A circuit, system and PCB structure for improving the leakage performance of PCB based on FR-4 board

Abstract

The present invention discloses a circuit, a system and a PCB structure for improving the leakage performance of a PCB based on an FR‑4 plate, which are suitable for semiconductor current measurement below the picoampere level, and include: an equipotential protection layer, which is connected to a signal line and is arranged close to a signal end, and is used to ensure that the potential of the equipotential protection layer is the same as the potential of the signal end, so that there is no voltage difference between the two ends of the signal line to be protected to reduce the occurrence of a leakage state; a constant temperature protection module, which is connected to the equipotential protection layer and includes: a heating resistor, a temperature detection chip, a temperature control unit, an isolation buffer unit and an isolation power supply. Without increasing too much cost, it can be achieved by using an ordinary PCB plate FR‑4, and the picoampere level leakage test provides a dual protection effect, including equipotential protection and heating and dehumidification to increase dielectric impedance.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a circuit and a PCB structure for improving the leakage performance of a PCB based on an FR-4 board. Background Art

[0002] Printed circuit boards PCB, the most commonly used type is FR-4 epoxy board. When measuring low-value currents on the board, such as picoampere level or lower currents, there are many factors to consider. For example, the PCB itself can be a source of error, affecting the accuracy of the measurement, because current leakage and dielectric absorption current cannot be distinguished from the signal being measured. Therefore, it is desirable to minimize the impact of these error sources.

[0003] Usually, adding a protective layer technology will improve the test performance. However, Fr-4 will absorb moisture in the air when exposed to the air for a long time, causing its impedance to become lower. When the signal line carries a certain voltage, the signal will leak some current from the PCB, affecting the test performance. Summary of the invention

[0004] The purpose of the present invention is to provide a circuit, system and PCB structure for improving the leakage performance of PCB based on FR-4 board material, and picoampere level leakage test can be achieved by using ordinary PCB board FR-4 without increasing too much cost.

[0005] The present invention provides a circuit for improving the leakage performance of a PCB based on an FR-4 plate, which is suitable for measuring semiconductor currents below the picoampere level, and comprises:

[0006] An equipotential protection layer, which is connected to the signal line and is arranged close to the signal end, and is used to ensure that the potential of the equipotential protection layer is the same as the potential of the signal end, so that there is no voltage difference between the two ends of the signal line to be protected to reduce the occurrence of leakage;

[0007] The constant temperature protection module is connected to the equipotential protection layer and includes:

[0008] The heating resistor wire is used to heat the PCB board by heat conduction through the heat generated by the electric heating element itself to maintain a constant temperature environment on the PCB board;

[0009] A temperature detection chip, used to monitor the potential state of the heating resistance wire in real time and transmit the potential state to the temperature control unit;

[0010] A temperature control unit, used for sending a real-time level adjustment instruction to the heating resistance wire according to the currently monitored potential state change, so that the voltage on the equipotential protection layer is consistent with the voltage at the signal end;

[0011] An isolation buffer unit, used for acquiring the voltage of the signal end and transmitting it to the temperature control unit through an isolation power supply;

[0012] An isolated power supply, used to supply power to the constant temperature protection module and convert the input power into an isolated output power supply, the output power supply is floating and can meet any change in the level of the heating resistance wire;

[0013] In the test mode, when a PCB based on FR-4 board material is exposed to the air for a preset period of time, it absorbs moisture in the air, causing the PCB impedance to become low and the voltage carried by the signal line to leak. The constant temperature protection module provides a constant temperature environment for the signal line. While ensuring the constant temperature, the potential of the equipotential protection layer is ensured to be the same as the potential of the signal end of the signal line, thereby preventing the signal from leaking from the PCB when the signal line carries voltage.

[0014] Preferably, the signal end of the signal line serves as the output and measurement port of the entire circuit, the signal end of the signal line is connected to the external component to be measured through the center contact of the three-coaxial connector, and the signal end of the signal line is connected to one end of the equipotential protection layer through the three-coaxial connector, the other end of the equipotential protection layer is connected to one end of the heating resistor, the other end of the heating resistor is connected to the negative port of the isolation power supply, and at the same time, one end of the heating resistor is connected to the input end of the temperature control unit, the output end of the temperature control unit is connected to the positive port of the isolation power supply, the negative power port of the isolation power supply is grounded, the positive power port of the isolation power supply is externally powered, and the signal end of the signal line is connected to the positive input port of the isolation buffer unit, the negative input port of the isolation buffer unit and the output port of the isolation buffer unit are connected to the negative port of the isolation power supply.

