A wire harness quick detection system and method

Abstract

The application discloses a kind of wire quick detection system and method, comprising: programmable current source, for generating composite excitation signal comprising multiple continuous time periods;Double-buffered relay matrix, including first switching unit and second switching unit, first switching unit and second switching unit are alternately connected to the different pin pairs of measured wire;Weak bias network, including multiple isolation elements, each pin is connected to reference potential by isolation element;Acquisition unit is used for synchronously acquiring voltage response signal under the action of the composite excitation signal;Control unit is used for controlling the timing of the programmable current source, the double-buffered relay matrix and the weak bias network, and extracting the electrical parameter of measured wire according to the voltage response signal, the present application is combined by composite pulse excitation and double-buffered pipeline, the detection speed of millisecond level per pin pair is realized, and the detection information quantity and adaptability are improved simultaneously.

Description

Technical Field

[0001] This invention belongs to the field of ribbon cable testing technology, and relates to a rapid ribbon cable testing system and method. Background Technology

[0002] Due to its dense pins, large distributed capacitance, and easy oxidation of the contact interface, ribbon cables face three conflicting demands in production line inspection.

[0003] First, it is necessary to simultaneously test the contact resistance, the degree of oxidation at the contact interface, and the insulation leakage current.

[0004] Second, the detection speed needs to reach the millisecond level per pair of pins to match the production line cycle time.

[0005] Third, hardware costs need to be kept at a low level.

[0006] In existing technologies, both CAN bus test circuits and fuze testers use relay matrices to switch different measurement modules in a time-division manner, which cannot simultaneously meet the above three requirements. Although electrostatic discharge test systems have residual voltage discharge modules, their purpose is only to protect instruments rather than to extract leakage parameters. Although high-current breaking tests have multiple pulse sequences, they belong to the field of high-power arc extinguishing and are not technically related to the micro-current detection of ribbon cables. Therefore, a rapid ribbon cable detection system and method are needed specifically for the rapid detection of ribbon cables. Summary of the Invention

[0007] To address the above problems, this invention proposes a rapid detection system and method for ribbon cables, which effectively solves the problems in the prior art.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0009] A rapid testing system and method for ribbon cables, comprising:

[0010] A programmable current source for generating composite excitation signals that contain multiple consecutive time periods;

[0011] The double-buffered relay matrix includes a first switching unit and a second switching unit, with the first switching unit and the second switching unit alternately connected to different pin pairs of the cable under test;

[0012] The weak bias network includes multiple isolation elements, with each pin connected to a reference potential via an isolation element;

[0013] The acquisition unit is used to synchronously acquire the voltage response signal under the action of the composite excitation signal;

[0014] The control unit is used to control the timing of the programmable current source, the double-buffered relay matrix and the weak bias network, and to extract the electrical parameters of the cable under test based on the voltage response signal.

[0015] Preferably, the composite excitation signal includes a pre-bias segment, a rapid rise segment, a steady-state high current segment, a rapid fall segment, and a zero current decay segment in sequence.

[0016] The current amplitude of the pre-biased section is less than the current amplitude of the steady-state high current section.

[0017] Preferably, the zero current decay segment is divided into a leakage current extraction sub-period and a switching sub-period;

[0018] During the leakage current extraction sub-period, the weak bias network remains connected, and the acquisition unit acquires the attenuation curve; during the switching sub-period, the control unit controls the double-buffered relay matrix to perform a switching operation.

[0019] During the pre-biasing segment, the rapid rise segment, the steady-state high current segment, and the rapid fall segment, the weak bias network is disconnected.

[0020] Preferably, the weak bias network includes multiple high-resistance resistors and corresponding isolation relays, with each pin connected to a reference potential via a high-resistance resistor and an isolation relay.

[0021] Preferably, the control unit completes the zeroing operation of the preparation group in the previous measurement cycle, so that the weak bias network of the preparation group is in a stable state before the start of the current measurement cycle.

[0022] Preferably, the acquisition unit adopts a four-wire Kelvin measurement architecture, including independent Force and Sense channels.

[0023] Preferably, the electrical parameters include at least two of the following: low-current contact resistance, high-current contact resistance, nonlinear coefficient, dynamic resistance distortion, and leakage current; the nonlinear coefficient is calculated by subtracting 1 from the ratio of high-current contact resistance to low-current contact resistance; the dynamic resistance distortion is calculated by subtracting 1 from the ratio of the maximum value to the minimum value of the voltage differential curve during the rapid rise phase.

