A circuit board parameter automatic test method and system

Abstract

The present application relates to the technical field of circuit test, in particular to a kind of circuit board parameter automation test method and system, comprising: iteratively increase the set temperature of high-low temperature chamber, and exert load to circuit board, based on the difference between the temperature corresponding to component after exerting load, screen out main component, to any main component is heated independently to obtain independent temperature, and obtain the working voltage of main component under independent temperature, based on the change of working voltage of main component under all independent temperatures, obtain several voltage change rate data segments, linear fitting is established in conjunction with each voltage change rate data segment Temperature-voltage correction model of each component in circuit board, the temperature-voltage correction model of component in circuit board is used to carry out circuit board parameter test.The present application effectively improves the efficiency and accuracy of circuit board parameter test.

Description

Technical Field

[0001] This invention relates to the field of circuit testing technology, and more specifically to an automated testing method and system for circuit board parameters. Background Technology

[0002] As a crucial component of modern electronic products, circuit boards (PCBs) directly impact product quality and functionality through their performance and reliability. Therefore, PCB performance testing is an essential task. With continuous technological advancements, PCBs are becoming increasingly complex and integrated, placing higher demands on their testing and inspection. For example, testing parameters that directly affect PCB performance is of great significance for improving the quality and competitiveness of electronic products.

[0003] When testing components on a circuit board, the components generate heat during operation, causing their temperatures to change. The parameters of the components are affected by temperature, leading to deviations in the results obtained by directly testing the parameters. Therefore, temperature correction is required. At the same time, different components have different temperatures, and the temperatures of the components have mutual influence relationships. This means that the results of directly testing all components are affected by different temperatures, making it difficult to correct directly. Summary of the Invention

[0004] This invention provides an automated testing method and system for circuit board parameters to solve existing problems.

[0005] The automated testing method and system for circuit board parameters of the present invention adopts the following technical solution:

[0006] One embodiment of the present invention provides an automated testing method for circuit board parameters, the method comprising the following steps:

[0007] A circuit board mounting test device is provided, the test device including a high and low temperature chamber, a miniature heating element, a thermocouple, an infrared imager, and a temperature controller;

[0008] The set temperature of the high and low temperature chamber is increased iteratively, and a load is applied to the circuit board. Based on the difference between the corresponding temperatures of the components in the circuit board after the load is applied, several key components are selected.

[0009] By using a micro heating element with iteratively increasing temperature, any major component can be individually heated to obtain several independent temperatures of the major component, and the operating voltage of the major component at each independent temperature can be obtained.

[0010] Based on the changes in the operating voltage of the main components under all independent temperatures, several voltage change rate data segments are obtained. Combining the linear fitting of each voltage change rate data segment, a temperature-voltage correction model for each component in the circuit board is established.

[0011] Circuit board parameter testing is performed using a temperature-voltage correction model for components in the circuit board.

[0012] Furthermore, the iteration increases the set temperature of the high and low temperature chamber and applies a load to the circuit board. Based on the temperature differences between the components on the circuit board after the load is applied, several key components are selected. The specific method includes:

[0013] The initial temperature of the high and low temperature chamber is preset, and the initial temperature is iteratively increased to obtain several test temperature conditions. The temperature of each component in the circuit board under different test temperature conditions is obtained by an infrared imager. Based on the difference between the corresponding temperatures of different components under any test temperature conditions, the relative temperature of the components is obtained.

[0014] Based on the similarity of the relative temperatures of different components under all test temperature conditions, several key components are selected from all components.

[0015] Furthermore, the specific method for obtaining the relative temperature is as follows:

[0016] The initial temperature of the high and low temperature chamber is preset, and the temperature set for the high and low temperature chamber is used as the test temperature condition. The circuit board is placed in the high and low temperature chamber to provide a load to the circuit board and simulate the real operation of the circuit board.

[0017] Infrared images of the circuit board are acquired using an infrared imager located directly above the circuit board. Several components are identified in the infrared images of the circuit board using the YOLO algorithm, and the temperature of all components is obtained. Any component is taken as the target component, and the absolute value of the temperature difference between the target component and each other component is obtained as the temperature deviation between the target component and other components. The average temperature deviation between the target component and all other components is obtained as the relative temperature of the target component.

[0018] According to the preset step size The temperature inside the high and low temperature chamber is gradually increased to obtain several test temperature conditions, and the relative temperature of the target components on the circuit board is obtained under each test temperature condition.

