CN220325271U

CN220325271U - Safety circuit, electronic safety device and vehicle

Info

Publication number: CN220325271U
Application number: CN202322012863.8U
Authority: CN
Inventors: 乔中帅; 刘晓军; 张开川; 刘允东
Original assignee: Shanghai Jidu Automobile Co Ltd
Current assignee: Shanghai Jidu Automobile Co Ltd
Priority date: 2023-07-27
Filing date: 2023-07-27
Publication date: 2024-01-09
Anticipated expiration: 2033-07-27

Abstract

The utility model discloses a safety circuit, an electronic safety device and a vehicle. The safety circuit comprises a current detection circuit, a switching circuit, a controller, a power input end and a power output end which are separately arranged on the circuit board; the series circuit formed by the current detection circuit and the switch circuit in series is connected between the power input end and the power output end; the output end of the current detection circuit is connected with the first input end of the controller, and the output end of the controller is connected with the control end of the switching circuit.

Description

Safety circuit, electronic safety device and vehicle

Technical Field

The present utility model relates to the field of electronic technology, and more particularly, to a safety circuit, an electronic safety device, and a vehicle.

Background

In an automotive power distribution system, fuses are typically provided for the purpose of ensuring power distribution safety. When the current is excessive, the fuse will blow. However, the fuse takes a certain time to blow, and the wire harness receives a large current before the fuse blows. In order to avoid the situation that the wire harness smokes under the action of high current, the wire diameter of the wire harness is generally increased. This approach increases the weight of the vehicle and also increases the cost of the wiring harness. In order to solve the above technical problems, an integrated chip Efuse is proposed in the prior art, which can be automatically turned off when the current is too large. In the vehicle, however, if the integrated chip is used in a large amount due to the large number of loads, the cost of the vehicle is greatly increased.

Disclosure of Invention

It is an object of the present utility model to provide a new solution for securing power distribution.

According to a first aspect of the present utility model, there is provided a safety circuit comprising a current detection circuit, a switching circuit, a controller, a power supply input terminal and a power supply output terminal separately provided on a circuit board;

the series circuit formed by the current detection circuit and the switch circuit in series is connected between the power input end and the power output end;

the output end of the current detection circuit is connected with the first input end of the controller, and the output end of the controller is connected with the control end of the switching circuit.

Optionally, a first end of the current detection circuit is connected with the power input end, a second end of the current detection circuit is connected with a first end of the switch circuit, and a second end of the switch circuit is connected with the power output end.

Optionally, a first end of the switching circuit is connected to the power input end, a second end of the switching circuit is connected to the first end of the current detection circuit, and a second end of the current detection circuit is connected to the power output end.

Optionally, the switch circuit includes a PMOS transistor and an NMOS transistor;

the source of the PMOS tube is a first end of the switch circuit, the drain of the PMOS tube is a second end of the switch circuit, and the gate of the NMOS tube is a control end of the switch circuit;

the source electrode of the PMOS tube is connected with the grid electrode of the PMOS tube through a first resistor, the grid electrode of the PMOS tube is connected with the drain electrode of the NMOS tube, the source electrode of the NMOS tube is grounded, the grid electrode of the NMOS tube is connected with the output end of the controller through a second resistor, and the source electrode of the NMOS tube is connected with the grid electrode of the NMOS tube through a third resistor.

Optionally, the temperature detection circuit is used for detecting the temperature of the PMOS tube, and the output end of the temperature detection circuit is connected with the second input end of the controller;

the controller is used for controlling the switching circuit to be switched on or switched off according to the output signal of the temperature detection circuit.

Optionally, the temperature detection circuit includes a fourth resistor and a fifth resistor, where the fourth resistor is a thermistor, and the fourth resistor is configured to be attached to a surface of the PMOS tube;

the first end of the fourth resistor is connected with the second input end of the controller and the first end of the fifth resistor respectively, the second end of the fifth resistor is grounded, and the second end of the fourth resistor is connected with the power supply end of the controller.

