Vehicle-mounted Ethernet surge protection circuit

Abstract

The utility model discloses a vehicle-mounted Ethernet surge protection circuit, which comprises a PHY chip U1, a network transformer chip U2 and a network port socket J1, a surge protection device E1 is connected between the signal input end of the PHY chip U1 and the output end of the network transformer chip U2, the surge protection device E1 comprises a TVS tube D24 and a TVS tube D25, and the TVS tube D24 and the TVS tube D25 are connected with the network port socket J1. The TVS tube D24 and the TVS tube D25 are connected in series between the signal input end of the PHY chip U1 and the output end of the network transformer chip U2, and a surge protection device E2 is arranged between the signal input end of the network transformer chip U2 and the network port socket J1. And the device is prevented from being damaged by instant overvoltage.

Description

Technical Field

[0001] The utility model relates to the technical field of circuit protection, in particular to a vehicle-mounted Ethernet surge protection circuit. Background Art

[0002] Standard Ethernet has proven itself as a secure transmission medium capable of handling large amounts of data in internet infrastructure enterprises, high-speed data centers, and offices and homes. Ethernet offers advantages such as multi-point connectivity, greater bandwidth, and low latency. As more sensors, controllers, and interfaces utilize ever-increasing bandwidth, equipping them with networks that deliver faster data throughput and higher reliability is becoming a trend. Automotive Ethernet transcends the limitations of traditional automotive serial buses, offering more advanced features to meet the bandwidth, data rate, and data security requirements of in-vehicle communications. The complex environment in vehicles, coupled with the need for reliable signal transmission, creates an increasingly urgent need to improve the transmission quality and interference immunity of Ethernet signals. Utility Model Content

[0003] The purpose of the utility model is to overcome the shortcomings and deficiencies of the prior art and to provide a vehicle-mounted Ethernet surge protection circuit.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: an in-vehicle Ethernet surge protection circuit, comprising a PHY chip U1, a network transformer chip U2, and a network port socket J1; a surge protection device E1 is connected between the signal input end of the PHY chip U1 and the output end of the network transformer chip U2; the surge protection device E1 comprises a TVS tube D24 and a TVS tube D25; the TVS tube D24 and the TVS tube D25 are connected in series between the signal input end of the PHY chip U1 and the output end of the network transformer chip U2; a surge protection device E2 is provided between the signal input end of the network transformer chip U2 and the network port socket J1.

[0005] As a preferred technical solution of the present utility model, the surge protection device E2 includes a gas discharge tube GDT1, a gas discharge tube GDT2, a gas discharge tube GDT3 and a gas discharge tube GDT4, one end of the gas discharge tube GDT1 is connected to the 24th pin of the network transformer chip U2, and the other end of the gas discharge tube GDT1 is grounded, one end of the gas discharge tube GDT2 is connected to the 15th pin of the network transformer chip U2, and the other end of the gas discharge tube GDT2 is grounded, one end of the gas discharge tube GDT3 is connected to the 18th pin of the network transformer chip U2, and the other end of the gas discharge tube GDT3 is grounded, one end of the gas discharge tube GDT4 is connected to the 21st pin of the network transformer chip U2, and the other end of the gas discharge tube GDT4 is grounded.

[0006] As an optimal technical solution of the present utility model, the 24th, 15th, 18th and 21st pins of the network transformer chip U2 are respectively connected to resistors R671, R672, R673 and R674, and the resistors R671, R672, R673 and R674 are grounded through capacitor C369.

[0007] As an optimal technical solution of the present invention, a current limiting resistor is connected between the signal input end of the PHY chip U1 and the output end of the network transformer chip U2, and the surge protection device E1 is connected between the current limiting resistor and the signal output end of the network transformer chip U2.

[0008] As a preferred technical solution of the present invention, two groups of current limiting resistors are provided, one group of current limiting resistors includes resistors R663, R664, R665 and R666 connected between the TVS tube D24 and the PHY chip U1, and the other group of current limiting resistors includes resistors R667, R668, R669 and R670 connected between the TVS tube D25 and the PHY chip U1.