[0019] Furthermore, the method for selecting several key components from all components based on the similarity of their relative temperatures under all test temperature conditions includes:

[0020] Obtain the relative temperature of any component under all test temperature conditions in the high and low temperature chamber, and sort the relative temperatures of the component under all test temperature conditions in ascending order of the corresponding values ​​to obtain the relative temperature sequence of the component.

[0021] The cosine similarity between the relative temperature sequences of any two components is used as the distance metric for the mean-shift clustering algorithm, thereby clustering all components on the circuit board to obtain several component clusters.

[0022] In any component cluster, the component that is closest to the cluster center of the component cluster is taken as the main component.

[0023] Furthermore, the method of individually heating any major component using a micro heating element with iteratively increasing temperature to obtain several independent temperatures for the major component, and obtaining the operating voltage of the major component at each independent temperature, includes the following specific methods:

[0024] For any major component, a miniature heating element is attached to the surface of the major component with thermally conductive adhesive, and the lead wire of the miniature heating element is connected to the temperature controller; then, a thermocouple is attached to the other end of the major component with thermally conductive adhesive, so that the thermocouple and the miniature heating element are symmetrically positioned, the major component is heated by the miniature heating element, and the temperature of the major component is measured by the thermocouple.

[0025] The test temperature is controlled by a high and low temperature chamber to a preset initial temperature. During the heating of the main components by the micro heating element, the temperature of the main components is collected by thermocouples. The temperature of the main components collected by thermocouples is recorded as the independent temperature of the main components. When the absolute value of the difference between the independent temperature of the main components and the initial temperature is less than or equal to a preset difference threshold, the operating voltage of the main components at the corresponding independent temperature is obtained.

[0026] In the process of heating the main components using a miniature heating element, the temperature increment step of the miniature heating element is calculated based on the voltage change of the main components. The heating temperature of the miniature heating element is iteratively increased by the temperature increment step to obtain the operating voltage of the main components at several independent temperatures.

[0027] Furthermore, the specific method for obtaining the temperature increment step size is as follows:

[0028] The preset temperature step factor is used to obtain the independent temperature of any major component when heating it with a micro heating element. When the independent temperature rise of the major component is equal to the temperature compensation factor, the parameter change coefficient of the major component is calculated based on the voltage change of the major component.

[0029] The independent temperature corresponding to each time the parameter change coefficient of the main component is greater than or equal to the preset parameter change threshold is obtained, and is used as the corresponding conditional independent temperature. The difference between the current conditional independent temperature and the previous conditional independent temperature of the main component is used as the temperature increment step.

[0030] Furthermore, the method for obtaining several voltage change rate data segments based on the changes in the operating voltage of the main components at all independent temperatures includes:

[0031] For any major component, the operating voltage of the major component at all independent temperatures is sorted in descending order of the corresponding independent temperatures, and the resulting sequence data is recorded as the operating voltage sequence of the major component. The operating voltage sequence is curve-fitted using the least squares method, and the rate of change of the operating voltage at each independent temperature in the curve fitting result is obtained. The sequence formed by the rate of change of the operating voltage at all independent temperatures is recorded as the voltage change rate sequence of the major component.

[0032] Mean-shift clustering is used to cluster all elements in the voltage change rate sequence to obtain several clusters. The data segments formed by the elements contained in the clusters in the voltage change rate sequence are denoted as voltage change rate data segments, thus obtaining several voltage change rate data segments.

[0033] Furthermore, the specific method for establishing a temperature-voltage correction model for each component on the circuit board by combining the linear fitting results of each voltage change rate data segment includes:

[0034] The least squares method and a univariate linear regression model are used to fit a straight line to any voltage change rate data segment of any major component.

[0035] The root mean square error between the univariate linear regression model and the voltage change rate data segment during the linear fitting process of any voltage change rate data segment is obtained and denoted as the root mean square error of the fitting of the corresponding voltage change rate data segment. The slope and intercept of the linear fitting result of the corresponding voltage change rate data segment are obtained and denoted as the fitting slope and fitting result of the corresponding voltage change rate data segment. Combining the root mean square error, fitting slope and fitting intercept of all voltage change rate data segments of the main components, the linear model parameters of the main components are obtained. The linear model parameters include the slope coefficient and the intercept coefficient.

[0036] By utilizing the linear model parameters of the main components and combining them with their independent temperatures, a temperature-voltage correction model for the main components is established. This temperature-voltage correction model of the main components is also used as the temperature-voltage correction model for all components in the corresponding component cluster.

