CN220983436U - Circuit detection circuit and device - Google Patents

Abstract

The present application relates to the field of line detection technology, and discloses a line detection circuit and device, the circuit comprising: a power supply module, a voltage divider circuit, a detection display circuit, a connection plug-in interface and a detection switch; the power supply module is respectively connected to the voltage divider circuit and the detection display circuit, the connection plug-in interface is respectively connected to the voltage divider circuit, the detection display circuit, the first end of the detection switch and the output interface of the line to be detected, and the second end of the detection switch is connected to the system power ground; the voltage divider circuit is used to divide the input voltage provided by the power supply module to obtain a divided voltage when the line detection circuit is turned on, and the detection display circuit is used to detect and display based on the divided voltage to realize line detection; wherein, the line detection circuit is turned on including the first end of the detection switch being connected to the second end of the detection switch, and the line to be detected is turned on. The present application reduces the cost of line rectification difficulty.

Description

Line detection circuit and device

Technical Field

The utility model relates to the technical field of line detection, in particular to a line detection circuit and a device.

Background technique

With the development of CAN (Controller Area Network) communication technology, users' requirements for CAN line detection have also increased.

The traditional line detection method is to use a voltmeter to detect the terminal resistance installation and wiring harness connection in the line after the line is laid. This line detection method has a big defect, and there is a problem that the detection can only be performed after the line is laid. That is, this line detection method will make it difficult to rectify the line because it needs to be detected after the line is laid. Therefore, a new line detection circuit is urgently needed to detect the line, thereby reducing the difficulty of line rectification.

Utility Model Content

The main purpose of the utility model is to propose a line detection circuit and a device, aiming at providing a line detection circuit to detect the line, thereby reducing the difficulty of line rectification.

To achieve the above object, the utility model provides a line detection circuit, which includes a power module, a voltage divider circuit, a detection display circuit, a connection plug-in interface and a detection switch;

The power module is connected to the voltage divider circuit and the detection and display circuit respectively, the connection plug-in interface is connected to the voltage divider circuit, the detection and display circuit, the first end of the detection switch and the output interface of the circuit to be detected respectively, and the second end of the detection switch is connected to the system power ground;

The voltage divider circuit is used to divide the input voltage provided by the power module to obtain a divided voltage when the line detection circuit is turned on, and the detection and display circuit is used to perform detection and display based on the divided voltage to achieve line detection; wherein, the line detection circuit is turned on including the first end of the detection switch being connected to the second end of the detection switch, and the line to be detected is turned on.

Optionally, the voltage-dividing circuit includes at least one voltage-dividing resistor connected in sequence, an input end of the voltage-dividing resistor is connected to the power module, and an input end of the voltage-dividing resistor is connected to the connection plug-in interface.

Optionally, the detection display circuit includes a buzzer and a detection indicator light, the power module is respectively connected to the input end of the buzzer and the input end of the detection indicator light, and the connection plug-in interface is respectively connected to the output end of the buzzer and the output end of the detection indicator light.

Optionally, the power module includes a battery, and an output end of the battery is connected to an input end of the voltage-dividing resistor, an input end of the buzzer, and an input end of the detection indicator light.

Optionally, the power module further includes a USB interface, which is respectively connected to an external charging device, an input end of a voltage divider resistor, an input end of the buzzer, and an input end of the detection indicator light.

Optionally, the detection switch comprises a four-pin push button switch, a first connecting pin of the four-pin push button switch is connected to the connection plug-in interface, and a second connecting pin of the four-pin push button switch is connected to the system power ground.

In addition, the present application also provides a line detection device, which includes a housing structure and a circuit board. The circuit board is provided with the above-mentioned line detection circuit, and the circuit board is provided in the housing structure.

Optionally, the housing structure includes an upper packaging housing and a lower housing, the circuit board is arranged on one side of the lower housing, and is packaged in a first box body formed by the upper packaging housing and the lower housing.

Optionally, a first through hole, a second through hole and a third through hole are set on the upper packaging plate of the upper packaging shell, and a fourth through hole and a fifth through hole are set on the side packaging plate of the upper packaging shell, the detection switch is set in the first through hole, the detection indicator light in the detection display circuit is set in the second through hole, the buzzer in the detection display circuit is set in the third through hole, the connection plug-in interface is set in the fourth through hole, and the USB interface in the power module is set in the fifth through hole, wherein the line detection device also includes a connecting wire, one end of the connecting wire is connected to the connecting plug-in interface, and the other end of the connecting wire is connected to the line detection circuit through the fourth through hole.

