CN220964313U

CN220964313U - Detection protection circuit, switch circuit and vehicle

Info

Publication number: CN220964313U
Application number: CN202322550673.1U
Authority: CN
Inventors: 武保东; 邵可可; 杜恩利
Original assignee: Hefei Yangguang Electric Power Technology Co ltd
Current assignee: Hefei Yangguang Electric Power Technology Co ltd
Priority date: 2023-09-19
Filing date: 2023-09-19
Publication date: 2024-05-14
Anticipated expiration: 2033-09-19

Abstract

The utility model discloses a detection protection circuit, a switch circuit and a vehicle. The detection protection circuit includes: the detection module is used for detecting whether the current flowing through the target switch is greater than a preset threshold value or not and outputting a detection result; the latch module outputs level voltage according to the detection result; the protection switch is used for controlling the disconnection of the target switch according to the level voltage; under the condition that the current is larger than a preset threshold value, the detection result is a first detection result, and the latch module enters a latch state according to the first detection result and outputs a first level voltage so as to enable the protection switch to be on, thereby controlling the target switch to be off. When the current is larger than a preset threshold value, the detection module outputs a first detection result, and the latching module enters a latching state according to the received first detection result and continuously outputs a first level voltage so as to conduct the protection switch, thereby controlling the disconnection of the target switch and realizing the overcurrent protection of the target switch.

Description

Detection protection circuit, switch circuit and vehicle

Technical Field

The utility model relates to the technical field of overcurrent detection protection, in particular to a detection protection circuit, a switch circuit and a vehicle.

Background

The low-side driving is realized by closing the ground wire to realize the driving mode of the driving device for enabling the driving, the realization mode is easier, and the circuit structure is simpler. In the related art, components with higher specifications are required to be selected to avoid overcurrent damage, and the requirements on the components are strict.

Disclosure of utility model

The embodiment of the utility model provides a detection protection circuit, a switching circuit and an energy storage system.

The embodiment of the utility model provides a detection protection circuit, which comprises a detection module, a latch module and a protection switch, wherein the detection module is used for detecting whether the current flowing through a target switch is greater than a preset threshold value or not and outputting a detection result; the latch module is used for outputting level voltage according to the detection result; the protection switch is used for controlling the disconnection of the target switch according to the level voltage; and under the condition that the current is larger than a preset threshold value, the detection result is a first detection result, the latch module is used for entering and maintaining a latch state according to the first detection result, and when the latch module is in the latch state, the latch module is used for outputting a first level voltage so as to enable the protection switch to be conducted, and the protection switch is used for controlling the target switch to be disconnected.

In some embodiments, the detection module is configured to output a second detection result when the current is lower than the preset threshold, and the latch module is configured to output a second level voltage according to the second detection result, so that the protection switch is turned off.

In some embodiments, the detection module includes a sampling resistor for sampling the current to obtain a detection voltage, the detection voltage being a voltage across the sampling resistor.

In some embodiments, the detection module includes a comparator for outputting the detection result according to a comparison result of the detection voltage and a reference voltage, the reference voltage being determined according to the preset threshold.

In some embodiments, the detection module further includes an input module, where the input module includes a first voltage dividing resistor and a second voltage dividing resistor connected in series, and the reference voltage is obtained by dividing the reference voltage by the first voltage dividing resistor and the second voltage dividing resistor.

In some embodiments, the comparator includes a first input terminal for inputting the reference voltage and a second input terminal for inputting the detection voltage, and an output terminal of the comparator is for outputting the detection result.

In some embodiments, when the latch module is in the latch state and the target switch is turned off, if the current is smaller than the preset threshold, the detection module is configured to output a second detection result, and the latch module is configured to output a first level voltage according to the latch state, so as to control the protection switch to be turned on. In some embodiments, the detection protection circuit further includes a control module, where the control module is connected to the latch module, and when the detection module outputs the first detection result, the latch module is configured to output a fault signal to the control module, and the control module is configured to determine a fault type according to the fault signal.

