Switching power supply device and lighting lamp

Abstract

The utility model discloses a switching power supply device and an illuminating lamp, the switching power supply device comprises a power supply board, and the power supply board is welded on a light circuit board through a bonding pad and is electrically connected with the light circuit board; a rectifying circuit, a first filter circuit, a constant-current driving circuit and an output circuit are arranged on the power panel; the rectification circuit is connected with the constant current drive circuit and the output circuit through the first filter circuit, and is used for converting an externally input alternating current into a direct current, and adaptively supplying power to the constant current drive circuit and the output circuit after filtering. The constant-current driving circuit is connected with a light source circuit on the lamplight circuit board through the output circuit and used for driving the light source circuit to work in a constant-current mode. According to the utility model, the EMC interference problem can be efficiently solved, the whole circuit structure is simple, the cost is low, and the actual production requirements of users are met.

Description

Technical Field

[0001] The utility model relates to the technical field of lighting power supplies, in particular to a switching power supply device and a lighting fixture. Background Art

[0002] With the rapid development and innovation of LED lighting technology, the performance and quality requirements of products are getting higher and higher. Especially for lighting products; currently, most of the lighting products represented by domestic downlights are linear power supplies. The disadvantage of linear power supplies is that they have poor surge resistance and high quality risks when used in engineering channels. If the linear power supply is changed to a switching power supply and a DOB full-chip design is used on an aluminum substrate (lighting circuit board), the product quality and reliability can be greatly improved. However, the disadvantage of this design is that EMC is very difficult to handle. Due to the leakage current of the aluminum substrate and the possible differences between different batches, if a high-frequency switching power supply is placed on the aluminum substrate, there will be relatively large interference between the AC / DC circuits, poor stability, and difficult to handle EMC interference, affecting the normal use of the lamp.

[0003] In order to solve the EMC problem of this type of design on the market, a large number of anti-interference components (such as common-mode inductors, capacitors and magnetic rings, etc.) are often stacked to suppress EMC, resulting in a more complex power supply structure, high product production costs, and failure to meet user production needs. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a switching power supply device and a lighting fixture, which can effectively solve the EMC interference problem, and the overall circuit structure is simple and low in cost, meeting the actual production needs of users.

[0005] In order to solve the above technical problems, the utility model provides a switching power supply device, including a power supply board, which is welded on a lighting circuit board through a welding pad and electrically connected to the lighting circuit board; a rectifier circuit, a first filter circuit, a constant current drive circuit and an output circuit are provided on the power supply board; the rectifier circuit is respectively connected to the constant current drive circuit and the output circuit through the first filter circuit, and is used to convert external input alternating current into direct current, and adapt power supply to the constant current drive circuit and the output circuit after filtering; the constant current drive circuit is connected to the light source circuit on the lighting circuit board through the output circuit, and is used to drive the light source circuit to operate at a constant current.

[0006] As an improvement on the above scheme, the power board is provided with at least a power live wire pad, a power neutral wire pad, a first connecting pad and a second connecting pad, and the lighting circuit board is provided with a mounting pad which is welded and connected to the power live wire pad, the power neutral wire pad, the first connecting pad and the second connecting pad in a one-to-one correspondence; the power live wire pad and the power neutral wire pad are respectively connected to the rectifier circuit and are respectively welded to the corresponding terminals of the external AC power supply; the first connecting pad and the second connecting pad are respectively connected to the output circuit and are respectively connected to the light source circuit through the mounting pads.

[0007] As an improvement of the above scheme, the rectifier circuit includes a fuse resistor, a varistor and a rectifier bridge; the first AC input end of the rectifier bridge is connected to the live wire pad of the power supply through the fuse resistor, and the second AC input end of the rectifier bridge is connected to the neutral wire pad of the power supply; the first DC output end of the rectifier bridge is connected to the first filter circuit and grounded through the varistor, the second DC output end of the rectifier bridge is grounded, and the varistor is connected in parallel with the first filter circuit.

[0008] As an improvement of the above scheme, the first filtering circuit includes a first inductor, a first resistor, a first electrolytic capacitor and a second electrolytic capacitor; one end of the first inductor is respectively connected to the output end of the rectifier circuit, one end of the first resistor and the positive terminal of the first electrolytic capacitor, and the other end of the first inductor is respectively connected to the other end of the first resistor, the positive terminal of the second electrolytic capacitor, the constant current drive circuit and the output circuit; the negative terminal of the first electrolytic capacitor is connected to the negative terminal of the second electrolytic capacitor and is grounded.

[0009] As an improvement of the above scheme, the constant current drive circuit includes a second inductor, a sampling module, a first capacitor, a second filter circuit and a constant current drive chip, and the constant current drive chip includes a power supply pin, an output pin, a sampling pin and a ground pin; the power supply pin is respectively connected to the first filter circuit and the output circuit, the output pin is respectively connected to the output circuit and the second filter circuit through the second inductor, the sampling pin is connected to the output pin through the first capacitor and grounded through the sampling module, and the ground pin is grounded.

