CN220086955U - Protective device and vehicle - Google Patents

Abstract

The utility model provides a protection device and a vehicle. The protection device comprises a shell and a circuit board, wherein the shell forms an accommodating cavity and is used as a first ground wire to release surge energy; the circuit board is arranged in the accommodating cavity and is provided with a protection circuit; the protection circuit is used for isolating surge energy. The protection device provided by the utility model can reduce damage of surge energy to electronic elements and improve the safety of a vehicle-mounted electronic system.

Description

Protective device and vehicle

Technical Field

The present disclosure relates to electronic technology, and in particular, to a protection device and a vehicle.

Background

Electrical overstress is a common cause of damage to electronic components in the form of a large amount of thermal energy generated by excessive pressure or flow, which causes the internal temperature of the electronic components to be too high, thereby damaging the electronic components. The voltage and current exceeding the stable values, i.e., surge energy, cause the internal temperature of the electronic component to be excessively high, thereby damaging the electronic component.

For example, in the application of new energy automobile charging stations, commercial charging stations are generally built outdoors, and when general users charge, the situation of pulling wires to the outdoors exists, and because of long-distance power supply, particularly when charging outdoors, lightning surge energy is very easy to be introduced into an electric power system. The lightning surge energy belongs to high-energy surge energy, and the surge energy can enter a new energy vehicle along a charging gun through a power supply line, and can cause the charging gun and the like to form serious ground reaction phenomenon to damage electronic elements in the vehicle due to irregular wiring of a power line and poor grounding even without a grounding wire. When lightning surge energy is discharged through the ground wire, the ground level of a signal of the vehicle-mounted charger is raised due to the existence of ground impedance (ground wire impedance, installation contact impedance and the like), so that a ground potential difference is formed between the vehicle-mounted charger and a vehicle body, and a ground potential difference is generated between the vehicle-mounted charger and other electronic systems in the vehicle body, so that a ground loop is formed, and equipment is damaged.

Disclosure of Invention

The utility model provides a protection device and a vehicle, which can reduce damage of surge energy to electronic elements and improve safety of a vehicle-mounted electronic system.

In order to solve the technical problems, the utility model adopts a technical scheme that: the protection device comprises a shell and a circuit board, wherein the shell forms an accommodating cavity and is used as a first ground wire to release surge energy; the circuit board is arranged in the accommodating cavity and is provided with a protection circuit; the protection circuit is used for isolating surge energy.

The protection device comprises a first port and a second port, wherein the first port is arranged at one end of the annular shell; the second port is arranged at the other end of the annular shell; the circuit board is positioned between the first port and the second port, and the first port and the second port are electrically connected with the protection circuit.

The first port and the second port are connected through a signal bus, and the protection circuit is connected between the signal buses of the first port and the second port in series.

The protection circuit at least comprises a first protection circuit and a second protection circuit, wherein the input end of the first protection circuit is connected with the signal bus, the output end of the first protection circuit is connected with the second ground wire, and the first protection circuit is used for absorbing static electricity and surge energy; the second protection circuit is connected in series between the connection point of the first protection circuit and the signal bus and the second port, and the second protection circuit is used for isolating surge energy.

Wherein the signal bus comprises a dominant line and a recessive line; the first protection circuit comprises at least two first protection sub-circuits, wherein the input end of one first protection sub-circuit is connected with a dominant line, and the output end of the first protection sub-circuit is connected with a second ground wire so as to receive static electricity and surge energy of the dominant line; the input end of the other first protection subcircuit is connected with the hidden line, and the output end of the other first protection subcircuit is connected with the second ground wire so as to receive static electricity and surge energy of the hidden line.

The first protection subcircuit comprises any one of a high-power transient suppression diode, a semiconductor discharge tube, a piezoresistor or a gas discharge tube, and any one of the high-power transient suppression diode, the semiconductor discharge tube, the piezoresistor and the gas discharge tube is correspondingly connected in parallel between the dominant line and the second ground line and between the recessive line and the second ground line.

