Method and device for testing SMD (Surface Mount Device) aluminum electrolytic capacitor

Abstract

The invention discloses a chip aluminum electrolytic capacitor testing method and device, and relates to the technical field of capacitor testing, and the method comprises the steps: cleaning a bonding pad to remove an oxide layer and residual soldering paste, and obtaining the cleanliness of the bonding pad; determining a contact resistance threshold based on the rated equivalent series resistance, and constructing an Rc-pressure corresponding model to match the optimal contact pressure; clamping the sample and verifying that the contact resistance is less than or equal to a threshold; initial capacitance, loss and equivalent series resistance are collected, and leakage current is collected after discharging; dynamic correction parameters of a correction coefficient library are called in combination with temperature and humidity; single parameter judgment and correlation verification are carried out on the standard parameters, and qualified / potential failure / unqualified results are output. The device comprises a bonding pad cleaning pretreatment module, a contact resistance calibration module, a sample clamping and fixing module, an initial parameter acquisition and discharge module, an environment self-adaptive correction module and a qualification judgment module. According to the invention, the test precision and efficiency are improved, the missed judgment rate is reduced, and the method is suitable for chip capacitor delivery and feeding inspection.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of capacitor testing, in particular to a patch aluminum electrolytic capacitor testing method and device. BACKGROUND

[0002] As the core energy storage and filtering element of electronic devices, patch aluminum electrolytic capacitors are widely used in consumer electronics, automotive electronics, industrial control and other fields, and their performance directly determines the stability and service life of downstream circuits. This type of capacitor relies on SMT patch packaging technology, and the "terminal plate" assembled at the bottom needs to meet strict size accuracy and sealing requirements. The testing process after packaging is the key to intercepting unqualified products and avoiding circuit failures - core parameters such as capacitance, loss, and leakage current need to be tested and verified to ensure that the capacitor meets the functional requirements of different scenarios, so establishing an efficient and accurate testing method is of great significance to industry production and quality control.

[0003] The existing patch aluminum electrolytic capacitor testing method and device, due to the lack of external terminal pins in patch capacitors, can easily cause poor contact due to oxidation or residual solder paste, which can introduce parasitic resistance interference, equivalent series resistance, leakage current, and other parameters affecting the testing accuracy. At the same time, the influence of environmental temperature and humidity on the parameters is not considered, and there is a lack of dynamic correction mechanism, leading to data drift in non-standard environments. In addition, there is no standardized process during clamping, and improper adjustment of vacuum suction pressure and contact pressure can easily cause sample displacement, further reducing the repeatability of the test, making it difficult to meet the testing needs of high-precision application scenarios. Therefore, a patch aluminum electrolytic capacitor testing method and device are needed to solve the above problems. SUMMARY

[0004] To solve the above technical problems, a patch aluminum electrolytic capacitor testing method and device are provided, which solve the problem of the existing patch aluminum electrolytic capacitor testing method and device in the background art, which can easily cause poor contact due to the lack of external terminal pins in patch capacitors, oxidation or residual solder paste, which can introduce parasitic resistance interference, equivalent series resistance, leakage current, and other parameters affecting the testing accuracy. At the same time, the influence of environmental temperature and humidity on the parameters is not considered, and there is a lack of dynamic correction mechanism, leading to data drift in non-standard environments. In addition, there is no standardized process during clamping, and improper adjustment of vacuum suction pressure and contact pressure can easily cause sample displacement, further reducing the repeatability of the test, making it difficult to meet the testing needs of high-precision application scenarios.

[0005] To achieve the above purposes, the technical scheme adopted by the present application is as follows: A patch aluminum electrolytic capacitor testing method, comprising: cleaning the pads of the patch aluminum electrolytic capacitor to remove the oxidation layer and residual solder paste and obtain the cleanliness of the pads; Obtain the rated equivalent series resistance of the sample, determine the contact resistance threshold, collect the contact resistance data under different contact pressures, establish the Rc-pressure corresponding model, and match the optimal contact pressure; Put the pretreated sample into the patch test fixture, fix it by vacuum adsorption, adjust the contact pressure to the optimal value, and verify that the contact resistance is less than or equal to the preset threshold; First, obtain the initial capacitance, initial loss, and initial equivalent series resistance of the sample, further complete sample discharge, and collect the initial stable leakage current; Real-time collection of environmental temperature and humidity, dynamic correction of the initial capacitance, initial loss, initial equivalent series resistance, and initial stable leakage current of the sample by calling the correction coefficient library, to obtain the standard capacitance, standard loss, standard equivalent series resistance, and standard stable leakage current of the sample; Perform single-parameter eligibility determination on the standard capacitance, standard loss, standard equivalent series resistance, and standard stable leakage current of the sample, and then start associated verification on the parameters that meet the preset parameter threshold, and output the determination results of sample eligibility, potential failure, or unqualified.

[0006] In an optional embodiment, the pads of the patch aluminum electrolytic capacitor are cleaned to remove the oxide layer and residual solder paste, and the pad cleanliness is obtained, specifically including: Obtain the model specification of the patch aluminum electrolytic capacitor, determine the length and width of the pad, and further determine the pad area; Based on the pad area, determine the power and cleaning time of the ultrasonic cleaning tool; Start the ultrasonic cleaning tool to clean the pad for the first time; Obtain the pad image after the first cleaning, and further determine the residual area of the pad oxide layer; According to the ratio of the residual area to the pad area, obtain the secondary cleaning evaluation value; Set a secondary cleaning evaluation threshold and determine whether secondary cleaning is needed. If the secondary cleaning evaluation value is greater than the secondary cleaning evaluation threshold, perform secondary cleaning. If the secondary cleaning evaluation value is less than or equal to the secondary cleaning evaluation threshold, stop cleaning; Determine the pad image after final cleaning, again obtain the residual area ratio, and obtain the pad cleanliness; If the pad cleanliness is greater than or equal to the pad cleanliness threshold, the sample pretreatment is confirmed to be completed; The calculation formula of the power and cleaning time of the ultrasonic cleaning tool is: In the formula, P is the power of the ultrasonic cleaning tool, A is the pad area, T is the cleaning time of the ultrasonic cleaning tool, For cleaning power coefficient, This is the cleaning time coefficient; The formula for calculating the cleanliness of the solder pads is: In the formula, For pad cleanliness, This represents the ratio of the residual area in the final cleaned pad image.

