear constant current control chip is connected to the positive output of the input rectifier filter circuit. Preferably, the positive output of the input rectifier filter circuit is led out to the HV port. The HV port is not only connected to the VIN pin of the LED linear constant current control chip, but can also be connected to the auxiliary power supply circuit.

[0045] The auxiliary power supply circuit consists of an IC chip, an inductor L3, and related peripheral components. Preferably, the IC chip is a non-isolated buck constant voltage control chip, used to provide 3.3V or 5V auxiliary power.

[0046] See Figure 4 The IC chip used is SDH7252. The DRAIN pin of the IC chip is connected to the anode of diode D3. The cathode of diode D3 is connected to the HV port. The CS pin of the IC chip is connected to the GND pin through resistor R10. The SEL pin of the IC chip is connected to the GND pin. The anode of capacitor EC4 is connected to the cathode of diode D3, and the cathode of capacitor EC4 is connected to ground (GND). The anode of diode D6 is connected to ground (GND). The cathode of diode D6 is connected to the GND pin of the IC chip. One end of capacitor C5 is connected to the GND pin of the IC chip, and the other end is connected to the VCC pin of the IC chip. One end of inductor L3 is connected to the GND pin of the IC chip, and the other end is connected to the anode of diode D5. The cathode of diode D5 is connected to the VCC pin of the IC chip. The anode of capacitor EC2 is connected to the anode of diode D5, and the cathode of capacitor EC2 is connected to the GND pin of the IC chip. Resistor R18 is connected in parallel with capacitor EC2.

[0047] The output of the auxiliary power supply circuit is connected to the dimming signal module.

[0048] See Figure 4 The positive output of the auxiliary power supply circuit can be led out from the positive terminal of diode D5 and connected to the VCC port of the dimming signal module through device B1; the negative output of the auxiliary power supply circuit, i.e., ground GND, is connected to the GND port of the dimming signal module.

[0049] See Figure 4The PWM port of the dimming signal module is connected to the DIM pin of the LED linear constant current control chip through resistor R12.

[0050] Preferably, the dimming signal module can be an existing Bluetooth dimming module, rotary dimming module, etc. An auxiliary power supply circuit can power the dimming signal module.

[0051] The dimming signal module generates a PWM dimming signal, which is transmitted to the DIM pin of the LED linear constant current control chip. Upon receiving the PWM signal, the LED linear constant current control chip adjusts its internal reference voltage according to the PWM signal duty cycle, thereby regulating the output current and achieving dimming. The high-voltage constant current circuit eliminates external components such as electrolytic capacitors and inductors, thus avoiding additional EMC interference. It also saves PCB design space (reducing electrolytic capacitors, output inductors, and their associated circuitry compared to traditional circuits, saving approximately 30% of space), reduces costs by over 30%, lowers debugging difficulty and costs, and shrinks the LED power supply PCB board size by about half, facilitating product miniaturization.

[0052] Example 5 This embodiment provides a lighting system, including an LED load and an LED power supply. Preferably, the LED power supply in this embodiment can be any of the non-isolated LED power supplies described in embodiments 1 to 4.

[0053] Example 6 This embodiment provides a dimming power supply. See also... Figure 4 Preferably, the dimming power supply includes: an input rectifier and filter circuit, a power factor correction circuit, a load output circuit, a high-voltage constant current circuit, an auxiliary power supply circuit, and a dimming signal module.

[0054] The input rectifier and filter circuit includes at least a common-mode inductor, a differential-mode inductor, and a rectifier bridge.

[0055] A power factor correction circuit includes at least a constant voltage chip and a boost inductor.

[0056] The load output circuit includes a protection resistor and two output ports for connecting LEDs and supplying power to them.

[0057] A high-voltage constant current circuit, including a constant current chip and a grounding resistor, is used to output current to the load output circuit. The constant current chip can be an LED linear constant current control chip.

[0058] The auxiliary power supply circuit consists of an IC chip, inductor L3, and related peripheral components.

[0059] The dimming signal module can use existing Bluetooth dimming modules, knob dimming modules, etc.

[0060] The output of the auxiliary power supply circuit is connected to the dimming signal module to supply power to the dimming signal module.

[0061] The dimming signal module generates a PWM signal and sends it to the LED linear constant current control chip.

[0062] The dimming signal module generates a PWM dimming signal, which is transmitted to the DIM pin of the LED linear constant current control chip. Upon receiving the PWM signal, the LED linear constant current control chip adjusts its internal reference voltage according to the PWM signal duty cycle, thereby regulating the output current and achieving high-voltage constant current dimming. The high-voltage constant current circuit eliminates the need for external components such as electrolytic capacitors and inductors, thus avoiding additional EMC interference. It also saves PCB design space (reducing electrolytic capacitors, output inductors, and their associated circuitry compared to traditional circuits, saving approximately 30% of space), reduces costs by over 30%, lowers debugging difficulty and costs, and shrinks the LED power supply PCB board size by about half, facilitating product miniaturization.

[0063] Example 7 This embodiment provides a lighting system, including an LED load and a dimming power supply. Preferably, the dimming power supply in this embodiment is a dimming power supply according to Embodiment 6.

[0064] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A non-isolated LED power supply, characterized in that, include: The input rectifier and filter circuit includes at least a common-mode inductor, a differential-mode inductor, and a rectifier bridge. A power factor correction circuit includes at least a constant voltage chip and a boost inductor; The load output circuit includes a protection resistor and two output ports for connecting LEDs and powering them; A high-voltage constant current circuit, including a constant current chip and a grounding resistor, is used to output current to the load output circuit.

2. The non-isolated LED power supply according to claim 1, characterized in that, The load output circuit has two output ports, one of which is a positive output port and the other is a negative output port. The positive output port and the negative output port are connected through a protection resistor.

3. A non-isolated LED power supply according to claim 2, characterized in that, The positive output of the power factor correction circuit is connected to the positive output port of the load output circuit; the negative output of the power factor correction circuit is connected to the negative output port of the load output circuit through the high-voltage constant current circuit.

4. A non-isolated LED power supply according to claim 3, characterized in that, The high-voltage constant current circuit includes several constant current chips; each constant current chip is equipped with a grounding resistor; the several constant current chips are connected in parallel with each other.

5. A non-isolated LED power supply according to claim 3, characterized in that, The constant current chip is an LED linear constant current control chip.

6. A non-isolated LED power supply according to claim 5, characterized in that, It also includes an auxiliary power supply circuit and a dimming signal module; The auxiliary power supply circuit is electrically connected to the dimming signal module; The input of the auxiliary power supply circuit is connected to the output of the input rectifier and filter circuit; The PWM pin of the dimming signal module is connected to the PWM pin of the LED linear constant current control chip.

7. A lighting system comprising an LED load and an LED power supply, characterized in that, The LED power supply is a non-isolated LED power supply as described in any one of claims 1 to 6.

8. A dimming power supply, characterized in that, include: The input rectifier and filter circuit includes at least a common-mode inductor, a differential-mode inductor, and a rectifier bridge. A power factor correction circuit includes at least a constant voltage chip and a boost inductor; The load output circuit includes a protection resistor and two output ports for connecting LEDs and powering them; A high-voltage constant current circuit, including a constant current chip and a grounding resistor, is used to output current to the load output circuit.

9. A dimming power supply according to claim 8, characterized in that, The constant current chip is an LED linear constant current control chip.

10. A lighting system comprising an LED load and a dimming power supply, characterized in that, The dimming power supply is a dimming power supply as described in claim 8 or 9.

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