[0010] As an improvement of the above solution, the second filtering circuit includes a second resistor and a second capacitor; one end of the second resistor is connected to the second inductor and the output circuit respectively, and the other end of the second resistor is grounded via the second capacitor.

[0011] As an improvement of the above solution, the sampling module includes at least one sampling resistor.

[0012] As an improvement of the above scheme, the output circuit includes a third electrolytic capacitor and a third resistor; the positive terminal of the third electrolytic capacitor is respectively connected to the first filter circuit, the power supply pin and the first connecting pad, the negative terminal of the third electrolytic capacitor is respectively connected to the second inductor, the second filter circuit and the second connecting pad, and the third electrolytic capacitor is connected in parallel with the third resistor.

[0013] As an improvement of the above solution, the power live wire pad and the power neutral wire pad are both arranged at one end of the power board, and the first connecting pad and the second connecting pad are both arranged at the other end of the power board.

[0014] The utility model also provides a lighting fixture, comprising a lamp body, a lighting circuit board and the above-mentioned switching power supply device, wherein the switching power supply device and the lighting circuit board are packaged in the lamp body.

[0015] The beneficial effects of implementing the utility model are:

[0016] The utility model has a simple overall circuit structure. By independently arranging the switching power supply on the power supply board and welding it on the lighting circuit board, the two boards are independent of each other and electrically connected to realize lighting work, avoid the accumulation of a large number of electronic components, and reduce the difficulty of EMC solution. The filter circuit set up can effectively solve the EMC interference problem without adding a large number of anti-interference components (such as common-mode inductors, capacitors and magnetic rings, etc.), reducing the device cost and meeting the actual production needs of users. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the switching power supply device of the utility model;

[0018] Figure 2 It is an exploded structural diagram of the power board and the lighting circuit board of the utility model;

[0019] Figure 3 It is a circuit structure diagram of the switching power supply device of the utility model. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solutions and advantages of the utility model clearer, the utility model will be further described in detail below with reference to the accompanying drawings.

[0021] like Figure 1 As shown, a specific embodiment of the utility model provides a switching power supply device, including a power board 1, which is welded on a lighting circuit board 21 through a welding pad and electrically connected to the lighting circuit board 21. The lighting circuit board 21 is an aluminum substrate; the power board 1 is preferably a glass fiber board, but is not limited thereto.

[0022] The power board 1 is provided with a rectifier circuit 3, a first filter circuit 4, a constant current drive circuit 5 and an output circuit 6; the rectifier circuit 3 is connected to the constant current drive circuit 5 and the output circuit 6 respectively through the first filter circuit 4, and is used to convert the external input AC power into DC power, and adapt the power supply to the constant current drive circuit 5 and the output circuit 6 after filtering; the first filter circuit 4 can suppress circuit interference and effectively solve the EMC interference problem. The constant current drive circuit 5 is connected to the light source circuit 7 on the lighting circuit board 21 through the output circuit 6, and is used to drive the light source circuit 7 to work at a constant current to realize the lighting work of the lamp.

[0023] Specifically, Figure 2 As shown, the power board 1 is at least provided with a power live wire pad A1, a power neutral wire pad B1, a first connecting pad C1 and a second connecting pad D1, and the lighting circuit board 21 is provided with mounting pads (such as A, B, C and D) which are welded and connected to the power live wire pad A1, the power neutral wire pad B1, the first connecting pad C1 and the second connecting pad D1 in a one-to-one correspondence; the power live wire pad A1 and the power neutral wire pad B1 are respectively connected to the rectifier circuit 3 and are respectively welded to the corresponding terminals of the external AC power supply; the first connecting pad C1 and the second connecting pad D1 are respectively connected to the output circuit 6 and are respectively connected to the light source circuit 7 through the mounting pads, thereby realizing the electrical circuit connection of the power board 1, the external AC power supply and the lighting circuit board 21.

[0024] Preferably, the power live pad A1 and the power neutral pad B1 are both arranged at one end of the power board 1, and the first connection pad C1 and the second connection pad D1 are both arranged at the other end of the power board 1 to facilitate wiring and improve the overall layout aesthetics.

[0025] The utility model has a simple overall circuit structure. By independently setting the switching power supply on the power supply board 1 and welding it on the lighting circuit board 21, the two boards are independent of each other and electrically connected to achieve lighting work, and avoid the accumulation of a large number of electronic components, reducing the difficulty of EMC solution. The filter circuit set up can effectively solve the EMC interference problem without adding a large number of anti-interference components (such as common-mode inductors, capacitors and magnetic rings, etc.), reducing the device cost and meeting the actual production needs of users.