[0007] In an optional embodiment, the steps of obtaining the sample's rated equivalent series resistance, determining the contact resistance threshold, collecting contact resistance data under different contact pressures, establishing an Rc-pressure correspondence model, and matching the optimal contact pressure specifically include: The contact resistance threshold is obtained based on the rated equivalent series resistance of the chip aluminum electrolytic capacitor. The test range of contact pressure is determined by the contact resistance threshold. Based on the test range of contact pressure, pressure points are selected according to a preset step interval, and the contact resistance corresponding to each pressure point is collected by a micro-ohmmeter to obtain pressure-contact resistance data. Based on the pressure-contact resistance data, an Rc-pressure correspondence model is established; The minimum pressure value that satisfies the contact pressure being less than or equal to the contact resistance threshold is determined using the Rc-pressure correspondence model, and is taken as the optimal contact pressure. Based on the optimal contact pressure, adjust the pressure adjustment component of the patch test fixture, collect the real-time contact resistance again, obtain the first contact resistance, verify that the first contact resistance is less than or equal to the contact resistance threshold, and complete the contact resistance collaborative calibration. The formula for the Rc-pressure correspondence model is as follows: In the formula, For contact resistance, To contact pressure, The slope is the fitted slope. The intercept is the fitting angle.

[0008] In an optional embodiment, the step of placing the pretreated sample into a patch test fixture, fixing it by vacuum adsorption, adjusting the contact pressure to an optimal value, and verifying that the contact resistance is less than or equal to a preset threshold specifically includes: Based on the optimal contact pressure, obtain the drive current of the clamp pressure regulating component; Based on the driving current, a control signal is output to the clamp pressure regulating component to adjust the initial contact pressure to the optimal contact pressure. Obtain the vacuum adsorption system parameters of the fixture, preset the adsorption negative pressure threshold, start the vacuum adsorption device, and collect the real-time adsorption pressure; Confirming the sample preliminary fixation based on a determination result that the real-time adsorption pressure is less than or equal to the adsorption negative pressure threshold value; Obtaining a sample position image after preliminary fixation, determining an offset amount Δx, Δy of a sample center and a fixture test site center, and determining that the position is qualified if Δx≤0.1 mm and Δy≤0.1 mm, otherwise, fine-tuning the adsorption platform position; Obtaining a determination result of the position being qualified, and collecting a real-time contact resistance again to obtain a second contact resistance; Confirming the sample one-time clamping fixation based on a verification result that the second contact resistance is less than or equal to the contact resistance threshold value; The calculation formula of the driving current of the fixture pressure adjusting assembly is: In the formula, is a pressure-current conversion coefficient, is a driving current, is an optimal contact pressure.

[0009] In an optional embodiment, the obtaining of the initial capacitance, the initial loss, and the initial equivalent series resistance of the sample specifically includes: Determining an LCR test frequency based on the rated capacitance of the aluminum electrolytic capacitor patch; Setting a test voltage according to the LCR test frequency; Collecting an initial impedance signal of the sample based on the LCR test frequency and the test voltage, and decomposing to obtain a resistance component and a reactance component; Determining the initial capacitance through the reactance component; Determining the initial loss tanδ=R×2πfC based on the resistance component and the initial capacitance, and in combination with the test frequency LCR test frequency; Switching to an ESR test mode based on the LCR test frequency, and collecting a real-time equivalent series resistance of the sample; Taking the difference between the real-time equivalent series resistance and the first contact resistance as the initial equivalent series resistance; The calculation formula of the initial capacitance is: In the formula, is the initial capacitance, is the reactance component; The calculation formula of the initial loss is: In the formula, is the initial loss, is the resistance component, is the initial capacitance.

[0010] In an optional embodiment, the further completing the sample discharge and collecting the initial stable leakage current specifically comprises: After the high-frequency LCR module test is completed, the discharge module is started, and the discharge resistance is set; The rated voltage of the sample is obtained, and a discharge time threshold is determined; The working time of the discharge module is controlled to be greater than or equal to the discharge time threshold, and the residual voltage of the sample after discharge is collected; When the residual voltage is less than or equal to 0.05 times the rated voltage, it is confirmed that the discharge is completed; The leakage current test voltage is set based on the rated voltage of the sample; Based on the leakage current test voltage, the voltage is slowly applied by the leakage current module, and the stable leakage current is collected after the voltage is maintained for a preset duration; The value of the stable leakage current is verified to be within the range of 0 to the rated value of the stable leakage current, thereby determining the initial stable leakage current.

[0011] In an optional embodiment, the real-time environment temperature and humidity are collected, and the initial capacitance, initial loss, initial equivalent series resistance, and initial stable leakage current of the sample are dynamically corrected by calling a correction coefficient library to obtain the standard capacitance, standard loss, standard equivalent series resistance, and standard stable leakage current of the sample. Specifically, it comprises: The real-time environment temperature and real-time relative humidity are collected by using the temperature and humidity sensor integrated in the test platform; The temperature correction coefficient and humidity correction coefficient corresponding to the initial capacitance, initial loss, initial equivalent series resistance, and initial stable leakage current are obtained by using the pre-constructed correction coefficient library; Based on the real-time environment temperature, the initial capacitance, and the temperature correction coefficient corresponding thereto, the initial capacitance is calibrated to obtain the standard capacitance; Based on the real-time environment temperature, the initial loss, and the temperature correction coefficient corresponding thereto, the corrected loss is obtained as the standard loss; Based on the real-time environment temperature, the initial equivalent series resistance, and the temperature correction coefficient corresponding thereto, the corrected standard equivalent series resistance is obtained; Based on the real-time relative humidity, the initial stable leakage current, and the humidity correction coefficient corresponding thereto, the corrected standard stable leakage current is obtained.

[0012] In an optional embodiment, the standard capacitance, standard loss, standard equivalent series resistance, and standard stable leakage current of the sample are subjected to single-parameter qualification determination, specifically comprising: The single-parameter qualification thresholds of capacitance, loss, equivalent series resistance, and stable leakage current are obtained in sequence from the specification book of the patch aluminum electrolytic capacitor; further determine the capacitance deviation threshold, the loss threshold, the equivalent series resistance threshold, and the leakage current threshold; based on the corrected standard capacitance, standard loss, standard equivalent series resistance, and standard stable leakage current, respectively determine a capacitance deviation rate, an equivalent series resistance deviation rate; further determine whether the capacitance deviation rate is within the capacitance deviation threshold, whether the standard loss is less than or equal to the loss threshold, whether the standard equivalent series resistance is within the equivalent series resistance threshold, and whether the standard stable leakage current is less than or equal to the leakage current threshold, and synchronously obtain a single-parameter first determination result; based on the single-parameter first determination result, filter out the standard capacitance, standard loss, standard equivalent series resistance, or standard stable leakage current whose value is within a first single-parameter threshold to a second single-parameter threshold, and record the parameter type close to the threshold; based on the parameter type close to the threshold, call a preset associated threshold rule; based on the associated threshold rule, check whether the other three parameters meet the requirements; if all single parameters are qualified and the associated check passes, determine that the sample is qualified; if all single parameters are qualified but the associated check does not pass, determine that the sample is potentially failed; if any single parameter exceeds the threshold, determine that the sample is unqualified; further record a single-parameter second determination result, and based on the single-parameter second determination result, mark the sample state.