In some embodiments, the control module is configured to output a control signal according to the fault type, the latch module is configured to clear the latch state according to the control signal, and in a case where the latch state is cleared, the latch module is configured to be capable of outputting a second level voltage, where the second level voltage is configured to control the protection switch to be turned off.

The embodiment of the utility model provides a switch circuit, which comprises a target switch and the detection protection circuit of any embodiment, wherein the detection protection circuit is used for carrying out overcurrent protection on the target switch.

An embodiment of the present utility model provides a vehicle including a vehicle body and the switch circuit of the above embodiment, the switch circuit being disposed in the vehicle body.

In the detection protection circuit, the switch circuit and the energy storage system of the embodiment of the utility model, when the current is larger than the preset threshold value, the detection module outputs the first detection result, the latch module enters the latch state according to the received first detection result and continuously outputs the first level voltage, so that the protection switch is turned on, the target switch is controlled to be turned off, overcurrent protection on the target switch is realized, and after the target switch is turned off, the latch module still maintains the latch state and continuously outputs the first level voltage, so that the target switch is ensured to be continuously in the off state, the target switch can be effectively protected, and overheating damage of the target switch can be avoided without selecting elements with higher specifications.

Additional aspects and advantages of the utility model will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the utility model.

Drawings

The foregoing and/or additional aspects and advantages of the present utility model will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings, in which:

fig. 1 is a schematic circuit diagram of a detection protection circuit according to an embodiment of the present utility model;

FIG. 2 is a schematic diagram of the connection of a latch module and a control module according to an embodiment of the present utility model;

fig. 3 is a circuit schematic of a test protection circuit and a load according to an embodiment of the present utility model.

Detailed Description

Embodiments of the present utility model are described in detail below, and are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary only for explaining the present utility model and are not to be construed as limiting the present utility model.

With the development of new energy electric vehicles, more and more electromagnetic valve bodies (or pump bodies) are applied to the automobile industry. In the whole automobile system, the electromagnetic valve bodies are generally applied to gear control of a gearbox, valve body current needs to be precisely controlled, and a low-side driving circuit is used as a driving mode in a plurality of driving designs. The low-side driving is a driving mode for realizing the driving of the driving device by closing the ground wire, the implementation mode is easier, and the circuit structure is simpler. In the related art, components with higher specifications are required to be selected to avoid overcurrent damage, and the requirements on the components are strict.

Referring to fig. 1, an embodiment of the present utility model provides a detection protection circuit 100, where the detection protection circuit 100 includes a detection module 10, a latch module 30, and a protection switch 50, and the detection module 10 is configured to detect whether a current flowing through a target switch 200 is greater than a preset threshold value, and output a detection result; the latch module 30 is used for outputting a level voltage according to the detection result; the protection switch 50 is used for controlling the opening of the target switch 200 according to the level voltage; under the condition that the current is greater than the preset threshold, the detection result is a first detection result, the latch module 30 is configured to enter and maintain a latch state according to the first detection result, and when the latch module 30 is in the latch state, the latch module 30 is configured to output a first level voltage, so that the protection switch 50 is turned on, and the protection switch 50 is configured to control the target switch 200 to be turned off.

