External protection circuit for inhibiting common-mode network port lightning stroke and power supply equipment

Abstract

The utility model provides an external protection circuit for inhibiting common mode network port lightning stroke and a power supply device. The external protection circuit comprises a first magnetic bead, a second magnetic bead, a capacitor and a bidirectional TVS tube. One end of the first magnetic bead is connected with a positive electrode of a power supply output end, and the other end of the first magnetic bead is divided into three paths, one path is connected with one end of the capacitor, one path is connected with one end of the bidirectional TVS tube, and one path is connected with a positive electrode input end of terminal equipment; one end of the second magnetic bead is connected with the negative electrode of the power supply output end, the other end of the second magnetic bead is divided into three paths, one path is connected with the other end of the capacitor, one path is connected with the other end of the bidirectional TVS tube, and one path is connected with the negative electrode input end of the terminal equipment. The external protection circuit is connected between the output end of the power supply and the terminal equipment, so that pulse energy and peak interference are inhibited and absorbed at the front end of the terminal equipment, a common-mode network port of the terminal equipment is prevented from being impacted by transient high energy, and the terminal equipment is protected.

Description

Technical Field

[0001] The utility model relates to the technical field of power supply circuits, and in particular to an external protection circuit and a power supply device for suppressing lightning strikes on common-mode network ports. Background Art

[0002] In the network port lightning test under the whole machine test, the existing power supply products are subject to high-frequency pulse and spike interference, which will cause the terminal equipment to lose power and flicker, resulting in abnormal product use. This is mostly due to the space and solution limitations of the product, which cannot achieve the maximum strength of anti-common mode lightning protection for the network port. Utility Model Content

[0003] The technical problem to be solved by the utility model is to provide an external protection circuit and power supply equipment for suppressing lightning strikes on common-mode network ports, which can effectively protect the common-mode network ports of terminal devices from being affected by lightning strikes, and fundamentally solve the problems of power failure and screen flashing caused by lightning strikes on terminal devices.

[0004] In order to solve the above technical problems, the first technical solution adopted by the utility model is:

[0005] An external protection circuit for suppressing common-mode network port lightning strikes includes a first magnetic bead, a second magnetic bead, a capacitor and a bidirectional TVS tube; one end of the first magnetic bead is connected to the positive pole of a power output terminal, and the other end of the first magnetic bead is divided into three paths, one path is connected to one end of the capacitor, one path is connected to one end of the bidirectional TVS tube, and one path is connected to the positive input terminal of a terminal device; one end of the second magnetic bead is connected to the negative pole of the power output terminal, and the other end of the second magnetic bead is divided into three paths, one path is connected to the other end of the capacitor, one path is connected to the other end of the bidirectional TVS tube, and one path is connected to the negative input terminal of the terminal device.

[0006] In some embodiments, the first magnetic beads are composed of magnetic beads L1 and magnetic beads L3 connected in parallel; the second magnetic beads are composed of magnetic beads L2 and magnetic beads L4 connected in parallel.

[0007] In some embodiments, the magnetic beads L1, L3, L2 and L4 are all patch magnetic beads.

[0008] In some embodiments, the parameters of the magnetic bead L1, magnetic bead L3, magnetic bead L2 or magnetic bead L4 are 330Ω / 100MHz; the dissipation power of the bidirectional TVS tube is 400W, and the cut-off voltage is 58V.

[0009] In some embodiments, the capacitor is a chip capacitor.

[0010] In some embodiments, the bidirectional TVS tube is a patch bidirectional TVS tube.

[0011] The second technical solution adopted by the utility model is:

[0012] A power supply device includes a power supply circuit and a terminal device, and also includes an external protection circuit for suppressing common-mode network port lightning strikes as described above; one end of the external protection circuit is connected to the output end of the power supply circuit, and the other end is connected to the output end of the terminal device.

[0013] In some embodiments, the power supply circuit includes an AC input, a rectifier and filter circuit, a transformer, a main control circuit, an output filter circuit, a feedback circuit, and an output terminal connected in sequence.

[0014] The beneficial effect of the utility model is that the utility model connects an external protection circuit between the power output end and the terminal device to prevent the common mode network port of the terminal device from being impacted by transient high energy by suppressing and absorbing pulse energy and peak interference at the front end of the terminal device, thereby protecting the terminal device and fundamentally solving the problem of power failure and screen flashing caused by surge lightning strikes on the terminal device, thereby greatly improving the service life of the terminal device. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic diagram of the structure and connection of an external protection circuit for suppressing common-mode network port lightning strikes provided by an embodiment of the utility model;

[0016] Figure 2 A schematic diagram of the internal structure of an external protection circuit for suppressing common-mode network port lightning strikes provided in a specific embodiment of the utility model;

[0017] Figure 3 A schematic diagram of the frame structure connection of a power supply device provided by an embodiment of the utility model;

[0018] Figure 4 A connection diagram of a power supply device provided for a specific implementation of the utility model.