[0037] Furthermore, the specific method for testing circuit board parameters using the temperature-voltage correction model of components in the circuit board includes:

[0038] The operating voltage of any component at several independent temperatures is obtained and denoted as the test voltage of the component.

[0039] The independent temperature is used as the input to the temperature-voltage correction model of the component, and the correction voltage of the component is output by the temperature-voltage correction model.

[0040] The absolute value of the difference between the test voltage and the corresponding correction voltage of the component is recorded as the voltage deviation value of the component. When the voltage deviation value is greater than or equal to the preset voltage deviation threshold, the corresponding component is identified as an abnormal component.

[0041] An automated circuit board parameter testing system includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of any one of the automated circuit board parameter testing methods described above.

[0042] The beneficial effects of the technical solution of this invention are as follows: By gradually increasing the ambient temperature and applying a load, infrared imaging technology is used to capture the temperature distribution differences of various components on the circuit board under operating conditions, effectively identifying representative key components. Subsequently, micro heating elements are used to locally and controllably heat these key components independently, enabling the acquisition of operating voltage data of components at different temperature points without affecting other areas, thus improving the accuracy and flexibility of the test. By analyzing the voltage change trends at each independent temperature, multiple voltage change rate data segments are extracted, and combined with linear fitting methods, a temperature-adaptive voltage correction model is constructed, allowing the parameter performance of the circuit board under different temperature conditions to be accurately predicted and compensated. Finally, this model is applied to actual circuit board parameter testing, significantly improving the accuracy and environmental adaptability of the test results, and effectively improving the efficiency and accuracy of circuit board parameter testing. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 This is a flowchart of the steps of an automated circuit board parameter testing method according to the present invention;

[0045] Figure 2 This is a structural block diagram of an automated circuit board parameter testing system according to the present invention. Detailed Implementation

[0046] To further illustrate the technical means and effects adopted by the present invention to achieve its intended purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of an automated circuit board parameter testing method and system proposed according to the present invention. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0047] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0048] The following description, in conjunction with the accompanying drawings, details the specific scheme of the automated testing method and system for circuit board parameters provided by this invention.

[0049] Please see Figure 1 The diagram illustrates a flowchart of an automated circuit board parameter testing method according to an embodiment of the present invention, which includes the following steps:

[0050] Step S001: Install the test device on the circuit board.

[0051] It should be noted that during the automated testing of circuit board parameters, the parameters of components are affected by temperature. Therefore, the current automated testing mainly verifies the effect of temperature on component parameters, and then tests the component parameters at different temperatures to determine the parameter drift under the influence of temperature.

[0052] Specifically, in order to implement the automated testing method for circuit board parameters proposed in this embodiment, a testing device first needs to be installed on the circuit board. The specific process is as follows:

[0053] First, select equipment and sensors for circuit board parameter testing, specifically including:

[0054] High and low temperature chamber, used to provide a controllable temperature environment; Model: ESPEC SH-241, core parameters: temperature control range: -70℃-150℃; temperature control accuracy: ±0.5℃; temperature uniformity: ±1℃ (any point inside the chamber); heating rate: 5℃ / min (ensuring temperature stabilization speed); selection criteria: must cover the target range of -40℃-85℃, accuracy of ±0.5℃ can ensure temperature point deviation ≤±0.5℃, avoiding affecting the accuracy of the collected data.

[0055] Thermocouple, used to acquire the actual temperature of components; Model: Omega 5TC-TT-K-36-36; Core parameters: Temperature range: -200℃-1372℃; Accuracy: ±1℃ (-40℃-125℃); Response time: ≤1 second; Wire diameter: 0.25mm; Selection criteria: K-type thermocouples have good linearity in the range of -40℃-85℃, and the accuracy of ±1℃ meets the requirements for temperature difference measurement (maximum temperature difference of components is 18℃, and the error percentage is <6%).

[0056] Data acquisition card for synchronously acquiring multiple thermocouple temperature signals; Model: NI USB-6211; Core parameters: Analog input channels: 16; Resolution: 16-bit; Sampling rate: 250kS / s; Input range: ±10V (compatible with thermocouple signals); Synchronous sampling: Supported (ensures simultaneous acquisition of multiple channels); Selection criteria: 16-bit resolution corresponds to a minimum voltage of 0.3mV (±10V range), capable of resolving temperature differences of 0.1℃ (K-type thermocouple output 41μV / ℃, 0.3mV corresponds to 7.3℃, requiring an amplification module).