[0024] A rapid testing method for ribbon cables, applied to the aforementioned rapid testing system for ribbon cables, includes the following steps:

[0025] Step S0: In the previous measurement cycle, after completing the measurement of the current measurement group, disconnect its weak bias network to perform zeroing, and then close it again so that it reaches a stable state before the start of the next measurement cycle.

[0026] Step S1: The programmable current source and the acquisition unit are connected to the current pin pair under test through the first switching unit of the double buffer relay matrix, while the second switching unit is pre-connected to the next pin pair under test.

[0027] Step S2: Control the programmable current source to output a composite excitation signal containing multiple continuous time periods, and have the acquisition unit synchronously acquire the voltage response signal;

[0028] Step S3: Extract the electrical parameters of the tested pin pair based on the voltage response signal;

[0029] Step S4: During the zero-current attenuation segment of the composite excitation signal, switch the first switching unit to the subsequent test pin pair.

[0030] Step S5: Repeat steps S0 to S4 until all pin pairs are tested.

[0031] Preferably, in step S4, a weak bias network connection is maintained and an attenuation curve is acquired to extract the leakage current during the leakage current extraction sub-period of the zero current attenuation segment, and a switching operation is performed during the switching sub-period of the zero current attenuation segment.

[0032] Preferably, the zero-current decay period duration and the parallel capacitance value of the weak bias network are loaded according to the cable model.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] 1. This invention utilizes a programmable current source to generate a composite excitation signal comprising a pre-bias segment, a fast rise segment, a steady-state high current segment, a fast fall segment, and a zero current decay segment. This achieves the effect of simultaneously exciting three physical information parameters—contact resistance, oxidation nonlinear response, and leakage current decay—within a single pulse, avoiding the time overhead of multiple time-division measurements required by traditional methods.

[0035] 2. This invention achieves the effect of completely hiding the relay switching time within the measurement cycle by using a double-buffered relay matrix that includes a first switching unit and a second switching unit that alternately connect different pin pairs of the cable under test. This realizes the parallelization of measurement and switching and eliminates the waiting time after each switching in the traditional solution.

[0036] 3. This invention achieves the effect of separating leakage current extraction and relay switching in time and preventing them from interfering with each other by dividing the zero current attenuation segment into a leakage current extraction sub-segment and a switching sub-segment. The process of maintaining a weak bias network connection to collect the attenuation curve during the leakage current extraction sub-segment and performing the switching operation during the switching sub-segment achieves the effect of separating leakage current extraction and relay switching in time and preventing them from interfering with each other. At the same time, the switching operation is completed by utilizing the idle time of the zero current attenuation segment without adding extra test time. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the system structure of the present invention. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] The following is in conjunction with the appendix Figure 1 The specific embodiments of the present invention will be described in further detail below.

[0040] Depend on Figure 1 As shown, the fast cable detection system of the present invention includes a programmable current source, a double buffer relay matrix, a weak bias network, a data acquisition unit, and a control unit.

[0041] The programmable current source is a voltage-controlled current source built on a high-speed DA converter and operational amplifier. It has a bandwidth of no less than 1MHz and can output current signals of any waveform in the range of 1µA to 200mA, with rise and fall times not exceeding 10µs.

[0042] The dual-buffered relay matrix comprises two independent switching units, Group A and Group B. Each group contains multiple Force relays, Sense relays, and isolation relays. The two groups are independently powered and controlled by a control unit. The first and second switching units operate alternately. When one group is connected to the current pin pair under test for measurement, the other group is pre-switched to the next pin pair under test and is in standby mode.

[0043] The weak bias network consists of multiple 10-megohm high-resistance resistors and corresponding isolation relays. Each pin under test is connected to the ground reference potential through a 10-megohm resistor and an isolation relay to provide a leakage current measurement path in the zero current decay section.

[0044] The acquisition unit uses a high-speed ADC with a sampling rate of no less than 10 MSPS and a resolution of 12 bits, for synchronous acquisition of voltage response signals, such as the high-speed ADC model AD9226.

[0045] The control unit uses an FPGA, which integrates timing control logic and signal processing IP cores. It is responsible for coordinating the working timing of each component and extracting the electrical parameters of the tested cable in real time based on the collected voltage response signal.