The second protection circuit comprises at least two second protection subcircuits, and one second protection subcircuit is connected in series between the connection point of the first protection subcircuit and the dominant line and the second port so as to isolate surge energy on the dominant line; the other second protection subcircuit is connected in series between the connection point of the other first protection subcircuit and the hidden line and the second port so as to isolate surge energy on the hidden line.

The second protection subcircuit comprises a transient blocking unit and a transient suppression diode, the input end of the transient blocking unit is connected with the connection point of the first protection subcircuit and the dominant line or the recessive line, and the output end of the transient blocking unit is connected with the second port; one end of the transient suppression diode is connected with the input end of the transient blocking unit, and the other end of the transient suppression diode is connected with the output end of the transient blocking unit.

The protection circuit further comprises a third protection circuit, the input end of the third protection circuit is connected with the signal bus between the second protection circuit and the second port, and the output end of the third protection circuit is connected with the second ground wire and used for absorbing static electricity and surge energy.

Wherein the signal bus comprises a dominant line and a recessive line; the third protection circuit comprises at least two third protection subcircuits, the input end of one third protection subcircuit is connected with the dominant line, and the output end of the third protection subcircuit is connected with the second ground line; the input end of the other third protection subcircuit is connected with the recessive line, and the output end of the other third protection subcircuit is connected with the second ground line.

Wherein the third protection subcircuit comprises any one of a low power transient suppression diode, a semiconductor discharge tube, a varistor, or a gas discharge tube, and any one of the low power transient suppression diode, the semiconductor discharge tube, the varistor, and the gas discharge tube is correspondingly connected in parallel between the dominant line and the second ground line, and between the recessive line and the second ground line.

In order to solve the technical problems, the utility model adopts another technical scheme that: there is provided a vehicle comprising the protective device described above.

The beneficial effects of the utility model are as follows: according to the protection device provided by the utility model, the shell and the circuit board are arranged, wherein the circuit board is provided with the protection circuit, and the circuit board is arranged in the accommodating cavity of the shell. By the mode, when the shell is used as the first ground wire, the shell can be used for discharging surge energy; furthermore, the protection circuit is used for isolating surge energy, namely cutting off a signal ground loop and blocking 'ground impact' energy, so that damage of the surge energy to electronic elements is reduced, and the safety of the vehicle-mounted electronic system is improved.

Drawings

For a clearer description of the technical solutions of the embodiments of the present utility model, the drawings that are needed in the description of the embodiments will be briefly introduced below, it being obvious that the drawings in the description below are only some embodiments of the present utility model, and that other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art, wherein:

FIG. 1 is a schematic diagram of a new energy automobile surge energy bleed path;

FIG. 2 is a schematic view of an embodiment of a protection device according to the present utility model;

FIG. 3 is a schematic view of the internal structure of the guard in the embodiment of FIG. 2;

FIG. 4 is a schematic diagram of an embodiment of a protection circuit according to the present utility model;

FIG. 5 is a schematic diagram of an embodiment of the first protection circuit in the embodiment of FIG. 4;

FIG. 6 is a schematic diagram of an embodiment of the first guard sub-circuit in the embodiment of FIG. 5;

FIG. 7 is a schematic diagram of an embodiment of the second protection circuit in the embodiment of FIG. 4;

FIG. 8 is a schematic diagram of an embodiment of a second guard sub-circuit in the embodiment of FIG. 7;

FIG. 9 is a schematic diagram of another embodiment of the second guard sub-circuit in the embodiment of FIG. 7;

FIG. 10 is a schematic diagram of another embodiment of a protection circuit according to the present utility model;

FIG. 11 is a schematic diagram of an embodiment of a third protection circuit in the embodiment of FIG. 10;

FIG. 12 is a schematic diagram of an embodiment of a third guard sub-circuit in the embodiment of FIG. 11;

FIG. 13 is a schematic diagram of a protection circuit according to another embodiment of the present utility model;

fig. 14 is a schematic view of a vehicle according to an embodiment of the present utility model.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

It should be noted that, if directional indications (such as up, down, left, right, front, and rear … …) are included in the embodiments of the present utility model, the directional indications are merely used to explain the relative positional relationship, movement conditions, etc. between the components in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indications are correspondingly changed.