Specifically, the target switch 200 includes a low-side driving switch for implementing a low-side driving mode, where the low-side driving switch may be a P-type MOS, and the target switch 200 may also be an N-type MOS, in this embodiment, the target switch 200 is illustrated by using an N-type MOS as the target switch 200, Q2 may represent the low-side driving switch, the detection protection circuit 100 may detect a current flowing through the low-side driving switch Q2, and when the current exceeds a preset threshold, the low-side driving switch Q2 is controlled to be turned off, so as to implement overcurrent protection on the low-side driving switch Q2. V _G in fig. 1 is used to represent a gate control voltage, and the gate control voltage V _G is used to control on-off of the target switch 200, and when the gate control voltage V _G is at a low level, the target switch 200 is turned off; when the gate control voltage V _G is at a high level, the target switch 200 is turned on. The protection switch 50 may be a P-type MOS transistor, and the protection switch 50 may also be an N-type MOS transistor, and in this embodiment, the protection switch 50 is illustrated as a P-type MOS transistor. The first level voltage may be a low level, the latch module 30 includes a latch U2, the latch U2 is connected to the gate of the protection switch 50, and the protection switch 50 is turned on when the latch U2 outputs the low level. The detection module 10 is connected with the low-side driving switch Q2, detects the current flowing through the low-side driving switch Q2, determines whether the current exceeds a preset threshold, and outputs a first detection result when the current flowing through the low-side driving switch Q2 exceeds the preset threshold; the latch U2 is connected with the detection module 10 and the protection switch 50, when the latch U2 receives a first detection result output by the detection module 10, the latch U2 enters and maintains a latch state, and when the latch U2 is in the latch state, the latch U2 outputs a first level voltage to control the protection switch 50 to be closed; one end of the protection switch 50 is grounded, the other end of the protection switch 50 is connected with the grid electrode of the low-side driving switch Q2, when the protection switch 50 is closed, the grid electrode voltage of the low-side driving switch Q2 is pulled down, and the low-side driving switch Q2 is disconnected, so that overcurrent protection on the low-side driving switch Q2 is realized.

In this way, when the current is greater than the preset threshold, the detection module 10 outputs the first detection result, the latch module 30 enters the latch state according to the received first detection result and continuously outputs the first level voltage, so that the protection switch 50 is turned on, thereby controlling the target switch 200 to be turned off, and the overcurrent protection of the target switch 200 is achieved, and after the target switch 200 is turned off, the latch module 30 still maintains the latch state and continuously outputs the first level voltage, so as to ensure that the target switch 200 is continuously in the off state, so that the target switch 200 can be effectively protected, and overheat damage of the target switch 200 can be avoided without selecting a component with a higher specification.

In some embodiments, in the case that the current is lower than the preset threshold, the detection module 10 is configured to output a second detection result, and the latch module 30 is configured to output a second level voltage according to the second detection result, so that the protection switch 50 is turned off.

Specifically, the second level voltage may be a high level, and when the current flowing through the low-side driving switch Q2 is lower than the preset threshold, the detection module 10 outputs a second detection result, if the latch U2 is not in the latch state, the latch U2 outputs the second level voltage according to the second detection result, that is, outputs the high level, the voltage of the gate of the protection switch 50 is pulled high, the protection switch 50 is turned off, and the low-side driving switch Q2 can be normally turned on or off according to the gate control voltage V _G, so that the detection protection circuit 100 can control the low-side driving switch Q2 to be normally turned on or off according to the gate control voltage V _G when the low-side driving switch Q2 is in the normal working state, that is, when the low-side driving switch Q2 does not have an overcurrent or a short circuit, and the like, so as to ensure the normal working of the low-side driving switch Q2.

In this way, the latch module 30 may output a level voltage according to the detection result output by the detection module 10, so as to control the on/off of the protection switch 50, thereby controlling the on of the low-side driving switch Q2, and when outputting the second level voltage, the protection switch 50 is turned off, so that the on state of the low-side driving switch Q2 is not affected, and the low-side driving switch Q2 can be normally turned on or off.

In some embodiments, the detection module 10 includes a sampling resistor 11, where the sampling resistor 11 is used to sample a current to obtain a detection voltage, and the detection voltage is a voltage across the sampling resistor 11.

Specifically, referring to fig. 1, R8 is a sampling resistor 11, one end of the sampling resistor 11 is connected to the low-side driving switch Q2, the other end of the sampling resistor 11 is grounded, the current flowing through the sampling resistor 11 is the current flowing through the low-side driving switch Q2, and the voltage of the sampling resistor 11 can be obtained according to the resistance of the sampling resistor 11 and the current flowing through the sampling resistor 11, so as to obtain the detection voltage. The voltage value of the detection voltage is the product of the resistance value of the sampling resistor 11 and the current value flowing through the sampling resistor 11, so that the voltage value of the detection voltage is in direct proportion to the current flowing through the low-side driving switch Q2, and when the current flowing through the low-side driving switch Q2 increases, the detection voltage increases; as the current flowing through the low-side drive switch Q2 decreases, the detection voltage decreases.