Optionally, the current detection circuit includes a sixth resistor and an operational amplifier;

the two ends of the sixth resistor are respectively a first end of the current detection circuit and a second end of the current detection circuit, and the output end of the operational amplifier is the output end of the current detection circuit;

and two ends of the sixth resistor are respectively connected with the non-inverting input end of the operational amplifier and the inverting input end of the operational amplifier.

Optionally, the power supply further comprises a diode, wherein the cathode of the diode is connected with the power supply output end, and the anode of the diode is grounded.

Optionally, the filter further comprises a first filter capacitor and a second filter capacitor;

the first end of the first filter capacitor is connected with the power supply output end, and the second end of the first filter capacitor is grounded;

the first end of the second filter capacitor is connected with the power input end, and the second end of the second filter capacitor is grounded.

According to a second aspect of the present utility model there is provided an electronic fuse comprising the fuse circuit of the first aspect of the present utility model.

According to a third aspect of the present utility model there is provided a vehicle having an electronic fuse according to the second aspect of the present utility model.

According to one embodiment of the utility model, a current detection circuit is arranged on the circuit board, the current detection circuit detects the current when the load is supplied with power, and the controller calculates the corresponding energy according to the current and compares the energy with a pre-configured energy threshold value so as to control the switch circuit to be turned on or turned off. When the energy is higher, the switch circuit can be disconnected in time, phenomena such as smoking and ignition of the wire harness under the condition of high current are avoided, and the safety is improved. Meanwhile, the time for bearing large current by the wire harness is reduced, the wire diameter of the wire harness can be reduced while safety is ensured, and then the cost of the wire harness is reduced, and meanwhile, the weight of a vehicle is reduced. In addition, the current detection circuit, the switching circuit and the controller are arranged on the circuit board separately, so that the cost of the safety circuit can be reduced compared with an integrated chip.

Other features of the present utility model and its advantages will become apparent from the following detailed description of exemplary embodiments of the utility model, which proceeds with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the utility model and together with the description, serve to explain the principles of the utility model.

Fig. 1 is a schematic diagram of a protection circuit in one embodiment of the present application.

Fig. 2 is a schematic diagram of a protection circuit in another embodiment of the present application.

Fig. 3 is a schematic diagram showing specific connection of the protection circuit in one embodiment of the present application.

Fig. 4 is a schematic diagram showing specific connection of the protection circuit in another embodiment of the present application.

Detailed Description

Various exemplary embodiments of the present utility model will now be described in detail with reference to the accompanying drawings. It should be noted that: the relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present utility model unless it is specifically stated otherwise.

The following description of at least one exemplary embodiment is merely exemplary in nature and is in no way intended to limit the utility model, its application, or uses.

Techniques, methods, and apparatus known to one of ordinary skill in the relevant art may not be discussed in detail, but are intended to be part of the specification where appropriate.

In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of exemplary embodiments may have different values.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.

As shown in fig. 1 and 2, the present embodiment describes a safety circuit including a current detection circuit, a switching circuit, a controller, a power supply input terminal, and a power supply output terminal, which are separately provided on a circuit board.

The series circuit formed by the current detection circuit and the switch circuit in series is connected between the power input end and the power output end.

The safety circuit in this embodiment can be used in the field of vehicles. The power input end can be connected with a power supply bus of the vehicle, and the power output end is used for being connected with a load of the vehicle. The power supply bus may be a low voltage power supply bus of a vehicle, the load being a low voltage load of the vehicle, such as a speaker of the vehicle.

The current detection circuit can detect the current in the safety circuit in real time and send the detection result to the controller. The controller calculates the energy passing through the safety circuit based on the current. The calculation formula of the energy is q=i×i×t, where Q represents the energy, I represents the current, and T represents the duration of the current. If the energy is large, the temperature of the wire harness is possibly high, so that safety problems such as smoke and fire of the wire harness can be caused, and at the moment, the switch circuit is required to be disconnected to stop supplying power to the load.