[0057] High-precision multimeter for measuring circuit output voltage; Model: Keysight 34461A; Core parameters: DC voltage measurement accuracy: ±0.0015% (10V range); Sampling rate: 100 times / second; Resolution: 1μV (10V range); Selection criteria: 0.0015% accuracy ensures that with a 10mV input, the output voltage measurement error is <0.15μV, corresponding to a gain error <0.000015 times, meeting the accuracy requirements.

[0058] Electronic load for simulating different load conditions; Model: IT8511; Core parameters: Current range: 0-3A; Adjustment accuracy: ±0.1%+5mA; Response time: <10ms; Selection criteria: Fast response time ensures that the component temperature does not change significantly when the load changes, thus ensuring the validity of the data.

[0059] Infrared imager, used to initially distinguish the temperature changes of different components; Model: FLIR E60; Core parameters: Resolution: 320×240 pixels; Temperature range: -20℃-120℃; Accuracy: ±2℃ or ±2%; Selection criteria: Non-contact temperature measurement, which can quickly locate the high-temperature area of ​​components.

[0060] Signal generator used to provide a stable input signal; Model: Rigol DG1022Z; Key parameters: Output voltage range: 0-10V; Frequency accuracy: ±1ppm; Distortion: <0.1% (1kHz); Selection criteria: Low distortion ensures a pure input signal and avoids harmonics affecting gain measurement.

[0061] Miniature heating device for localized heating of target components; Type: Miniature heating element, size 5mm×5mm, power 1W; Core parameters: Heating range: 25℃-150℃; Temperature accuracy: ±1℃; Control method: PID regulation; Adhesive type.

[0062] Then, the temperature of all components is obtained using an infrared imager; the temperature of individual components is obtained using thermocouples; and the operating voltage of the components is obtained using a multimeter.

[0063] Thus, the temperature and operating voltage of the components on the circuit board during the testing process were obtained using the above method.

[0064] Step S002: Iteratively increase the set temperature of the high and low temperature chamber and apply a load to the circuit board. Based on the difference between the corresponding temperatures of the components in the circuit board after the load is applied, select several key components.

[0065] It should be noted that during circuit board testing, temperature differences exist between components. This can cause the overall temperature correction to fail to meet the parameter deviations of individual components, resulting in poor final temperature correction. Therefore, in actual testing, it is necessary to perform individual temperature correction for different components. Furthermore, in practice, different components on a circuit board generate heat differently during testing; some components exhibit significant temperature deviations, while others show only minor deviations. To improve testing efficiency, components with larger temperature deviations can be isolated and tested separately.

[0066] Specifically, in step S201, the initial temperature of the high and low temperature chamber is preset, and the initial temperature is iteratively increased to obtain several test temperature conditions. The temperature of each component in the circuit board under different test temperature conditions is obtained by using an infrared imager. Based on the difference between the corresponding temperatures of different components under any test temperature conditions, the relative temperature of the components is obtained.

[0067] As a preferred embodiment, the method for obtaining the relative temperature includes:

[0068] First, the initial temperature of the high and low temperature chamber is preset, and the temperature set for the high and low temperature chamber is used as the test temperature condition. The circuit board is placed in the high and low temperature chamber to provide a load to the circuit board and simulate the real operation of the circuit board.

[0069] It should be noted that in this embodiment, the initial temperature is set to 25°C, and the temperature of the high and low temperature chamber is maintained at the initial temperature for more than 30 minutes before the test to simulate the normal temperature environment. This can be adjusted according to the actual situation, and this embodiment of the invention does not impose any specific limitations. In addition, in this embodiment of the invention, after providing a load to the circuit board, subsequent operations are started after the circuit board has been running for more than 10 minutes, so that the test results are more consistent with the normal operating state of the circuit board.

[0070] Then, an infrared image of the circuit board is acquired using an infrared imager located directly above the circuit board. The YOLO algorithm is used to identify several components in the infrared image of the circuit board and to acquire the temperature of all components. Any component is selected as the target component, and the absolute value of the temperature difference between the target component and each other component is acquired as the temperature deviation between the target component and other components. The average temperature deviation between the target component and all other components is acquired as the relative temperature of the target component.

[0071] It should be noted that the YOLO algorithm is an existing object detection and recognition algorithm, so it will not be described in detail in this invention.

[0072] Finally, according to the preset step size The temperature inside the high and low temperature chamber is gradually increased to obtain several test temperature conditions, and the relative temperature of the target components on the circuit board is obtained under each test temperature condition.