Optionally, the shell structure also includes a battery box, a battery and a battery cover, one side of the battery box is arranged on the other side of the lower shell, the battery is arranged in the battery box and connected to the line detection circuit, the battery cover is arranged on the other side of the battery box, and the battery box and the battery are encapsulated in a second box body composed of the upper encapsulation shell and the battery cover.

The present application provides a line detection circuit, which includes a power supply module, a voltage divider circuit, a detection display circuit, a connection plug-in interface and a detection switch; the power supply module is respectively connected to the voltage divider circuit and the detection display circuit, the connection plug-in interface is respectively connected to the voltage divider circuit, the detection display circuit, the first end of the detection switch and the output interface of the line to be detected, and the second end of the detection switch is connected to the system power ground; the voltage divider circuit is used to divide the input voltage provided by the power supply module to obtain a divided voltage when the line detection circuit is turned on, and the detection display circuit is used to perform detection and display based on the divided voltage to realize line detection; wherein, the line detection circuit is turned on including the first end of the detection switch being connected to the second end of the detection switch, and the line to be detected is turned on. When the first end of the detection switch is connected to the second end of the detection switch, and the line to be detected is turned on (it is not necessary to complete the laying), the detection is carried out by directly connecting the plug-in interface with the output interface of the line to be detected, and the input voltage provided by the power module is divided by the voltage divider circuit to obtain the divided voltage, and then the detection display of the detection display circuit can be determined based on the divided voltage, thereby avoiding the phenomenon in the prior art that the detection must be carried out after the line is laid, thereby causing high difficulty in line rectification. By connecting the first end of the detection switch with the second end of the detection switch, and when the line to be detected is turned on (it is not necessary to complete the laying), the detection is carried out by directly connecting the plug-in interface with the output interface of the line to be detected, and then the entire process can be carried out after the problem is detected. Since the laying is not completed at this time, the difficulty of line rectification can be reduced while the line is being detected.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the structure of a line detection circuit of the utility model;

FIG2 is a circuit connection diagram of a line detection circuit of the utility model;

FIG3 is another circuit connection diagram of the line detection circuit of the utility model;

FIG4 is a schematic diagram of a structure of a circuit detection device of the present utility model;

FIG. 5 is another schematic diagram of the structure of the circuit detection device of the present invention.

Description of Figure Numbers:

The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings.

Detailed ways

It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

It should be noted that all directional indications in the embodiments of the present application (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

In this application, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

In addition, in this application, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

In order to make the description of the following embodiments clear and concise, a brief introduction to a line detection method is first given:

The existing line detection method is to directly use specific circuit detection devices for detection after the entire circuit is established, such as ammeters and voltmeters. Take the detection of CAN lines in heavy-duty truck swap stations as an example. Because the electronic and electrical parts in heavy-duty truck swap stations use CAN communication, the wiring harness in the swap station will be laid in the container in advance during installation. After laying, there will be problems such as wiring harness disconnection and terminal resistance detection. If it is not detected in time, communication failure will occur after the parts are installed. At this time, the workload required to troubleshoot the fault is large. The current practice in the industry is that the wiring harness is laid and the parts are installed before the CAN communication harness function is normal. Therefore, the above detection methods at least have the problem of difficulty in detecting whether the CAN communication harness is installed properly and the CAN communication harness is found to have a function failure. The rectification workload is large and requires all-round rectification. However, the traditional voltmeter measurement has cumbersome operation steps and cannot guarantee the consistency of the operation of the workers. The above problems are explained in detail. For example, when installing a CAN line, it is impossible to determine whether the installation is qualified because there is no power during installation. Only when the installation is completed can we know whether it is qualified. The existing qualified detection method is to measure and determine it through a voltmeter. Because the voltmeter determines the method, the tester needs to have a clear specification for the value of the voltmeter. For example, different lengths of CAN lines correspond to different voltage values, which requires the tester to have experience in the entire detection specification. Based on the above problems, the line detection circuit of this application is proposed.