When the energy is large, the controller sends a signal to the control end of the switching circuit to control the switching circuit to be disconnected. When the energy is small, the switch circuit is kept in a conducting state. A plurality of time thresholds and corresponding energy thresholds can be preset, and whether the switch circuit needs to be controlled to be disconnected is judged through the time thresholds and the energy thresholds. For example, time thresholds T1, T2 and T3 are preset in order from small to large, and the energy thresholds corresponding to the three time thresholds are Q1, Q2 and Q3, respectively. If the duration T of the current is less than the time threshold T1, then judging whether the energy calculated by the controller exceeds the energy threshold Q1, and if so, controlling the switch circuit to be opened. If the duration T of the current is greater than the time threshold T1 and less than the time threshold T2, then a determination is made as to whether the energy calculated by the controller exceeds the energy threshold Q2, and if so, then the switching circuit is controlled to open. If the duration T of the current is greater than the time threshold T2 and less than the time threshold T3, then a determination is made as to whether the energy calculated by the controller exceeds the energy threshold Q3, and if so, then the switching circuit is controlled to open.

There are a plurality of loads in the vehicle, and the energization time of each load is different. Some loads need to be powered all the time after the vehicle is started, such as the vehicle center control. While some loads are energized only when needed, such as the turn signal lights of a vehicle. For each load of the vehicle, the safety circuit of the present application may be provided between the load and the power supply bus. Since the power of each load is different, the current when the load is energized is also different, and thus the energy threshold value corresponding to each load is also different. And for different wire harnesses, parameters such as material, wire diameter and the like of the wire harnesses are different, the energy which can be born by the different wire harnesses is also different, and the wire harnesses can be protected by configuring different energy thresholds and time thresholds.

The controller can be a micro control unit (Micro controller Unit, MCU) with lower cost. The controller is provided with a first input end, and receives the detection result of the current detection circuit through the first input end. The controller also has an output terminal through which the controller can send different control signals to the switching circuit to control the switching circuit to be turned on or off.

In this embodiment, a current detection circuit is disposed on a circuit board, a current when power is supplied to a load is detected by the current detection circuit, and a controller calculates corresponding energy according to the current and compares the energy with a pre-configured energy threshold value, thereby controlling the switch circuit to be turned on or off. When the energy is higher, the switch circuit can be disconnected in time, phenomena such as smoking and ignition of the wire harness under the condition of high current are avoided, and the safety is improved. Meanwhile, the time for bearing large current by the wire harness is reduced, the wire diameter of the wire harness can be reduced while safety is ensured, and then the cost of the wire harness is reduced, and meanwhile, the weight of a vehicle is reduced. In addition, the current detection circuit, the switching circuit and the controller are arranged on the circuit board separately, so that the cost of the safety circuit can be reduced compared with an integrated chip.

In one embodiment, as shown in fig. 1, the first end of the current detection circuit is connected to the power input terminal, the second end of the current detection circuit is connected to the first end of the switching circuit, and the second end of the switching circuit is connected to the power output terminal.

In another embodiment. As shown in fig. 2, the first end of the switch circuit is connected to the power input end, the second end of the switch circuit is connected to the first end of the current detection circuit, and the second end of the current detection circuit is connected to the power output end.

In this embodiment, the switch circuit includes a PMOS transistor Q1 and an NMOS transistor Q2.

The source of the PMOS tube Q1 is the first end of the switch circuit, the drain of the PMOS tube Q1 is the second end of the switch circuit, and the gate of the NMOS tube Q2 is the control end of the switch circuit.

The source of the PMOS tube Q1 is connected with the grid of the PMOS tube Q1 through a first resistor R1, the grid of the PMOS tube Q1 is connected with the drain of the NMOS tube Q2, the source of the NMOS tube Q2 is grounded, the grid of the NMOS tube Q2 is connected with the output end of the controller through a second resistor R2, and the source of the NMOS tube Q2 is connected with the grid of the NMOS tube Q2 through a third resistor R3.