[0073] It should be noted that, in this embodiment of the invention, the temperature adjustment range of the high and low temperature chamber is 25℃-150℃; additionally, the preset step size is based on experience. The temperature is 5℃, but can be adjusted according to actual conditions. This embodiment of the invention does not impose specific limitations.

[0074] Step S202: Based on the similarity of the relative temperatures of different components under all test temperature conditions, select several key components from all components.

[0075] Components with the same temperature deviation characteristics under the same temperature environment have the same temperature correction logic. Therefore, in order to reduce the number of isolation and division results of components on the circuit board in the embodiments of the present invention, thereby reducing the testing workload, the embodiments of the present invention choose to classify components with large temperature deviations, and then select representative components from them.

[0076] In a specific embodiment of the present invention, the method for determining the main components is as follows:

[0077] First, the relative temperature of any component under all test temperature conditions in the high and low temperature chamber is obtained. Then, the relative temperatures of the components under all test temperature conditions are sorted in ascending order of the corresponding values ​​to obtain the relative temperature sequence of the components.

[0078] Then, the cosine similarity between the relative temperature sequences of any two components is used as the distance metric for the mean-shift clustering algorithm, thereby clustering all components on the circuit board to obtain several component clusters.

[0079] Finally, in any component cluster, the component that is closest to the cluster center of the component cluster is selected as the primary component.

[0080] It should be noted that, in the process of acquiring the main components, the classification of components with large temperature deviations is mainly based on their temperature differences under different temperature environments. Generally, under the same temperature environment, the more consistent the temperature deviations, the greater the probability that they belong to the same type of component. Then, among the same type of component, the smaller the temperature deviation of the component compared to other components, the greater the probability that it is a main component.

[0081] Thus, the main components are obtained through the above method.

[0082] Step S003: Individually heat any major component by using a micro heating element with iteratively increasing temperature to obtain several independent temperatures of the major component, and obtain the operating voltage of the major component at each independent temperature.

[0083] It should be noted that, based on the above steps, after identifying the main components, it is necessary to conduct isolation tests on the main components. The isolation test means that the main components are tested separately in the subsequent testing process to analyze their parameter performance at different temperatures, and then the corresponding temperature correction model is determined.

[0084] Specifically, in one specific embodiment of the present invention, the isolation test process is as follows:

[0085] First, for any main component, a miniature heating element is attached to the surface of the main component using thermally conductive adhesive, and the leads of the miniature heating element are connected to the temperature controller; then, a thermocouple is attached to the other end of the main component using thermally conductive adhesive, so that the thermocouple and the miniature heating element are symmetrically positioned, the main component is heated by the miniature heating element, and the temperature of the main component is measured by the thermocouple.

[0086] Then, the test temperature is controlled by a high and low temperature chamber to a preset initial temperature. During the heating of the main components by the micro heating element, the temperature of the main components is collected by a thermocouple. The temperature of the main components collected by the thermocouple is recorded as the independent temperature of the main components. When the absolute value of the difference between the independent temperature of the main components and the initial temperature is less than or equal to a preset difference threshold, the operating voltage of the main components at the corresponding independent temperature is obtained.

[0087] It should be noted that when collecting the temperature of the main components by thermocouple in this embodiment of the invention, the absolute value of the difference between the independent temperature collected within 30 consecutive minutes and the initial temperature must meet the condition of being less than or equal to a preset difference threshold. In addition, in this embodiment of the invention, the preset difference threshold is 0.3℃ based on experience. The continuous duration (i.e., the 30 minutes) and the difference threshold can be adjusted according to the actual situation. This embodiment of the invention does not impose specific limitations.

[0088] Finally, during the process of heating the main components using a micro heating element, the temperature increment step of the micro heating element is calculated based on the voltage changes of the main components. The heating temperature of the micro heating element is iteratively increased by the temperature increment step to obtain the operating voltage of the main components at several independent temperatures.

[0089] It should be noted that, in order to ensure that the test results obtained after individual testing of the main components can comprehensively reflect the influence of temperature changes on the component parameters, this embodiment of the invention uses a micro heating element to heat the main components. This allows for the rapid acquisition of the interaction between the operating voltage and independent temperature of the main components during energized operation. Furthermore, due to the thermal effect of the current under energized conditions, the independent temperature of the main components will gradually rise, resulting in a significant reduction in the effect of heating the main components at a relatively low temperature. Therefore, this embodiment of the invention also iteratively increases the heating temperature of the micro heating element by using a temperature increment step, so that the heating temperature of the micro heating element always follows the rising trend of the independent temperature of the main components when the voltage parameters change.