[0046] The composite excitation signal consists of a pre-bias segment, a fast rise segment, a steady-state high current segment, a fast fall segment, and a zero current decay segment, which occur sequentially. The current amplitude in the pre-bias segment is smaller than the current amplitude in the steady-state high current segment.

[0047] The pre-bias phase lasts 100 microseconds, with the current source outputting a constant 1 mA current. This is used to measure the baseline of static contact resistance. The 1 mA current prevents oxide film breakdown and does not generate significant Joule heating. The rapid rise phase lasts 10 microseconds, with the current rising linearly from 1 mA to 100 mA. This is used to excite the nonlinear response of the contact interface. The 10 microsecond rise time corresponds to a frequency of approximately 100 kHz, which can effectively excite the semiconductor effect of the oxide film. The steady-state high-current phase lasts 50 microseconds, with the current source outputting a constant 100 mA current. This is used to measure the contact resistance under high current conditions. 100 mA simulates the upper limit of the actual operating current of the ribbon cable. The rapid fall phase lasts 5 microseconds, with the current falling linearly from 100 mA to zero. This is used to record residual inductive and thermal effects. The zero-current decay phase is preset to 3 ms, 5 ms, or 10 ms depending on the ribbon cable model. The current source output is zero, and the weak bias network is closed. This is used to measure the leakage current decay curve.

[0048] The zero-current decay segment is divided into a leakage current extraction sub-period and a switching sub-period. The leakage current extraction sub-period lasts from the start of the zero-current decay segment until 2 milliseconds before its end. During this sub-period, the weak bias network remains closed, and the ADC continuously acquires the voltage decay curve to fit the time constant and calculate the leakage current. The switching sub-period lasts for 2 milliseconds and is located at the end of the zero-current decay segment. During this sub-period, the control unit controls the double-buffered relay matrix to perform the switching operation of the current group of relays, switching the relays of the current group to the subsequent pin pair under test. Leakage current extraction and relay switching are strictly separated in time and do not interfere with each other. During the pre-bias segment, fast rise segment, steady-state high current segment, and fast fall segment, the weak bias network is in an open state to prevent high current from flowing into the weak bias network and causing interference or damage.

[0049] The specific implementation of the weak bias network is as follows: a 10-megohm high-resistance resistor is connected in series with each measured pin, and then connected to the ground reference potential through an isolation relay. The isolation relay is in the open state during the pre-bias phase, fast rise phase, steady-state high current phase, and fast fall phase, and in the closed state during the zero current decay phase. An adjustable capacitor of 100 picofarads to 1 nanofarad can be optionally connected in parallel at the weak bias node to adjust the RC time constant so that it falls within the preferred range of 1 millisecond to 5 milliseconds, ensuring that the decay curve can be fully sampled.

[0050] The specific timing sequence for the zeroing operation is as follows: In the previous measurement cycle, after a switching unit completes its measurement as part of a measurement group, the control unit immediately disconnects the corresponding weak bias isolation relay for that group, discharging the residual charge on the measured pin to ground through a 10-megohm resistor, and then re-closing the isolation relay. Afterward, the group enters the preparation group state, and its weak bias network remains closed and stable throughout the preparation period. Since the waiting time for the preparation group is typically tens to hundreds of milliseconds, far exceeding 5 times the RC time constant, the weak bias network must have already stabilized completely. Thus, in the current measurement cycle, the weak bias network of the preparation group is already in a stable state, and no zeroing operation needs to be performed during the zero current decay period.

[0051] The acquisition unit employs a four-wire Kelvin measurement architecture, with each pin pair under test using independent Force and Sense lines. The Force line applies excitation current from a programmable current source, while the Sense line acquires the voltage drop across the pin pair. The Force and Sense lines are connected to the pins under test via independent Force and Sense relays in a double-buffered relay matrix, respectively. This four-wire architecture eliminates the influence of wire resistance, relay contact resistance, and probe contact resistance on the measurement results, enabling the acquisition unit to accurately measure contact resistance changes at the milliohm level. Each double-buffered relay matrix contains 4N Force / Sense relays for N pin pairs.