[0019] Description of labels:

[0020] 10. Power supply circuit; 20. External protection circuit; 30. Terminal equipment;

[0021] 21. first magnetic bead; 22. second magnetic bead;

[0022] 11. AC input; 12. Rectification and filtering circuit; 13. Transformer; 14. Main control circuit; 15. Output filtering circuit; 16. Feedback circuit; 17. Output end. DETAILED DESCRIPTION

[0023] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in conjunction with the implementation modes and the accompanying drawings.

[0024] The key concept of the utility model is to connect an external protection circuit between the power output end and the terminal device to prevent the common mode network port of the terminal device from being impacted by transient high energy by suppressing and absorbing pulse energy and spike interference at the front end of the terminal device.

[0025] Please refer to Figure 1 , Embodiment 1 of the present utility model is:

[0026] The present embodiment provides an external protection circuit 20 for suppressing common-mode network port lightning strikes, including a first magnetic bead 21, a second magnetic bead 22, a capacitor CA and a bidirectional TVS tube D7; one end of the first magnetic bead 21 is connected to the positive output terminal of the power supply circuit 10, and the other end of the first magnetic bead 21 is divided into three paths, one path is connected to one end of the capacitor CA, one path is connected to one end of the bidirectional TVS tube D7, and one path is connected to the positive input terminal of the terminal device 30; one end of the second magnetic bead 22 is connected to the negative output terminal of the power supply circuit 10, and the other end of the second magnetic bead 22 is divided into three paths, one path is connected to the other end of the capacitor CA, one path is connected to the other end of the bidirectional TVS tube D7, and one path is connected to the negative input terminal of the terminal device 30.

[0027] In this embodiment, the above-mentioned external protection circuit is connected between the power output end and the terminal device, so that the external protection circuit at the front end of the terminal device prevents the common mode network port of the terminal device from being impacted by transient high energy by suppressing and absorbing pulse energy and spike interference; thereby protecting the terminal device and fundamentally solving the problem of power failure and screen flashing caused by surge lightning strikes on the terminal device; thereby greatly improving the service life of the terminal device.

[0028] In this embodiment, the external protection circuit is mainly composed of a first magnetic bead, a second magnetic bead, a capacitor and a bidirectional TVS tube. Specifically, the first magnetic bead and the second magnetic bead are used to suppress high-frequency noise and spike interference on the signal line and the power line, and have a strong ability to absorb electrostatic pulses; the capacitor is used to remove clutter or low-frequency noise in the circuit. When clutter or noise enters the circuit, the charge stored in the capacitor can eliminate these interference signals, thereby preventing clutter or noise from affecting the normal operation of the circuit; the bidirectional TVS tube is used to reduce its impedance suddenly at a very high speed (up to 1*10^-12 seconds) when both ends of the TVS tube are subjected to a momentary high-energy impact, and can also absorb a large current and clamp the voltage between its two ends to a predetermined value, thereby ensuring that the components in the terminal equipment connected thereafter are protected from damage by transient high-energy impacts, and can prevent up to 8KV surges.

[0029] In some specific embodiments, Figure 2As shown, the first magnetic bead is composed of magnetic beads L1 and L3 connected in parallel; the second magnetic bead is composed of magnetic beads L2 and L4 connected in parallel. Here, the magnetic beads connected in parallel can effectively reduce the loss of the circuit and improve the working efficiency of the circuit; at the same time, the power requirements are met.

[0030] Optionally, the parameters of magnetic bead L3, magnetic bead L2 or magnetic bead L4 are 330Ω / 100MHz. Optionally, the dissipation power of the bidirectional TVS tube is 400W, and the cutoff voltage is 58V. The selection of the above parameters will optimize the circuit performance and improve the lightning protection effect.

[0031] In some specific embodiments, the magnetic beads L1, L3, L2 and L4 are all SMD magnetic beads. Accordingly, the capacitor is a SMD capacitor; and the bidirectional TVS tube is a SMD bidirectional TVS tube. Here, the components in the external protection circuit are all SMD components, which can greatly reduce the size of the external protection circuit and make the circuit structure simpler.

[0032] The external protection circuit provided in this embodiment also has the characteristics of simple structure, small size, stable performance, and low cost.

