Circuit sensing device

Abstract

The present invention provides a circuit sensing device. The circuit sensing device couples a first end and a second end of a circuit to be tested, and generates a voltage signal to the circuit to be tested via the first end and the second end. The circuit sensing device detects a detection voltage signal corresponding to the voltage signal via the first end and the second end to generate a detection signal, thereby obtaining a calculation result. Based on the calculation result, the device determines whether at least one voltage change of the detection voltage signal is less than a first threshold value to confirm whether the circuit to be tested is normal.

Description

Technical Field

[0001] The present invention relates to a circuit sensing device, and more particularly to a device for detecting a corresponding detection voltage signal through a first end and a second end of a circuit to be tested. Background Art

[0002] Nowadays, to determine whether two lines on a circuit substrate (e.g., a printed circuit board or wafer substrate) are insulated, an insulation inspection device must be used to determine whether the lines are insulated to ensure sufficient insulation between the lines. The insulation inspection device inspects the circuit substrate and determines whether it is a good product through insulation detection. When detecting the insulation status between lines on the circuit substrate, a detection current must be provided through a detection probe, and a feedback voltage value is obtained through an impedance element as the inspection voltage. The voltage is then compared with the current flowing through the detection probe to obtain the insulation resistance value. Based on the measured insulation resistance value, the insulation status of the circuit substrate is checked to determine whether it is good. During the detection process, there may be situations where sparks are generated between the lines due to drastic changes in the detection voltage. Therefore, when such sparks are generated, the circuit substrate is judged to be defective. Therefore, insulation detection of circuit substrates is called spark detection.

[0003] In the prior art, there is a detection device with multiple probes that contacts at least two circuits on a circuit substrate for detection. Each probe is a conductive element in the shape of a rod or even a needle, which receives a constant current provided by a constant current source to feed back a current between the two circuits, and is matched with an impedance element to obtain a detection voltage between the two circuits, that is, the detection voltage is obtained by the principle that the voltage value is the result of multiplying the current value by the impedance value. However, because the detection device of the prior art senses current, it is easy to fail to detect weak currents, or to increase the detection sensitivity of the probe, which leads to an increase in the cost of the detection device. Alternatively, it is necessary to consider the conversion of the current into a voltage signal by the impedance element and replace the impedance element matched with the detection device to obtain a better detection result.

[0004] To address the aforementioned issues, the present invention provides a circuit sensing device that utilizes a voltage power supply circuit to provide a preferred voltage signal to a circuit under test, and utilizes a voltage detection circuit to detect the detection voltage signal of the circuit under test to generate a detection signal. The device then determines whether the circuit under test is a good product based on the voltage variation of the detection signal, thereby avoiding situations where the detection current is too small and also avoiding situations where the current is converted into a voltage signal by using an impedance element. Summary of the Invention

[0005] One purpose of the present invention is to provide a circuit sensing device that utilizes a voltage signal supplied to a circuit under test and detects a corresponding detection voltage signal on the circuit under test to generate a detection signal. The device determines whether the circuit under test is good or not based on the voltage change of the detection signal, thereby avoiding the situation where the detection current is very small and avoiding the situation where the current is converted into a voltage signal by considering the combination of an impedance element.

[0006] The present invention discloses a circuit sensing device for detecting a circuit under test, wherein the circuit under test has a first terminal and a second terminal. The circuit sensing device includes a voltage supply circuit, a voltage detection circuit, and an operation control circuit. The voltage supply circuit is coupled to the first terminal and the second terminal, generates a voltage signal, and transmits it to the circuit under test through the first terminal and the second terminal. The voltage detection circuit is also coupled to the first terminal and the second terminal and is coupled in parallel with the voltage supply circuit. The voltage detection circuit detects a detection voltage signal corresponding to the voltage signal through the first terminal and the second terminal to generate a detection signal. The operation control circuit is coupled to the voltage detection circuit to receive the detection signal and perform an operation based on the detection signal to obtain an operation result corresponding to a voltage change of the detection signal. The operation control circuit determines whether the circuit under test is defective based on whether the voltage change is less than a first threshold value. Thus, the circuit sensing device of the present invention provides the voltage signal to the circuit under test. Therefore, the voltage detection circuit does not need to consider the conversion of current and impedance elements into voltage and directly receives the detection voltage signal and generates the detection signal according to the detection voltage signal, thereby avoiding the situation where the current signal is too small.