In addition, if there is a description of "first", "second", etc. in the embodiments of the present utility model, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present utility model.

Referring to fig. 1, fig. 1 is a schematic diagram of a surge energy discharging path of a new energy automobile, as shown in fig. 1, a path 1 is a main path of surge energy discharging, surge energy enters a vehicle-mounted charger through a relay of a charging gun along alternating current or alternating current commercial power of a charging station, then enters a shell ground of the vehicle-mounted charger through a third resistor R3 connected with a protection circuit inside the vehicle-mounted charger, finally is discharged to a vehicle body ground through a second resistor R2 connected with the shell ground and the vehicle body ground respectively, and is discharged to a protection conductor (protective earthing conductor) through a first resistor R1 connected with the shell ground and the protection ground respectively, namely a PE wire. Most of the surge energy is discharged after the surge energy passes through the path. The path 2 is a secondary path for discharging surge energy, the surge energy enters a signal circuit of the vehicle-mounted charger through a signal ground of the vehicle-mounted charger, enters other vehicle-mounted electronic systems through a signal line of the signal circuit, and finally is discharged to the vehicle body ground through a fourth resistor R4 respectively connected with the vehicle-mounted electronic systems and the vehicle body ground. But part of the surge energy flows back to the enclosure ground through a second resistor R2 connected to the enclosure ground and the body ground, respectively, and the surge energy may cause damage to signal ports of other electronic systems on the vehicle along the path 2.

The reason for the formation of the path 2 is mainly the sequelae of the path 1: ground impact. When surge energy is discharged through the PE line, the signal ground level of the vehicle-mounted charger is raised due to the existence of ground impedance (ground line impedance, installation contact impedance and the like), so that a ground potential difference (up to hundreds of volts) is formed between the signal ground and a vehicle body, and further, a ground potential difference is generated between the signal ground and other products in the system, so that a ground loop is formed, and equipment is damaged. Especially when the wiring of the charging power line is not standard, the surge energy release loop impedance of the path 1 is larger, the potential difference between the signal ground and the ground of the vehicle body is larger, so that the energy on the path 2 is larger, and equipment damage is very easy to cause.

The utility model provides a protection device which can be applied between signal ports, for example, between a vehicle-mounted electronic system and a vehicle-mounted charger. The protection device can isolate the surge energy of the path 2, reduce the damage of the surge energy to electronic elements and improve the safety of a vehicle-mounted electronic system.

Referring to fig. 2 to 3, fig. 2 is a schematic structural diagram of an embodiment of a protection device according to the present utility model; fig. 3 is a schematic view of the internal structure of the guard in the embodiment of fig. 2. As shown in fig. 2 and 3, the protection device 10 includes a housing 200 and a circuit board 100. Wherein the housing 200 is formed with a receiving cavity (not shown) while the housing 200 is used as a first ground, it will be appreciated that the housing 200 of the guard 10 is in contact with a chassis or a body shell of an electronic device, i.e., the housing 200 of the guard 10 is in communication with both the body ground and the body ground of the electronic device, and the housing 200 is used as a first ground. The housing 200, when acting as a first ground, may be used to bleed off surge energy. The circuit board 100 is disposed in the accommodating cavity, and a protection circuit 110 is disposed on the circuit board 100, wherein the protection circuit 110 is used for isolating surge energy. It will be appreciated that the protection circuit 110 serves to isolate surge energy entering the signal line through the signal ground.

The protection device 10 provided by the utility model is provided with the shell 200 and the circuit board 100, wherein the circuit board 100 is provided with the protection circuit 110, and the circuit board 100 is arranged in the accommodating cavity of the shell 200. In the above manner, the case 200 can be used to discharge surge energy when acting as the first ground; further, the protection circuit 110 is used for isolating the surge energy, i.e. cutting off the signal ground loop, and blocking the ground impact energy, so as to reduce the damage of the surge energy to the electronic components and improve the safety of the vehicle-mounted electronic system.