The PMOS tube Q1 has two states of on and off. When the PMOS tube Q1 is turned on, the source electrode of the PMOS tube Q1 is turned on with the drain electrode of the PMOS tube Q1, and current flows from the source electrode of the PMOS tube Q1 to the drain electrode of the PMOS tube Q1. By providing different voltages to the gate of the PMOS transistor Q1, the PMOS transistor Q1 can be controlled to be turned on or off.

The NMOS tube Q2 also has an on state and an off state, and the grid electrode of the NMOS tube Q2 is connected with the output end of the controller. The controller provides different voltages to the grid electrode of the NMOS tube Q2, so that the on-off state of the NMOS tube Q2 can be controlled. When the controller outputs a high level to the gate of the NMOS, the NMOS transistor Q2 is turned on. When the controller outputs a low level to the gate of the NMOS transistor Q2, the NMOS transistor Q2 is turned off.

The drain electrode of the NMOS transistor Q2 is connected to the gate electrode of the PMOS transistor Q1, and when the NMOS transistor Q2 is turned off, no loop is formed between the source electrode and the gate electrode of the PMOS transistor Q1, so that the source voltage of the PMOS transistor Q1 is the same as the gate voltage of the PMOS transistor Q1, and the on condition of the PMOS transistor Q1 is not satisfied at this time, and the PMOS transistor Q1 is in an off state.

When the NMOS transistor Q2 is turned on, the source of the NMOS transistor Q2 is turned on with the drain of the NMOS transistor Q2. Since the source of the NMOS transistor Q2 is grounded and the drain of the NMOS transistor Q2 is connected to the gate of the PMOS transistor Q1, the gate of the PMOS transistor Q1 is grounded. Because the first resistor R1 exists between the source electrode and the grid electrode of the PMOS tube Q1, the source electrode voltage of the PMOS tube Q1 is higher than the grid electrode voltage of the PMOS tube Q1 by the first resistor R1, and the PMOS tube Q1 is conducted.

As shown in fig. 3, in one embodiment, the power input terminal is connected to the first terminal of the current detection circuit, the source of the PMOS transistor Q1 is connected to the second terminal of the current detection circuit, and the drain of the PMOS transistor Q1 is connected to the power output terminal.

In another embodiment, as shown in fig. 4, the power input end is connected to the source of the PMOS transistor Q1, the drain of the PMOS transistor Q1 is connected to the first end of the current detection circuit, and the second end of the current detection circuit is connected to the power output end.

According to the embodiment, the PMOS tube Q1 and the NMOS tube Q2 are matched with each other, the automatic on-off of the PMOS is realized through the controller, and the circuit structure is simple and the cost is low.

In this embodiment, the safety circuit further includes a temperature detection circuit for detecting the temperature of the PMOS transistor Q1, and an output end of the temperature detection circuit is connected to the second input end of the controller. The controller is used for controlling the switching circuit to be switched on or switched off according to the output signal of the temperature detection circuit.

The temperature detection circuit can detect the temperature of the PMOS tube Q1 and output a corresponding voltage signal to the controller according to the temperature of the PMOS tube Q1. The controller can output different control signals according to the temperature of the PMOS tube Q1. When the temperature of the PMOS tube Q1 is higher, the PMOS tube Q1 is controlled to be disconnected. And when the temperature of the PMOS tube Q1 is lower, the PMOS tube Q1 is conducted.

According to the embodiment, the temperature detection circuit is arranged in the safety circuit, the temperature of the PMOS tube Q1 is detected through the temperature detection circuit, the PMOS tube Q1 is disconnected when the temperature of the PMOS tube Q1 is higher, and overheat damage of the PMOS tube Q1 is avoided.

In this embodiment, the temperature detection circuit includes a fourth resistor R4 and a fifth resistor R5, where the fourth resistor R4 is a thermistor, and the fourth resistor R4 is configured to be attached to the surface of the PMOS transistor Q1.