In this way, the sampling resistor 11 can obtain the detection voltage according to the current flowing through the target switch 200, the detection voltage is proportional to the current flowing through the target switch 200, and the change condition of the current flowing through the target switch 200 can be determined according to the detection voltage.

In some embodiments, the detection module 10 includes a comparator 13, where the comparator 13 is configured to output a detection result according to a comparison result between the detection voltage and a reference voltage, and the reference voltage is determined according to a preset threshold.

Specifically, since the detection voltage is proportional to the current flowing through the low-side driving switch Q2, the change condition of the current flowing through the target switch 200 can be determined from the detection voltage. The reference voltage is determined according to the preset threshold value, and then the comparison result of the current flowing through the low-side driving switch Q2 and the preset threshold value can be determined according to the comparison result of the detection voltage and the reference voltage. When the detected voltage is greater than the reference voltage, the current flowing through the low-side driving switch Q2 is considered to be greater than the preset threshold; when the detected voltage is smaller than the reference voltage, the current flowing through the low-side driving switch Q2 is considered to be smaller than the preset threshold. The detection module 10 outputs a detection result according to the comparison result, and when the detection voltage is greater than the reference voltage, namely, when the current flowing through the low-side drive switch Q2 is greater than a preset threshold value, the detection module 10 outputs a first detection result; when the detection voltage is smaller than the reference voltage, that is, when the current flowing through the low-side driving switch Q2 is smaller than the preset threshold, the detection module 10 outputs a second detection result.

Thus, by determining the reference voltage according to the preset threshold value, the comparison result of the current flowing through the target switch 200 and the preset threshold value can be obtained according to the comparison result of the detection voltage and the reference voltage, the detection module 10 outputs the detection result according to the comparison result, the latch module 30 outputs the level voltage according to the received detection result, so as to control the on-off of the protection switch 50, and when the protection switch 50 is turned off, the target switch 200 can be turned on-off according to the gate control signal V _G; when the protection switch 50 is on, the target switch 200 is off.

Referring to fig. 1, in some embodiments, the detection module 10 further includes an input module 15, where the input module 15 includes a first voltage dividing resistor and a second voltage dividing resistor connected in series, and the reference voltage is obtained by dividing the reference voltage by the first voltage dividing resistor and the second voltage dividing resistor.

Specifically, the input module 15 is connected to the input end of the comparator 13, and the resistance values of the first voltage dividing resistor and the second voltage dividing resistor can be changed according to actual requirements, so as to obtain a suitable reference voltage, and the magnitude of the reference voltage is determined according to a preset threshold value. In one embodiment, R4 is used to represent a first voltage dividing resistor, R5 is used to represent a second voltage dividing resistor, one end of the first voltage dividing resistor R4 is connected to one end of the second voltage dividing resistor R5 and an input end of the comparator 13, the other end of the first voltage dividing resistor R4 is grounded, the other end of the second voltage dividing resistor R5 is connected to a preset voltage source, the voltage of the preset voltage source is 5V, and the reference voltage is the voltage of the first voltage dividing resistor R4.

In this way, the reference voltage may be obtained according to the first voltage dividing resistor and the second voltage dividing resistor of the input module 15, the reference voltage may be determined according to the preset threshold value, and the comparison result of the current flowing through the target switch 200 and the preset threshold value may be obtained according to the comparison result of the reference voltage and the detection voltage.

In some embodiments, the comparator 13 includes a first input terminal for inputting the reference voltage, and a second input terminal for inputting the detection voltage, and an output terminal of the comparator 13 is for outputting the detection result.

