LED drive circuit with high power factor

Abstract

The utility model provides an LED drive circuit with a high power factor. The LED drive circuit comprises a power factor boosting module and an LED module. The power factor boosting module comprises a first diode, a first capacitor, a first electrolytic capacitor and a first resistor; one end of the first capacitor is connected with the cathode of the first diode and one end of the first resistor. The other end of the first capacitor is respectively connected with the anode of the first diode, the other end of the first resistor and the anode of the first electrolytic capacitor, and the anode of the first electrolytic capacitor is grounded; one end of the first capacitor is further used for being connected with a direct-current input power source and the input end of the LED module. According to the LED circuit, the first diode, the first capacitor, the first electrolytic capacitor and the first resistor form the power factor boosting module, and compared with the mode that the power factor of the circuit is improved through a power factor chip, the LED circuit power factor boosting module plays a role in boosting the power factor of the LED circuit, the problem of chip failure caused by surge impact does not exist, and the design cost of the LED circuit is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of high power factor circuits, and particularly to an LED driving circuit with a high power factor. Background Art

[0002] In order to increase the power factor of traditional intelligent LED lights to above 0.7, a dedicated PF (Power Factor) boosting chip needs to be used. However, using a PF boosting chip has problems such as high chip cost, many peripheral circuits, and easy chip failure due to surge impact.

[0003] For example, using a linear power supply scheme with power factor boosting, the defect of this scheme is that the chip with PF boosting function has a high cost, serious chip heating and low reliability during use, and there is also a risk of surge failure in the use scenario of high-voltage input. Another example is using a switching power supply scheme with power factor correction, and the defect of this scheme is that both the chip cost and the overall material cost are very high. Summary of the Utility Model

[0004] The technical problem to be solved by the utility model is: to provide an LED driving circuit with a high power factor to improve the power factor of intelligent LED lights in a low-cost manner.

[0005] In order to solve the above technical problem, the technical scheme adopted by the utility model is:

[0006] An LED driving circuit with a high power factor includes a power factor boosting module and an LED module; the power factor boosting module includes a first diode, a first capacitor, a first electrolytic capacitor and a first resistor; one end of the first capacitor is respectively connected to the negative electrode of the first diode and one end of the first resistor; the other end of the first capacitor is respectively connected to the positive electrode of the first diode, the other end of the first resistor and the positive electrode of the first electrolytic capacitor, and the positive electrode of the first electrolytic capacitor is grounded; one end of the first capacitor is also used for connecting to a DC input power supply and the input end of the LED module.

[0007] Further, it further includes an input rectification module; the input end of the input rectification module is used for connecting to an AC input power supply; the output end of the input rectification module is respectively connected to one end of the first capacitor, the negative electrode of the first diode, one end of the first resistor and the input end of the LED module.

[0008] Further, it further includes a varistor; the varistor is connected to the input end of the input rectification module.

[0009] Further, it further includes a radio frequency module and a power supply module; the input end of the power supply module is connected to the output end of the input rectification module; the output end of the power supply module is connected to the power supply input end of the radio frequency module; the output end of the radio frequency module is connected to the control input end of the LED module; the control output end of the radio frequency module is used to receive radio frequency signals.

[0010] Further, it further includes a second diode and a third diode; the output end of the input rectification module is respectively connected to the positive electrode of the second diode and the positive electrode of the third diode; the negative electrode of the second diode is connected to the input end of the power supply module; the negative electrode of the third diode is respectively connected to one end of the first capacitor, the negative electrode of the first diode, one end of the first resistor, and the input end of the LED module.

[0011] Further, the power supply module includes a first inductor, a second resistor, a second electrolytic capacitor, and a power supply chip; one end of the first inductor is respectively connected to one end of the second resistor and the output end of the input rectification module; the other end of the first inductor is respectively connected to the other end of the second resistor, the positive electrode of the second electrolytic capacitor, and the input end of the power supply chip; the output end of the power supply chip is connected to the power supply input end of the radio frequency module.

[0012] Further, the model of the power supply chip includes BP2571X.

[0013] Further, the LED module includes a control unit and at least two kinds of light sources; the power supply input end of the control unit is connected to the output end of the input rectification module; the output end of the control unit is respectively connected to different light sources.

[0014] Further, the control unit includes a chip with dimming and / or color mixing functions.

[0015] Further, the radio frequency module includes a radio frequency chip or a micro control chip.