Optionally, the housing 200 comprises an annular housing (not labeled in the figures). The annular shell comprises two ends which are not sealed, and a cavity between the two ends is the accommodating cavity. Wherein the expanded shape of the annular housing may be rectangular. The guard 10 further includes a first port 300 disposed at one end of the annular housing and a second port 400 disposed at the other end of the annular housing. The circuit board 100 is located between the first port 300 and the second port 400, and the first port 300 and the second port 400 are electrically connected with the protection circuit 110.

The protection device 10 of the present embodiment includes a first port 300 and a second port 400 electrically connected to the protection circuit 110, wherein the housing 200 includes an annular housing, the first port 300 is disposed at one end of the annular housing, and the second port 400 is disposed at the other end of the annular housing. In this way, the protection device 10 can be applied between signal ports of the vehicle-mounted electronic system in a plugging manner, so as to reduce the installation difficulty of the protection device 10.

In other embodiments, the first port 300 and the second port 400 may be ports corresponding to signal ports, and the types of the first port 300 and the second port 400 are not particularly limited herein.

Optionally, the first port 300 and the second port 400 are connected through a signal bus, and the protection circuit 110 is connected in series between the signal buses of the first port 300 and the second port 400.

Optionally, referring to fig. 4, fig. 4 is a schematic structural diagram of an embodiment of the protection circuit in the embodiment of fig. 2. As shown in fig. 4, the protection circuit 110 includes at least a first protection circuit 111 and a second protection circuit 112. The input end of the first protection circuit 111 is connected to the signal bus, and the output end of the first protection circuit is connected to the second ground wire for absorbing static electricity and surge energy. It is understood that the second ground refers to signal ground. The second protection circuit 112 is connected in series between the connection point of the first protection circuit 111 and the signal bus and the second port 400, and is used for isolating surge energy.

In some embodiments, the signal bus may be a controller area network (Controller Area Network, CAN) signal bus in CAN communication technology.

The electrical overstress is a common damage cause of the components, and the electrical overstress is represented by a large amount of heat energy generated by overvoltage or overcurrent, so that the internal temperature of the components is too high to damage the components. The voltage and current exceeding the stable values, namely surge energy, cause the internal temperature of the component to be too high, thereby damaging the component. When the protection circuit 110 works, when surge energy caused by overvoltage or overcurrent passes through the first protection circuit 111, the first protection circuit 111 can absorb most static electricity and surge energy so as to reduce the static electricity and surge energy, and when the surge energy attenuated by the first protection circuit 111 passes through the second protection circuit 112, the second protection circuit 112 can prevent the surge energy from entering a signal circuit or a vehicle-mounted electronic system of a later stage through the second port 400, so that the surge energy passing through the second port 400 is further reduced, the probability that the residual surge energy damages an electronic element is reduced, and the safety of the vehicle-mounted electronic system is further improved.

The protection circuit 110 of the present utility model is provided with the first protection circuit 111 and the second protection circuit 112, wherein the input end of the first protection circuit 111 is connected with the signal bus, the output end of the first protection circuit is connected with the second ground wire, and the second protection circuit 112 is connected in series between the connection point of the first protection circuit 111 and the signal bus and the second port 400. In this way, when the surge energy caused by the excessively high voltage or current passes through the first protection circuit 111, the first protection circuit 111 can absorb most of static electricity and the surge energy so as to reduce the static electricity and the surge energy, and when the surge energy attenuated by the first protection circuit 111 passes through the second protection circuit 112, the second protection circuit 112 can prevent the surge energy from being directly connected into the rear-stage electronic system through the second port 400, so that the surge energy entering the electronic system is further reduced, the probability of damaging the electronic system by residual surge energy is reduced, and the safety of the vehicle-mounted electronic system is further improved.

