Internet port differential mode 10KV lightning protection circuit

Abstract

The utility model relates to the technical field of switches, in particular to a network port differential mode 10KV lightning protection circuit, which comprises a primary lightning protection module and a secondary lightning protection module, the primary lightning protection module comprises a diode D3, a diode D4 and a diode D5, and the secondary lightning protection module comprises a diode D1 and a diode D2. The positive electrode of the POE power supply device is connected with a diode D4, and the negative electrode of the POE power supply device is connected with a diode D3, so that a backflow path of lightning stroke energy is formed; and then another lightning stroke energy backflow path of the POE power supply device is formed through the diode D5, so that the lightning protection effect can be well realized, the secondary lightning protection module protects the PSE device through the two diodes, and the design cost and the use cost can be greatly reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of switches, in particular to a differential-mode 10KV lightning protection circuit for network ports. Background Art

[0002] In recent years, with the rapid expansion of network infrastructure, Power over Ethernet (POE) technology has been widely adopted in many application scenarios due to its convenience and flexibility, especially in outdoor or harsh weather environments such as security monitoring, wireless access points, and IP telephones. POE switches, as the core components of POE technology, undertake the dual tasks of power supply and data transmission for terminal devices, and their stability and reliability directly affect the performance of the entire network system.

[0003] However, for POE switches deployed outdoors or in areas with frequent lightning activities, lightning strikes pose a serious threat. The instantaneous high-voltage pulses generated by lightning can invade the device along the power line, signal line, or antenna feeder, resulting in overvoltage and overcurrent, thereby damaging sensitive electronic components or even the entire system. Therefore, the lightning protection of POE switches has become a key element that cannot be ignored in the design.

[0004] Currently in the market, the lightning protection level standard for the network ports of most POE switches is 6kV (kilovolts) for common-mode protection and 4kV for differential-mode protection. This level is sufficient to provide basic protection in a conventional environment. However, in areas with frequent lightning or other extreme conditions, this protection level often proves inadequate. When lightning directly or indirectly strikes the network line, higher-energy surges may easily penetrate the above protection measures and cause a fatal blow to the POE circuit.

[0005] Although there are higher-level lightning protection solutions, such as using high-performance Transient Voltage Suppressor (TVS) diodes to enhance the lightning protection effect, the cost issue of such solutions cannot be underestimated. As the core component in the lightning protection circuit, the power capacity, package form, and price of TVS diodes are directly related to the level of lightning protection. Higher-specification TVS diodes mean higher costs. Another example is the lightning protection circuit disclosed in Patent 200920209547.7, which has a multi-stage lightning protection structure, but with more components, the cost is relatively higher. This not only increases the manufacturing cost of POE switches but also directly raises the procurement and maintenance costs for users, becoming a major obstacle to large-scale deployment and application.

[0006] In view of this, finding a solution that can effectively improve the lightning protection ability of POE switches while controlling costs has become an urgent need in the industry. Summary of the Invention

[0007] The utility model provides a differential mode 10KV lightning protection circuit for network ports aiming at the problems of the prior art, which can achieve the lightning protection effect of POE with low cost.

[0008] In order to solve the above technical problems, the utility model adopts the following technical scheme: a differential mode 10KV lightning protection circuit for network ports, which includes a primary lightning protection module and a secondary lightning protection module. The primary lightning protection module includes diode D3, diode D4 and diode D5, and the secondary lightning protection module includes diode D1 and diode D2. The positive pole of the POE power supply device is grounded through diode D4, the negative pole of the POE power supply is grounded through diode D3, the positive pole of the POE power supply device is connected to the negative pole of the POE power supply device through diode D5, the external PSE device is connected to the positive pole of the POE power supply device through diode D2, and the external PSE device is connected to the negative pole of the POE power supply device through diode D1.

[0009] Preferably, the diode D1 is a Schottky diode.

[0010] Preferably, the diode D2 is a Schottky diode.

[0011] Preferably, the diode D3 is a Schottky diode.

[0012] Preferably, the diode D4 is a high-power TVS tube.

[0013] Preferably, the diode D5 is a Schottky diode.

[0014] The beneficial effects of the utility model are as follows:

[0015] 1. The design cost is low. A diode D4 is connected to the positive pole of the POE power supply device, and a diode D3 is connected to the negative pole of the POE power supply device, thereby forming a return path for lightning strike energy. Another return path for lightning strike energy of the POE power supply device is formed through diode D5, so that the lightning protection effect can be well achieved. The secondary lightning protection module protects the PSE device through two diodes, which can greatly reduce the design cost and use cost.

[0016] 2. The design is simple and reliable, which greatly shortens the design time, is easy to troubleshoot faults, has low maintenance cost, and makes the quality more reliable. Description of the Drawings

[0017] Figure 1 is the circuit schematic diagram of the utility model. Detailed Embodiments

[0018] For the convenience of those skilled in the art, the present utility model will be further described below in conjunction with embodiments and drawings. The content mentioned in the embodiments does not limit the present utility model. The present utility model will be described in detail below with reference to the drawings.

