Electric leakage detection system and method
By using a parallel switch circuit and a judgment device on the circuit board, leakage phenomena can be detected quickly and accurately, and the leakage node can be located, thus solving the problem of long time consumption in the prior art.
Patent Information
- Application Number
- CN202410939818.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-15
- Publication Date
- 2026-01-16
AI Technical Summary
Existing technologies for detecting leakage between circuits on a circuit board are time-consuming and make it difficult to quickly and accurately locate the leakage point.
By employing multiple parallel switching circuits, voltage generators, controllers, and judgment devices, electrical signals are generated and it is determined whether the default threshold is exceeded by controlling whether the switching circuits are on or off, so as to quickly locate the leakage point.
It enables rapid and accurate detection of circuit board leakage and identifies leakage points, thus improving detection efficiency.
Smart Images
Figure CN121348029A_ABST
Abstract
Description
[Technical Field]
[0001] This invention relates to a leakage current detection system and method, particularly a leakage current detection system and method applied to circuit boards, which can quickly and accurately identify whether a circuit board has leakage current and find two nodes where leakage current occurs. [Background Technology]
[0002] With the development of technology, electronic products are trending towards being thinner, lighter, smaller, and more multifunctional. To achieve these goals, the circuit boards used internally often require multi-layered circuit structures with very dense wiring. However, due to this high density of wiring, such a design is prone to short circuits or leakage between lines, leading to malfunctions of the circuit board.
[0003] Please refer to Figure 1 This is a schematic circuit block diagram of a known circuit board leakage current detection device. After the circuit board is manufactured, it has many lines. To check whether these lines have been manufactured according to the design, it is necessary to check whether the impedance between these lines is abnormal (for example, checking for connections that should not be connected but are, or checking for connections that should be connected but are not). At this time, using... Figure 1 The leakage current detection device 10 calculates the electrical characteristics between any two detected nodes (e.g., nodes 101, 102, 103, 104, etc.) according to Ohm's Law to determine if there is an abnormality. For example, in Figure 1 In the process, the output terminal 11 of the leakage current detection device 10 provides a detection voltage to node 101. If there is a leakage current between node 101 and nodes 102, 103 or 104, a current signal will be measured at the input terminal 12. The voltage or resistance value between node 101 and nodes 102, 103 or 104 can be calculated according to Ohm's law, thereby determining whether the leakage current between node 101 and nodes 102, 103 or 104 has reached the standard for determining circuit board failure.
[0004] However, testing for short circuits or leakage between these lines requires testing the abnormal relationship between one line and all other lines. Therefore, when a circuit board has thousands or more lines, completing electrical tests on all of them can be time-consuming due to the large volume of tests. How to quickly and accurately identify whether a circuit board has leakage and pinpoint the point of leakage between two points has become a major challenge in the industry.
[0005] Therefore, there is an urgent need to provide a leakage current detection system and method that can quickly and accurately identify whether a circuit board has leakage current and to find two nodes where leakage current occurs. [Summary of the Invention]
[0006] One objective of this invention is to provide a leakage current detection system and method that can quickly and accurately identify whether a circuit board has leakage current and to identify two nodes where leakage current occurs.
[0007] To achieve the above objectives, in one specific embodiment, the present invention provides a leakage current detection system applied to a circuit board, the circuit board including multiple lines. The leakage current detection system includes: multiple parallel switching loops, a voltage generator, a controller, and a judgment device. In the multiple parallel switching loops, each switching loop is configured with a first switch, a second switch, and a probe connected to a node between the first switch and the second switch, the probe corresponding to one of the multiple lines on the circuit board. The voltage generator is configured to input a voltage to the first switch of each of the multiple switching loops. The controller is configured to control the conduction of the first switch and the second switch in each switching loop, so that an electrical signal is generated between any two lines on the circuit board. The judgment device is configured to be connected to the second switch to receive the electrical signal and determine whether the electrical signal is greater than a default threshold value.