The first end of the fourth resistor R4 is respectively connected with the second input end of the controller and the first end of the fifth resistor R5, the second end of the fifth resistor R5 is grounded, and the second end of the fourth resistor R4 is connected with the power supply end of the controller.

The resistance value of the thermistor may vary with temperature. The thermistor includes a positive temperature coefficient thermistor and a negative temperature coefficient thermistor. The resistance value of the positive temperature coefficient thermistor increases with an increase in temperature, and the resistance value of the negative temperature coefficient thermistor decreases with an increase in temperature.

Because the fourth resistor R4 is attached to the surface of the PMOS transistor Q1, the resistance value of the fourth resistor R4 will change due to the temperature of the PMOS transistor Q1. Since the second terminal of the fourth resistor R4 is connected to the power supply terminal of the controller, the voltage at the second terminal of the fourth resistor R4 remains unchanged. When the resistance value of the fourth resistor R4 changes, the voltage supplied to the second input terminal of the controller also changes. The controller may output different signals to the NMOS transistor Q2 according to the voltage of the second input terminal. For example, when the voltage at the second input end of the controller indicates that the temperature of the PMOS transistor Q1 is higher, the controller outputs a low level to the gate of the NMOS transistor Q2, so that the NMOS transistor Q2 is turned off, and the PMOS transistor Q1 is turned off. When the voltage of the second input end of the controller indicates that the temperature of the PMOS tube Q1 is low, the controller outputs a high level to the grid electrode of the NMOS tube Q2, and when the NMOS tube Q2 is conducted, the PMOS tube Q1 is conducted.

For example, the fourth resistor R4 is a negative temperature coefficient thermistor, and when the temperature of the PMOS transistor Q1 increases, the resistance value of the fourth resistor R4 decreases. The higher the temperature of the PMOS transistor Q1, the lower the resistance of the fourth resistor R4, and thus the higher the voltage received by the second input terminal of the controller. A voltage threshold can be preset in the controller, when the voltage received by the second input end of the controller is greater than the voltage threshold, the temperature of the PMOS transistor Q1 is higher, and at this time, the output end of the controller outputs a low level to the gate of the NMOS transistor Q2, so that the NMOS transistor Q2 is turned off, and the PMOS transistor Q1 is turned off. When the voltage received by the second input end of the controller is lower than the voltage threshold, the temperature of the PMOS tube Q1 is lower, and at the moment, the output end of the controller outputs a high level to the grid electrode of the NMOS tube Q2, so that the NMOS tube Q2 is conducted, and the PMOS tube Q1 is conducted.

Because the resistance value of the fourth resistor R4 varies with the temperature of the PMOS transistor Q1, when the resistance value of the fourth resistor R4 is lower, the current between the fourth resistor and the second input terminal of the controller is larger. The fifth resistor R5 is arranged to shunt, so that the current between the fourth resistor and the second input end of the controller is reduced, and the controller is protected.

In this embodiment, the current detection circuit includes a sixth resistor R6 and an operational amplifier OP1. The two ends of the sixth resistor R6 are the first end of the current detection circuit and the second end of the current detection circuit, respectively, and the output end of the operational amplifier OP1 is the output end of the current detection circuit.

Both ends of the sixth resistor R6 are respectively connected to the non-inverting input terminal of the operational amplifier OP1 and the inverting input terminal of the operational amplifier OP1.

When the switching circuit is on, power is supplied to the load. In this case, a current flows through the sixth resistor R6, and a voltage difference is generated across the sixth resistor R6. And two ends of the sixth resistor R6 are respectively connected with the non-inverting input end and the inverting input end of the operational amplifier OP1, the voltage difference between the two ends of the sixth resistor R6 is amplified by the operational amplifier OP1, and then the amplified voltage is sent to the first input end of the controller.

Parameters of the sixth resistor R6 and parameters of the operational amplifier OP1 may be preconfigured in the controller. After the first input terminal of the controller receives the voltage value sent by the operational amplifier OP1, the controller may calculate the current passing through the sixth resistor R6 according to the voltage value, the parameter of the sixth resistor R6 and the parameter of the operational amplifier OP1, and further calculate the energy according to the current. And then comparing the energy with a pre-configured energy threshold value to judge whether the switching circuit needs to be disconnected.