[0013] In an optional embodiment, the associated check is started on the parameters meeting the preset parameter threshold, and a determination result of sample qualification, potential failure, or unqualification is output, specifically including: based on the single-parameter second determination result, divide the samples into three categories of qualified, potentially failed, and unqualified; obtain the standard capacitance, standard loss, standard equivalent series resistance, and standard stable leakage current of the qualified samples, record the sample model, test time, environmental parameters, and contact resistance, and generate a single-sample test report in a tabular format; obtain the label of the potentially failed samples, output a retest prompt signal, and clearly indicate the parameters that need to be retested and the reason why the associated check does not pass; obtain the parameter values of the potentially failed samples after retesting, repeat the dynamic correction and qualification determination process, and update the sample state; record the test reports and states of all samples, generate a batch test summary report, and include the qualified quantity, unqualified quantity, potentially failed quantity, and key parameter statistical distribution.

[0014] Further, a patch aluminum electrolytic capacitor testing device is provided for implementing any of the above testing methods, including: A pad cleaning pretreatment module is used for cleaning the pads of the patch aluminum electrolytic capacitor, removing the oxide layer and residual solder paste, and obtaining pad cleanliness; A contact resistance calibration module is used for obtaining the sample rated equivalent series resistance, determining the contact resistance threshold, collecting the contact resistance data under different contact pressures, establishing the Rc-pressure corresponding model, and matching the optimal contact pressure. A sample clamping and fixing module is used for placing the pretreated sample into the patch test fixture, fixing it by vacuum adsorption, adjusting the contact pressure to the optimal value, and verifying that the contact resistance is less than or equal to the preset threshold. An initial parameter collection and discharge module is used for first obtaining the initial capacitance, initial loss and initial equivalent series resistance of the sample, further completing sample discharge, and collecting the initial stable leakage current. An environment adaptive correction module is used for collecting the environmental temperature and humidity in real time, calling the correction coefficient library to dynamically correct the initial capacitance, initial loss, initial equivalent series resistance and initial stable leakage current of the sample, and obtaining the standard capacitance, standard loss, standard equivalent series resistance and standard stable leakage current of the sample. A qualification determination module is used for performing single-parameter qualification determination on the standard capacitance, standard loss, standard equivalent series resistance and standard stable leakage current of the sample, and starting associated verification on the parameters meeting the preset parameter threshold, and outputting the determination result of sample qualification, potential failure or unqualification.

[0015] Compared with the prior art, the beneficial effects of the present application are: The patch aluminum electrolytic capacitor test method provided by the present application removes the oxide layer and residual solder paste by cleaning the pads of the patch aluminum electrolytic capacitor, and cleans twice, evaluates whether to clean again after the first cleaning based on the residual area ratio, realizes the surface of the pad without interfering impurities, provides a basis for subsequent contact resistance stability, avoids parameter test deviation caused by pad pollution, determines the contact resistance threshold by obtaining the sample rated equivalent series resistance, collects the contact resistance data under different contact pressures to establish the Rc-pressure corresponding model, matches and verifies the optimal contact pressure, realizes precise control of the contact resistance within the threshold, reduces the interference of parasitic contact resistance on ESR, loss and other low resistance / high frequency parameters, and improves the core parameter test precision. The patch aluminum electrolytic capacitor test method provided by the scheme realizes stable clamping of the sample without displacement, avoids test data drift caused by loose clamping, guarantees test repeatability, collects the initial capacitance, initial loss and initial equivalent series resistance of the sample first, determines the LCR test frequency based on the rated capacity and decomposes the impedance signal, then starts the discharge module, controls the discharge time to be greater than or equal to a threshold value, verifies that the residual voltage is less than or equal to 0.05 times the rated voltage, and collects the initial stable leakage current, which realizes elimination of the interference of the residual voltage of the sample on the leakage current test and ensures that the initial four-parameter collected data is accurate and reliable. The patch aluminum electrolytic capacitor test method provided by the scheme realizes stable clamping of the sample without displacement, avoids test data drift caused by loose clamping, guarantees test repeatability, collects the initial capacitance, initial loss and initial equivalent series resistance of the sample first, determines the LCR test frequency based on the rated capacity and decomposes the impedance signal, then starts the discharge module, controls the discharge time to be greater than or equal to a threshold value, verifies that the residual voltage is less than or equal to 0.05 times the rated voltage, and collects the initial stable leakage current, which realizes elimination of the interference of the residual voltage of the sample on the leakage current test and ensures that the initial four-parameter collected data is accurate and reliable. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 The flowchart of the patch aluminum electrolytic capacitor test method provided by the present application is shown in the figure. Figure 2 The flowchart of the pad cleanliness acquisition in the present application is shown in the figure. Figure 3 The flowchart of the optimal contact pressure acquisition in the present application is shown in the figure. Figure 4 The framework diagram of the patch aluminum electrolytic capacitor test device provided by the present application is shown in the figure. DETAILED DESCRIPTION

[0017] The following description is used to disclose the present application so that those skilled in the art can implement the present application. The preferred embodiments in the following description are only as examples, and other obvious modifications can be thought of by those skilled in the art.

[0018] REFERENCE Figure 1 - Figure 4 As shown in the figure, a patch aluminum electrolytic capacitor test method comprises: Cleaning the pads of the patch aluminum electrolytic capacitor, removing the oxide layer and residual solder paste, and obtaining the pad cleanliness; Obtaining the rated equivalent series resistance of the sample, determining the contact resistance threshold, collecting the contact resistance data under different contact pressures, establishing the Rc-pressure corresponding model, and matching the optimal contact pressure; Put the pretreated sample into the patch test fixture, fix it by vacuum suction, adjust the contact pressure to the optimal value, and verify that the contact resistance is less than or equal to the preset threshold; First, obtain the initial capacitance, initial loss, and initial equivalent series resistance of the sample, further complete the sample discharge, and collect the initial stable leakage current; Real-time collection of environmental temperature and humidity, dynamic correction of the initial capacitance, initial loss, initial equivalent series resistance, and initial stable leakage current of the sample by calling the correction coefficient library, to obtain the standard capacitance, standard loss, standard equivalent series resistance, and standard stable leakage current of the sample; Perform single-parameter qualification on the standard capacitance, standard loss, standard equivalent series resistance, and standard stable leakage current of the sample, and then start associated verification on the parameters that meet the preset parameter threshold, and output the qualification, potential failure, or unqualified judgment result of the sample.