[0007] The present invention provides an embodiment, wherein the voltage power supply circuit includes a voltage generating circuit and a current limiting element, wherein the voltage generating circuit is used to generate the voltage signal, and the current limiting element is coupled between the voltage generating circuit and the circuit to be tested and limits the maximum current value corresponding to the voltage signal.

[0008] The present invention provides an embodiment, wherein the operation control circuit performs operation based on multiple voltage values ​​corresponding to the detection signal to obtain the operation result, which corresponds to the voltage change. When the voltage change is less than the first threshold value, the operation control circuit determines that the circuit under test is abnormal.

[0009] The present invention provides an embodiment, wherein when the voltage changes to a negative voltage difference, the operation control circuit obtains a maximum transition voltage based on the negative voltage difference. When the positive voltage difference after the negative voltage difference is greater than a second threshold value, the operation control circuit obtains a minimum transition voltage based on the positive voltage difference. The operation control circuit generates correction data based on the maximum transition voltage and the minimum transition voltage.

[0010] The present invention provides an embodiment, wherein the voltage detection circuit includes a voltage detection module, which is coupled to the voltage power supply circuit and the first terminal to detect the detection signal. The voltage detection module includes a first detection circuit, a second detection circuit, a differential unit, and a first analog-to-digital conversion circuit, wherein the first detection circuit is coupled to the voltage power supply circuit and the first terminal, the second detection circuit is coupled to the second terminal, and the differential unit is coupled to the first detection circuit and the second detection circuit; and the first analog-to-digital conversion circuit is coupled to the differential unit and the operation control circuit to output the detection signal to the operation control circuit.

[0011] The present invention provides an embodiment, wherein the first detection circuit includes a first gain unit, a first voltage divider circuit and a second gain unit, the first gain unit is coupled to the voltage power supply circuit and the first end point, the first voltage divider circuit is coupled to the first gain unit, has a first voltage divider unit and a second voltage divider unit, the second gain unit is coupled between the first voltage divider unit and the second voltage divider unit and coupled to the positive input end of the differential unit.

[0012] The present invention provides an embodiment, wherein the second detection circuit includes a third gain unit, a second voltage divider circuit and a fourth gain unit, the third gain unit is coupled to the second endpoint, the second voltage divider circuit is coupled to the third gain unit, has a third voltage divider unit and a fourth voltage divider unit, the fourth gain unit is coupled between the third voltage divider unit and the fourth voltage divider unit, and is coupled to the negative input terminal of the differential unit.

[0013] The present invention provides an embodiment in which the voltage detection circuit further includes a voltage-dividing detection module, which is coupled to the voltage power supply circuit and the second terminal to detect a leakage voltage signal between the first terminal and the second terminal and generate a voltage-dividing detection signal. The operation control circuit determines whether there is a leakage loop between the first terminal and the second terminal based on the leakage voltage signal.

[0014] The present invention provides an embodiment, wherein the voltage divider detection module includes a third voltage divider circuit and a second analog-to-digital conversion circuit, wherein the third voltage divider circuit has a fifth voltage divider unit and a sixth voltage divider unit, the fifth voltage divider unit is coupled to the ground end and the voltage power supply circuit, the sixth voltage divider unit is coupled to the second end point, and the second analog-to-digital conversion circuit is coupled between the fifth voltage divider unit and the sixth voltage divider unit, receives the third voltage divider signal of the third voltage divider circuit and converts it into the voltage divider detection signal for transmission to the operation control circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 : It is a block diagram of a circuit sensing device according to an embodiment of the present invention.