In one embodiment, as shown in fig. 3, a first end of the sixth resistor R6 is connected to the power input end, and a second end of the sixth resistor R6 is connected to the source of the PMOS transistor Q1. The two ends of the sixth resistor R6 are respectively connected with the non-inverting input end of the operational amplifier OP1 and the input end of the operational amplifier OP1, and the output end of the operational amplifier OP1 is connected with the first input end of the controller.

In another embodiment, as shown in fig. 4, a first end of the sixth resistor R6 is connected to the drain of the PMOS transistor Q1, and a second end of the sixth resistor R6 is connected to the power output terminal. The two ends of the sixth resistor R6 are respectively connected with the non-inverting input end of the operational amplifier OP1 and the input end of the operational amplifier OP1, and the output end of the operational amplifier OP1 is connected with the first input end of the controller.

In this embodiment, as shown in fig. 3 and 4, the safety circuit further includes a diode D1, where a cathode of the diode D1 is connected to the power output terminal, and an anode of the diode D1 is grounded.

The power output end is connected with the load through a wire harness and is used for supplying power to the load. When the load is suddenly powered off, negative voltage up to hundreds of volts can be accumulated at the output end of the power supply instantaneously, and the PMOS tube Q1 can be damaged under the condition. The power output end is connected with a diode D1, the cathode of the diode D1 is connected with the power output end, and the anode of the diode D1 is grounded. When the negative voltage occurs at the power output end, the diode D1 is turned on, and the voltage at the power output end is clamped in a small range due to the smaller turn-on voltage of the diode D1. For example, the turn-on voltage of the diode D1 is 0.7V, because the positive electrode of the diode D1 is grounded, that is, the positive electrode of the diode D1 is 0V, when the diode D1 is turned on, the negative electrode of the diode D1 is-0.7V, that is, the voltage of the power output terminal is clamped to-0.7V.

According to the embodiment, the diode D1 is arranged at the power output end, the voltage of the power output end is limited in a small range through the diode D1, the negative pressure generated when the load is suddenly powered off is prevented from damaging the PMOS tube Q1, and the service life of the safety circuit is prolonged.

In this embodiment, the protection circuit further includes a first filter capacitor C1 and a second filter capacitor C2. The first end of the first filter capacitor C1 is connected with the power supply output end, and the second end of the first filter capacitor C1 is grounded. The first end of the second filter capacitor C2 is connected with the power input end, and the second end of the second filter capacitor C2 is grounded.

This embodiment describes an electronic safety device including a safety circuit as described in any of the embodiments of the present application.

This embodiment describes a vehicle having the electronic safe described in the above embodiment. The vehicle-mounted power supply of the vehicle is connected with the power input end of the electronic safety device, and the power output end of the electronic safety device is connected with the load of the vehicle. When the load is suddenly powered off, the electronic safety device is disconnected to stop power supply.

The methods in this application may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer program or instructions are loaded and executed on a computer, the processes or functions described herein are performed in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, a network device, a user device, a core network device, an OAM, or other programmable apparatus.

The computer programs/instructions described herein may be downloaded from a computer readable storage medium to the individual computing/processing devices or to an external computer or external storage device via a network, such as the internet, a local area network, a wide area network, and/or a wireless network. The network may include copper transmission cables, fiber optic transmissions, wireless transmissions, routers, firewalls, switches, gateway computers and/or edge servers. The network interface card or network interface in each computing/processing device receives computer readable program instructions from the network and forwards the computer readable program instructions for storage in a computer readable storage medium in the respective computing/processing device.