[0052] The electrical parameters include five parameters: low-current contact resistance, high-current contact resistance, nonlinear coefficient, dynamic resistance distortion, and leakage current. Low-current contact resistance is calculated by dividing the average voltage of the last 50 microseconds of the pre-biasing phase by 1 mA. High-current contact resistance is calculated by dividing the average voltage of the last 30 microseconds of the steady-state high-current phase by 100 mA. The nonlinear coefficient is equal to the high-current contact resistance divided by the low-current contact resistance minus 1. A nonlinear coefficient greater than 0.1 indicates oxidation at the contact surface, and greater than 0.3 indicates severe degradation. The dynamic resistance distortion is obtained by differentiating the voltage during the rapid rise phase to obtain the dV / dI curve, which is equal to the maximum dV / dI divided by the minimum dV / dI minus 1. It characterizes the degree of nonlinearity at the contact interface and is more sensitive to the initial formation of oxide film than the nonlinear coefficient. Leakage current is calculated by fitting the natural logarithm of the voltage during the leakage current extraction sub-period of the zero-current decay phase to the time constant, combining the known weak bias resistance value and total capacitance value to calculate the insulation resistance, and then calculating based on the average voltage. A leakage current greater than 1 nanoamp indicates an insulation anomaly.

[0053] The rapid cable detection method of the present invention is applied to the above system and includes the following steps.

[0054] Step S0: In the current measurement cycle, when a switching unit completes the measurement as a measurement group, it immediately performs a zeroing operation, and then the group enters the preparation group state. Its weak bias network reaches a stable state before the start of the next measurement cycle.

[0055] In step S1, the programmable current source and the acquisition unit are connected to the current pin pair under test through the first switching unit of the double buffer relay matrix. At the same time, the second switching unit has been pre-switched and connected to the next pin pair under test, and its weak bias network is in a stable state.

[0056] Step S2: Control the programmable current source to output a composite excitation signal containing five consecutive time periods, while the acquisition unit synchronously acquires the voltage response waveform at a sampling rate of 10 MSPS.

[0057] In step S3, the signal processing unit extracts electrical parameters such as small current contact resistance, large current contact resistance, nonlinear coefficient, dynamic resistance distortion, and leakage current from the acquired voltage waveform.

[0058] Step S4: During the switching sub-period of the zero current decay segment of the composite excitation signal, the control unit switches the relay of the first switching unit to the subsequent tested pin pair.

[0059] Step S5: Repeat steps S0 to S4, with the first switching unit and the second switching unit taking turns serving as the measurement group and the preparation group until all pin pairs are tested.

[0060] The specific implementation of step S4 is as follows: During the leakage current extraction sub-period in the zero current decay segment, the weak bias network remains closed, the ADC continuously acquires the voltage decay curve, the signal processing unit takes the natural logarithm of the decay curve and fits the slope of the straight line to obtain the time constant, and then calculates the leakage current. After the leakage current extraction sub-period ends, the switching sub-period begins. The control unit controls the relay of the current switching unit to disconnect the current connection and switch to the subsequent pin pair to be tested. The switching action is completed within 2 milliseconds.

[0061] During system initialization, the operator scans the cable model using a barcode scanner. The system automatically loads the corresponding zero-current decay duration and weak bias network parallel capacitance value from a preset parameter table. The preset parameter table is obtained through offline calibration, with the distributed capacitance range pre-measured for each cable model. When the distributed capacitance is less than 100 picofarads, the zero-current decay duration is 3 milliseconds, and the parallel capacitance is 100 picofarads. When the distributed capacitance is greater than 100 picofarads but less than 1 nanofarad, the zero-current decay duration is 5 milliseconds, and the parallel capacitance is 100 picofarads. When the distributed capacitance is greater than 1 nanofarad, the zero-current decay duration is 10 milliseconds, and the parallel capacitance is 1 nanofarad. For users without offline calibration capabilities, the system provides a default set of parameters: a zero-current decay duration of 5 milliseconds and a parallel capacitance of 100 picofarads, which covers most FFC cables used in consumer electronics. Users can also manually adjust parameters through the host computer software, or use the system's built-in parameter learning function to automatically estimate the distributed capacitance and recommend the optimal parameters after performing a complete pulse measurement on a known good cable.

[0062] The following section uses a typical FFC cable as an example to fully explain the overall process.