[0033] Please refer to Figure 3 and Figure 4 , Embodiment 2 of the present utility model is:

[0034] This embodiment provides a power supply device, such as Figure 3 As shown, it includes a power supply circuit 10 and a terminal device 30, and also includes the external protection circuit 20 for suppressing common-mode network port lightning strike as described in the above embodiment; one end of the external protection circuit 20 is connected to the output end of the power supply circuit 10, and the other end is connected to the input end of the terminal device 30.

[0035] The power supply device provided in this embodiment connects an external protection circuit between the output end of the power supply circuit and the input end of the terminal device, so that the external protection circuit at the front end of the terminal device prevents the common mode network port of the terminal device from being impacted by transient high energy by suppressing and absorbing pulse energy and spike interference; thereby protecting the terminal device and fundamentally solving the problem of power failure and screen flickering caused by surge lightning strikes on the terminal device; thereby greatly improving the service life of the terminal device.

[0036] In this embodiment, the power supply circuit may be a switching power supply circuit or other circuit that provides power; the terminal device may be a set-top box, a switch, a camera or other products.

[0037] In some specific embodiments, Figure 4As shown, the power supply circuit 10 includes an AC input 11, a rectifier filter circuit 12, a transformer 13, a main control circuit 14, an output filter circuit 15, a feedback circuit 16 and an output terminal 17 which are connected in sequence.

[0038] In summary, the external protection circuit and power supply device for suppressing common-mode network port lightning strike provided by the utility model connect an external protection circuit between the power output end and the terminal device to prevent the common-mode network port of the terminal device from being impacted by transient high energy (up to 8KV) by suppressing and absorbing pulse energy and spike interference at the front end of the terminal device, thereby protecting the terminal device and fundamentally solving the problem of power failure and screen flashing caused by surge lightning strikes on the terminal device, thereby greatly improving the service life of the terminal device. At the same time, the external protection circuit also has the characteristics of simple structure, small size, stable performance, low cost, etc., and can be widely used in various electronic terminal product fields.

[0039] The above description is only an embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent transformations made using the contents of the specification and drawings of the present invention, or directly or indirectly applied in the relevant technical field, are also included in the patent protection scope of the present invention.

Claims

1. External protection circuit for suppressing common mode network port lightning strike, characterized by: The invention comprises a first magnetic bead, a second magnetic bead, a capacitor and a bidirectional TVS tube; one end of the first magnetic bead is connected to the positive pole of the power output terminal, and the other end of the first magnetic bead is divided into three paths, one path is connected to one end of the capacitor, one path is connected to one end of the bidirectional TVS tube, and one path is connected to the positive input terminal of the terminal device; one end of the second magnetic bead is connected to the negative pole of the power output terminal, and the other end of the second magnetic bead is divided into three paths, one path is connected to the other end of the capacitor, one path is connected to the other end of the bidirectional TVS tube, and one path is connected to the negative input terminal of the terminal device.

2. The external protection circuit for suppressing common-mode network port lightning strikes according to claim 1, characterized in that: The first magnetic beads are composed of magnetic beads L1 and magnetic beads L3 connected in parallel; the second magnetic beads are composed of magnetic beads L2 and magnetic beads L4 connected in parallel.

3. The external protection circuit for suppressing common-mode network port lightning strikes according to claim 2, characterized in that: The magnetic beads L1, L3, L2 and L4 are all patch magnetic beads.

4. The external protection circuit for suppressing common-mode network port lightning strikes according to claim 2, characterized in that: The parameters of the magnetic bead L1, magnetic bead L3, magnetic bead L2 or magnetic bead L4 are 330Ω / 100MHz; the dissipation power of the bidirectional TVS tube is 400W, and the cutoff voltage is 58V.

5. The external protection circuit for suppressing common-mode network port lightning strikes according to claim 1, characterized in that: The capacitor is a chip capacitor.

6. The external protection circuit for suppressing common-mode network port lightning strikes according to claim 1, characterized in that: The bidirectional TVS tube is a patch bidirectional TVS tube.

7. A power supply device, comprising a power supply circuit and a terminal device, characterized in that: It also includes an external protection circuit for suppressing common-mode network port lightning strikes as described in any one of claims 1 to 6 above; one end of the external protection circuit is connected to the output end of the power supply circuit, and the other end is connected to the output end of the terminal device.

8. A power supply device as claimed in claim 7, characterized in that: The power supply circuit includes an AC input, a rectifier filter circuit, a transformer, a main control circuit, an output filter circuit, a feedback circuit and an output end which are connected in sequence.

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