[0019] Further, cleaning the pads of the patch aluminum electrolytic capacitor, removing the oxide layer and residual solder paste, and obtaining the pad cleanliness, specifically including: Obtaining the model specification of the patch aluminum electrolytic capacitor, determining the length and width of the pad, and further determining the pad area; Based on the pad area, determine the power and cleaning time of the ultrasonic cleaning tool; Start the ultrasonic cleaning tool to clean the pad for the first time; Obtain the pad image after the first cleaning, and further determine the residual area of the pad oxide layer; According to the ratio of the residual area to the pad area, obtain the secondary cleaning evaluation value; Set the secondary cleaning evaluation threshold, and determine whether secondary cleaning is needed. If the secondary cleaning evaluation value is greater than the secondary cleaning evaluation threshold, perform secondary cleaning. If the secondary cleaning evaluation value is less than or equal to the secondary cleaning evaluation threshold, stop cleaning; Determine the pad image after final cleaning, again obtain the residual area ratio, and obtain the pad cleanliness; Based on the judgment standard of pad cleanliness K≥95%, confirm that the sample pretreatment is completed; The calculation formula of the power and cleaning time of the ultrasonic cleaning tool is: In the formula, is the power of the ultrasonic cleaning tool, the pad area, a cleaning time of the ultrasonic cleaning tool, a cleaning power coefficient, a cleaning time coefficient; a calculation formula of the pad cleanliness is: in the formula, the pad cleanliness, a residual area ratio of the pad image after final cleaning.

[0020] Specifically, the secondary cleaning power P' = 1.1 x P, and the time t' = 1.2 x t. If the length L and the width W of the pad, then the pad area S = L x W. The value range of the cleaning power coefficient is 0.8-1.2 W / mm². The value range of the cleaning time coefficient is 0.5-0.8 s / mm². The secondary cleaning evaluation threshold is 5%.

[0021] Further, the rated equivalent series resistance of the sample is obtained, the contact resistance threshold is determined, the contact resistance data under different contact pressures is collected, the Rc-pressure corresponding model is established, and the optimal contact pressure is matched, specifically including: based on the rated equivalent series resistance of the patch aluminum electrolytic capacitor, the contact resistance threshold is obtained; determine the test range of the contact pressure through the contact resistance threshold; based on the test range of the contact pressure, select the pressure points according to the preset step interval, collect the contact resistance corresponding to each pressure point through the micro-ohm meter, and obtain the pressure-contact resistance data; according to the pressure-contact resistance data, the Rc-pressure corresponding model is established; through the Rc-pressure corresponding model, the minimum pressure value satisfying the contact pressure less than or equal to the contact resistance threshold is solved as the optimal contact pressure; according to the optimal contact pressure, adjust the pressure adjusting assembly of the patch test fixture, collect the real-time contact resistance again to obtain the first contact resistance, verify that the first contact resistance is less than or equal to the contact resistance threshold, and complete the contact resistance cooperative calibration; wherein, the expression formula of the Rc-pressure corresponding model is: in the formula, the contact resistance, the contact pressure, the fitting slope, the fitting intercept.

[0022] wherein the contact resistance threshold R c0 = 0.06 × rated equivalent series resistance, ensuring that the contribution of contact resistance to the ESR test error is ≤3%. Based on the contact resistance threshold R c 0. Determine the contact pressure test range Prange = [30g, 70g] (covering the effective pressure range of conventional patch fixtures). Based on the contact pressure test range Prange, select pressure points P1, P2, ..., Pn (n = (70-30) / 5+1 = 9 pressure points) in 5g increments. Collect the contact resistance Rn corresponding to each pressure point using a micro-ohmmeter. c 1. R c 2、…、R c Based on the collected pressure-contact resistance data, the expression formula of the Rc-pressure correspondence model is established using a linear fitting algorithm. Based on this model, the minimum pressure value satisfying that the contact pressure is less than or equal to the contact resistance threshold is calculated and taken as the optimal contact pressure Poptimal. Based on the optimal contact pressure Poptimal, the pressure adjustment component of the patch test fixture is adjusted, and the real-time contact resistance Rc is collected again. c Actual (first contact resistance), verify R c Real is less than or equal to R c 0, complete contact resistance co-calibration.

[0023] Furthermore, the pretreated sample is placed in a patch test fixture and fixed by vacuum adsorption. The contact pressure is adjusted to the optimal value, and the contact resistance is verified to be less than or equal to a preset threshold. Specifically, this includes: Based on the optimal contact pressure, obtain the drive current of the clamp pressure regulating component; Based on the driving current, a control signal is output to the clamp pressure regulating component to adjust the initial contact pressure to the optimal contact pressure. Obtain the vacuum adsorption system parameters of the fixture, preset the adsorption negative pressure threshold, start the vacuum adsorption device, and collect the real-time adsorption pressure; Based on the judgment result that the real-time adsorption pressure is less than or equal to the adsorption negative pressure threshold, the sample is preliminarily fixed. Obtain the image of the sample position after initial fixation, and determine the offset Δx and Δy between the sample center and the center of the fixture test position. If Δx ≤ 0.1 mm and Δy ≤ 0.1 mm, the position is deemed qualified; otherwise, the position of the adsorption platform is finely adjusted. After obtaining the result of the position being deemed qualified, the real-time contact resistance is collected again to obtain the second contact resistance; Based on the verification results that the second contact resistance is less than or equal to the contact resistance threshold, it is confirmed that the sample is clamped and fixed in one go. The formula for calculating the drive current of the clamp pressure regulating component is as follows: In the formula, This is the pressure-to-current conversion factor. For driving current, The optimal contact pressure is [the pressure required to achieve this].

[0024] Specifically, The pressure-to-current conversion coefficient ranges from 0.02 to 0.03 A / g. Based on the driving current, a control signal is output to the clamp pressure adjustment component to adjust the initial contact pressure to the optimal contact pressure, with an allowable error within ±5%. The vacuum adsorption system parameters of the clamp are obtained, with a preset adsorption negative pressure threshold of -60 kPa to ensure no sample displacement.

[0025] Furthermore, the initial capacitance, initial loss, and initial equivalent series resistance of the sample are obtained, specifically including: Determine the LCR test frequency based on the rated capacitance of the surface-mount aluminum electrolytic capacitor; Set the test voltage according to the LCR test frequency; Based on the LCR test frequency and test voltage, the initial impedance signal of the sample is acquired and decomposed to obtain the resistive and reactive components. The initial capacitance is determined by the reactance component; The initial loss is determined based on the resistive component and the initial capacitance, combined with the test frequency (LCR test frequency). Based on the LCR test frequency, switch to ESR test mode to collect the real-time equivalent series resistance of the sample; The difference between the real-time equivalent series resistance and the first contact resistance is used as the initial equivalent series resistance. The formula for calculating the initial capacitance is as follows: In the formula, For the initial capacitance, This is the reactance component; The formula for calculating the initial loss is: In the formula, For initial losses, For resistance components, This is the initial capacitance.