[0016] The beneficial effects of the present utility model are as follows: The power factor improvement module is formed by discrete devices, namely the first diode, the first capacitor, the first electrolytic capacitor, and the first resistor. Compared with improving the power factor of the circuit through a power factor chip, it not only plays a role in improving the power factor of the LED circuit, but also does not have the problem of chip failure caused by surge impact, and at the same time reduces the design cost of the LED circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a module schematic diagram of a high power factor LED driving circuit in an embodiment of the present utility model;

[0018] Figure 2Schematic diagram of the connection of a high power factor LED driving circuit in an embodiment of the present invention;

[0019] Figure 3 Schematic diagram of the connection of the input rectification module in a high power factor LED driving circuit in an embodiment of the present invention;

[0020] Figure 4 Schematic diagram of the connection of the power factor improvement module in a high power factor LED driving circuit in an embodiment of the present invention;

[0021] Figure 5 Schematic diagram of the connection of the power supply module and the radio frequency module in a high power factor LED driving circuit in an embodiment of the present invention;

[0022] Label description:

[0023] 1. Power factor improvement module; 2. LED module; 3. Input rectification module; 4. Radio frequency module; 5. Power supply module; D1. First diode; D2. Second diode; D3. Third diode; C1. First capacitor; E1. First electrolytic capacitor; E2. Second electrolytic capacitor; R1. First resistor; R2. Second resistor; RV1. Varistor; L1. First inductor; IC1. Power supply chip; IC2. Control unit; BR1. Rectifier bridge. Specific implementation manners

[0024] To describe in detail the technical content, achieved purpose and effects of the present invention, the following is described in conjunction with the implementation manners and accompanied by the drawings.

[0025] Please refer to Figure 1 , a high power factor LED driving circuit, including a power factor improvement module and an LED module; the power factor improvement module includes a first diode, a first capacitor, a first electrolytic capacitor and a first resistor; one end of the first capacitor is respectively connected to the negative electrode of the first diode and one end of the first resistor; the other end of the first capacitor is respectively connected to the positive electrode of the first diode, the other end of the first resistor and the positive electrode of the first electrolytic capacitor, and the positive electrode of the first electrolytic capacitor is grounded; one end of the first capacitor is also used to be connected to a DC input power supply and the input end of the LED module.

[0026] It can be seen from the above description that the beneficial effects of the present invention are as follows: By using discrete devices, namely the first diode, the first capacitor, the first electrolytic capacitor and the first resistor, to form the power factor improvement module, compared with improving the power factor of the circuit through a power factor chip, it not only plays the role of improving the power factor of the LED circuit, but also there is no problem of chip failure caused by surge impact, and at the same time, the design cost of the LED circuit is reduced.

[0027] Further, it further includes an input rectification module; the input end of the input rectification module is used to connect to an AC input power supply; the output end of the input rectification module is respectively connected to one end of the first capacitor, the negative electrode of the first diode, one end of the first resistor, and the input end of the LED module.

[0028] As can be seen from the above description, by setting the input rectification module, the input alternating current can be converted into direct current to supply power to the subsequent circuit modules.

[0029] Further, it further includes a varistor; the varistor is connected to the input end of the input rectification module.

[0030] As can be seen from the above description, by setting the varistor at the input end of the input rectification module, voltage clamping can be performed when the circuit withstands overvoltage, absorbing excess current to protect the circuit.

[0031] Further, it further includes a radio frequency module and a power supply module; the input end of the power supply module is connected to the output end of the input rectification module; the output end of the power supply module is connected to the power supply input end of the radio frequency module; the output end of the radio frequency module is connected to the control input end of the LED module; the control output end of the radio frequency module is used to receive radio frequency signals.

[0032] As can be seen from the above description, by setting the radio frequency module and the power supply module, signal transmission can be performed through radio frequency control methods such as remote control, realizing the control of the LED module.

[0033] Further, it further includes a second diode and a third diode; the output end of the input rectification module is respectively connected to the positive electrode of the second diode and the positive electrode of the third diode; the negative electrode of the second diode is connected to the input end of the power supply module; the negative electrode of the third diode is respectively connected to one end of the first capacitor, the negative electrode of the first diode, one end of the first resistor, and the input end of the LED module.

[0034] As can be seen from the above description, by setting the second diode and the third diode at the input end of the power supply module and the output end of the input rectification module, the power supply module can be isolated from the power factor improvement module to avoid interference.

[0035] Further, the power supply module includes a first inductor, a second resistor, a second electrolytic capacitor, and a power supply chip; one end of the first inductor is respectively connected to one end of the second resistor and the output end of the input rectification module; the other end of the first inductor is respectively connected to the other end of the second resistor, the positive electrode of the second electrolytic capacitor, and the input end of the power supply chip; the output end of the power supply chip is connected to the power supply input end of the RF module. Among them, the model of the power supply chip includes BP2571X.