Specifically, the input terminals of the comparator 13 include a non-inverting input terminal and an inverting input terminal, the first input terminal may be the non-inverting input terminal of the comparator 13, and the second input terminal may be the inverting input terminal of the comparator 13. Of course, in other embodiments, the first input terminal may be an inverting input terminal of the comparator 13, and the second input terminal may be a non-inverting input terminal of the comparator 13, which is not limited herein. The non-inverting input end of the comparator 13 is connected with one end of a first voltage dividing resistor of the input module 15 and one end of a second voltage dividing resistor, the other end of the first voltage dividing resistor is grounded, the other end of the second voltage dividing resistor is connected with a preset voltage source, the reference voltage is the voltage of the first voltage dividing resistor, and the reference voltage is input into the non-inverting input end of the comparator 13. The inverting input terminal of the comparator 13 is connected to one end of the sampling resistor 11, the voltage of the sampling resistor 11 is the detection voltage, and the detection voltage is input to the inverting input terminal of the comparator 13. The output end of the comparator 13 is connected with the reset end R of the latch U2, the output end of the comparator 13 outputs a detection result, the input voltage of the non-inverting input end of the comparator 13 is larger than the input voltage of the inverting input end of the comparator 13, and the output end of the comparator 13 outputs a high level to output a second detection result; when the input voltage of the non-inverting input terminal of the comparator 13 is smaller than the input voltage of the inverting input terminal of the comparator 13, that is, when the reference voltage is smaller than the preset voltage, the output terminal of the comparator 13 outputs a low level to output the first detection result.

In this way, the comparator 13 compares the reference voltage input by the first input end with the detection voltage input by the second input end, and outputs a detection result according to the comparison result, and when the reference voltage is greater than the detection voltage, the output end of the comparator 13 outputs a second detection result; when the reference voltage is smaller than the detection voltage, the output terminal of the comparator 13 outputs a first detection result.

In some embodiments, when the latch module 30 is in the latch state and the target switch 200 is turned off, the current is less than the preset threshold, the detection module 10 is configured to output the second detection result, and the latch module 30 is configured to output the first level voltage according to the latch state, so as to control the protection switch 50 to be capable of being turned on.

Specifically, the latch U2 outputs a level voltage according to the detection result received by the reset terminal R and whether the latch U2 is in the latch state, and when the latch U2 is not in the latch state, the reset terminal R receives the first detection result, the latch U2 enters the latch state, and outputs the first level voltage; when the latch U2 is not in the latch state, the reset end R receives a second detection result, and the latch U2 outputs a second level voltage; when the latch U2 is in the latch state, the reset terminal R receives the first detection result or the second detection result, and the latch U2 outputs the first level voltage. When the latch U2 outputs the first level voltage, that is, the latch U2 outputs the low level, the gate voltage of the protection switch 50 is pulled down, the P-type MOS transistor Q1 serving as the protection switch 50 is turned on, the gate voltage of the low-side driving switch Q2 is pulled down, and the low-side driving switch Q2 is turned off; when the latch U2 outputs the second level voltage, that is, the latch U2 outputs the high level, the gate voltage of the protection switch 50 is pulled up, the P-type MOS transistor Q1 serving as the protection switch 50 is turned off, the gate voltage of the low side driving switch Q2 is pulled up, and the low side driving switch Q2 can be turned on. Under the condition that the latch U2 is in the latch state and the target switch 200 is turned off, the current flowing through the target switch 200 is smaller than the preset threshold, and the output end of the comparator 13 outputs the second detection result, but since the latch U2 is in the latch state, the latch U2 outputs the first level voltage, so that the P-type MOS transistor Q1 as the protection switch 50 is turned on, and the low-side driving switch Q2 is turned off.

In this way, when the latch is in the latch state, the first level voltage is continuously output, and the protection switch 50 is turned on to control the low-side driving switch to be turned off, so as to realize continuous protection of the low-side driving switch.

Referring to fig. 2, in some embodiments, the detection protection circuit 100 further includes a control module 70, where the control module 70 is connected to the latch module 30, and in a case that the detection module 10 outputs the first detection result, the latch module 30 is configured to output a fault signal to the control module 70, and the control module 70 is configured to determine a fault type according to the fault signal.

Specifically, the control module 70 includes a single-chip microcomputer and an MCU, and in this embodiment, the control module 70 is illustrated as the MCU. The MCU is connected with the output end Q of the latch U2, and when the latch U2 outputs the first level voltage, the first level voltage is input into the MCU as a fault signal. And when the MCU receives the first level voltage, the MCU analyzes the fault type. The fault type includes a first fault and a second fault, the first fault is used for indicating that the target switch 200 can be turned on, and the fault can be removed after the target switch is turned on; the second fault is used to indicate that the target switch 200 is permanently faulty, and if the target switch 200 is still over-current after being turned on, the possibility of over-current fault still exists. When the MCU determines that the fault type is a first fault, the MCU controls the latch U2 to clear the latch state; when the MCU determines that the fault type is the second fault, the MCU controls the latch U2 to maintain the latch state.