[0015] Preferably, the input end of the temperature control unit is connected to the output end of the temperature detection chip.

[0016] Preferably, one end of the three-coaxial connector except the center contact is connected to the output high potential port set on the PCB board and the PCB main board ground, and the other end of the three-coaxial connector except the center contact is connected to the output low potential port set on the PCB board and the PCB main board ground.

[0017] Preferably, the heating resistor wire is arranged close to the signal line to be protected, so as to provide an effective heating effect to the surrounding PCB board, and at the same time perform equipotential protection on the equipotential protection layer connected to the heating resistor wire.

[0018] The present invention also provides a circuit system for improving the leakage performance of a PCB based on an FR-4 board, including the circuit for improving the leakage performance of a PCB based on an FR-4 board as described above.

[0019] The present invention also provides a PCB structure for improving the leakage performance of a PCB based on an FR-4 board material, and uses the circuit for improving the leakage performance of a PCB based on an FR-4 board material as described above. The upper surface of the PCB structure includes at least a signal line distributed in the middle, and one or more heating resistance wires are provided along the length direction of the signal line. The heating resistance wires are tightly surrounded on both sides of the signal line to form a detection area.

[0020] Preferably, a groove structure is provided around the detection area, and the groove structure isolates the detection area from the PCB area outside the detection area to form an air isolation area. The impedance of the intermediate signal is increased through the air isolation area. At the same time, the signal line and the PCB area are temperature-isolated through the air isolation area to ensure that the temperature around the signal line is constant.

[0021] Preferably, a temperature detection chip is provided in the detection area, and the temperature detection chip is arranged close to the signal end of the signal line, and the signal end of the signal line is connected to a three-coaxial connector.

[0022] Preferably, the PCB structure includes at least a signal line, a FR-4 structure layer and a PCB copper layer which are sequentially distributed from top to bottom.

[0023] With respect to the prior art, the present invention has the following beneficial effects:

[0024] 1. Circuit to improve the leakage performance of PCB based on FR-4 board: Equipotential protection layer: connected to the signal line and set close to the signal end, ensuring that the potential of the equipotential protection layer is the same as the potential of the signal end, reducing the voltage difference between the two ends of the signal line to be protected, thereby reducing the risk of leakage. Constant temperature protection module: including heating resistor wire, temperature detection chip and temperature control unit, used to maintain a constant temperature environment on the PCB board, ensure the stability of the potential state of the heating resistor wire, and then keep the voltage on the equipotential protection layer consistent with the voltage at the signal end. Isolation buffer unit: obtains the voltage at the signal end and transmits it to the temperature control unit through an isolated power supply to enhance the stability and reliability of signal transmission. Isolated power supply: supplies power to the constant temperature protection module and converts the input power into an isolated output power supply to meet any change requirements of the heating resistor wire level.

[0025] 2. Application of three-coaxial connector: The signal end of the signal line is connected to the external component to be tested through the center contact of the three-coaxial connector, and is also connected to the equipotential protection layer to ensure the stability and accuracy of signal transmission.

[0026] One end of the center contact on the triaxial connector is connected to the output high potential port on the PCB board, and the other end is connected to the output low potential port, and both are connected to the ground of the PCB motherboard to form a complete signal transmission and grounding loop, thereby improving anti-interference capability.

[0027] 3. Connection between the temperature control unit and the temperature detection chip: The input end of the temperature control unit is connected to the output end of the temperature detection chip, which monitors the potential state of the heating resistor in real time and issues adjustment instructions to ensure that the voltage on the equipotential protection layer is consistent with the voltage on the signal end. Setting of the heating resistor: Set it close to the signal line to be protected to provide effective heating effect for the surrounding PCB boards, and at the same time provide equipotential protection for the equipotential protection layer to further reduce the risk of leakage.

[0028] 4. PCB structure for improving the leakage performance of PCB based on FR-4 board: Applying the above circuit scheme, the upper surface of the PCB structure includes at least a signal line distributed in the middle and one or more heating resistors arranged along the length direction of the signal line to form a detection area. A groove structure is provided around the detection area to isolate the detection area from the external PCB area to form an air isolation area, thereby increasing the impedance of the intermediate signal and reducing the risk of leakage. A temperature detection chip is provided in the detection area, which is arranged close to the signal end of the signal line and connected to a three-coaxial connector to ensure the stability and accuracy of signal transmission. The PCB structure includes at least a signal line, a FR-4 structural layer and a PCB copper layer distributed in sequence from top to bottom to form a complete PCB structural system.