The present solution proposes a line detection circuit, which includes a power supply module, a voltage divider circuit, a detection display circuit, a connection plug-in interface and a detection switch; the power supply module is respectively connected to the voltage divider circuit and the detection display circuit, the connection plug-in interface is respectively connected to the voltage divider circuit, the detection display circuit, the first end of the detection switch and the output interface of the line to be detected, and the second end of the detection switch is connected to the system power ground; the voltage divider circuit is used to divide the input voltage provided by the power supply module to obtain a divided voltage when the line detection circuit is turned on, and the detection display circuit is used to perform detection and display based on the divided voltage to realize line detection; wherein, the line detection circuit is turned on including the first end of the detection switch being connected to the second end of the detection switch, and the line to be detected is turned on. When the first end of the detection switch is connected to the second end of the detection switch, and the line to be detected is turned on (it is not necessary to complete the laying), the detection is carried out by directly connecting the plug-in interface with the output interface of the line to be detected, and the input voltage provided by the power module is divided by the voltage divider circuit to obtain the divided voltage, and then the detection display of the detection display circuit can be determined based on the divided voltage, thereby avoiding the phenomenon in the prior art that the detection must be carried out after the line is laid, thereby causing high difficulty in line rectification. By connecting the first end of the detection switch with the second end of the detection switch, and when the line to be detected is turned on (it is not necessary to complete the laying), the detection is carried out by directly connecting the plug-in interface with the output interface of the line to be detected, and then the entire process can be carried out after the problem is detected. Since the laying is not completed at this time, the difficulty of line rectification can be reduced while the line is being detected.

The utility model provides a line detection circuit, referring to the structural schematic diagram of the line detection circuit of FIG1 , the line detection circuit includes a power module 10, a voltage divider circuit 20, a detection display circuit 30, a connection plug-in interface 40 and a detection switch 50;

The power module 10 is connected to the voltage divider circuit 20 and the detection and display circuit 30 respectively, the connection plug-in interface 40 is connected to the voltage divider circuit 20, the detection and display circuit 30, the first end of the detection switch 50 and the output interface 100 of the circuit to be detected respectively, and the second end of the detection switch 50 is connected to the system power ground;

The voltage divider circuit 20 is used to divide the input voltage provided by the power module 10 to obtain a divided voltage when the line detection circuit is turned on, and the detection and display circuit 30 is used to perform detection and display based on the divided voltage to achieve line detection; wherein, the line detection circuit is turned on including the first end of the detection switch 50 being connected to the second end of the detection switch 50, and the line to be detected is turned on.

In the present embodiment, the line detection circuit can be applied to the detection of various lines, such as various connection lines with resistors, so that problems can be handled in time when they occur, without the need to rectify the problems after the entire line is fully installed. Taking the existing house wiring as an example, a large amount of rectification costs are required to detect problems after the entire line is completed. Based on the above line detection circuit, the CAN communication harness can be detected after laying, without installing related parts, and problems can be found in advance, so that the entire difficulty of the line after the problem occurs can be reduced. The output interface 100 of the line to be detected is connected by connecting the plug-in interface 40, wherein the output interface 100 will be fixed for the CAN communication line, and the output end and input end of the harness can be directly connected to other lines, and then the output interface 100 of the line to be detected is detected. At this time, as long as the line to be detected is turned on, it can be determined whether the terminal resistor is installed on the CAN communication harness. The principle is that when the circuit to be detected is turned on, the first end of the detection switch 50 is connected to the second end of the detection switch 50, and then the whole circuit is in a connected state. At this time, as long as the terminal resistor is not installed (normally, two terminal resistors are connected in parallel), the total voltage of the power module 10 will be loaded on the voltage divider circuit 20. Because the voltage divider circuit 20 is connected in parallel with the detection display circuit 30, the voltage of the detection display circuit 30 is the total voltage of the power module 10 at this time. The voltage divider voltage is the voltage of the output voltage of the power module 10 divided by the detection display circuit 30 or the voltage divider circuit 20; when a terminal is installed When two terminal resistors are installed, most of the voltage of the power module 10 will be loaded on the voltage divider circuit 20. Because the voltage divider circuit 20 is connected in parallel with the detection and display circuit 30, the voltage of the detection and display circuit 30 is the minimum voltage of the power module 10, and a single terminal resistor is connected in series to divide more voltage; when two terminal resistors are installed, most of the voltage of the power module 10 will be loaded on the voltage divider circuit 20. Because the voltage divider circuit 20 is connected in parallel with the detection and display circuit 30, the voltage of the detection and display circuit 30 is the maximum voltage of the power module 10, and two terminal resistors are connected in series to divide less voltage. Then, as long as the various devices of the detection and display circuit 30 are controlled, such as the display light, to work at a high voltage, the detection of the terminal resistance and the circuit break of the CAN communication line can be completed, and then the CAN communication line does not need to be detected after all installations are completed, and the detection method is simple, which can greatly reduce the risk of comprehensive rectification of subsequent lines.