[0063] The FFC cable is 30 cm long, with a pin pitch of 0.5 mm and 32 pins. The measured distributed capacitance is 150 picofarads. According to the preset parameter table, the zero-current decay time for this cable model is 5 milliseconds, the parallel capacitor of the weak bias network is 100 picofarads, the total capacitance is 250 picofarads, and the RC time constant is 10 megohms multiplied by 250 picofarads, equaling 2.5 milliseconds. The total duration of a single pulse is 100 microseconds + 10 microseconds + 50 microseconds + 5 microseconds + 5 milliseconds, equaling 5.165 milliseconds.

[0064] After the system is powered on and initialized, the operator scans the cable model using a barcode scanner, and the system automatically loads the corresponding parameter configuration. The control unit connects group A of the dual-buffered relay matrix to the first pair of pins, and group B is pre-connected to the second pair of pins. The weak bias network of group B has been zeroed and remains stable after completing the measurement in the previous round as the measurement group.

[0065] The test begins with the control unit directing the programmable current source to output a composite pulse to pin 1. During the pre-bias phase, the current source outputs a constant 1 mA current, the weak bias network is disconnected, and the ADC continuously samples the voltage at a sampling rate of 10 MSPS. The average voltage over the last 50 microseconds is used to calculate the small-current contact resistance. During the fast rise phase, the current linearly rises from 1 mA to 100 mA within 10 microseconds, and the ADC continuously samples the voltage to calculate the dynamic resistance distortion. During the steady-state high-current phase, the current source outputs a constant 100 mA current for 50 microseconds, and the average voltage over the last 30 microseconds is used to calculate the high-current contact resistance. During the fast fall phase, the current drops to zero within 5 microseconds, and the ADC records residual inductive and thermal effects. During the zero-current decay phase, the current source is turned off, the weak bias network is closed, and the ADC continuously samples the voltage decay curve. The first 3 milliseconds of the zero-current decay phase are the leakage current extraction sub-period, where the ADC samples the decay curve to fit the time constant and calculate the leakage current. The last 2 milliseconds of the zero-current decay phase are the switching sub-period, where the control unit switches the relays in group A to pin 3. The weak bias network of Group B remained closed and stable throughout the process, requiring no zeroing operation.

[0066] After the zero-current decay phase ends, the control unit immediately switches the measurement channel to group B and begins applying composite pulses to the second pair of pins. At the same time, group A enters the ready state, and its weak bias network remains closed. This process is repeated alternately until all 32 pairs of pins have been tested.

[0067] The signal processing unit extracts five parameters from the waveform after each measurement. Taking the first pair of pins as an example, the average voltage in the last 50 microseconds of the pre-bias phase is 1.234 mV, and the small current contact resistance is 1.234 mΩ. The average voltage in the last 30 microseconds of the steady-state high current phase is 123.8 mV, and the high current contact resistance is 1.238 mΩ. The nonlinear coefficient equals 1.238 divided by 1.234 minus 1, which equals 0.0032, less than 0.1, indicating a normal contact surface. Differentiating the voltage in the rapid rise phase yields a dynamic resistance distortion of 0.012, lower than the batch average plus three standard deviations, indicating no initial signs of oxidation. Taking the natural logarithm of the voltage in the leakage current extraction sub-period of the zero current decay phase, the fitted time constant is 2500 microseconds. The weak bias resistor is 10 megohms, and the total capacitance is 250 picofarads. 10 megohms multiplied by 250 picofarads equals 2500 microseconds. The time constant tau and the weak bias resistor R... bias Multiply by the total capacitance C total The ratio is 1.0, which is greater than 0.95, directly indicating that the insulation resistance is greater than 10 gigohms, and the insulation is good. The final comprehensive diagnosis is good, and the test passed.

[0068] For ribbon cables with contact oxidation, the nonlinear coefficient may reach 0.15, and the dynamic resistance distortion may exceed the batch average plus three standard deviations. In this case, it is considered slight contact oxidation, and cleaning and retesting are recommended. For ribbon cables with insulation abnormalities, the leakage current may reach 5 nanoamps. In this case, it is considered an insulation abnormality, and adjacent pins or substrates need to be checked. For ribbon cables with both contact degradation and insulation abnormalities, it is considered a combined fault and should be scrapped immediately.

[0069] Throughout the entire testing process, the testing time for a single pair of pins is 5.165 milliseconds, and the total testing time for 32 pairs of pins is approximately 165 milliseconds, achieving rapid detection of each pair of pins at the millisecond level.