In this manner, the control module 70 may determine the fault type according to the fault signal, so as to control the latch module 30 according to the fault type, to achieve protection of the target switch 200.

In some embodiments, the control module 70 is configured to output a control signal according to the fault type, the latch module 30 is configured to clear the latch state according to the control signal, and in the case of clearing the latch state, the latch module 30 is configured to be capable of outputting a second level voltage, where the second level voltage is configured to control the protection switch 50 to be turned off.

Specifically, the latch U2 includes a set terminal S and a reset terminal R, the MCU is connected to the set terminal S of the latch U2, and when the set terminal S inputs a high level and the latch U2 is not in a latch state, if the reset terminal R inputs a high level, the output terminal Q outputs a high level; if the reset terminal R inputs low level, the latch U2 enters a latch state, and the output terminal Q outputs low level; if the latch U2 is in a latch state and the set end S inputs a high level, the reset end R inputs a high level or a low level, and the output end Q outputs a low level; if the latch U2 is in the latch state, the set terminal S inputs a low level, and the latch U2 clears the latch state. When the MCU determines that the fault type is the first type, the MCU outputs a low level to the set terminal S of the latch U2 as a control signal, so that the latch U2 clears the latch state, and if the current flowing through the low-side driving switch Q2 is smaller than the preset threshold, that is, the detection voltage is smaller than the reference voltage, the comparator 13 outputs a high level to indicate the second detection result, the reset terminal R of the latch receives the high level, the output terminal Q of the latch outputs the high level, and the protection switch 50 is turned off, so that the low-side driving switch Q2 can be turned on or off according to the gate control signal V _G.

In this manner, the control module 70 outputs the control signal, so that the latch can output the second level voltage, and the protection switch 50 is turned off, so that the control target switch 200 can be normally turned on or off.

Referring to fig. 1, in some embodiments, the detection protection circuit 100 further includes a filtering module 90, where the filtering module includes a filtering resistor and a filtering capacitor, and the filtering module 90 is configured to filter the detection voltage.

Specifically, R6 may represent a filter resistor, C1 may represent a filter capacitor, one end of the filter resistor R6 is connected to one end of the sampling resistor 11, and the other end of the filter resistor R6 is connected to one end of the filter capacitor C1 and the second input end of the comparator; the other end of the filter capacitor C1 is grounded. The filter resistor R6 and the filter capacitor C1 form an RC low-pass filter circuit, which can remove high-frequency signals in the detection voltage and prevent the occurrence of error of the comparator caused by interference signals, thereby being convenient for the comparator to accurately compare the detection voltage with the reference voltage.

Therefore, the detection voltage can be filtered by setting the filter resistor and the filter capacitor, so that the occurrence of errors of the comparator caused by interference signals is prevented.

The embodiment of the utility model provides a switch circuit, which comprises a target switch 200 and the detection protection circuit 100 of any embodiment, wherein the detection protection circuit 100 is used for performing overcurrent protection on the target switch 200.

Referring to fig. 3, an embodiment of the present utility model provides a vehicle, including a vehicle body and the switch circuit of the above embodiment, where the switch circuit is disposed in the vehicle body.

Specifically, the vehicle further includes a load 300, the load 300 includes a solenoid valve or a water pump, M in fig. 3 is used to represent the load 300, one end (V _L) of the load 300 is connected to the drain (V _D) of the low-side driving switch Q2, and the other end of the load 300 is connected to a power source (DC). In addition, the resistor R1 in fig. 3 is used to limit the gate current of the low-side driving switch Q2 to delay the on and off of the low-side driving switch Q2. Because the drain electrode (V _D) of the low-side driving switch Q2 is easy to cause a short circuit to the power supply DC due to the reason of aging of the wire harness, the low-side driving switch Q2 may be damaged due to large current impact at the conducting moment of the low-side driving switch Q2, so the detection protection circuit 100 is configured to perform overcurrent protection on the low-side driving switch Q2, so that when the current flowing through the low-side driving switch Q2 exceeds a preset threshold value, the low-side driving switch Q2 is controlled to be turned off, so that the low-side driving switch Q2 is prevented from being damaged by the large current impact.