The present embodiment provides a line detection circuit, which includes a power supply module, a voltage divider circuit, a detection display circuit, a connection plug-in interface and a detection switch; the power supply module is respectively connected to the voltage divider circuit and the detection display circuit, the connection plug-in interface is respectively connected to the voltage divider circuit, the detection display circuit, the first end of the detection switch and the output interface of the line to be detected, and the second end of the detection switch is connected to the system power ground; the voltage divider circuit is used to divide the input voltage provided by the power supply module to obtain a divided voltage when the line detection circuit is turned on, and the detection display circuit is used to perform detection and display based on the divided voltage to realize line detection; wherein, the line detection circuit is turned on including the first end of the detection switch being connected to the second end of the detection switch, and the line to be detected is turned on. When the first end of the detection switch is connected to the second end of the detection switch, and the line to be detected is turned on (it is not necessary to complete the laying), the detection is carried out by directly connecting the plug-in interface with the output interface of the line to be detected, and the input voltage provided by the power module is divided by the voltage divider circuit to obtain the divided voltage, and then the detection display of the detection display circuit can be determined based on the divided voltage, thereby avoiding the phenomenon in the prior art that the detection must be carried out after the line is laid, thereby causing high difficulty in line rectification. By connecting the first end of the detection switch with the second end of the detection switch, and when the line to be detected is turned on (it is not necessary to complete the laying), the detection is carried out by directly connecting the plug-in interface with the output interface of the line to be detected, and then the entire process can be carried out after the problem is detected. Since the laying is not completed at this time, the difficulty of line rectification can be reduced while the line is being detected.

Further, referring to Figure 2, Figure 2 is a circuit connection diagram of the line detection circuit of the utility model, the voltage divider circuit 20 includes at least one voltage divider resistor R connected in sequence, the input end of the voltage divider resistor R is connected to the power module 10, and the input end of the voltage divider resistor R is connected to the connection plug-in interface 40.

Specifically, the detection display circuit 30 includes a buzzer FMQ and a detection indicator light D1, the power module 10 is respectively connected to the input end of the buzzer FMQ and the input end of the detection indicator light D1, and the connection plug-in interface 40 is respectively connected to the output end of the buzzer FMQ and the output end of the detection indicator light D1.

Specifically, the power module 10 includes a battery 11 , and an output end of the battery 11 is connected to an input end of the voltage-dividing resistor R, an input end of the buzzer FMQ, and an input end of the detection indicator light D1 .

Specifically, the power module 10 further includes a USB interface 12, and the USB interface 12 is respectively connected to an external charging device, an input end of a voltage divider resistor R, an input end of the buzzer FMQ, and an input end of the detection indicator light D1.

Specifically, the detection switch 50 includes a four-pin key switch, a first connecting pin of the four-pin key switch is connected to the connection plug-in interface, and a second connecting pin of the four-pin key switch is connected to the system power ground.

In this embodiment, the voltage-dividing resistor can be designed according to user needs, such as designing two voltage-dividing resistors in the figure, the first resistor R1 and the second resistor R2, so as to complete the voltage division. The detection display circuit 30 includes a buzzer FMQ and a detection indicator D1. Taking the above example as an example, the output voltage of the power module 10 is 3V, the voltage-dividing voltage of the voltage-dividing circuit 20 is 1V when one terminal resistor is installed, and the voltage-dividing voltage of the voltage-dividing circuit 20 is 2V when two terminal resistors are installed, and then only when the voltage-dividing voltage is 2V, the buzzer FMQ and the detection indicator D1 start to work. At this time, a display light that is only turned on at about 3V can be connected in parallel with the voltage-dividing circuit 20. When the display light shows yes, it means that the terminal resistance is not connected. It is worth noting that the buzzer FMQ and the detection indicator D1 can also be set at both ends of the connection plug-in interface 40. At this time, a low-voltage turned-on indicator light is set at both ends of the connection plug-in interface 40. When the display light shows yes, it means that the terminal resistance is not connected. Referring to Figure 3, Figure 3 is another circuit connection schematic diagram of the line detection circuit of the utility model. In order to avoid the problem of voltage reduction of the battery 11 due to use, the voltage can be directly connected through the USB interface 12, which can be the voltage of a direct power bank or a voltage generating circuit, such as a power supply circuit generated by a commonly used 3V voltage, so as to avoid the problem of voltage reduction of the battery 11. The detection switch 50 includes a four-pin key switch or other switches. Here, the four-pin key switch is used for explanation, and the two connected pins are used as output ends, and the other two connected pins are used as input ends. At the same time, a detection circuit is directly set on the input side of the power module 10, because the working principle of the whole circuit is that the voltage divider circuit 20 divides the voltage to ensure the operation of the buzzer FMQ and the detection indicator D1 in the detection display circuit 30, so the setting of the total resistance value of the voltage divider circuit 20 and the stability of the output voltage of the power module 10 are also very important. A display light that lights up about 3V (assuming that the required input voltage is 3V) can be designed, or a detection point between the input side of the power module 10 and the system power ground is set on the subsequent device, and the user can use it after the detection, so as to ensure the accuracy of the subsequent detection. The CAN communication line can then be tested through a line detection circuit, and the detection method is simple, which can greatly reduce the risk of subsequent comprehensive line rectification.