Computer program instructions for carrying out operations of the present utility model may be assembly instructions, instruction Set Architecture (ISA) instructions, machine-related instructions, microcode, firmware instructions, state setting data, or source or object code written in any combination of one or more programming languages, including an object oriented programming language such as Smalltalk, c++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The computer readable program instructions may be executed entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any kind of network, including a Local Area Network (LAN) or a Wide Area Network (WAN), or may be connected to an external computer (for example, through the Internet using an Internet service provider). In some embodiments, aspects of the present utility model are implemented by personalizing electronic circuitry, such as programmable logic circuitry, field Programmable Gate Arrays (FPGAs), or Programmable Logic Arrays (PLAs), with state information for computer readable program instructions, which can execute the computer readable program instructions.

Various aspects of the present utility model are described herein with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the utility model. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer-readable program instructions.

These computer readable program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks. These computer readable program instructions may also be stored in a computer readable storage medium that can direct a computer, programmable data processing apparatus, and/or other devices to function in a particular manner, such that the computer readable medium having the instructions stored therein includes an article of manufacture including instructions which implement the function/act specified in the flowchart and/or block diagram block or blocks.

The computer readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other devices to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the instructions which execute on the computer, other programmable apparatus or other devices implement the functions/acts specified in the flowchart and/or block diagram block or blocks.

The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present utility model. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of instructions, which comprises one or more executable instructions for implementing the specified logical function(s). In some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions. It is well known to those skilled in the art that implementation by hardware, implementation by software, and implementation by a combination of software and hardware are all equivalent.

The foregoing description of embodiments of the utility model has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the various embodiments described. The terminology used herein was chosen in order to best explain the principles of the embodiments, the practical application, or the technical improvement of the technology in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein. The scope of the utility model is defined by the appended claims.

Claims

1. The safety circuit is characterized by comprising a current detection circuit, a switching circuit, a controller, a power input end and a power output end which are separately arranged on a circuit board;

2. The safety circuit of claim 1, wherein a first terminal of the current detection circuit is connected to the power input terminal, a second terminal of the current detection circuit is connected to a first terminal of the switching circuit, and a second terminal of the switching circuit is connected to the power output terminal.

3. The safety circuit of claim 1, wherein a first terminal of the switching circuit is connected to the power supply input terminal, a second terminal of the switching circuit is connected to a first terminal of the current detection circuit, and a second terminal of the current detection circuit is connected to the power supply output terminal.

4. A safety circuit according to claim 2 or 3, wherein the switching circuit comprises a PMOS transistor Q1 and an NMOS transistor Q2;

the source of the PMOS tube Q1 is a first end of the switch circuit, the drain of the PMOS tube Q1 is a second end of the switch circuit, and the gate of the NMOS tube Q2 is a control end of the switch circuit;

5. The safety circuit according to claim 4, further comprising a temperature detection circuit for detecting the temperature of the PMOS transistor Q1, an output of the temperature detection circuit being connected to the second input of the controller;

6. The safety circuit according to claim 5, wherein the temperature detection circuit comprises a fourth resistor R4 and a fifth resistor R5, the fourth resistor R4 is a thermistor, and the fourth resistor R4 is configured to be attached to the surface of the PMOS transistor Q1;

7. A safety circuit according to claim 2 or 3, wherein the current detection circuit comprises a sixth resistor R6 and an operational amplifier OP1;

the two ends of the sixth resistor R6 are a first end of the current detection circuit and a second end of the current detection circuit, and the output end of the operational amplifier OP1 is the output end of the current detection circuit;

8. The safety circuit according to claim 1, further comprising a diode D1, wherein a negative electrode of the diode D1 is connected to the power output terminal, and wherein a positive electrode of the diode D1 is grounded.

9. The safety circuit according to claim 1, further comprising a first filter capacitor C1 and a second filter capacitor C2;

the first end of the first filter capacitor C1 is connected with the power supply output end, and the second end of the first filter capacitor C1 is grounded;

the first end of the second filter capacitor C2 is connected with the power input end, and the second end of the second filter capacitor C2 is grounded.

10. An electronic safety device comprising the safety circuit of any one of claims 1-9.

11. A vehicle having the electronic safe of claim 10.