[0029] In summary, the circuit of the present invention realizes the picoampere level current test of ordinary PCB board through self-developed circuit and PCB board-level structure design, and improves the leakage performance of PCB based on FR-4 board. Through the design of equipotential protection layer, constant temperature protection module, isolation buffer unit and isolation power supply, the stability and accuracy of signal transmission are ensured, and electromagnetic interference and signal loss are reduced. The anti-interference ability and safety of the system are enhanced, and problems caused by electromagnetic interference or potential difference can be effectively prevented, ensuring the normal operation of equipment and the safety of personnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a circuit principle block diagram for improving the leakage performance of a PCB based on FR-4 board in the first embodiment of the present invention;

[0031] Figure 2 A top view of a PCB structure for improving leakage performance of a PCB based on an FR-4 board in Embodiment 1 of the present invention;

[0032] Figure 3 The figure is a side view of a signal line in a PCB structure for improving the leakage performance of a PCB based on an FR-4 board in the first embodiment of the present invention. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] like Figure 1 As shown, the present invention provides a circuit for improving the leakage performance of a PCB based on FR-4 board, which is suitable for semiconductor current measurement below the picoampere level, including:

[0035] An equipotential protection layer 2 is connected to the signal line 1 and is arranged close to the signal end, so as to ensure that the potential of the equipotential protection layer 2 is the same as the potential of the signal end, so that there is no voltage difference between the two ends of the signal line 1 to be protected to reduce the leakage state. An equipotential protection layer with the same potential as the signal end is added close to the signal port, which can reduce the leakage phenomenon because there is no voltage difference between the two sections, thereby reducing the isolation impedance requirements;

[0036] Since ordinary PCB boards have the property of hygroscopicity, a set of constant temperature protection system is added to the circuit, namely, a constant temperature protection module 3, which is connected to the equipotential protection layer 2 and includes:

[0037] The heating resistor wire is used to heat the PCB board by heat conduction through the heat generated by the electric heating element itself to maintain a constant temperature environment on the PCB board;

[0038] A temperature detection chip, used to monitor the potential state of the heating resistance wire in real time and transmit the potential state to the temperature control unit;

[0039] A temperature control unit, used for sending a real-time level adjustment instruction to the heating resistance wire according to the currently monitored potential state change, so that the voltage on the equipotential protection layer is consistent with the voltage at the signal end;

[0040] The isolation buffer unit is used to obtain the voltage of the signal end and transmit it to the temperature control unit through the isolation power supply. An isolation buffer chip is added to the circuit to obtain the voltage of the signal end. The isolation power supply ensures that the potential of the heating resistor is always consistent with the signal end, thereby achieving equipotential protection.

[0041] The isolated power supply is used to supply power to the constant temperature protection module and convert the input power into an isolated output power supply. The output power supply is floating and can meet the arbitrary change of the level of the heating resistor. The isolated power supply not only provides power for the constant temperature system, but also allows the level of the resistor to change arbitrarily because its output end is floating to meet the requirement of keeping consistent with the signal end. The above circuit ensures the stable operation of the system, reduces the impact of environmental factors (such as humidity) on circuit performance, and ensures the integrity and reliability of the signal line.

[0042] In the present embodiment, in the test mode, the PCB based on the FR-4 board material is exposed to the air for a preset time and absorbs moisture in the air, resulting in a low impedance of the PCB and leakage of the voltage carried by the signal line 1. The constant temperature protection module 3 provides a constant temperature environment for the signal line. While ensuring the constant temperature, the potential of the equipotential protection layer 2 is ensured to be the same as the potential of the signal end on the signal line 1, so as to avoid leakage of the signal from the PCB when the signal line 1 carries a voltage. The test performance can be improved by adding a protective layer technology, and the problem that the Fr-4 is exposed to the air for a long time through the above-mentioned setting will absorb moisture in the air, resulting in a low impedance. When the signal line 1 carries a certain voltage, the signal will leak some current from the PCB, affecting the test performance. The leakage can be prevented while maintaining a constant temperature, thereby improving the test performance.