In the description of the present specification, reference is made to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., meaning that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the utility model. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. 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.

Furthermore, the term "coupled" is to be broadly interpreted and includes, for example, either permanently coupled, detachably coupled, or integrally coupled; can include direct connection, indirect connection through intermediate media, and communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are 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 the description of the present utility model, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

Any process or method descriptions in flow charts or otherwise described herein may be understood as representing modules, segments, or portions of code which include one or more executable instructions for implementing specific logical functions or steps of the process, and further implementations are included within the scope of the preferred embodiment of the present utility model in which functions may be executed out of order from that shown or discussed, including substantially concurrently or in reverse order from that shown or discussed, depending on the functionality involved, as would be understood by those reasonably skilled in the art of the embodiments of the present utility model.

While embodiments of the present utility model have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the utility model, and that variations, modifications, alternatives and variations may be made to the above embodiments by one of ordinary skill in the art within the scope of the utility model.

Claims

1. A detection protection circuit for a target switch, the detection protection circuit comprising:

The detection module is used for detecting whether the current flowing through the target switch is larger than a preset threshold value or not and outputting a detection result;

The latch module is used for outputting level voltage according to the detection result;

The protection switch is used for controlling the disconnection of the target switch according to the level voltage;

And under the condition that the current is larger than a preset threshold value, the detection result is a first detection result, the latch module is used for entering and maintaining a latch state according to the first detection result, and when the latch module is in the latch state, the latch module is used for outputting a first level voltage so as to enable the protection switch to be conducted, and the protection switch is used for controlling the target switch to be disconnected.

2. The detection protection circuit according to claim 1, wherein the detection module is configured to output a second detection result, and the latch module is configured to output a second level voltage according to the second detection result, so that the protection switch is turned off, in a case where the current is lower than the preset threshold.

3. The protection circuit of claim 1, wherein the detection module comprises a sampling resistor for sampling the current to obtain a detection voltage, the detection voltage being a voltage across the sampling resistor.

4. A detection protection circuit according to claim 3, wherein the detection module comprises a comparator for outputting the detection result based on a comparison result of the detection voltage and a reference voltage, the reference voltage being determined based on the preset threshold value.

5. The protection circuit of claim 4, wherein the detection module further comprises an input module comprising a first voltage dividing resistor and a second voltage dividing resistor connected in series, the reference voltage being divided by the first voltage dividing resistor and the second voltage dividing resistor.

6. The protection circuit according to claim 4, wherein the comparator includes a first input terminal for inputting the reference voltage and a second input terminal for inputting the detection voltage, and an output terminal of the comparator is for outputting the detection result.

7. The detection protection circuit according to claim 1, wherein, when the latch module is in the latch state and the target switch is turned off, if the current is smaller than the preset threshold, the detection module is configured to output a second detection result, and the latch module is configured to output a first level voltage according to the latch state, so as to control the protection switch to be turned on.

8. The detection and protection circuit according to claim 1, further comprising a control module connected to the latch module, wherein the latch module is configured to output a fault signal to the control module when the detection module outputs the first detection result, and the control module is configured to determine a fault type according to the fault signal.

9. The protection circuit according to claim 8, wherein the control module is configured to output a control signal according to the fault type, the latch module is configured to clear the latch state according to the control signal, and the latch module is configured to be capable of outputting a second level voltage when the latch state is cleared, the second level voltage being configured to control the protection switch to be turned off.

10. A switching circuit comprising a target switch and the detection protection circuit of any one of claims 1-9 for over-current protection of the target switch.

11. A vehicle comprising a vehicle body and the switch circuit of claim 10, the switch circuit disposed within the vehicle body.