[0008] In another specific embodiment, the present invention also provides a leakage current detection method applied to a circuit board, the circuit board including multiple lines, the leakage current detection method comprising the following steps: providing multiple switch loops connected in parallel, each switch loop being configured with a first switch, a second switch, and a probe connected to a node between the first switch and the second switch, the probe corresponding to one of the multiple lines of the circuit board; inputting a voltage to the first switch of the multiple switch loops; controlling whether the first switch and the second switch of each switch loop are turned on or off, so that an electrical signal is generated between any two lines on the circuit board; and receiving the electrical signal and determining whether the electrical signal is greater than a default threshold value.
[0009] In another specific embodiment, the present invention also provides a leakage current detection method applied to a circuit board, the circuit board including multiple lines, the leakage current detection method comprising the following steps: providing multiple switch circuits connected in parallel, wherein each switch circuit is configured with a first switch and a second switch; electrically connecting the multiple switch circuits to the multiple lines respectively; turning on the first switch of one of the multiple switch circuits and turning on the second switches of the remaining switch circuits; and supplying a voltage to detect whether an electrical signal exceeding a default threshold occurs between the line corresponding to the turned-on first switch and the lines corresponding to the turned-on second switches.
[0010] In summary, the leakage current detection system and method of the present invention can quickly and accurately identify whether a circuit board has leakage current and identify two nodes where leakage current occurs. [Attached Image Description]
[0011] The above-described objects and advantages of the present invention will become more immediately apparent to those skilled in the art upon reading the following detailed description and accompanying drawings. [ Figure 1 [This is a schematic circuit block diagram of a known circuit board leakage current detection device;] [ Figure 2 This is a schematic diagram of a leakage current detection system and the circuit board to be measured according to a specific embodiment of the present invention; [ Figure 3 ]for Figure 2 The leakage current detection system and its equivalent circuit diagram; [ Figure 4 ]for Figure 2 A schematic diagram of the leakage current detection system and circuit board during measurement; [ Figure 5 ]for Figure 2 Another schematic diagram of the leakage current detection system and circuit board during measurement; and [ Figure 6 [This is a flowchart of a leakage current detection method according to a specific embodiment of the present invention.]
Detailed Implementation Methods
[0012] Please refer to the accompanying drawings for the following detailed description, which illustrate various embodiments of the invention by way of example and to provide an understanding of how to implement the invention. The embodiments of the invention provide sufficient content for those skilled in the art to implement the disclosed embodiments or embodiments derived from the disclosed content. It should be noted that these embodiments are not mutually exclusive, and some embodiments can be appropriately combined with one or more other embodiments to form new embodiments; that is, the implementation of the invention is not limited to the embodiments disclosed below. Furthermore, for the sake of brevity and clarity, excessive details are not disclosed in the embodiments; even when specific details are disclosed, they are only illustrative to make the reader clear, and the relevant specific details in the embodiments are not intended to limit the disclosure of this case.
[0013] refer to Figure 2 This is a schematic diagram of a leakage current detection system and the circuit board to be measured according to a specific embodiment of the present invention. Figure 2 In this embodiment, the leakage current detection system 20 is applied to the circuit board 30. In one specific embodiment, the circuit board 30 includes multiple lines and may be a printed circuit board, an integrated circuit chip carrier board, or a display panel, but the present invention is not limited thereto.