[0043] Specifically, the signal end of the signal line 1 serves as the output and measurement port of the entire circuit, the signal end of the signal line is connected to the external component to be measured through the central contact of the three coaxial connector, and the signal end of the signal line is connected to one end of the equipotential protection layer through the three coaxial connector, the other end of the equipotential protection layer is connected to one end of the heating resistor, the other end of the heating resistor is connected to the negative port of the isolated power supply, and at the same time, one end of the heating resistor is connected to the input end of the temperature control unit, the output end of the temperature control unit is connected to the positive port of the isolated power supply, the negative power supply port of the isolated power supply is grounded, the positive power supply port of the isolated power supply is externally powered, and the signal end of the signal line 1 is connected to the positive input port of the isolated buffer unit, and the negative input port of the isolated buffer unit and the output port of the isolated buffer unit are connected to the negative port of the isolated power supply. It can be understood that the signal end of the signal line 1 serves as the output and measurement port of the entire circuit: this design enables the signal line 1 to directly reflect the state of the external component to be measured, provide accurate input information for subsequent signal processing, data analysis or control system, reduce intermediate links, and improve the efficiency and accuracy of signal transmission. The signal end of the signal line is connected to the external component to be tested and the equipotential protection layer through a three-coaxial connector: the use of the three-coaxial connector ensures the stability and reliability of signal transmission. At the same time, the connection with the equipotential protection layer helps to eliminate electromagnetic interference and improve signal quality. This connection method also helps to simplify the circuit layout, making the entire system more compact and easy to maintain. Introduction of equipotential protection layer: The equipotential protection layer plays a vital role in the circuit. By connecting the heating resistor wire to the negative terminal of the isolated power supply, the equipotential protection of the circuit is realized. This protection mechanism can effectively prevent arc discharge and other problems caused by potential difference, and improve the safety and stability of the circuit. Collaborative work of the heating resistor wire and the temperature control unit: As a key component of temperature control, the heating resistor wire is connected to the input terminal of the temperature control unit at one end and to the positive terminal of the isolated power supply at the other end. This connection method enables the temperature control unit to monitor the temperature change of the heating resistor wire in real time and adjust the output power as needed to achieve precise temperature control. Application of isolation buffer unit: The isolation buffer unit plays a connecting role in the entire circuit, connecting the signal end of signal line 1 to the negative port of the isolation power supply, and its negative input port and output port are also connected to the negative port of the isolation power supply, which helps to further isolate external interference and improve the stability and reliability of signal transmission. This design achieves efficient signal transmission, precise temperature control and reliable equipotential protection through reasonable circuit layout and component selection.

[0044] Specifically, the input end of the temperature control unit is connected to the output end of the temperature detection chip. This design enables the temperature control unit to directly receive the temperature signal from the temperature detection chip. The temperature detection chip is responsible for real-time monitoring of the temperature of the heating resistor or the element to be measured, and converting it into an electrical signal output. By connecting this output signal directly to the input end of the temperature control unit, it can be ensured that the temperature control unit can accurately and quickly obtain the current temperature information. At the same time, the accuracy and response speed of temperature control are improved: since the temperature detection chip can monitor temperature changes in real time and quickly transmit these changes to the temperature control unit, the temperature control accuracy of the entire system is significantly improved. Due to the reduction of delays and interference in the signal transmission process, the response speed of the system is also improved, which enables the system to more accurately control the temperature of the heating resistor to meet different application requirements.

[0045] Specifically, one end of the three coaxial connector except the center contact is connected to the output high potential port set on the PCB board and connected to the PCB main board ground, and the other end of the three coaxial connector except the center contact is connected to the output low potential port set on the PCB board and connected to the PCB main board ground. A three coaxial connector is a connector with three mutually insulated conductor layers, commonly used for high-frequency signal transmission. It consists of a center contact, an inner conductor, an insulating layer and an outer conductor. The center contact is used to transmit signals, while the inner and outer conductors are used for shielding and grounding. The two ends other than the center contact of the three coaxial connector are respectively connected to the output high potential port and the output low potential port on the PCB board, and finally connected to the PCB main board ground. This connection method forms a complete signal transmission and grounding loop. By connecting the two ends other than the center contact of the three coaxial connector to the high potential and low potential ports on the PCB board respectively, and ensuring that they are all grounded, the stability and reliability of signal transmission can be significantly improved. This design helps to reduce electromagnetic interference and signal loss, and ensure that the signal can be accurately and quickly transmitted to the destination. Since the three coaxial connector has excellent shielding performance, its application in the signal transmission system can effectively enhance the anti-interference ability of the system. By grounding the outer conductor of the connector, a Faraday cage effect can be formed to minimize the impact of external electromagnetic fields, thereby protecting internal signals from interference.