[0026] Specifically, the LCR test frequency is determined based on the rated capacitance of the surface-mount aluminum electrolytic capacitor. The LCR test frequency is 1 kHz when the rated capacitance is less than or equal to 10 μF, and 100 kHz when the rated capacitance is less than 10 μF, to match the testing accuracy requirements of samples with different capacitance values. The initial equivalent series resistance needs to be verified to be within the range of 0.8 × ESR rating to 1.2 × ESR rating to ensure the validity of the acquired data.

[0027] Further, the sample discharge is further completed, and the initial stable leakage current is collected, specifically including: After the high-frequency LCR module test is completed, the discharge module is started, and the discharge resistance is set; The rated voltage of the sample is obtained, and a discharge time threshold is determined; The working time of the discharge module is controlled to be greater than or equal to the discharge time threshold, and the residual voltage of the sample after discharge is collected; When the residual voltage is less than or equal to 0.05 times the rated voltage, it is confirmed that the discharge is completed; Based on the rated voltage of the sample, the leakage current test voltage is set; Based on the leakage current test voltage, the voltage is slowly applied through the leakage current module, and the stable leakage current is collected after the voltage is maintained for a predetermined duration; The value of the stable leakage current is verified to be within the range of 0 to the rated value of the stable leakage current, thereby determining the initial stable leakage current.

[0028] Specifically, the discharge resistance Rdis set to 1kΩ to avoid damage to the sample due to excessive discharge current, wherein the discharge time threshold tis set to 3×U×C / R, U is the rated voltage of the sample, and C is the rated capacitance. The rated value range of the stable leakage current Iis 0.01×C×U+1μA.

[0029] Further, the real-time environmental temperature and humidity are collected, and the correction coefficient library is called to dynamically correct the initial capacitance, initial loss, initial equivalent series resistance, and initial stable leakage current of the sample, to obtain the standard capacitance, standard loss, standard equivalent series resistance, and standard stable leakage current of the sample, specifically including: The real-time environmental temperature and real-time relative humidity are collected using the temperature and humidity sensor integrated in the test platform; The temperature correction coefficient and humidity correction coefficient corresponding to the initial capacitance, initial loss, initial equivalent series resistance, and initial stable leakage current are obtained through the pre-constructed correction coefficient library; Based on the real-time environmental temperature, the initial capacitance, and the temperature correction coefficient corresponding thereto, the initial capacitance is calibrated to obtain the standard capacitance; Based on the real-time environmental temperature, the initial loss, and the temperature correction coefficient corresponding thereto, the corrected loss is obtained as the standard loss; Based on the real-time environmental temperature, the initial equivalent series resistance, and the temperature correction coefficient corresponding thereto, the corrected standard equivalent series resistance is obtained; Based on the real-time relative humidity, the initial stable leakage current, and the humidity correction coefficient corresponding thereto, the corrected standard stable leakage current is obtained.

[0030] Specifically, the standard capacitance = initial capacitance x [1 + b x (T - 25)] (25℃ is the standard temperature, and b is the temperature correction coefficient corresponding to the initial capacitance); the standard loss = initial loss x [1 + c x (T - 25)], c is the temperature correction coefficient corresponding to the initial loss; the standard equivalent series resistance = initial equivalent series resistance x [1 + a x (T - 25)], a is the temperature correction coefficient corresponding to the initial equivalent series resistance; the standard stable leakage current = initial stable leakage current x [1 + d x (RH - 45)] (45%RH is the standard humidity, and d is the humidity correction coefficient corresponding to the initial stable leakage current). Then the corrected four parameter values (standard capacitance, standard loss, standard equivalent series resistance and standard stable leakage current) need to be replaced by the measured values (initial capacitance, initial loss, initial equivalent series resistance, initial stable leakage current) for subsequent determination.

[0031] It can be understood that the pre-constructed correction coefficient library is constructed around the "environmental parameter (temperature and humidity) on the four parameters (capacitance, loss, equivalent series resistance ESR, leakage current) of the patch aluminum electrolytic capacitor", through the "sample selection-experimental design-data acquisition-model fitting-verification optimization" five-step process, to form a corresponding relationship library of "environmental parameters-correction coefficients" that can be directly called, to ensure the accuracy and reliability of dynamic correction. The construction process first needs to clarify that the correction object is capacitance, loss, ESR, and leakage current, and the environmental impact factors focus on temperature (T) and relative humidity (RH); select patch aluminum electrolytic capacitor samples covering different specifications (including common rated capacity, voltage, and package size), to ensure sample representativeness and avoid coefficient limitations caused by a single specification. Then build a constant temperature and humidity test chamber, set temperature gradient (covering actual application scenarios, such as -40℃~125℃, with 5℃~10℃ steps), humidity gradient (20%RH~90%RH, with 10%RH steps); for each sample, first measure the baseline parameters (Cbase, tanδbase, ESRbase, I_Lbase) under "standard environment (25℃, 45%RH)", then measure the corresponding parameters (Creal, tanδreal, ESRreal, I_Lreal) under each temperature and humidity combination, repeat the test 3 times at each temperature and humidity point to take the average value and reduce random errors. Then for each sample's four parameters, calculate the "measured value and baseline value deviation rate" under different temperature and humidity, such as temperature on capacitance deviation rate ΔC_T%=(Creal-Cbase) / Cbase×100%, humidity on leakage current deviation rate ΔI_L_RH%=(I_Lreal-I_Lbase) / I_Lbase×100%; aggregate all sample deviation rate data, eliminate outliers (such as data exceeding 3 times the standard deviation), to ensure data effectiveness. Then based on the processed data, establish a "environmental parameter-deviation rate" linear / non-linear fitting model according to the parameter type, to solve the correction coefficient: temperature correction coefficient (a, b, c): for ESR, capacitance, and loss, fit Δparameter%=coefficient×(T-25), solve the coefficient (such as a is the temperature coefficient of ESR, b is the temperature coefficient of capacitance); humidity correction coefficient (d): for leakage current, fit ΔI_L%=d×(RH-45), solve d; finally get the unified correction coefficient (such as a=-0.008 / ℃, b=-0.001 / ℃, c=-0.002 / ℃, d=0.02 / %RH), form the coefficient library basic data. Finally, select new samples that did not participate in the experiment, test the parameters under any non-standard temperature and humidity, and compare the "corrected value and baseline value under standard environment" after correction with the coefficients in the coefficient library; if the deviation exceeds the allowed range (such as ±2%), supplement the experimental data of the corresponding temperature and humidity interval, optimize the fitting model and coefficient, and iterate repeatedly until the correction accuracy meets the test requirements, to finally form a pre-constructed correction coefficient library that can be stably called.