In addition, the present application also provides a line detection device, which includes a housing structure and a circuit board 630. The circuit board 630 is provided with the above-mentioned line detection circuit, and the circuit board is provided in the housing structure.

In this embodiment, the above line detection circuit is packaged as a line detection device. Please refer to Figure 4, which is a structural schematic diagram of the line detection device of the utility model. The circuit board 630 is arranged in the shell structure, which can greatly improve the convenience of use while detecting the line.

Further, referring to Figure 5, Figure 5 is another structural schematic diagram of the line detection device of the utility model, the shell structure includes an upper packaging shell 620 and a lower shell 640, the circuit board 630 is arranged on one side of the lower shell 640, and is encapsulated in a first box body composed of the upper packaging shell 620 and the lower shell 640.

Specifically, a first through hole 623, a second through hole 621 and a third through hole 622 are arranged on the upper packaging plate of the upper packaging shell 620, and a fourth through hole 624 and a fifth through hole 625 are arranged on the side packaging plate of the upper packaging shell 620, the detection switch 50 is arranged in the first through hole 623, the detection indicator light D1 in the detection display circuit 30 is arranged in the second through hole 621, the buzzer FMQ in the detection display circuit 30 is arranged in the third through hole 622, the connection plug-in interface 40 is arranged in the fourth through hole 624, and the USB interface 12 in the power module is arranged in the fifth through hole 625, wherein the line detection device also includes a connecting wire 610, one end of the connecting wire 610 is connected to the connecting plug-in interface 40, and the other end of the connecting wire 610 is connected to the line detection circuit through the fourth through hole 624.

Specifically, the shell structure also includes a battery box 650, a battery 11 and a battery cover 660. One side of the battery box 650 is arranged on the other side of the lower shell 640 away from the circuit board 630. The battery 11 is arranged in the battery box 650 and connected to the line detection circuit. The battery cover 660 is arranged on the other side of the battery box 650, and the battery box 650 and the battery 11 are encapsulated in a second box body composed of the upper encapsulation shell 620 and the battery cover 660.

In this embodiment, the entire circuit detection device simplifies the operation steps, and only needs to connect a connection plug-in interface 40 and press a detection switch 50 to complete the detection. Then, the buzzer FMQ and the detection indicator light D1 are used for sound and light indication, and the detection results are intuitively displayed. As can be seen from the figure, the button 51 is set on the upper packaging board of the upper packaging shell 620 through the first through hole 623 as the case of the detection switch 50, and there is also a second through hole 621 for displaying the detection indicator light D1 and a third through hole 622 for protruding the buzzer FMQ, so that you can press the button 51 by yourself and observe the buzzer FMQ and the detection indicator light D1. At the same time, an indicator light showing that the terminal resistance is not connected and an indicator light showing that the input voltage is normal can be set, so that observation and detection can be intuitively performed. The fourth through hole 624 and the fifth through hole 625 are respectively used to connect the connection plug-in interface 40 and the USB interface 12, so that the convenience of use can be greatly improved through the design of the connecting line 610, and the design of the USB interface 12 can improve the selectivity of the input voltage. It is worth noting that the first through hole 623, the second through hole 621, the third through hole 622, the fourth through hole 624 and the fifth through hole 625 can be arranged on the same packaging board, which is not limited here, and the internal circuit board 630, the design direction of the battery 11 can also be arranged in different ways according to actual conditions. The most direct way is to directly detect the CAN harness through the circuit board 630.