[0014] exist Figure 2The leakage current detection system 20 of the present invention includes: a switching device 21, a voltage generator 22, a controller 23, and a judgment device 24. The switching device 21 includes multiple switching loops connected in parallel, wherein each switching loop is configured with a first switch 211, a second switch 212, and probes Pin_1, Pin_2…, Pin_n-1, Pin_n, and Pin_n+1 connected to a node 213 between the first switch 211 and the second switch 212. Probes Pin_1, Pin_2…, Pin_n-1, and Pin_n correspond to test points P_1, P_2…, P_n-1, and P_n of the multiple lines of the circuit board 30. Probe Pin_n+1 corresponds to test point 31 connected to the power / grounding area (VCC / GND) 32 of the circuit board 30. The voltage generator 22 is configured to input a voltage to the first switch 211 of the multiple switching loops of the switching device 21. The controller 23 is configured to control the conduction of the first switch 211 and the second switch 212 in each of the switching circuits, so as to generate an electrical signal, such as a voltage value or a current value, between any two lines on the circuit board 30. The judgment device 24 mainly includes a microprocessor and a detection resistor Ri (e.g., Figure 3 As shown), the purpose is to form a resistive voltage divider circuit with the insulation resistance of the circuit board and to use a microprocessor to detect the voltage division value and perform data processing. Figure 2 and Figure 3 In this system, the judgment device 24 is configured to connect to the second switch 212 to receive the electrical signal and determine whether the electrical signal is greater than a default threshold. If the electrical signal is greater than the default threshold, it can be determined that there is a leakage current on the circuit board 30. In a specific embodiment, the leakage current detection system 20 may also include a signal amplifier (not shown), electrically connected to the controller 23, to amplify the electrical signal detected by the plurality of switch circuits and then transmit it to the judgment device 24.
[0015] exist Figure 2 In circuit board 30, there is an insulation resistance Rpcb_H between any two test points P_1, P_2, ..., P_n, and an insulation resistance Rpcb_V between each test point P_1, P_2, ..., P_n and the power supply / grounding area <VCC / GND> 32. (Reference) Figure 3 , it is Figure 2 The leakage current detection system and its equivalent circuit diagram. In Figure 3In this circuit, the insulation resistance Rpcb_H and the insulation resistance Rpcb_V are connected in parallel to form the equivalent resistance Rpcb. Considering the detection resistance Ri of the judgment device 24, the voltage VRi can be obtained as VRi = 250V * [Ri / (Rpcb+Ri)]. Next, the judgment device 24 measures VRi and determines that if it is lower than the default threshold value, the circuit board passes the test; otherwise, if the measured VRi value exceeds the default threshold value, the circuit board is determined to have leakage current. In a specific embodiment, the leakage current detection system 20 may also include an analog-to-digital conversion circuit (not shown), electrically connected to the judgment device 24, to convert the voltage detected by the judgment device 24 into a digital signal and then transmit it to a display (not shown) for the user to view.
[0016] Will Figure 2 When the first switch 211 of one of the multiple switching circuits in the switching device 21 of the leakage current detection system 20 is turned on and the second switches 212 of the other switching circuits are turned on, it can detect whether there is an electrical signal exceeding the default threshold between the line corresponding to the first switch 211 and the lines corresponding to the second switches 212. For example, refer to Figure 4 , it is Figure 2 The diagram shows the leakage current detection system and circuit board during measurement. Figure 2 Of the multiple first switches 211, only the first switch 211 corresponding to probe Pin_1 is turned on, while the other first switches 211 are turned off. Figure 2 Of the multiple second switches 212, only the second switch 212 corresponding to probe Pin_1 is off, while the rest are on. At this time, test points P_2, ..., P_n in the circuit board 30 are all connected to test point 31 on the power / grounding area 32 through probes Pin_2, ..., Pin_n, Pin_n+1. There is an insulation resistance Rpcb_H between test point P_1 and test point P_2, and an insulation resistance Rpcb_V between test point P_1 and the power / grounding area <VCC / GND> 32. These can be connected in parallel to form a structure like... Figure 3The equalization resistor Rpcb is shown. If the detected VRi value exceeds the default threshold, the circuit board is determined to have leakage. Then, a portion of the second switch 212 remains on while the other portion remains off. If the detected VRi value exceeds the default threshold, the circuit board is determined to have leakage. The on portion of the second switch 212 is then divided into two parts, each set to on or off, and the detected VRi value is checked against the preset threshold until it is determined which two lines are generating the signal exceeding the default threshold. If the detected VRi value does not exceed the preset threshold, the other off portion of the second switch 212 is divided into two parts, each set to on or off, and the detected VRi value is checked against the preset threshold until it is determined which two lines are generating the signal exceeding the default threshold.