[0016] Figure 2: It is a block diagram of a detailed circuit of a voltage detection device according to an embodiment of the present invention.

[0017] Figure 3A : It is a waveform diagram of a detection signal abnormality according to an embodiment of the present invention.

[0018] Figure 3B : It is a schematic diagram of an abnormality of the circuit under test caused by circuit deformation according to an embodiment of the present invention.

[0019] Figure 3C : It is a schematic diagram of an embodiment of the present invention in which line debris causes abnormality in the circuit under test.

[0020] Figure 3D : It is a schematic diagram of an embodiment of the present invention showing that circuit deformation and circuit debris lead to abnormality in the circuit under test.

[0021] Figure 4 : It is a normal waveform diagram of the detection signal according to one embodiment of the present invention.

[0022] Figure 5 : It is a waveform diagram of a normal detection signal according to another embodiment of the present invention.

[0023]

Main component symbol description

[0024] 1: Circuit sensing device 10: Circuit to be tested

[0025] 20: Voltage power supply circuit 22: Voltage generation circuit

[0026] 24: Current limiting element 30: Voltage detection circuit

[0027] 32: Voltage detection module 3222: First gain unit

[0028] 3224: First voltage divider circuit 32242: First voltage divider unit

[0029] 32244: Second voltage divider unit 3226: Second gain unit

[0030] 3242: Third gain unit 3244: Second voltage divider circuit

[0031] 32442: The third voltage divider unit 32444: The fourth voltage divider unit

[0032] 3246: Fourth gain unit 34: Voltage detection module

[0033] 342: third voltage divider circuit 3422: fifth voltage divider unit

[0034] 3424: Sixth voltage divider unit 36: First analog-to-digital conversion circuit

[0035] 38: Second analog-to-digital conversion circuit 40: Operation control circuit

[0036] 42: Operation result C: capacitance

[0037] DET:Detection signal I Max : Maximum current

[0038] L: Leakage circuit R: Resistance

[0039] V1: voltage signal V2: constant voltage

[0040] V D1 : The first voltage division signal V D2 : The second voltage division signal

[0041] V D3 : The third voltage division signal V DET :Detect voltage signal

[0042] V DIFF : Differential signal V G1 : First gain signal

[0043] V G2 : Second gain signal V G3 : The third gain signal

[0044] V G4 : The fourth gain signal ΔV n : Voltage change

[0045] ΔV n+1 : Next voltage change P1: First probe

[0046] P2: Second probe T1: First endpoint

[0047] T11: Line deformation T2: Second endpoint

[0048] T22: Line debris mode 1: Mode 1

[0049] Mode 2: Mode 2 Mode 3: Mode 3 DETAILED DESCRIPTION

[0050] In order to further understand and appreciate the features and effects of the present invention, embodiments and accompanying descriptions are provided as follows:

[0051] In view of the problem that the detected current in conventional circuit sensing devices is too small to be detected, the present invention proposes a circuit sensing device to solve the problems of current detection sensitivity and the conversion of current into a voltage signal by an impedance element caused by the conventional technology.

[0052] The following further describes the characteristics and structure of a circuit sensing device disclosed in the present invention:

[0053] First, see Figure 1 , which is a block diagram of a circuit sensing device according to an embodiment of the present invention. As shown in the figure, the circuit sensing device 1 of the present invention is used to detect a circuit under test 10. The circuit under test 10 has a first terminal T1 and a second terminal T2. Therefore, the circuit sensing device 1 contacts the first terminal T1 and the second terminal T2 via a first probe P1 and a second probe P2, respectively, to form an electrical connection. The circuit sensing device 1 includes a voltage supply circuit 20, a voltage detection circuit 30, and an operation control circuit 40. The voltage supply circuit 20 is used to generate a voltage signal V1. In this embodiment, the voltage supply circuit 20 can be considered a constant voltage source, and the voltage signal V1 can be a constant voltage source signal. The voltage signal V1 is supplied to the circuit under test 10 via the first terminal T1 and the second terminal T2, thereby causing the circuit under test 10 to have a constant voltage V2 between the first terminal T1 and the second terminal T2. When the circuit is in an ideal state, the voltage signal V1 is equivalent to the constant voltage V2. The voltage detection circuit 30 is also coupled to the first terminal T1 and the second terminal T2. The voltage detection circuit 30 is connected in parallel to the circuit under test 10 and the voltage power supply circuit 20 based on the voltage detection principle, thereby detecting the detection voltage signal V corresponding to the voltage signal V1 on the circuit under test 10. DET , which is equivalent to detecting the detection voltage signal V through the first end P1 and the second end P2 of the circuit under test 10 DET , to generate a detection signal DET, and transmit it to the operation control circuit 40, so that the operation control circuit 40 performs operation according to the detection signal DET to generate an operation result 42.

[0054] Continuing from the above, since the operation result 42 corresponds to at least one voltage change ΔV of the detection signal DET n (like Figure 3A As shown), the operation control circuit 40 determines the voltage change ΔV of the detection signal DET according to the operation result 42. n Is it less than the first threshold value ΔV1 (such as Figure 3A As shown), it is determined whether the detection signal DET is abnormal. When the voltage changes ΔV nWhen the voltage difference between the first terminal P1 and the second terminal P2 of the circuit under test 10 is less than the first threshold value ΔV1, the calculation control circuit 40 determines that the detection signal DET is abnormal, and thus determines that the circuit under test is abnormal. In addition, the voltage detection circuit 30 includes a voltage detection module 32 and a voltage division detection module 34. The voltage detection module 32 detects the voltage difference between the first terminal P1 and the second terminal P2 of the circuit under test 10, while the voltage division detection module 34 detects the insulation state between the first terminal P1 and the second terminal P2.

[0055] Please also refer to Figure 2 , which is a block diagram of the detailed circuit of the circuit sensing device according to an embodiment of the present invention. As shown in the figure, the voltage power supply circuit 20 includes a voltage generating circuit 22 and a current limiting element 24, wherein the voltage generating circuit 22 generates the voltage signal V1, and the current limiting element 24 is coupled between the voltage generating circuit 22 and the circuit under test 10, and limits the maximum current value I corresponding to the voltage signal V1. Max The voltage detection circuit 30 includes a voltage detection module 32, which is coupled between the voltage power supply circuit 20 and the circuit to be tested 10 to detect the detection voltage signal V DET , in particular, coupled between the voltage power circuit 20 and the first terminal T1 to detect the detection voltage signal V DET The voltage detection module 32 includes a first detection circuit 322, a second detection circuit 324, and a differential unit 326. The first detection circuit 322 is coupled between the voltage power supply circuit 20 and the first terminal T1, the second detection circuit 324 is coupled to the second terminal T2, and the differential unit 326 is coupled to the first analog-to-digital conversion circuit 36. In other words, the voltage detection module 32 is coupled to the first analog-to-digital conversion circuit 36 ​​to output the detection signal DET to the operation control circuit.

[0056] The first detection circuit 322 includes a first gain unit 3222, a first voltage divider circuit 3224, and a second gain unit 3226. The first gain unit 3222 is coupled between the voltage power supply circuit 20 and the first terminal T1. The first voltage divider circuit 3224 is coupled to the output end of the first gain unit 3222. In particular, the first voltage divider unit 32242 of the first voltage divider circuit 3224 is coupled to the output end of the first gain unit 3222. The second voltage divider unit 32244 of the first voltage divider circuit 3224 is coupled between the first voltage divider unit 32242 and ground, thereby receiving the first gain signal V of the first gain unit 3222. G1 , and the second gain unit 3226 is coupled to the first voltage divider circuit 3224, in particular, is coupled between the first voltage divider unit 32242 and the second voltage divider unit 32244, thereby receiving the first voltage divider signal V of the first voltage divider circuit 3224. D1, to generate the second gain signal V G2 The output end of the second gain unit 3226 is coupled to the differential unit 326, and the second gain signal V G2 Output to the differential unit 326.