[0026] The following is a detailed description of the present invention in conjunction with a specific circuit diagram:

[0027] like Figure 3 As shown, Figure 3 The circuit structure diagram of the switching power supply device of the utility model is shown, and the rectifier circuit 3, the first filter circuit 4, the constant current drive circuit 5 and the output circuit 6 are described below respectively:

[0028] 1. Rectification circuit 3

[0029] The rectifier circuit 3 includes a fuse resistor FR1, a varistor VR1 and a rectifier bridge BD1; the first AC input end of the rectifier bridge BD1 is connected to the power live wire pad A1 (such as the L end) through the fuse resistor FR1, and the second AC input end of the rectifier bridge BD1 is connected to the power neutral wire pad B1 (such as the N end); the first DC output end of the rectifier bridge BD1 is connected to the first filter circuit 4 and grounded through the varistor VR1, the second DC output end of the rectifier bridge BD1 is grounded, and the varistor VR1 is connected in parallel with the first filter circuit 4. The rectifier circuit 3 can convert the input AC power into DC power to adapt the power supply to the subsequent circuit.

[0030] The provided fuse resistor FR1 and varistor VR1 can play a role in circuit protection and improve circuit safety.

[0031] 2. The first filter circuit 4

[0032] The first filter circuit 4 includes a first inductor L1, a first resistor R1, a first electrolytic capacitor EC1 and a second electrolytic capacitor EC2; one end of the first inductor L1 is respectively connected to the output end of the rectifier circuit 3, one end of the first resistor R1 and the positive terminal of the first electrolytic capacitor EC1, and the other end of the first inductor L1 is respectively connected to the other end of the first resistor R1, the positive terminal of the second electrolytic capacitor EC2, the constant current drive circuit 5 and the output circuit 6; the negative terminal of the first electrolytic capacitor EC1 is connected to the negative terminal of the second electrolytic capacitor EC2 and grounded. The first filter circuit 4 can filter the direct current output by the rectifier circuit 3 to suppress circuit interference and solve the circuit EMC problem; the overall circuit structure is simple, and there is no need to set a large number of anti-interference components (such as common mode inductors, capacitors and magnetic rings, etc.) to suppress EMC, reduce device costs, and meet the actual production needs of users.

[0033] 3. Constant current drive circuit 5

[0034] The constant current driving circuit 5 includes a second inductor L2, a sampling module 51, a first capacitor C2, a second filter circuit 52 and a constant current driving chip U1, wherein the constant current driving chip U1 includes a power supply pin HV, an output pin DRAIN, a sampling pin CS and a ground pin GND; the power supply pin HV is respectively connected to the first filter circuit 4 and the output circuit 6, and is used to receive a power supply so that the chip can be powered on. The output pin DRAIN is respectively connected to the output circuit 6 and the second filter circuit 52 through the second inductor L2, and is used to output a constant current signal to the output circuit 6 and the second filter circuit 52; the output circuit 6 is used to output the constant current signal to the light source circuit 7 to drive the light source circuit 7 to work; the second filter circuit 52 is used to perform secondary filtering on the circuit signal to improve the interference suppression effect, thereby further solving the EMC interference problem. The sampling pin CS is connected to the output pin DRAIN through the first capacitor and is grounded through the sampling module 51, and the ground pin GND is grounded.

[0035] The second filter circuit 52 includes a second resistor R3 and a second capacitor C1; one end of the second resistor R3 is connected to the second inductor L2 and the output circuit 6 respectively, and the other end of the second resistor R3 is grounded via the second capacitor C1. The circuit signal is filtered twice by the RC filter circuit to improve the interference suppression effect, thereby further solving the EMC interference problem.

[0036] Preferably, the sampling module 51 includes two sampling resistors (such as RS1 and RS2). The constant current driver chip U1 is externally connected to the sampling module 51 through the sampling pin CS, and the output constant current value can be set, which is highly flexible. In other embodiments, the number and resistance of the sampling resistors of the sampling module 51 can be adjusted according to actual needs.

[0037] Preferably, the constant current driving chip U1 has a built-in switch-controlled MOS tube, which can control the energy storage inductor to store and discharge energy and provide energy to the load by turning the built-in MOS tube on and off.

[0038] It should be noted that the model of the constant current driver chip U1 is preferably BP2861, but it is not limited to this and can be adjusted according to actual needs.

[0039] 4. Output circuit 6

[0040] The output circuit 6 includes a third electrolytic capacitor EC3 and a third resistor R2; the positive terminal of the third electrolytic capacitor is respectively connected to the first filter circuit 4, the power supply pin HV and the first connection pad C1 (such as the LED+ terminal), the negative terminal of the third electrolytic capacitor is respectively connected to the second inductor, the second filter circuit 52 and the second connection pad D1 (such as the LED- terminal), and the third electrolytic capacitor EC3 is connected in parallel with the third resistor R2. The output circuit 6 is set to provide stable direct current to the light source circuit 7, thereby improving the stability of lighting work.