[0017] refer to Figure 5 , it is Figure 2 Another schematic diagram of the leakage current detection system and circuit board during measurement, in which, Figure 2 Among the multiple first switches 211, the first switches 211 corresponding to probes Pin_1, ..., Pin_m are turned on, while the other first switches 211 corresponding to probes Pin_m+1, ..., Pin_n are turned off. Figure 2 Of the multiple second switches 212, the second switches 212 corresponding to probes Pin_1, ..., Pin_m are off, while the remaining second switches 212 corresponding to probes Pin_m+1, ..., Pin_n are on. At this time, test points P_m+1, ..., P_n in the circuit board 30 are all connected to test point 31 on the power / grounding area 32 through probes Pin_m+1, ..., Pin_n. Only test point P_m and test point P_m+1 have an insulation resistance Rpcb_H, and test point P_1 and the power / grounding area <VCC / GND> 32 have an insulation resistance Rpcb_V. These can be connected in parallel to form a structure like... Figure 3The equivalent resistance Rpcb is shown. If the detected VRi value exceeds the default threshold, the circuit board is determined to have leakage. Then, part of the second switch 212 remains on and the other part off. If the detected VRi value exceeds the default threshold, the circuit board is determined to have leakage. The on part of the second switch 212 is then divided into two parts, each set to on or off, and the detected VRi value is checked against the preset threshold until it is determined which two lines are generating the signal exceeding the default threshold. If the detected VRi value does not exceed the preset threshold, the other part of the off second switch 212 is divided into two parts, each set to on or off, and the detected VRi value is checked against the preset threshold until it is determined which two lines are generating the signal exceeding the default threshold.
[0018] Therefore, matching Figure 2 The leakage current detection system 20 shown in the present invention provides a leakage current detection method, such as... Figure 6 As shown. The leakage current detection method is applied to circuit board 30, which contains multiple lines. Figure 6 The leakage current detection method includes the following steps. First, in step S61, multiple parallel switching circuits are provided. Each switching circuit is configured with a first switch, a second switch, and a probe connected to a node between the first switch and the second switch. The probe corresponds to one of the multiple lines on the circuit board. In step S62, a voltage is input to the first switch of each of the multiple switching circuits. In step S63, the conduction of the first switch and the second switch in each switching circuit is controlled to generate an electrical signal between any two lines on the circuit board. In step S64, the electrical signal is received and it is determined whether the electrical signal is greater than a default threshold value.
[0019] In one specific embodiment, controlling whether the first switch and the second switch of each of the multiple switch circuits are turned on or off in step S63 may include turning on the first switch of one of the multiple switch circuits and turning on the second switches of the other switch circuits, so as to detect whether there is an electrical signal exceeding the default threshold between the line corresponding to the first switch and the lines corresponding to the second switches.
[0020] In one specific embodiment, when there is an electrical signal exceeding the default threshold between the line corresponding to the first switch and the lines corresponding to the second switches, a portion of the second switches is set to conduct and the other portion of the second switches is set to cut off, in order to detect whether there is an electrical signal exceeding the default threshold between the line corresponding to the first switch and the lines corresponding to the second switches, until it is determined which two lines generate the electrical signal exceeding the default threshold.
[0021] As discussed above, the leakage current detection system and method of the present invention can quickly and accurately identify whether there is leakage current on the circuit board and identify two nodes where leakage current occurs by using multiple switching circuits.