Optionally, referring to fig. 5, fig. 5 is a schematic structural diagram of an embodiment of the first protection circuit in the embodiment of fig. 4. When the signal bus is a CAN signal bus, the CAN signal bus includes a dominant line can_h and a recessive line can_l, as shown in fig. 5, the first protection circuit 111 includes at least two first protection sub-circuits 111a, an input end of one first protection sub-circuit 111a is connected to the dominant line can_h in the CAN signal bus, an output end of the first protection sub-circuit is connected to the second ground line, and the first protection sub-circuit 111a electrically connected to the dominant line can_h in the CAN signal bus CAN receive static and surge energy flowing through the dominant line can_h. The input end of the other first protection sub-circuit 111a is connected to the recessive line can_l in the CAN signal bus, and the output end of the other first protection sub-circuit is connected to the second ground wire, so that the first protection sub-circuit 111a electrically connected to the recessive line can_l in the CAN signal bus CAN receive static electricity and surge energy flowing through the recessive line can_l. The first protection circuit 111 may further include 4, 6, etc. first protection sub-circuits 111a, and in the same connection manner as described above, the first protection sub-circuits with equal number are disposed on the dominant line can_h and the recessive line can_l in the CAN signal bus.

The first protection circuit 111 of this embodiment, through setting up at least two first protection subcircuits 111a, inserts dominant line can_h in the CAN signal bus and recessive line can_l in the CAN signal bus respectively, when surge energy flows through recessive line can_l or dominant line can_h, or when flowing through recessive line can_l and dominant line can_h simultaneously, first protection subcircuit 111a CAN all absorb static and surge energy on arbitrary one or two kinds of signal lines to reduce the probability that surge energy damages electronic component, and then improve on-vehicle electronic system's security.

Optionally, the first guard sub-circuit 111a includes a high power transientAny one of a suppressor diode, a semiconductor discharge tube, a piezoresistor and a gas discharge tube is correspondingly connected in parallel between the dominant line and the second ground line and between the recessive line and the second ground line. Wherein the high-power transient suppression diode is a diode type high-efficiency protection device, and can take the form of 10 when surge, electrostatic discharge and other voltages occur, namely when the two poles of the high-power transient suppression diode are impacted by reverse transient high energy ^-9 The second-level speed changes the high resistance between the two poles into low resistance, absorbs the surge energy of thousands of watts, enables the voltage between the two poles to be clamped at a preset value, effectively protects the precise components in the electronic circuit from being damaged by surge pulses, and plays a role in suppressing the transient voltage of the high-power transient suppression diode.

Referring to fig. 6, fig. 6 is a schematic structural diagram of an embodiment of the first protection sub-circuit in the embodiment of fig. 5. As shown in fig. 6, the output end of the first high-power transient suppression diode D111 is connected to the dominant line can_h in the CAN signal bus, and the output end thereof is connected to the second ground line. The output end of the second high-power transient suppression diode D112 is connected with a recessive line CAN_L in the CAN signal bus, and the output end of the second high-power transient suppression diode D is connected with a second ground wire.

Optionally, referring to fig. 7, fig. 7 is a schematic structural diagram of an embodiment of the second protection circuit in the embodiment of fig. 4. As shown in fig. 7, the second protection circuit 112 includes at least two second protection sub-circuits 112a, wherein one second protection sub-circuit 112a is connected in series between the connection point of the first protection sub-circuit 111a and the dominant line can_h and the second port 400 to isolate the surge energy on the dominant line can_h. The other second protection sub-circuit 112a is connected in series between the connection point of the first protection sub-circuit 111a and the recessive line can_l and the second port 400 to isolate the surge energy on the recessive line can_l. The second protection circuit 112 may further include 4, 6, etc. second protection sub-circuits 112a, and in the same connection manner as described above, the second protection sub-circuits with equal number are set on the dominant line can_h and the recessive line can_l in the CAN signal bus.

The second protection circuit 112 of this embodiment is provided with at least two second protection sub-circuits 112a, where the second protection sub-circuits 112a are respectively connected in series between the node where the first protection circuit 111 is connected to the dominant line can_h and the second port 400, and between the node where the first protection circuit 111 is connected to the recessive line can_l and the second port 400, and when the surge energy attenuated by the first protection circuit 111 is connected in series to the recessive line can_l or the dominant line can_h, or when the surge energy flows through both the recessive line can_l and the dominant line can_h, the second protection sub-circuits 112a CAN absorb the surge energy on any one or two signal lines, so as to isolate the surge energy.