[0009] As a preferred technical solution of the present invention, a capacitor group is further provided between the surge protection device E1 and the output end of the network transformer chip U2, and the capacitor group includes capacitor C365, capacitor C366, capacitor C367 and capacitor C368.

[0010] In summary, the beneficial effects of the present invention are:

[0011] 1. Based on the Bob Smith circuit, surge protection and anti-interference measures are implemented at both the input and output ends of the in-vehicle Ethernet signal. The surge protection device E1 uses a TVS tube to protect electronic components and absorb spike pulses. The surge protection device E2 uses a gas discharge tube to protect electronic components and absorb spike pulses, thereby enhancing the surge protection and anti-interference capabilities of the in-vehicle Ethernet transmission circuit.

[0012] 2. The Ethernet surge protection circuit of the present application includes a PHY chip U1, a current limiting resistor, a surge protection device E1, a surge protection device E2, a network transformer chip U2, and a network port socket J1. The current limiting resistor protects the PHY chip U1, and the surge protection devices E1 and E2 can eliminate the differential mode and common mode residual voltages to prevent instantaneous overvoltage from damaging the device. The network transformer chip U2 plays the role of signal coupling to increase the transmission distance and reduce signal interference. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a circuit diagram of the utility model's vehicle-mounted Ethernet surge protection circuit;

[0014] Figure 2 yes Figure 1 Schematic diagram of the lower part of the Ethernet surge protection circuit;

[0015] Figure 3 yes Figure 1 Schematic diagram of the upper part of the Ethernet surge protection circuit;

[0016] Figure 4 This is a schematic diagram of the module structure of the vehicle-mounted Ethernet surge protection circuit of the utility model. DETAILED DESCRIPTION

[0017] In order to make the technical means, creative features, objectives and effects achieved by the present invention easier to understand, the present invention is further described below in conjunction with specific embodiments and drawings. However, the following embodiments are only preferred embodiments of the present invention and are not exhaustive. Based on the embodiments in the implementation manner, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention.

[0018] The specific embodiments of the present utility model are described below with reference to the accompanying drawings.

[0019] like Figures 1 to 4 The illustrated in-vehicle Ethernet surge protection circuit includes a PHY chip U1, a network transformer chip U2, and a network port socket J1. A surge protection device E1 is connected between the signal input end of the PHY chip U1 and the output end of the network transformer chip U2. The surge protection device E1 includes a TVS tube D24 and a TVS tube D25. The TVS tube D24 and the TVS tube D25 are connected in series between the signal input end of the PHY chip U1 and the output end of the network transformer chip U2. A surge protection device E2 is provided between the signal input end of the network transformer chip U2 and the network port socket J1.

[0020] Based on the Bob Smith circuit, surge protection and anti-interference measures are implemented at both the input and output ends of the in-vehicle Ethernet signal. The surge protection device E1 uses a TVS tube to protect electronic components and absorb spike pulses. The surge protection device E2 is preferably a ceramic gas discharge tube to protect electronic components and absorb spike pulses, thereby enhancing the surge protection and anti-interference capabilities of the in-vehicle Ethernet transmission circuit.

[0021] The Ethernet surge protection circuit of the present application includes a PHY chip U1, a current limiting resistor, a surge protection device E1, a surge protection device E2, a network transformer chip U2, and a network port socket J1. The current limiting resistor protects the PHY chip U1, and the surge protection devices E1 and E2 can eliminate the differential mode and common mode residual voltages to prevent instantaneous overvoltage from damaging the device. The network transformer chip U2 plays the role of signal coupling to increase the transmission distance and reduce signal interference.

[0022] The surge protection device E2 includes a gas discharge tube GDT1, a gas discharge tube GDT2, a gas discharge tube GDT3 and a gas discharge tube GDT4. One end of the gas discharge tube GDT1 is connected to the 24th pin of the network transformer chip U2, and the other end of the gas discharge tube GDT1 is grounded. One end of the gas discharge tube GDT2 is connected to the 15th pin of the network transformer chip U2, and the other end of the gas discharge tube GDT2 is grounded. One end of the gas discharge tube GDT3 is connected to the 18th pin of the network transformer chip U2, and the other end of the gas discharge tube GDT3 is grounded. One end of the gas discharge tube GDT4 is connected to the 21st pin of the network transformer chip U2, and the other end of the gas discharge tube GDT4 is grounded.