[0057] The second detection circuit 324 includes a third gain unit 3242, a second voltage divider circuit 3244, and a fourth gain unit 3246. The third gain unit 3242 is coupled to the second terminal T2. The second voltage divider circuit 3244 is coupled to the output end of the third gain unit 3242. In particular, the third voltage divider unit 32442 of the second voltage divider circuit 3244 is coupled to the output end of the third gain unit 3242. The fourth voltage divider unit 32444 of the second voltage divider circuit 3244 is coupled between the third voltage divider unit 32442 and ground, thereby receiving the third gain signal V of the third gain unit 3242. G3 , and the fourth gain unit 3246 is coupled to the second voltage divider circuit 3244, especially coupled between the third voltage divider unit 32442 and the fourth voltage divider unit 32444, thereby receiving the second voltage divider signal V of the second voltage divider circuit 3244. D2 , to generate a corresponding fourth gain signal V G4 The output terminal of the fourth gain unit 3246 is coupled to the differential unit 326 to generate the fourth gain signal V G4 Output to the differential unit 326.

[0058] The differential unit 326 includes a differential amplifier 3262 and a plurality of impedance units 3264 and 3266. The positive input terminal of the differential amplifier 3262 is coupled to the first impedance unit 3264 to receive the second gain signal V G2 The negative input terminal of the differential amplifier 3262 is coupled to the second impedance unit 3266 to receive the fourth gain signal V G4 The first analog-to-digital conversion circuit 36 ​​is coupled to the output terminal of the differential unit 326 and the operation control circuit 40 to receive the differential signal V generated by the differential unit 326. DIFF The detection signal DET is output to the operation control circuit 40 .

[0059] In other words, the first gain unit 3222 and the third gain unit 3242 receive the detection voltage signal V corresponding to the voltage signal V1. DET , thus correspondingly generating the first gain signal V G1 With the third gain signal V G3 , and output to the first voltage divider circuit 3224 and the second voltage divider circuit 3244. The first voltage divider circuit 3224 outputs the first gain signal V G1 Provide the first voltage divided signal VD1 To the second gain unit 3226, the second voltage divider circuit 3244 is based on the third gain signal V G3 Provide the second voltage divided signal V D2 to the fourth gain unit 3246, thereby allowing the second gain unit 3226 and the fourth gain unit 3246 to generate the second gain signal V G2 With the fourth gain signal V G4 to the differential unit 326 to output the differential signal V DIFF to the first analog-to-digital conversion circuit 36, so that the first analog-to-digital conversion circuit 36 ​​converts the differential signal V DIFF The signal is converted into the detection signal DET and output to the operation control circuit 40 .

[0060] In addition, the voltage detection circuit 30 further includes a voltage-dividing detection module 34, which includes a third voltage-dividing circuit 342 and is coupled to the second analog-to-digital conversion circuit 38, wherein the third voltage-dividing circuit 342 has a fifth voltage-dividing unit 3422 and a sixth voltage-dividing unit 3424, the fifth voltage-dividing unit 3422 is coupled to the ground terminal GND and the voltage power supply circuit 20, in particular, the ground terminal GND and the voltage generating circuit 22, the sixth voltage-dividing unit 3424 is coupled to the fifth voltage-dividing unit 3422 and the second terminal T2, and the second analog-to-digital conversion circuit 38 is coupled between the fifth voltage-dividing unit 3422 and the sixth voltage-dividing unit 3424 to receive the third voltage-dividing signal V of the third voltage-dividing circuit 342. D3 And converted into the divided voltage detection signal DIV.