Optionally, the second protection sub-circuit 112a includes a transient blocking unit (refer to fig. 8), an input end of the transient blocking unit is connected to a connection point of the first protection sub-circuit 111a and the dominant line can_h, or an input end of the transient blocking unit is connected to a connection point of the first protection sub-circuit 111a and the recessive line can_l, and an output end of the transient blocking unit is connected to the second ground line. The transient blocking unit has high response speed, becomes a high-resistance state after response, plays a role in blocking a surge path in the circuit, and prevents a large-energy surge from directly entering a later-stage circuit in series.

Referring to fig. 8, fig. 8 is a schematic diagram illustrating an embodiment of a second protection sub-circuit in the embodiment of fig. 7. As shown in fig. 8, the input end of the first transient blocking unit U211 is connected to the connection point of the first protection sub-circuit 111a and the dominant line can_h, and the output end of the first transient blocking unit U211 is connected to the second ground line. The input end of the second transient blocking unit U212 is connected to the connection point of the first protection sub-circuit 111a and the recessive line can_l, and the output end of the second transient blocking unit U212 is connected to the second ground line.

The second protection sub-circuit 112a of the embodiment, by setting the transient blocking unit, changes the transient blocking unit into a high-resistance state when the surge energy attenuated by the first protection circuit 111 is connected in series with the transient blocking unit, and prevents a large energy surge from being directly connected in series with the later-stage circuit, so that the damage of the surge energy to the electronic element is reduced, and the safety of the vehicle-mounted electronic system is improved; further, the transient blocking unit plays a role of blocking a surge path, and prevents current impact formed in the power supply circuit from influencing the normal operation of the network when the current of the front and rear circuits changes.

Optionally, the second protection circuit 112 further includes a transient suppression diode (refer to fig. 9), one end of which is connected to the input terminal of the transient blocking unit, and the other end of which is connected to the output terminal of the transient blocking unit. The transient suppression diode may be a high power transient suppression diode or a low power transient suppression diode, and is not particularly limited herein. Referring to fig. 9, fig. 9 is a schematic diagram of a second protection sub-circuit according to another embodiment of the embodiment of fig. 7. As shown in fig. 9, one end of the first transient suppression diode D221 is connected to the input terminal of the first transient blocking unit U211, and the other end thereof is connected to the output terminal of the first transient blocking unit U211. One end of the second transient suppression diode D222 is connected to the input end of the second transient blocking unit U212, and the other end thereof is connected to the output end of the second transient blocking unit U212.

The second protection sub-circuit 112a of the embodiment is provided with the transient suppression diode connected in parallel with the transient blocking unit, so that the second protection sub-circuit 112a has high response speed, can be quickly converted into a high-resistance protection circuit, cuts off the path of surge energy in time, and protects itself from damage by utilizing the static electricity and surge absorption characteristics of the transient suppression diode.

Alternatively, other embodiments of the second guard sub-circuit 112a may include a positive temperature coefficient thermistor to absorb surge energy.

Optionally, referring to fig. 10, fig. 10 is a schematic structural diagram of another embodiment of a protection circuit provided by the present utility model. As shown in fig. 10, the protection circuit 110 further includes a third protection circuit 113, an input end of the third protection circuit 113 is connected to a signal bus between the second protection circuit 112 and the second port 400, and an output end of the third protection circuit is connected to a second ground line for absorbing static electricity and surge energy.

The protection circuit 110 of the present embodiment further includes a third protection circuit 113, where an input end of the third protection circuit 113 is connected to the signal bus between the second protection circuit 112 and the second port 400, and an output end of the third protection circuit is connected to the second ground. By the above method, the third protection circuit 113 is used for reducing the residual static electricity and surge energy after being attenuated by the first protection circuit 111 and the second protection circuit 112, further reducing the damage of the surge energy to the electronic components, and improving the safety of the vehicle-mounted electronic system.

Optionally, referring to fig. 11, fig. 11 is a schematic structural diagram of an embodiment of the third protection circuit in the embodiment of fig. 10. As shown in fig. 11, when the signal bus is a CAN signal bus, the CAN signal bus includes a dominant line can_h and a recessive line can_l; the third protection circuit 113 includes at least two third protection sub-circuits 113a, wherein an input end of one third protection sub-circuit 113a is connected to the dominant line can_h, and an output end thereof is connected to the second ground line. The input end of the other third protection sub-circuit 113a is connected to the recessive line can_l, and the output end of the third protection sub-circuit is connected to the second ground line.