[0070] The above values ​​are the preferred parameters for a 30 cm long, 0.5 mm pitch FFC cable. In actual applications, they can be adjusted according to the cable specifications.

[0071] This invention achieves millisecond-level detection speed per pair of pins by combining composite pulse excitation with a double-buffered pipeline, while improving the amount of detection information and adaptability.

[0072] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A rapid testing system for ribbon cables, characterized in that, include: A programmable current source for generating composite excitation signals that contain multiple consecutive time periods; The double-buffered relay matrix includes a first switching unit and a second switching unit, with the first switching unit and the second switching unit alternately connected to different pin pairs of the cable under test; The weak bias network consists of multiple isolation elements, with each pin connected to a reference potential via an isolation element. The acquisition unit is used to synchronously acquire the voltage response signal under the action of the composite excitation signal; The control unit is used to control the timing of the programmable current source, the double-buffered relay matrix and the weak bias network, and to extract the electrical parameters of the cable under test based on the voltage response signal.

2. The rapid testing system for ribbon cables according to claim 1, characterized in that: The composite excitation signal includes a pre-bias segment, a rapid rise segment, a steady-state high current segment, a rapid fall segment, and a zero current decay segment in sequence. The current amplitude of the pre-biased section is less than the current amplitude of the steady-state high current section.

3. The rapid testing system for ribbon cables according to claim 2, characterized in that: The zero current decay segment is divided into a leakage current extraction sub-period and a switching sub-period. During the leakage current extraction sub-period, the weak bias network remains connected, and the acquisition unit acquires the attenuation curve; during the switching sub-period, the control unit controls the double-buffered relay matrix to perform a switching operation. During the pre-biasing segment, the rapid rise segment, the steady-state high current segment, and the rapid fall segment, the weak bias network is disconnected.

4. The rapid testing system for ribbon cables according to claim 1, characterized in that: The weak bias network includes multiple high-resistance resistors and corresponding isolation relays, with each pin connected to a reference potential via a high-resistance resistor and an isolation relay.

5. The rapid testing system for ribbon cables according to claim 1, characterized in that: The control unit completes the zeroing operation of the preparation group in the previous measurement cycle, so that the weak bias network of the preparation group is in a stable state before the start of the current measurement cycle.

6. The ribbon cable rapid detection system according to claim 1, characterized in that: The acquisition unit adopts a four-line Kelvin measurement architecture, including independent Force and Sense channels.

7. The rapid testing system for ribbon cables according to claim 1, characterized in that: The electrical parameters include at least two of the following: low-current contact resistance, high-current contact resistance, nonlinear coefficient, dynamic resistance distortion, and leakage current; the nonlinear coefficient is calculated by subtracting 1 from the ratio of high-current contact resistance to low-current contact resistance; the dynamic resistance distortion is calculated by subtracting 1 from the ratio of the maximum to the minimum value of the voltage differential curve during the rapid rise phase.

8. A rapid testing method for ribbon cables, applied to the rapid testing system for ribbon cables according to any one of claims 1 to 7, characterized in that: Includes the following steps: Step S0: In the previous measurement cycle, after completing the measurement of the current measurement group, disconnect its weak bias network to perform zeroing, and then close it again so that it reaches a stable state before the start of the next measurement cycle. Step S1: The programmable current source and the acquisition unit are connected to the current pin pair under test through the first switching unit of the double buffer relay matrix, while the second switching unit is pre-connected to the next pin pair under test. Step S2: Control the programmable current source to output a composite excitation signal containing multiple continuous time periods, and have the acquisition unit synchronously acquire the voltage response signal; Step S3: Extract the electrical parameters of the tested pin pair based on the voltage response signal; Step S4: During the zero-current attenuation segment of the composite excitation signal, switch the first switching unit to the subsequent test pin pair. Step S5: Repeat steps S0 to S4 until all pin pairs are tested.

9. The method for rapid detection of ribbon cables according to claim 8, characterized in that: In step S4, a weak bias network connection is maintained and an attenuation curve is acquired to extract the leakage current during the leakage current extraction sub-period of the zero current attenuation segment, and a switching operation is performed during the switching sub-period of the zero current attenuation segment.

10. A rapid detection method for ribbon cables according to claim 8, characterized in that: The corresponding zero-current decay time and the parallel capacitance value of the weak bias network are loaded according to the cable type.

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