[0036] As can be seen from the above description, by setting the first inductor, the second resistor, and the second electrolytic capacitor, the voltage at the output end of the input rectification module can be converted into the voltage required by the power supply chip, so that the power supply chip can work more stably.

[0037] Further, the LED module includes a control unit and at least two types of light sources; the power supply input end of the control unit is connected to the output end of the input rectification module; the output end of the control unit is respectively connected to different light sources.

[0038] As can be seen from the above description, the LED module is composed of the control unit and at least two types of light sources. By controlling the control unit, different light sources can be combined into different light-emitting forms to achieve different light-emitting effects.

[0039] Further, the control unit includes a chip with dimming and / or color mixing functions.

[0040] As can be seen from the above description, the control unit can use a dimming chip, a color mixing chip, or a dimming and color mixing chip, that is, different chips can be selected according to specific design requirements to achieve corresponding functions.

[0041] Further, the RF module includes an RF chip or a microcontroller chip.

[0042] As can be seen from the above description, the RF module can use an RF chip or a microcontroller chip. The RF chip can achieve RF control at a lower cost; while the microcontroller chip can achieve more functions.

[0043] The high power factor LED drive circuit provided by the present invention can be applied to circuits that require improving the power factor, such as linear or switching schemes for LED drive circuits, which will be described below through specific embodiments:

[0044] Embodiment 1

[0045] Please refer to Figure 1 and Figure 2, A high power factor LED driver circuit, comprising a power factor improvement module 1, an LED module 2, an input rectification module 3, a radio frequency module 4, and a power supply module 5; the LED module 2 includes a control unit IC2 and at least two types of light sources; the power input terminal of the control unit IC2 is connected to the output terminal of the input rectification module 3; the output terminal of the control unit IC2 is respectively connected to different light sources; the control unit IC2 includes a chip with dimming and / or color mixing functions, for example, in this example, a dimming and color mixing chip with the model number BP5758 is adopted; at the same time, the light source can be monochromatic, bicolor or multi-channel color; for example, in this example, it includes a first light source GL1-GL4, a second light source BL1-BL4, a third light source RL1-RL4, a fourth light source CL1-CL4, and a fifth light source WL1-WL4. The radio frequency module 4 includes a radio frequency chip or a micro control chip, for example, a radio frequency module with the model number CBU is adopted, or a main control chip such as an MCU can also be adopted to provide dimming and color mixing instructions for the dimming and color mixing circuit; in this embodiment, a dimming and color mixing signal is generated by a radio frequency module with the model number CBU.

[0046] Please refer to Figure 3 , The input end of the input rectification module 3 is used to connect to an AC input power supply; the output end of the input rectification module 3 is respectively connected to one end of a first capacitor C1, the negative electrode of a first diode D1, one end of a first resistor R1, and the input end of the LED module 2; among them, a varistor RV1 is further included; the varistor RV1 is connected to the input end of the input rectification module 3; the input rectification module 3 includes a rectifier bridge BR1; after the AC input passes through the varistor RV1 and the rectifier bridge BR1 for rectification, the AC is converted into a positive current. At the same time, a second diode D2 and a third diode D3 are further provided at the output end of the rectifier bridge BR1; the output end of the input rectification module 3 is respectively connected to the negative electrode of the second diode D2 and the positive electrode of the third diode D3; the negative electrode of the second diode D2 is connected to the input end of the power supply module 5; the negative electrode of the third diode D3 is respectively connected to one end of the first capacitor C1, the negative electrode of the first diode D1, one end of the first resistor R1, and the input end of the LED module 2; isolating the rectification circuit, the power supply module 5, and the power factor improvement module 1.

[0047] Please refer to Figure 4 , The power factor improvement module 1 includes a first diode D1, a first capacitor C1, a first electrolytic capacitor E1, and a first resistor R1; one end of the first capacitor C1 is respectively connected to the negative electrode of the first diode D1 and one end of the first resistor R1; the other end of the first capacitor C1 is respectively connected to the positive electrode of the first diode D1, the other end of the first resistor R1, and the positive electrode of the first electrolytic capacitor E1, and the positive electrode of the first electrolytic capacitor E1 is grounded; one end of the first capacitor C1 is connected to the output end of the rectifier bridge BR1 and the input end of the LED module 2.

[0048] The specific working principle of the power factor improvement module 1 is as follows:

[0049] At the moment of power-on, the positive current passes through the third diode D3. At this time, the first capacitor C1 is short-circuited to pre-charge the first electrolytic capacitor E1, which serves the purpose of protecting the first resistor R1 and avoiding overvoltage failure of the first resistor R1 caused by the high voltage at the moment of charging the first electrolytic capacitor E1; when the first electrolytic capacitor E1 completes pre-charging, the positive current charges the first electrolytic capacitor E1 through the first resistor R1; the first resistor R1 with a relatively large resistance slows down the time for the first electrolytic capacitor E1 to complete charging, enabling the charging current to follow the charging voltage to achieve the purpose of PF improvement; after the first electrolytic capacitor E1 completes charging, it supplies power to the subsequent dimming and color mixing circuit through the first diode D1.