In the third protection circuit 113 of this embodiment, at least two third protection sub-circuits 113a are provided, when the surge energy attenuated by the first protection circuit 111 and the second protection circuit 112 is connected in series to the recessive line can_l or the dominant line can_h, or flows through the recessive line can_l and the dominant line can_h at the same time, the third protection sub-circuits 113a CAN absorb the surge energy on any one or two signal lines, so as to further absorb residual static electricity and surge energy, further reduce the damage of the surge energy and static electricity to electronic elements, and improve the safety of the vehicle-mounted electronic system.

Optionally, the third protection sub-circuit 113a includes a low-power transient suppression diode, an input terminal of the low-power transient suppression diode is connected to the dominant line can_h between the dominant line can_h and the second port 400, or the input terminal of the low-power transient suppression diode is connected to the dominant line can_l between the dominant line can_l and the second port 400, and an output terminal of the low-power transient suppression diode is connected to the second ground line. Or the low-power transient suppression diode can be replaced by any one of a semiconductor discharge tube, a piezoresistor and a gas discharge tube. Referring to fig. 12, fig. 12 is a schematic diagram illustrating an embodiment of a third protection sub-circuit in the embodiment of fig. 11. As shown in fig. 12, a first end of the first low-power transient suppression diode D311 is connected to the dominant line can_h between the dominant line can_h and the second port 400, and a second end of the first low-power transient suppression diode D311 is connected to the second ground. A first end of the second low power transient suppression diode D312 is connected to the dominant line can_l between the dominant line can_l and the second port 400, and a second end of the second low power transient suppression diode D312 is connected to a second ground line.

The third protection sub-circuit 113a of the present embodiment can further reduce damage of the electronic component by the surge energy by providing a low-power transient suppression diode to absorb the residual surge energy and static electricity.

Referring to fig. 13, fig. 13 is a schematic structural diagram of a protection circuit according to another embodiment of the present utility model. As shown in fig. 13, the signal bus includes a CAN signal bus including a dominant line can_h and a recessive line can_l, and the dominant line can_h between the first port 300 and the second port 400 is provided with: a first end of the first high-power transient suppression diode D111 is connected to a dominant line CAN_H, a second end of the first high-power transient suppression diode D111 is connected with a first end of the first semiconductor discharge tube D121, and a second end of the first semiconductor discharge tube D121 is connected with a second ground line; the first transient blocking unit U211 is arranged in parallel with the first transient suppressing diode D221, and a first end of the first transient blocking unit U211 is connected to a connection point of the first high-power transient suppressing diode D111 to the dominant line can_h, a second end of the first transient blocking unit U211 is connected to the second port 400, and a second end of the first transient blocking unit U211 is connected to a first end of the first low-power transient suppressing diode D311, and a second end of the first low-power transient suppressing diode D311 is connected to the second ground line. The recessive lines can_l between the first port 300 and the second port 400 are provided with: a first end of the second high-power transient suppression diode D112 is connected to a dominant line CAN_L, a second end of the second high-power transient suppression diode D112 is connected with a first end of the second semiconductor discharge tube D122, and a second end of the second semiconductor discharge tube D122 is connected with a second ground line; the second transient blocking unit U212 is arranged in parallel with the second transient suppression diode D222, and a first end of the second transient blocking unit U212 is connected with a connection point of the second high-power transient suppression diode D112 to the dominant line can_l, a second end of the second transient blocking unit U212 is connected with the second port 400, and a second end of the second transient blocking unit U212 is connected with a first end of the second low-power transient suppression diode D312, and a second end of the second low-power transient suppression diode D312 is connected with a second ground line.

The present utility model further provides a vehicle, referring to fig. 14, fig. 14 is a schematic structural diagram of an embodiment of the vehicle provided by the present utility model, and as shown in fig. 14, the vehicle 20 includes a protection device 210, where the protection device 210 is any one of the protection devices in the above protection device embodiments.