[0022] Although the present invention has been disclosed above with reference to several embodiments or examples, it is not intended to limit the present invention. Any person skilled in the art can make some modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims. [Symbol Explanation]
[0023] 10: Leakage current detection device 101, 102, 103, 104: Nodes 11: Output terminal 12: Input terminal 20: Leakage Current Detection System 21: Switching device 211: First Switch 212: Second Switch 213: Node 22: Voltage Generator 23: Controller 24: Judgment device 30: Circuit board 31: Test point 32: Power supply / Gateway Pin_1, Pin_2, Pin_3, Pin_m, Pin_m+1, Pin_n-1, Pin_n, Pin_n+1: Probes P_1, P_2, P_3, P_m, P_m+1, P_n-1, P_n: Test points Rpcb_H, Rpcb_V, Rpcb, Ri: Insulation resistance Ri: Detection resistor S61, S62, S63, S64: Steps
Claims
1. An electric leakage detection system applied to a circuit board, the circuit board comprising a plurality of lines, the electric leakage detection system comprising: a plurality of switch loops in parallel, each switch loop being configured with a first switch, a second switch, and a probe connected to a node between the first switch and the second switch, the probe corresponding to a line of the plurality of lines of the circuit board; a voltage generator configured to input a voltage to the first switch of the plurality of switch loops; a controller configured to control the first switch and the second switch of each of the switch loops to be on or off, so that an electric signal is generated between any two lines on the circuit board; a judging device configured to be connected to the second switch to receive the electric signal and determine whether the electric signal is greater than a default threshold value.
2. The electric leakage detection system of claim 1, further comprising a signal amplifier electrically connected to the controller to amplify the electric signal detected by the plurality of switch loops.
3. The electric leakage detection system of claim 1, wherein when the first switch of one of the plurality of switch loops is on and the second switches of the other switch loops are on, the judging device detects whether the electric signal exceeding the default threshold value is between the line corresponding to the first switch and the lines corresponding to the second switches.
4. The electric leakage detection system of claim 3, wherein when the electric signal exceeding the default threshold value is between the line corresponding to the first switch and the lines corresponding to the second switches, a part of the second switches is set to be on and another part of the second switches is set to be off to detect whether the electric signal exceeding the default threshold value is between the line corresponding to the first switch and the lines corresponding to the second switches until it is determined which two lines generate the electric signal exceeding the default threshold value.
5. An electric leakage detection method applied to a circuit board, the circuit board comprising a plurality of lines, the electric leakage detection method comprising the steps of: providing a plurality of switch loops in parallel, each switch loop being configured with a first switch, a second switch, and a probe connected to a node between the first switch and the second switch, the probe corresponding to a line of the plurality of lines of the circuit board; inputting a voltage to the first switch of the plurality of switch loops; controlling the first switch and the second switch of each of the switch loops to be on or off, so that an electric signal is generated between any two lines on the circuit board; receiving the electric signal and determining whether the electric signal is greater than a default threshold value.
6. The electric leakage detection method of claim 5, further comprising the step of: amplifying the electric signal detected by the plurality of switch loops.
7. The electric leakage detection method of claim 5, further comprising the step of: making the first switch of one of the plurality of switch loops on and the second switches of the other switch loops on to detect whether the electric signal exceeding the default threshold value is between the line corresponding to the first switch and the lines corresponding to the second switches.
8. The electric leakage detection method of claim 7, further comprising the step of: when the electrical signal between the line corresponding to the first switch and the lines corresponding to the second switches exceeds the default threshold, a portion of the second switches is set to be on and another portion of the second switches is set to be off to detect whether the electrical signal between the line corresponding to the first switch and the lines corresponding to the second switches exceeds the default threshold until it is determined which two lines have the electrical signal exceeding the default threshold.
9. A leakage detection method applied to a circuit board, the circuit board comprising a plurality of lines, the leakage detection method comprising the steps of: providing a plurality of switch loops in parallel, wherein each switch loop is configured with a first switch and a second switch; electrically connecting the plurality of switch loops to the plurality of lines, respectively; turning on the first switch of the plurality of switch loops and turning on the second switches of the remaining switch loops; supplying a voltage to detect whether an electrical signal exceeding a default threshold occurs between the line corresponding to the turned-on first switch and the lines corresponding to the turned-on second switches.
10. The leakage detection method of claim 9, further comprising the steps of: when the electrical signal between the line corresponding to the first switch and the lines corresponding to the second switches exceeds the default threshold, a portion of the second switches is set to be on and another portion of the second switches is set to be off to detect whether the electrical signal between the line corresponding to the first switch and the lines corresponding to the second switches exceeds the default threshold until it is determined which two lines have the electrical signal exceeding the default threshold.