[0019] A 10KV common mode lightning protection circuit for network ports provided in this embodiment is as Figure 1 , this embodiment sets up a two-stage lightning protection function, including a primary lightning protection module and a secondary lightning protection module. The primary lightning protection module includes diodes D3, D4, and D5, and the secondary lightning protection module includes diodes D1 and D2; the positive pole of the POE power supply device is grounded through diode D4, the negative pole of the POE power supply device is grounded through diode D3, the positive pole of the POE power supply device is connected to the negative pole of the POE power supply device through diode D5, the external PSE device is connected to the positive pole of the POE power supply device through diode D2, and the external PSE device is connected to the negative pole of the POE power supply device through diode D1. Among them, the anode of diode D1 is connected to the negative pole of the POE power supply, and the cathode of diode D1 is connected to the PSE device; the anode of diode D2 is connected to the positive pole of the POE power supply, and the cathode of diode D2 is connected to the PSE device; the anode of diode D3 is grounded, and the cathode of diode D3 is connected to the negative pole of the POE power supply; the anode of diode D4 is grounded, and the cathode of diode D4 is connected to the positive pole of the POE power supply; the anode of diode D5 is connected to the negative pole of the POE power supply, and the cathode of diode D5 is connected to the positive pole of the POE power supply.

[0020] Furthermore, diodes D1, D2, D3, and D5 are Schottky diodes, and diode D4 is a high-power TVS tube.

[0021] Specifically, the main path of the common mode lightning strike on the network port is line-to-line, which means that lightning strike energy is applied from the positive pole of the POE power supply to the negative pole of the POE power supply. Whether it is positive to negative or negative to positive, when the POE switch is in normal use, the lightning strike energy enters from the network cable, then reaches the RJ45 of the POE switch, and then reaches the inside of the POE switch through the POE power supply line sequence. The lightning protection principle of this embodiment is as follows (hereinafter, the positive pole of the network port power supply line sequence 1 / 2 line sequence (12+), and the negative pole of the 3 / 6 line sequence (36-) are used as an example for elaboration):

[0022] 1. When lightning strike energy enters from the positive pole (12+) of the POE power supply device and the negative pole (36-) forms a loop, the first-stage lightning protection module comes into play. First, a high-power TVS diode D4 discharges the energy of the positive pole (12+) to the ground of the POE power supply device. Then, through a Schottky diode D3 (M7), from the ground of the POE power supply device to the negative pole (36-) of the network port. At this time, the lightning strike energy has a return path, which is from the network cable 12+ to the diode D4, then to the ground of the POE power supply device, then to the diode D3, and finally to the 36- of the network cable;

[0023] 2. When lightning strike energy enters from the negative pole (36-) of the POE power supply device and the positive pole (12+) forms a loop, the energy on the network cable sequence 36- is directly discharged to the POE positive pole (12+) through a Schottky diode D5 (M7). At this time, the lightning strike energy has a return path, that is, from the network cable sequence 36- to the diode D5, and then to the network cable sequence 12+;

[0024] 3. The second-stage lightning protection module mainly protects the PSE chip when the lightning strike residual voltage is too high. For example, when the lightning strike energy of the positive pole is very large but cannot be completely and quickly released, the PSE chip is also one of its discharge paths. However, by connecting two Schottky diodes (M7) D1 and D2 to the positive and negative poles of the PSE chip at the same time, it can effectively prevent the lightning strike energy from passing through the PSE chip (M7 blocks the lightning strike path of the PSE chip), which well protects the PSE chip. This is the function of the second-stage lightning protection design; (The Schottky diode is M7, 1000V / 1A).

[0025] Therefore, this embodiment can achieve a low-cost and effective lightning protection effect: 1. Low design cost. Only a TVS tube needs to be placed at the positive pole of the POE power supply. The lightning protection discharge path of the POE negative pole is entirely replaced by Schottky diodes (M7). The unit price cost of Schottky diodes is much lower than that of TVS diodes, which greatly reduces the design cost and usage cost; 2. High lightning protection level. Since the reverse voltage withstand of the Schottky diode M7 can reach 1000V and the overcurrent capacity can reach 1A, this design method will greatly improve the lightning protection level; 3. Simple and reliable design. It greatly shortens the design time, is easy to troubleshoot faults, has a low maintenance cost, and makes the quality more reliable.

[0026] The above are only the preferred embodiments of the present utility model, and do not impose any form of limitation on the present utility model. Although the present utility model is disclosed above in the preferred embodiments, it is not intended to limit the present utility model. Any person skilled in the art, without departing from the scope of the technical solution of the present utility model, when making some changes or modifications using the above-disclosed technical content into equivalent embodiments of equivalent changes, but as long as it does not depart from the content of the technical solution of the present utility model, any simple modification, equivalent change and modification made to the above embodiments according to the technology of the present utility model shall fall within the scope of the technical solution of the present utility model.

Claims

1. A network port differential mode 10KV lightning protection circuit, characterized in that: It includes a primary lightning protection module and a secondary lightning protection module, the primary lightning protection module includes a diode D3, a diode D4 and a diode D5, and the secondary lightning protection module includes a diode D1 and a diode D2; the positive electrode of the POE power supply device is grounded through the diode D4, the negative electrode of the POE power supply is grounded through the diode D3, the positive electrode of the POE power supply device is connected to the negative electrode of the POE power supply device through the diode D5, the external PSE device is connected to the positive electrode of the POE power supply device through the diode D2, and the external PSE device is connected to the negative electrode of the POE power supply device through the diode D1.

2. According to claim 1, a network port differential mode 10KV lightning protection circuit is characterized in that: The diode D1 is a Schottky diode.

3. According to claim 1, a network port differential mode 10KV lightning protection circuit is characterized in that: The diode D2 is a Schottky diode.

4. According to claim 1, a network port differential mode 10KV lightning protection circuit is characterized in that: The diode D3 is a Schottky diode.

5. According to claim 1, a network port differential mode 10KV lightning protection circuit is characterized in that: The diode D4 is a high-power TVS tube.

6. According to claim 1, a network port differential mode 10KV lightning protection circuit is characterized in that: The diode D5 is a Schottky diode.

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