In the description of the present utility model, a description of the terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, mechanism, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present utility model. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, mechanisms, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

The foregoing is only the embodiments of the present utility model, and therefore, the patent scope of the utility model is not limited thereto, and all equivalent structures or equivalent processes using the descriptions of the present utility model and the accompanying drawings, or direct or indirect application in other related technical fields, are included in the scope of the utility model.

Claims (12)

1. A protective device, comprising:

the shell is used as a first ground wire to release surge energy;

the circuit board is arranged in the accommodating cavity, and a protection circuit is arranged on the circuit board;

the protection circuit is used for isolating surge energy.

2. The guard of claim 1, wherein the housing comprises an annular housing, the guard comprising:

a first port provided at one end of the annular housing;

a second port arranged at the other end of the annular shell;

the circuit board is located between the first port and the second port, and the first port and the second port are electrically connected with the protection circuit.

3. The guard of claim 2, wherein the first port and the second port are connected by a signal bus, and the guard circuit is connected in series between the signal buses of the first port and the second port.

4. A protective device according to claim 3, wherein the protection circuit comprises at least:

the input end of the first protection circuit is connected with the signal bus, the output end of the first protection circuit is connected with the second ground wire, and the first protection circuit is used for absorbing static electricity and surge energy;

the second protection circuit is connected in series between the connection point of the first protection circuit and the signal bus and the second port, and the second protection circuit is used for isolating surge energy.

5. The guard of claim 4, wherein the signal bus comprises a dominant line and a recessive line;

the first protection circuit comprises at least two first protection subcircuits, the input end of one first protection subcircuit is connected with the dominant line, and the output end of the first protection subcircuit is connected with the second ground line so as to receive static electricity and surge energy of the dominant line;

the input end of the other first protection subcircuit is connected with the hidden line, and the output end of the other first protection subcircuit is connected with the second ground wire so as to receive static electricity and surge energy of the hidden line.

6. The guard of claim 5, wherein the first guard sub-circuit comprises:

a high power transient suppression diode, a semiconductor discharge tube, or any one of a varistor or a gas discharge tube, and the high power transient suppression diode, the semiconductor discharge tube, the varistor, the gas discharge tube are respectively connected in parallel between the dominant line and the second ground line, and between the recessive line and the second ground line.

7. The guard of claim 5, wherein the second guard circuit comprises at least two second guard sub-circuits, one of the second guard sub-circuits being connected in series between a connection point of the first guard sub-circuit to the dominant line and the second port to isolate surge energy on the dominant line;

the other second protection subcircuit is connected in series between the connection point of the other first protection subcircuit and the hidden line and the second port so as to isolate surge energy on the hidden line.

8. The guard of claim 7, wherein the second guard sub-circuit comprises:

the input end of the transient blocking unit is connected with the connection point of the first protection subcircuit and the dominant line or the recessive line, and the output end of the transient blocking unit is connected with the second port;

and one end of the transient suppression diode is connected with the input end of the transient blocking unit, and the other end of the transient suppression diode is connected with the output end of the transient blocking unit.

9. The protective apparatus of claim 4, wherein the protection circuit further comprises:

and the input end of the third protection circuit is connected with the signal bus between the second protection circuit and the second port, and the output end of the third protection circuit is connected with the first ground wire and is used for absorbing static electricity and discharging surge energy.

10. The guard of claim 9, wherein the signal bus comprises a dominant line and a recessive line; the third protection circuit comprises at least two third protection subcircuits, the input end of one third protection subcircuit is connected with the dominant line, and the output end of the third protection subcircuit is connected with the first ground line;

the input end of the other third protection subcircuit is connected with the hidden line, and the output end of the third protection subcircuit is connected with the first ground line.

11. The guard of claim 10, wherein the third guard sub-circuit comprises:

a low power transient suppression diode, any one of a semiconductor discharge tube, a varistor, a gas discharge tube, and the low power transient suppression diode, any one of the semiconductor discharge tube, the varistor, the gas discharge tube are respectively connected in parallel between the dominant line or the recessive line and the first ground line.

12. A vehicle, characterized by comprising:

the protective device of any one of claims 1-11.