[0050] Please refer to Figure 5 , the input end of the power supply module 5 is connected to the output end of the input rectification module 3, that is, connected to the output end of the rectifier bridge BR1; the output end of the power supply module 5 is connected to the power supply input end of the radio frequency module 4; the output end of the radio frequency module 4 is connected to the control input end of the LED module 2; the control output end of the radio frequency module 4 is used to receive radio frequency signals; in this embodiment, the power supply module 5 is a buck-type switching power supply, and the model of the power supply chip IC1 is the BP2571X chip. In other alternative embodiments, it can also be other conventional power supply schemes, and its function is to provide a working power supply for the radio frequency module 4; among them, the peripheral circuit of the power supply module 5 includes the first inductor L1, the second resistor R2, the second electrolytic capacitor E2, and the power supply chip IC1; one end of the first inductor L1 is respectively connected to one end of the second resistor R2 and the output end of the input rectification module 3; the other end of the first inductor L1 is respectively connected to the other end of the second resistor R2, the positive electrode of the second electrolytic capacitor E2, and the input end of the power supply chip IC1; the output end of the power supply chip IC1 is connected to the power supply input end of the radio frequency module 4; at the same time, the power supply module 5 also includes other peripheral devices such as capacitors, capacitors, and inductors to enable the circuit to work normally.

[0051] The above are only the embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in the related technical field, shall be equally included in the patent protection scope of the present invention.

Claims

1. An LED driving circuit with a high power factor, characterized in that, It includes a power factor improvement module and an LED module; The power factor improvement module includes a first diode, a first capacitor, a first electrolytic capacitor and a first resistor; One end of the first capacitor is respectively connected to the negative electrode of the first diode and one end of the first resistor; The other end of the first capacitor is respectively connected to the positive electrode of the first diode, the other end of the first resistor and the positive electrode of the first electrolytic capacitor, and the positive electrode of the first electrolytic capacitor is grounded; One end of the first capacitor is also used to connect to a DC input power supply and the input end of the LED module.

2. The high power factor LED driving circuit according to claim 1, wherein It also includes an input rectification module; The input end of the input rectification module is used to connect to an AC input power supply; The output end of the input rectification module is respectively connected to one end of the first capacitor, the negative electrode of the first diode, one end of the first resistor and the input end of the LED module.

3. The LED driving circuit with a high power factor according to claim 2, characterized in that It also includes a varistor; The varistor is connected to the input end of the input rectification module.

4. The high-power factor LED driving circuit according to claim 2, wherein, It also includes a radio frequency module and a power supply module; The input end of the power supply module is connected to the output end of the input rectification module; The output end of the power supply module is connected to the power supply input end of the radio frequency module; The output end of the radio frequency module is connected to the control input end of the LED module; The control output end of the radio frequency module is used to receive radio frequency signals.

5. The LED driving circuit with a high power factor according to claim 4, wherein, It also includes a second diode and a third diode; The output end of the input rectification module is respectively connected to the positive electrode of the second diode and the positive electrode of the third diode; The negative electrode of the second diode is connected to the input end of the power supply module; The negative electrode of the third diode is respectively connected to one end of the first capacitor, the negative electrode of the first diode, one end of the first resistor and the input end of the LED module.

6. The LED driving circuit with a high power factor according to claim 4, characterized in that, The power supply module includes a first inductor, a second resistor, a second electrolytic capacitor and a power supply chip; One end of the first inductor is respectively connected to one end of the second resistor and the output end of the input rectification module; The other end of the first inductor is respectively connected to the other end of the second resistor, the positive electrode of the second electrolytic capacitor and the input end of the power supply chip; The output end of the power supply chip is connected to the power supply input end of the radio frequency module.

7. The LED driving circuit with a high power factor according to claim 6, characterized in that The model of the power supply chip includes BP2571X.

8. A high power factor LED driving circuit according to claim 4, characterized in that, The LED module includes a control unit and at least two types of light sources; The power supply input end of the control unit is connected to the output end of the input rectification module; The output end of the control unit is respectively connected to different light sources.

9. The LED driving circuit with a high power factor according to claim 8, characterized in that, The control unit includes a chip with dimming or / and color mixing functions.

10. A high power factor LED driving circuit according to claim 4, characterized in that, The radio frequency module includes a radio frequency chip or a micro control chip.

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