[0041] It should be noted that the light source circuit 7 includes a plurality of LED lamps.

[0042] Preferably, the utility model further provides a lighting fixture, comprising a lamp body, a lighting circuit board and the above-mentioned switching power supply device, wherein the switching power supply device and the lighting circuit board are packaged in the lamp body. Since the above-mentioned switching power supply device has the above-mentioned technical effects, the lighting fixture including the above-mentioned switching power supply device should also have the above-mentioned technical effects, which will not be described in detail here.

[0043] The above is a preferred embodiment of the present utility model. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present utility model.

Claims

1. A switching power supply device, characterized in that: It includes a power supply board, which is welded on the lighting circuit board through a welding pad and is electrically connected to the lighting circuit board; The power board is provided with a rectifier circuit, a first filter circuit, a constant current drive circuit and an output circuit; The rectifier circuit is connected to the constant current drive circuit and the output circuit respectively through the first filter circuit, and is used to convert the external input alternating current into direct current, and supply power to the constant current drive circuit and the output circuit after filtering; The constant current driving circuit is connected to the light source circuit on the lighting circuit board through the output circuit, and is used to drive the light source circuit to operate at a constant current.

2. The switching power supply device according to claim 1, characterized in that: The power board is provided with at least a power live wire pad, a power neutral wire pad, a first connection pad and a second connection pad, and the lighting circuit board is provided with mounting pads which are welded and connected to the power live wire pad, the power neutral wire pad, the first connection pad and the second connection pad in a one-to-one correspondence; The power live wire pad and the power neutral wire pad are respectively connected to the rectifier circuit and are respectively welded to corresponding terminals of an external AC power source; The first connection pad and the second connection pad are respectively connected to the output circuit and are respectively connected to the light source circuit through mounting pads.

3. The switching power supply device according to claim 2, characterized in that: The rectifier circuit includes a fuse resistor, a varistor and a rectifier bridge; The first AC input terminal of the rectifier bridge is connected to the live wire pad of the power supply through the fuse resistor, and the second AC input terminal of the rectifier bridge is connected to the neutral wire pad of the power supply; The first DC output terminal of the rectifier bridge is connected to the first filter circuit and grounded through the varistor, the second DC output terminal of the rectifier bridge is grounded, and the varistor is connected in parallel with the first filter circuit.

4. The switching power supply device according to any one of claims 1 to 3, characterized in that: The first filter circuit includes a first inductor, a first resistor, a first electrolytic capacitor and a second electrolytic capacitor; One end of the first inductor is respectively connected to the output end of the rectifier circuit, one end of the first resistor and the positive terminal of the first electrolytic capacitor, and the other end of the first inductor is respectively connected to the other end of the first resistor, the positive terminal of the second electrolytic capacitor, the constant current drive circuit and the output circuit; The negative terminal of the first electrolytic capacitor is connected to the negative terminal of the second electrolytic capacitor and is grounded.

5. The switching power supply device according to any one of claims 1 to 3, characterized in that: The constant current driving circuit includes a second inductor, a sampling module, a first capacitor, a second filtering circuit and a constant current driving chip, and the constant current driving chip includes a power supply pin, an output pin, a sampling pin and a ground pin; The power supply pin is connected to the first filter circuit and the output circuit respectively, the output pin is connected to the output circuit and the second filter circuit respectively through the second inductor, the sampling pin is connected to the output pin through the first capacitor and grounded through the sampling module, and the grounding pin is grounded.

6. The switching power supply device according to claim 5, characterized in that: The second filtering circuit includes a second resistor and a second capacitor; One end of the second resistor is connected to the second inductor and the output circuit respectively, and the other end of the second resistor is grounded via the second capacitor.

7. The switching power supply device according to claim 5, characterized in that: The sampling module includes at least one sampling resistor.

8. The switching power supply device according to claim 5, characterized in that: The output circuit includes a third electrolytic capacitor and a third resistor; The positive terminal of the third electrolytic capacitor is respectively connected to the first filter circuit, the power supply pin and the first connection pad, the negative terminal of the third electrolytic capacitor is respectively connected to the second inductor, the second filter circuit and the second connection pad, and the third electrolytic capacitor is connected in parallel with the third resistor.

9. The switching power supply device according to claim 2, characterized in that: The power live wire pad and the power neutral wire pad are both arranged at one end of the power board, and the first connecting pad and the second connecting pad are both arranged at the other end of the power board.

10. A lighting fixture, characterized in that: The invention comprises a lamp body, a lighting circuit board and a switching power supply device according to any one of claims 1 to 9, wherein the switching power supply device and the lighting circuit board are packaged in the lamp body.

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