[0061] That is, the voltage-dividing detection module 34 is coupled between the voltage power supply circuit 20 and the circuit under test 10 to detect a leakage voltage signal between the first terminal T1 and the second terminal T2 through the first probe P1 and the second probe P2, that is, the third voltage-dividing signal V D3 , and generates the divided voltage detection signal DIV. The operation control circuit 40 determines whether there is a leakage loop L between the first terminal T1 and the second terminal T2 according to the divided voltage detection signal DIV, that is, determines the insulation state between the first terminal T1 and the second terminal T2. Generally, the ideal state of the circuit under test 10 is that the third divided voltage signal V D3 The value of is 0, that is, the capacitance C of the leakage circuit L is 0 and the resistance R is infinite. In a non-ideal circuit state, the capacitance C is not 0 and the resistance R is not infinite, so the value of the voltage division detection signal DIV will not be 0.

[0062] Please also refer to Figure 2 and Figure 3A, which is a waveform diagram of an abnormal circuit under test according to an embodiment of the present invention. As shown in the figure, the circuit sensing device 1 of the present invention detects the detection voltage signal V in the voltage detection module 50. DET And generate the detection signal DET to allow the operation control circuit 40 to generate the operation result 42, and when the voltage changes ΔV n When the detection signal DET is less than the first threshold value ΔV1, the operation control circuit 40 determines that the detection signal DET is abnormal, and thus determines that the circuit under test is abnormal, and the operation result 42 will be as follows: Figure 3A As shown in the waveform diagram, when the voltage change ΔVn is a negative voltage difference, the operation control circuit 40 obtains the maximum transition voltage MAX according to the negative voltage difference, and enters mode 2 from mode 1. The operation control circuit 40 obtains the maximum transition voltage MAX according to the negative voltage difference (i.e., the next voltage change ΔV n+1 ) is greater than the second threshold value ΔV2, the calculation control circuit 40 obtains the minimum break voltage MIN according to the positive voltage difference and enters mode 3 from mode 2. The calculation control circuit 40 generates correction data D according to the maximum break voltage MAX and the minimum break voltage MIN. The correction data D is the correction reference data of the circuit under test 10. Figure 3B 、 Figure 3C and Figure 3D As shown, this embodiment takes the abnormality of the detection signal DET caused by the line deformation T11 as an example. The cause of the abnormality of the detection signal DET is more likely to be the presence of a line debris T22 between the lines corresponding to the first end T1 and the second end T2. Alternatively, the abnormality of the detection signal DET may be caused by both the line deformation T11 and the line debris T22. In this case, the operation control circuit 40 will determine that the circuit under test 10 is abnormal.

[0063] In addition, if Figure 4 As shown, when the circuit sensing device 1 does not detect any abnormality, it will present an inclined straight line, that is, the voltage change ΔV n is always greater than the first threshold value ΔV1. Figure 5 As shown, when the circuit sensing device 1 detects the voltage change ΔV n When the value is always greater than the first threshold value ΔV1, the curve may be a curved line in addition to being an inclined straight line.

[0064] The first voltage divider unit 32242, the second voltage divider unit 32244, the third voltage divider unit 32422, the fourth voltage divider unit 32424, the fifth voltage divider unit 3424, and the sixth voltage divider unit described above are impedance elements, which may be semiconductor elements or resistors. The first gain unit 3222, the second gain unit 3226, the third gain unit 3242, and the fourth gain unit 3246 described above are operational amplifiers. The current limiting element 24 described above is an impedance element or a transistor. The first analog-to-digital conversion circuit 36 ​​and the second analog-to-digital conversion circuit 38 described above are general analog-to-digital conversion circuits, and therefore the signal conversion process will not be further described.

[0065] As can be seen from the above description, the voltage sensing device 1 of the present invention provides the voltage signal V1 for detecting whether the circuit under test 10 is abnormal. Therefore, the voltage sensing device 1 of the present invention does not need to consider the conversion of the current signal into a voltage signal with an impedance element. Figure 3B 、 Figure 3C and Figure 3D The abnormal condition shown is only a momentary voltage change. If the current detection method is used, it is difficult to detect the current change. Therefore, the voltage sensing device 1 of the present invention has better detection sensitivity.