[0023] Pins 24, 15, 18, and 21 of the network transformer chip U2 are connected to resistors R671, R672, R673, and R674, respectively. The resistors R671, R672, R673, and R674 are grounded via a capacitor C369.

[0024] A current limiting resistor is connected between the signal input end of the PHY chip U1 and the output end of the network transformer chip U2 , and the surge protection device E1 is connected between the current limiting resistor and the signal output end of the network transformer chip U2 .

[0025] There are two groups of current limiting resistors, one of which includes resistors R663, R664, R665 and R666 connected between the TVS tube D24 and the PHY chip U1, and the other group of current limiting resistors includes resistors R667, R668, R669 and R670 connected between the TVS tube D25 and the PHY chip U1.

[0026] A capacitor group connected between the surge protection device E1 and the output end of the network transformer chip U2 is also provided. The capacitor group includes a capacitor C365, a capacitor C366, a capacitor C367 and a capacitor C368.

[0027] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only preferred examples of the present invention and are not intended to limit the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and improvements fall within the scope of the present invention as claimed, and the scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. An in-vehicle Ethernet surge protection circuit, comprising a PHY chip U1, a network transformer chip U2, and a network port socket J1, characterized in that: A surge protection device E1 is connected between the signal input end of the PHY chip U1 and the output end of the network transformer chip U2. The surge protection device E1 includes a TVS tube D24 and a TVS tube D25. The TVS tube D24 and the TVS tube D25 are connected in series between the signal input end of the PHY chip U1 and the output end of the network transformer chip U2. A surge protection device E2 is provided between the signal input end of the network transformer chip U2 and the network port socket J1.

2. The in-vehicle Ethernet surge protection circuit according to claim 1, characterized in that: The surge protection device E2 includes a gas discharge tube GDT1, a gas discharge tube GDT2, a gas discharge tube GDT3 and a gas discharge tube GDT4. One end of the gas discharge tube GDT1 is connected to the 24th pin of the network transformer chip U2, and the other end of the gas discharge tube GDT1 is grounded. One end of the gas discharge tube GDT2 is connected to the 15th pin of the network transformer chip U2, and the other end of the gas discharge tube GDT2 is grounded. One end of the gas discharge tube GDT3 is connected to the 18th pin of the network transformer chip U2, and the other end of the gas discharge tube GDT3 is grounded. One end of the gas discharge tube GDT4 is connected to the 21st pin of the network transformer chip U2, and the other end of the gas discharge tube GDT4 is grounded.

3. The in-vehicle Ethernet surge protection circuit according to claim 1 or 2, characterized in that: Pins 24, 15, 18 and 21 of the network transformer chip U2 are connected to resistors R671, R672, R673 and R674 respectively, and the resistors R671, R672, R673 and R674 are grounded via capacitor C369.

4. The in-vehicle Ethernet surge protection circuit according to claim 1, characterized in that: A current limiting resistor is connected between the signal input end of the PHY chip U1 and the output end of the network transformer chip U2 , and the surge protection device E1 is connected between the current limiting resistor and the signal output end of the network transformer chip U2 .

5. The in-vehicle Ethernet surge protection circuit according to claim 4, characterized in that: There are two groups of current limiting resistors, one of which includes resistors R663, R664, R665 and R666 connected between the TVS tube D24 and the PHY chip U1, and the other group of current limiting resistors includes resistors R667, R668, R669 and R670 connected between the TVS tube D25 and the PHY chip U1.

6. The in-vehicle Ethernet surge protection circuit according to claim 1, characterized in that: A capacitor group connected between the surge protection device E1 and the output end of the network transformer chip U2 is also provided. The capacitor group includes a capacitor C365, a capacitor C366, a capacitor C367 and a capacitor C368.

Images