[0032] Furthermore, a single-parameter compliance assessment is performed on the standard capacitance, standard loss, standard equivalent series resistance, and standard stable leakage current of the samples, specifically including: From the datasheet of the surface-mount aluminum electrolytic capacitor, obtain the single-parameter qualified thresholds for capacitance, loss, equivalent series resistance and stable leakage current in sequence. Further determine the capacitance deviation threshold, loss threshold, equivalent series resistance threshold, and leakage current threshold; Based on the corrected standard capacitance, standard loss, standard equivalent series resistance, and standard stable leakage current, the capacitance deviation rate and the equivalent series resistance deviation rate are determined respectively. Further determine whether the capacitance deviation rate is within the capacitance deviation threshold range, whether the standard loss is less than or equal to the loss threshold, whether the standard equivalent series resistance is within the equivalent series resistance threshold range, and whether the standard stable leakage current is less than or equal to the leakage current threshold, and simultaneously obtain the first judgment result of the single parameter. Based on the first judgment result of the single parameter, the standard capacitance, standard loss, standard equivalent series resistance or standard stable leakage current with values ​​between the first single parameter threshold and the second single parameter threshold are selected, and the parameter types close to the threshold are recorded. Based on the parameter type that is close to the threshold, the preset association threshold rule is invoked; Based on the correlation threshold rule, verify whether the other three parameters meet the requirements; If all individual parameters are qualified and the correlation verification is passed, the sample is deemed qualified. If all individual parameters are qualified but the correlation verification fails, the sample is determined to be potentially faulty. If any single parameter exceeds the threshold, the sample is deemed unqualified. The second determination result of the single parameter is further recorded, and the sample status is marked based on the second determination result of the single parameter.

[0033] Specifically, the capacitance deviation threshold is ±10% × rated capacitance, the loss threshold is 0.15, the equivalent series resistance threshold is 1.2 times the rated equivalent series resistance, the leakage current threshold is 1.2 × discharge time threshold, the capacitance deviation rate is (standard capacitance - rated capacitance) / rated capacitance × 100%, and the equivalent series resistance deviation rate is (standard equivalent series resistance - rated equivalent series resistance) / rated equivalent series resistance × 100%. The preset association threshold rules are as follows: if the standard stable leakage current is within the range of 1.1 × rated stable leakage current to the range of rated stable leakage current, then the association threshold is standard loss ≤ 0.135 and standard equivalent series resistance ≤ 1.1 × rated equivalent series resistance; if the standard equivalent series resistance is within the range of 1.1 × rated equivalent series resistance to 1.2 × rated equivalent series resistance, then the association threshold is capacitance deviation rate ≤ ±8% and standard stable leakage current ≤ 1.1 × rated stable leakage current.

[0034] Further, the parameters meeting the preset parameter threshold are subjected to correlation verification, and a determination result of sample qualification, potential failure or disqualification is output, specifically including: Based on the second determination result of the single parameter, the sample is divided into three categories of qualified, potential failure and unqualified; The standard capacitance, standard loss, standard equivalent series resistance and standard stable leakage current of the qualified sample are obtained, the sample model, test time, environmental parameter and contact resistance are recorded, and a single sample test report is generated in tabular format; The label of the potential failure sample is obtained, and a retest prompt signal is output to clearly indicate the parameters that need to be retested and the reasons for the failure of the correlation verification; The parameter values of the potential failure sample after retest are obtained, the dynamic correction and qualification determination process is repeated, and the sample state is updated; The test report and state of all samples are recorded, and a batch test summary report is generated, including the number of qualified, unqualified and potential failure, and the statistical distribution of key parameters.

[0035] Further, a patch aluminum electrolytic capacitor testing device is provided for implementing any of the above testing methods, comprising: A pad cleaning pretreatment module is used to clean the pads of the patch aluminum electrolytic capacitor, remove the oxide layer and residual solder paste, and obtain the pad cleanliness; A contact resistance calibration module is used to obtain the rated equivalent series resistance of the sample and determine the contact resistance threshold, collect contact resistance data under different contact pressures, establish an Rc-pressure corresponding model, and match the optimal contact pressure; A sample clamping and fixing module is used to place the pretreated sample into a patch test fixture, fix it by vacuum adsorption, adjust the contact pressure to the optimal value, and verify that the contact resistance is less than or equal to the preset threshold; An initial parameter acquisition and discharge module is used to first acquire the initial capacitance, initial loss and initial equivalent series resistance of the sample, further complete sample discharge, and collect the initial stable leakage current; An environmental adaptive correction module is used to collect the environmental temperature and humidity in real time, call the correction coefficient library to dynamically correct the initial capacitance, initial loss, initial equivalent series resistance and initial stable leakage current of the sample, and obtain the standard capacitance, standard loss, standard equivalent series resistance and standard stable leakage current of the sample; The eligibility determination module is used for performing single-parameter eligibility determination on the standard capacitance, standard loss, standard equivalent series resistance and standard stable leakage current of the sample, starting associated verification on the parameters meeting the preset parameter threshold, and outputting a determination result of sample eligibility, potential failure or unqualification.

[0036] The advantages of the present application are as follows: firstly, targeted elimination of test interference, targeted to the characteristics of the patch capacitor without external pin, through phased pad cleaning (based on residual area ratio evaluation for secondary cleaning) to ensure that the pad is free of impurities, combined with Rc-pressure model to match the optimal contact pressure and verify, reduce the interference of pad pollution and parasitic contact resistance on parameters, lay the foundation for test accuracy. Secondly, improve the reliability of parameter test and determination, first eliminate the influence of residual voltage on leakage current by discharging, then dynamically correct the parameters by calling the correction coefficient library according to real-time temperature and humidity, avoid data drift caused by non-standard environment; innovatively adopt the mode of "single parameter determination + associated verification", verify the associated parameters for parameters close to the threshold (such as leakage current, ESR), reduce the missed judgment of multi-parameter linkage failure. Thirdly, the device and method are highly adaptable, and the six modules form a "pretreatment-calibration-clamping-collection-correction-determination" closed loop, each link contains a verification step (such as verifying position offset after clamping, contact resistance), ensuring test repeatability, suitable for factory and incoming inspection, providing an efficient and standardized solution for patch capacitor quality control.

[0037] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above embodiments, and the above embodiments and descriptions in the specification are only the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection required by the present application is defined by the appended claims and their equivalents.