[0066] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the present profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A circuit sensing device for detecting a circuit to be tested, wherein the circuit to be tested has a first terminal and a second terminal, wherein: The circuit sensing device comprises: A voltage power supply circuit is coupled to the first terminal and the second terminal, and generates a voltage signal to the circuit under test; a voltage detection circuit coupled to the first terminal and the second terminal and coupled in parallel to the voltage power supply circuit, the voltage detection circuit detecting a detection voltage signal corresponding to the voltage signal at the first terminal and the second terminal to generate a detection signal; as well as an operation control circuit coupled to the voltage detection circuit, obtaining an operation result according to the detection signal, and determining whether at least one voltage change of the detection signal is less than a first threshold value according to the operation result; The operation control circuit performs an operation based on multiple voltage values ​​corresponding to the detection signal to obtain the operation result, and the operation result corresponds to the voltage change. When the voltage change is less than the first threshold value, the operation control circuit determines that the circuit under test is abnormal. When the voltage change is a negative voltage difference, the operation control circuit obtains a maximum turning voltage based on the negative voltage difference. When the positive voltage difference after the negative voltage difference is greater than a second threshold value, the operation control circuit obtains a minimum turning voltage based on the positive voltage difference. The operation control circuit generates correction data based on the maximum turning voltage and the minimum turning voltage.

2. The circuit sensing device according to claim 1, wherein: The voltage supply circuit comprises: a voltage generating circuit, generating the voltage signal; and The current limiting element is coupled between the voltage generating circuit and the circuit to be tested, and limits a maximum current value corresponding to the voltage signal.

3. The circuit sensing device according to claim 1, wherein: The voltage detection circuit includes a voltage detection module coupled between the voltage power supply circuit and the circuit to be tested and coupled to the first analog-to-digital conversion circuit to output the detection signal to the operation control circuit to detect the detection voltage signal. The voltage detection module includes: A first detection circuit is coupled to the voltage power circuit and the first terminal; A second detection circuit coupled to the second terminal; as well as The differential unit has a positive input terminal coupled to the first detection circuit and a negative input terminal coupled to the second detection circuit.

4. The circuit sensing device according to claim 3, characterized in that: The first detection circuit comprises: A first gain unit is coupled to the voltage power supply circuit and the first terminal; A first voltage divider circuit is coupled to the first gain unit and comprises a first voltage divider unit and a second voltage divider unit; as well as The second gain unit is coupled between the first voltage dividing unit and the second voltage dividing unit and is coupled to the positive input terminal of the differential unit.

5. The circuit sensing device according to claim 3, characterized in that: The second detection circuit comprises: a third gain unit coupled to the second end; A second voltage dividing circuit, coupled to the third gain unit, comprises a third voltage dividing unit and a fourth voltage dividing unit; as well as The fourth gain unit is coupled between the third voltage dividing unit and the fourth voltage dividing unit, and is coupled to the negative input terminal of the differential unit.

6. The circuit sensing device according to claim 1, wherein: The voltage detection circuit further includes a voltage-dividing detection module, which is coupled between the voltage power supply circuit and the circuit to be tested and coupled to a second analog-to-digital conversion circuit to detect a leakage voltage signal between the first terminal and the second terminal and generate a voltage-dividing detection signal. The operation control circuit determines whether there is a leakage circuit between the first terminal and the second terminal based on the leakage voltage.

7. The circuit sensing device according to claim 6, characterized in that: The voltage detection module includes: The third voltage divider circuit has a fifth voltage divider unit and a sixth voltage divider unit. The fifth voltage divider unit is coupled to the ground end and the voltage power supply circuit, and the sixth voltage divider unit is coupled to the second end point. The second analog-to-digital conversion circuit is coupled between the fifth voltage divider unit and the sixth voltage divider unit, and receives the third voltage divider signal of the third voltage divider circuit and converts it into the voltage divider detection signal.

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