[0046] Specifically, the heating resistor wire is arranged close to the signal line to be protected, so as to provide an effective heating effect to the surrounding PCB board, and at the same time perform equipotential protection on the equipotential protection layer connected to the heating resistor wire. The design enables the resistor wire to be as close to the signal line as possible, so that the PCB area near the signal line can be heated more directly, thereby improving the heating efficiency.

[0047] The circuit principle in this embodiment is as follows: Figure 1As shown in the block diagram, the source end and the signal end are the system output and measurement ports, which need to test the picoampere-level small current, that is, the signal line that the system needs to protect. The system adds an equipotential protection layer, which has the same potential as the signal end and is adjacent to the signal port, so that there is no voltage difference between the two sections, so leakage can be reduced and the isolation impedance requirements can be reduced. Due to the hygroscopic characteristics of ordinary PCB boards, a set of constant temperature protection modules is added, including heating resistors, temperature detection chips, temperature control units, isolated power supplies and isolated buffer units. This part has a unique design. One is to add an isolated buffer chip to the circuit, take the signal end voltage, and add an isolated power supply to keep the potential of the heating resistor consistent with the signal end, which plays an equipotential protection role. Secondly, this design can make the resistor wire as close to the signal line as possible, so that it can heat the PCB near the signal line more fully and directly. The addition of the isolated power supply not only provides power for the constant temperature system, but also because it is isolated, its output end is floating, which can make the resistor wire level change arbitrarily to meet the requirement of keeping consistent with the signal end. Based on the same inventive concept, the present invention also provides a circuit system for improving the leakage performance of a PCB based on an FR-4 board, including the above-mentioned circuit for improving the leakage performance of a PCB based on an FR-4 board.

[0048] See also Figure 2 As shown, the present invention also provides a PCB structure for improving the leakage performance of a PCB based on an FR-4 board material, and the circuit for improving the leakage performance of a PCB based on an FR-4 board material as described in the above embodiment is applied. The upper surface of the PCB structure includes at least a signal line 1 distributed in the middle, and one or more heating resistors 4 are arranged along the length direction of the signal line 1. The heating resistors 4 tightly surround the detection area 5 on both sides of the signal line 1. The signal line 1 is in the middle, and the heating resistors 4 tightly surround it, which not only heats the surrounding FR-4 to dry it, but also serves as a protective layer with a unique equipotential structural design.

[0049] See also Figure 3 As shown, a groove structure 6 is provided around the detection area 5, and the groove structure 6 isolates the detection area 5 from the PCB area 7 outside the detection area to form an air isolation area. The impedance of the intermediate signal is increased by the air isolation area. At the same time, the signal line 1 and the PCB area 7 are temperature-insulated by the air isolation area to ensure that the temperature around the signal line 1 is constant. The PCB area 7 outside the heating resistor wire is completely hollowed out. This design structure can not only not affect the temperature of the surrounding circuits, but also increase the impedance of the intermediate signal layer through air isolation, thereby reducing leakage, and also improve the effect of temperature isolation, so that the temperature can be kept more on the signal line.

[0050] Specifically, a temperature detection chip 8 is provided in the detection area 5 , and the temperature detection chip 8 is arranged close to the signal end of the signal line 1 , and the signal end of the signal line 1 is connected to a triaxial connector 9 .

[0051] Specifically, the PCB structure includes at least a signal line 1, a FR-4 structure layer 10 and a PCB copper layer 11 which are sequentially distributed from top to bottom. It can be seen from the side view that a layer of PCB copper layer 11 is added under the signal line, which not only plays the role of equipotential surround signal, but also plays the role of transferring temperature, so that the temperature detection chip in the top view can fully detect the temperature condition of the entire detection area 5.