Claims

1. A method of testing a chip aluminum electrolytic capacitor, characterized by, The method comprises the following steps: Cleaning the pads of the aluminum electrolytic capacitor, removing the oxide layer and residual solder paste, and obtaining the cleanliness of the pads; Obtaining the rated equivalent series resistance of the sample, determining the contact resistance threshold, collecting the contact resistance data under different contact pressures, establishing the Rc-pressure corresponding model, and matching the optimal contact pressure; Place the pretreated sample into the patch test fixture, fix it by vacuum suction, adjust the contact pressure to the optimal value, and verify that the contact resistance is less than or equal to the preset threshold; First, obtain the initial capacitance, initial loss, and initial equivalent series resistance of the sample, further complete the sample discharge, and collect the initial stable leakage current; Real-time collection of environmental temperature and humidity, calling the correction coefficient library to dynamically correct the initial capacitance, initial loss, initial equivalent series resistance, and initial stable leakage current of the sample, and obtaining the standard capacitance, standard loss, standard equivalent series resistance, and standard stable leakage current of the sample; Perform single-parameter qualification judgment on the standard capacitance, standard loss, standard equivalent series resistance, and standard stable leakage current of the sample, and then start associated verification on the parameters that meet the preset parameter threshold, and output the judgment result of sample qualification, potential failure or unqualified.

2. The method of testing a chip aluminum electrolytic capacitor of claim 1, wherein, The method for cleaning the pads of the aluminum electrolytic capacitor, removing the oxide layer and residual solder paste, and obtaining the cleanliness of the pads comprises the following steps: Obtain the model specification of the aluminum electrolytic capacitor, determine the length and width of the pad, and further determine the pad area; Based on the pad area, determine the power and cleaning time of the ultrasonic cleaning tool; Start the ultrasonic cleaning tool to clean the pad for the first time; Obtain the pad image after the first cleaning, and further determine the residual area of the pad oxide layer; According to the ratio of the residual area to the pad area, obtain the secondary cleaning evaluation value; Set the secondary cleaning evaluation threshold, and determine whether secondary cleaning is needed. If the secondary cleaning evaluation value is greater than the secondary cleaning evaluation threshold, perform secondary cleaning. If the secondary cleaning evaluation value is less than or equal to the secondary cleaning evaluation threshold, stop cleaning; Determine the final cleaned pad image, again obtain the residual area ratio, and obtain the pad cleanliness; If the pad cleanliness is greater than or equal to the pad cleanliness threshold, the sample pretreatment is completed; The calculation formula of the power and cleaning time of the ultrasonic cleaning tool is: wherein is the power of the ultrasonic cleaning tool, is the pad area, is the cleaning time of the ultrasonic cleaning tool, is the cleaning power coefficient, is the cleaning time coefficient; The calculation formula of the pad cleanliness is: In the formula, is the pad cleanliness, is the residual area ratio of the pad image after final cleaning.

3. The method of testing a chip aluminum electrolytic capacitor of claim 1, wherein, The method for obtaining the rated equivalent series resistance of the sample, determining the contact resistance threshold, collecting the contact resistance data under different contact pressures, establishing the Rc-pressure corresponding model, and matching the optimal contact pressure comprises the following steps: Based on the rated equivalent series resistance of the aluminum electrolytic capacitor, obtain the contact resistance threshold; Determine the test range of the contact pressure through the contact resistance threshold; Based on the test range of the contact pressure, select the pressure points at the preset step interval, collect the contact resistance corresponding to each pressure point through the micro-ohm meter, and obtain the pressure-contact resistance data; According to the pressure-contact resistance data, establish the Rc-pressure corresponding model; Through the Rc-pressure corresponding model, solve the minimum pressure value that satisfies the contact pressure less than or equal to the contact resistance threshold, as the optimal contact pressure; According to the optimal contact pressure, the pressure adjusting assembly of the patch test fixture is adjusted, the real-time contact resistance is collected again to obtain a first contact resistance, it is verified that the first contact resistance is less than or equal to the contact resistance threshold, and the contact resistance cooperative calibration is completed; The expression formula of the Rc-pressure corresponding model is: wherein is the contact resistance, is the contact pressure, is the fitted slope, is the fitted intercept.

4. The method of testing a chip aluminum electrolytic capacitor of claim 1, wherein The pre-processed sample is placed into the patch test fixture, fixed by vacuum adsorption, the contact pressure is adjusted to the optimal value, and it is verified that the contact resistance is less than or equal to the preset threshold, and the specific steps include: According to the optimal contact pressure, the driving current of the clamp pressure adjusting assembly is obtained; Based on the driving current, a control signal is output to the clamp pressure adjusting assembly to adjust the initial contact pressure to the optimal contact pressure; The vacuum adsorption system parameters of the clamp are obtained, the adsorption negative pressure threshold is preset, the vacuum adsorption device is started, and the real-time adsorption pressure is collected; Based on the determination result that the real-time adsorption pressure is less than or equal to the adsorption negative pressure threshold, the sample is preliminarily fixed; The position image of the preliminarily fixed sample is obtained, the offset Δx, Δy of the sample center and the fixture test center is determined, if Δx≤0.1mm and Δy≤0.1mm, the position is qualified, otherwise the adsorption platform position is fine-tuned; The determination result of the position qualified is obtained, the real-time contact resistance is collected again to obtain a second contact resistance; Based on the verification result that the second contact resistance is less than or equal to the contact resistance threshold, it is confirmed that the sample is once clamped and fixed; The calculation formula of the driving current of the clamp pressure adjusting assembly is: wherein is the pressure-current conversion factor, is the drive current, is the optimal contact pressure.

5. The method of testing a patch aluminum electrolytic capacitor of claim 3, wherein, The initial capacitance, initial loss and initial equivalent series resistance of the sample are obtained, and the specific steps include: Based on the rated capacitance of the patch aluminum electrolytic capacitor, the LCR test frequency is determined; According to the LCR test frequency, the test voltage is set; Based on the LCR test frequency and the test voltage, the initial impedance signal of the sample is collected, and the resistance component and the reactance component are obtained by decomposition; The initial capacitance is determined through the reactance component; Based on the resistance component and the initial capacitance, the initial loss is determined in combination with the test frequency LCR test frequency; Based on the LCR test frequency, the ESR test mode is switched to, and the real-time equivalent series resistance of the sample is collected; The difference between the real-time equivalent series resistance and the first contact resistance is taken as the initial equivalent series resistance; The calculation formula of the initial capacitance is: wherein is the initial capacitance, is the reactance component; The calculation formula of the initial loss is: wherein is the initial loss, is the resistance component, is the initial capacitance.