Exemplarily, the line detection device can be composed of a housing, a PCB circuit, a battery box, a battery, and a connection plug-in. The battery provides power for the detection tooling. When the connection plug-in is plugged into the CAN line, press the test button. If the indicator light is on and the buzzer beeps, it means that the CAN line is installed properly; when the test button is pressed, the indicator light is off and the buzzer is silent, it means that there is a problem with the installation of the CAN line. The CAN communication line can then be tested through the line detection circuit, and the detection method is simple, which can greatly reduce the risk of subsequent comprehensive rectification of the line.

The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the inventive concept of the present application, or direct/indirect applications in other related technical fields are included in the patent protection scope of the present application.

Claims (10)

1. A line detection circuit, characterized in that the line detection circuit comprises a power module, a voltage divider circuit, a detection display circuit, a connection plug-in interface and a detection switch; The power module is connected to the voltage divider circuit and the detection and display circuit respectively, the connection plug-in interface is connected to the voltage divider circuit, the detection and display circuit, the first end of the detection switch and the output interface of the circuit to be detected respectively, and the second end of the detection switch is connected to the system power ground; The voltage divider circuit is used to divide the input voltage provided by the power module to obtain a divided voltage when the line detection circuit is turned on, and the detection and display circuit is used to perform detection and display based on the divided voltage to achieve line detection; wherein, the line detection circuit is turned on including the first end of the detection switch being connected to the second end of the detection switch, and the line to be detected is turned on. 2. The line detection circuit as described in claim 1 is characterized in that the voltage divider circuit includes at least one voltage divider resistor connected in sequence, the input end of the voltage divider resistor is connected to the power module, and the input end of the voltage divider resistor is connected to the connection plug-in interface. 3. The line detection circuit as described in claim 2 is characterized in that the detection display circuit includes a buzzer and a detection indicator light, the power module is respectively connected to the input end of the buzzer and the input end of the detection indicator light, and the connection plug-in interface is respectively connected to the output end of the buzzer and the output end of the detection indicator light. 4. The line detection circuit as claimed in claim 3, characterized in that the power module comprises a battery, and the output end of the battery is connected to the input end of the voltage divider resistor, the input end of the buzzer and the input end of the detection indicator light. 5. The line detection circuit as described in claim 4 is characterized in that the power module also includes a USB interface, and the USB interface is respectively connected to an external charging device, an input end of a voltage divider resistor, an input end of the buzzer, and an input end of the detection indicator light. 6. The line detection circuit as described in claim 5 is characterized in that the detection switch includes a four-pin push button switch, a first connecting pin of the four-pin push button switch is connected to the connection plug-in interface, and a second connecting pin of the four-pin push button switch is connected to the system power ground. 7. A line detection device, characterized in that the line detection device comprises a housing structure and a circuit board, the circuit board is provided with the line detection circuit according to any one of claims 1 to 6, and the circuit board is provided in the housing structure. 8. The line detection device as claimed in claim 7, characterized in that the housing structure comprises an upper packaging housing and a lower housing, the circuit board is arranged on one side of the lower housing and is packaged in a first box body composed of the upper packaging housing and the lower housing. 9. The line detection device as described in claim 8 is characterized in that a first through hole, a second through hole and a third through hole are set on the upper packaging plate of the upper packaging shell, a fourth through hole and a fifth through hole are set on the side packaging plate of the upper packaging shell, the detection switch is set in the first through hole, the detection indicator light in the detection display circuit is set in the second through hole, the buzzer in the detection display circuit is set in the third through hole, the connection plug-in interface is set in the fourth through hole, and the USB interface in the power module is set in the fifth through hole, wherein the line detection device also includes a connecting wire, one end of the connecting wire is connected to the connecting plug-in interface, and the other end of the connecting wire is connected to the line detection circuit through the fourth through hole. 10. The line detection device as described in claim 9 is characterized in that the shell structure also includes a battery box, a battery and a battery cover, one side of the battery box is arranged on the other side of the lower shell, the battery is arranged in the battery box and connected to the line detection circuit, the battery cover is arranged on the other side of the battery box, and the battery box and the battery are encapsulated in a second box body composed of the upper encapsulation shell and the battery cover.