[0052] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A circuit for improving the leakage performance of a PCB based on FR-4 board, characterized in that: Suitable for sub-picoampere semiconductor current measurements, including: An equipotential protection layer, which is connected to the signal line and is arranged close to the signal end, and is used to ensure that the potential of the equipotential protection layer is the same as the potential of the signal end, so that there is no voltage difference between the two ends of the signal line to be protected to reduce the occurrence of leakage; The constant temperature protection module is connected to the equipotential protection layer and includes: The heating resistor wire is used to heat the PCB board by heat conduction through the heat generated by the electric heating element itself to maintain a constant temperature environment on the PCB board; A temperature detection chip is used to monitor the potential state of the heating resistance wire in real time and transmit it to the temperature control unit; A temperature control unit, used for sending a real-time level adjustment instruction to the heating resistance wire according to the currently monitored potential state change, so that the voltage on the equipotential protection layer is consistent with the voltage at the signal end; An isolation buffer unit, used for acquiring the voltage of the signal end and transmitting it to the temperature control unit through an isolation power supply; An isolated power supply, used to supply power to the constant temperature protection module and convert the input power into an isolated output power supply, the output power supply is floating and can meet any change in the level of the heating resistance wire; In the test mode, when a PCB based on FR-4 board material is exposed to the air for a preset period of time, it absorbs moisture in the air, causing the PCB impedance to become low and the voltage carried by the signal line to leak. The constant temperature protection module provides a constant temperature environment for the signal line. While ensuring the constant temperature, the potential of the equipotential protection layer is ensured to be the same as the potential of the signal end of the signal line, thereby preventing the signal from leaking from the PCB when the signal line carries voltage.

2. The circuit for improving the leakage performance of a PCB based on FR-4 board material as claimed in claim 1, characterized in that: The signal end of the signal line serves as the output and measurement port of the entire circuit, the signal end of the signal line is connected to the external component to be measured through the center contact of the three-coaxial connector, and the signal end of the signal line is connected to one end of the equipotential protection layer through the three-coaxial connector, the other end of the equipotential protection layer is connected to one end of the heating resistor, the other end of the heating resistor is connected to the negative port of the isolation power supply, and at the same time, one end of the heating resistor is connected to the input end of the temperature control unit, the output end of the temperature control unit is connected to the positive port of the isolation power supply, the negative power supply port of the isolation power supply is grounded, the positive power supply port of the isolation power supply is externally powered, and the signal end of the signal line is connected to the positive input port of the isolation buffer unit, the negative input port of the isolation buffer unit and the output port of the isolation buffer unit are connected to the negative port of the isolation power supply.

3. The circuit for improving the leakage performance of a PCB based on FR-4 board material as claimed in claim 1, characterized in that: The input end of the temperature control unit is connected to the output end of the temperature detection chip.

4. The circuit for improving the leakage performance of a PCB based on FR-4 board material as claimed in claim 2, characterized in that: One end of the triaxial connector except the center contact is connected to the output high potential port set on the PCB board and connected to the PCB main board ground, and the other end of the triaxial connector except the center contact is connected to the output low potential port set on the PCB board and connected to the PCB main board ground.

5. The circuit for improving the leakage performance of a PCB based on FR-4 board as claimed in claim 1, characterized in that: The heating resistor wire is arranged close to the signal line to be protected, and is used to provide an effective heating effect to the surrounding PCB board, and at the same time, to perform equipotential protection on the equipotential protection layer connected to the heating resistor wire.

6. A circuit system for improving the leakage performance of a PCB based on FR-4 board, characterized in that: The invention comprises a circuit for improving the leakage performance of a PCB based on FR-4 board material as claimed in any one of claims 1 to 5.

7. A PCB structure for improving the leakage performance of a PCB based on FR-4 board, characterized in that: A circuit for improving the leakage performance of a PCB based on an FR-4 board material as described in any one of claims 1 to 5 is applied, wherein the upper surface of the PCB structure includes at least a signal line distributed in the middle, and one or more heating resistors are provided along the length direction of the signal line, and the heating resistors are tightly surrounded on both sides of the signal line to form a detection area.

8. The PCB structure for improving the leakage performance of a PCB based on FR-4 board material as claimed in claim 7, characterized in that: A groove structure is provided around the detection area, and the groove structure isolates the detection area from the PCB area outside the detection area to form an air isolation area. The impedance of the intermediate signal is increased through the air isolation area. At the same time, the signal line and the PCB area are temperature-isolated through the air isolation area to ensure that the temperature around the signal line is constant.

9. The PCB structure for improving leakage performance of PCB based on FR-4 board material as claimed in claim 7, characterized in that: A temperature detection chip is arranged in the detection area, and the temperature detection chip is arranged close to the signal end of the signal line, and the signal end of the signal line is connected to a three-coaxial connector.

10. The PCB structure for improving leakage performance of PCB based on FR-4 board material as claimed in claim 7, characterized in that: The PCB structure at least includes a signal line, a FR-4 structure layer and a PCB copper layer which are sequentially arranged from top to bottom.

Images