6. The method of testing a patch aluminum electrolytic capacitor of claim 1, wherein, The sample is further discharged, and the initial stable leakage current is collected, and the specific steps include: After the high-frequency LCR module test is completed, the discharge module is started, and the discharge resistance is set; The rated voltage of the sample is obtained, and the discharge time threshold is determined; The working time of the discharge module is controlled to be greater than or equal to the discharge time threshold, and the residual voltage of the sample after discharge is collected; When the residual voltage is less than or equal to 0.05 times the rated voltage, it is confirmed that the discharge is completed; Based on the rated voltage of the sample, the leakage current test voltage is set; Based on the leakage current test voltage, the voltage is slowly applied through the leakage current module, and the stable leakage current is collected after the voltage is maintained for a preset duration; It is verified that the value of the stable leakage current is within the range of 0 to the rated value of the stable leakage current, so as to determine the initial stable leakage current.

7. The method of testing a patch aluminum electrolytic capacitor of claim 1, wherein, The real-time environment temperature and humidity are collected, and the initial capacitance, initial loss, initial equivalent series resistance and initial stable leakage current of the sample are dynamically corrected by calling the correction coefficient library, to obtain the standard capacitance, standard loss, standard equivalent series resistance and standard stable leakage current of the sample, specifically including: The real-time environment temperature and humidity are collected, and the initial capacitance, initial loss, initial equivalent series resistance and initial stable leakage current of the sample are dynamically corrected by calling the correction coefficient library, to obtain the standard capacitance, standard loss, standard equivalent series resistance and standard stable leakage current of the sample, specifically including: The real-time environment temperature and humidity are collected, and the initial capacitance, initial loss, initial equivalent series resistance and initial stable leakage current of the sample are dynamically corrected by calling the correction coefficient library, to obtain the standard capacitance, standard loss, standard equivalent series resistance and standard stable leakage current of the sample, specifically including: The real-time environment temperature and humidity are collected, and the initial capacitance, initial loss, initial equivalent series resistance and initial stable leakage current of the sample are dynamically corrected by calling the correction coefficient library, to obtain the standard capacitance, standard loss, standard equivalent series resistance and standard stable leakage current of the sample, specifically including: The real-time environment temperature and humidity are collected, and the initial capacitance, initial loss, initial equivalent series resistance and initial stable leakage current of the sample are dynamically corrected by calling the correction coefficient library, to obtain the standard capacitance, standard loss, standard equivalent series resistance and standard stable leakage current of the sample, specifically including: The real-time environment temperature and humidity are collected, and the initial capacitance, initial loss, initial equivalent series resistance and initial stable leakage current of the sample are dynamically corrected by calling the correction coefficient library, to obtain the standard capacitance, standard loss, standard equivalent series resistance and standard stable leakage current of the sample, specifically including: The standard capacitance, standard loss, standard equivalent series resistance and standard stable leakage current of the sample are subjected to single-parameter eligibility determination, specifically including:

8. The method of testing a patch aluminum electrolytic capacitor of claim 1, wherein, The single-parameter eligibility threshold values of capacitance, loss, equivalent series resistance and stable leakage current are sequentially obtained from the specification book of the aluminum electrolytic capacitor; The capacitance deviation threshold value, loss threshold value, equivalent series resistance threshold value and leakage current threshold value are further determined; Based on the corrected standard capacitance, standard loss, standard equivalent series resistance and standard stable leakage current, the capacitance deviation rate and equivalent series resistance deviation rate are determined respectively; It is further judged whether the capacitance deviation rate is within the capacitance deviation threshold value, whether the standard loss is less than or equal to the loss threshold value, whether the standard equivalent series resistance is within the equivalent series resistance threshold value, and whether the standard stable leakage current is less than or equal to the leakage current threshold value, and the single-parameter first determination result is synchronously obtained; Based on the single-parameter first determination result, the standard capacitance, standard loss, standard equivalent series resistance or standard stable leakage current with values between the first single-parameter threshold value and the second single-parameter threshold value are screened out, and the parameter type close to the threshold value is recorded; Based on the parameter type close to the threshold value, the preset associated threshold value rule is called; Based on the associated threshold value rule, it is checked whether the other three parameters meet the requirements; If all single parameters are qualified and the associated check passes, the sample is determined to be qualified; If all single parameters are qualified but the associated check does not pass, the sample is determined to be potentially failed; If any single parameter exceeds the threshold value, the sample is determined to be unqualified; The single-parameter second determination result is further recorded, and based on the single-parameter second determination result, the sample state is marked. The parameters meeting the preset parameter threshold value are subjected to associated check, and the determination result of sample qualification, potential failure or unqualification is output, specifically including:

9. The method of testing a patch aluminum electrolytic capacitor of claim 8, wherein, Based on the single-parameter second determination result, the sample is divided into three categories: qualified, potentially failed and unqualified; ​ Obtain the standard capacitance, standard loss, standard equivalent series resistance and standard stable leakage current of the qualified sample, record the sample model, test time, environmental parameters, contact resistance, and generate a single sample test report in tabular format; Obtain the label of the potential failure sample, output a retest prompt signal, and specify the parameters that need to be retested and the reasons for the associated verification failure; Obtain the parameter values of the potential failure sample after retesting, repeat the dynamic correction and qualification judgment process, and update the sample status; Record all sample test reports and status, generate a batch test summary report, including the number of qualified, unqualified, potential failure, and key parameter statistical distribution.

10. A patch aluminum electrolytic capacitor testing apparatus for implementing the testing method according to any one of claims 1 to 9, characterized in that, It includes: Pad cleaning pretreatment module, the pad cleaning pretreatment module is used for cleaning the pads of the patch aluminum electrolytic capacitor, removing the oxide layer and residual solder paste, and obtaining the pad cleanliness; Contact resistance calibration module, the contact resistance calibration module is used for obtaining the rated equivalent series resistance of the sample and determining the contact resistance threshold, collecting contact resistance data under different contact pressures, establishing an Rc-pressure corresponding model, and matching the optimal contact pressure; Sample clamping and fixing module, the sample clamping and fixing module is used for placing the pretreated sample into the patch test fixture, fixing it by vacuum adsorption, adjusting the contact pressure to the optimal value, and verifying that the contact resistance is less than or equal to the preset threshold; Initial parameter acquisition and discharge module, the initial parameter acquisition and discharge module is used for first obtaining the initial capacitance, initial loss and initial equivalent series resistance of the sample, further completing sample discharge, and collecting the initial stable leakage current; Environment adaptive correction module, the environment adaptive correction module is used for real-time collection of environmental temperature and humidity, calling a correction coefficient library to dynamically correct the initial capacitance, initial loss, initial equivalent series resistance and initial stable leakage current of the sample, and obtaining the standard capacitance, standard loss, standard equivalent series resistance and standard stable leakage current of the sample; Qualification judgment module, the qualification judgment module is used for single parameter qualification judgment of the standard capacitance, standard loss, standard equivalent series resistance and standard stable leakage current of the sample, and associated verification of the parameters meeting the preset parameter threshold, and output of the qualification, potential failure or unqualified judgment result of the sample.

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