[0090] As an optional embodiment, the specific process of the temperature increase step is as follows:

[0091] First, a temperature step factor is preset. When any major component is heated by a micro heating element, the independent temperature of the major component is obtained. When the value of the independent temperature rise of the major component is equal to the value of the temperature compensation factor, the parameter change coefficient of the major component is calculated based on the voltage change of the major component.

[0092] It should be noted that, in the embodiments of the present invention, the temperature step factor is preset to 1°C based on experience, and can be adjusted according to the actual situation. The embodiments of the present invention do not impose specific limitations.

[0093] Then, obtain the independent temperature corresponding to each time the parameter change coefficient of the main component is greater than or equal to the preset parameter change threshold, and use it as the corresponding conditional independent temperature. The difference between the current conditional independent temperature and the previous conditional independent temperature of the main component is used as the temperature growth step.

[0094] As an optional embodiment, the specific calculation method of the parameter change coefficient is as follows: obtain the absolute value of the difference between the operating voltage of the main components before and after obtaining the independent temperature, and use it as the voltage change of the main components; In the formula Indicates the parameter variation coefficient of the main components; This indicates the voltage change of the main components. This represents the average of all voltage changes of the main components throughout the entire test process.

[0095] Thus, the operating voltages of the main components at several independent temperatures are obtained through the above method.

[0096] Step S004: Based on the changes in the operating voltage of the main components under all independent temperatures, several voltage change rate data segments are obtained. Combining the linear fitting of each voltage change rate data segment, a temperature-voltage correction model for each component in the circuit board is established.

[0097] It should be noted that by isolating and testing the main components to obtain their operating voltages, the relationship between the obtained operating voltages and temperature can reflect the influence of temperature on parameter drift, thus achieving temperature correction. Before temperature correction, a temperature correction model needs to be determined. For a single main component, the component parameters generally change linearly with temperature, so a linear model is usually directly adopted. However, in practice, to more closely reflect parameter changes, the collected data can be segmented, and then linear fitting can be performed on each segment.

[0098] Specifically, in step S401, the sequence data of the operating voltage of any major component at all independent temperatures during the isolation test is segmented to obtain several voltage change rate data segments.

[0099] In a specific embodiment of the present invention, the method for segmenting the sequence data of the operating voltages of any major component at all independent temperatures during isolation testing includes the following:

[0100] First, for any major component, the operating voltage of the major component at all independent temperatures is sorted in descending order of the corresponding independent temperatures, and the resulting sequence data is recorded as the operating voltage sequence of the major component. The operating voltage sequence is then fitted using the least squares method, and the rate of change of the operating voltage at each independent temperature is obtained from the curve fitting result. The sequence formed by the rate of change of the operating voltage at all independent temperatures is recorded as the voltage change rate sequence of the major component.

[0101] Then, mean-shift clustering is used to cluster all elements in the voltage change rate sequence to obtain several clusters. The data segments formed by the elements contained in the clusters in the voltage change rate sequence are denoted as voltage change rate data segments, thus obtaining several voltage change rate data segments.

[0102] Specifically, for elements that are less than or equal to Clusters are those containing elements less than or equal to The cluster is denoted as the first cluster. The cluster closest to the center of the first cluster and containing more than [a certain number of elements] is selected. The clusters are denoted as the target clusters of the first cluster, and the first clusters are merged into the corresponding target clusters. This is a preset quantity parameter.

[0103] It should be noted that the quantity parameters are preset based on experience. The value is 3, which can be adjusted according to the actual situation. This embodiment of the invention does not impose specific limitations.

[0104] Step S402: Perform data fitting on the voltage change rate data segment of any major component to determine the corresponding temperature correction model for the major component.

[0105] As a preferred embodiment, the method for obtaining the temperature correction model is as follows:

[0106] First, the least squares method and a univariate linear regression model are used to fit a straight line to any voltage change rate data segment of any major component.

[0107] Then, the root mean square error between the univariate linear regression model and the voltage change rate data segment during the linear fitting process of any voltage change rate data segment is obtained, denoted as the root mean square error of the fitting of the corresponding voltage change rate data segment. The slope and intercept of the linear fitting result of the corresponding voltage change rate data segment are obtained, denoted as the fitting slope and fitting result of the corresponding voltage change rate data segment. Combining the root mean square error, fitting slope and fitting intercept of all voltage change rate data segments of the main components, the linear model parameters of the main components are obtained. The linear model parameters include the slope coefficient and the intercept coefficient.

[0108] As an optional embodiment, for any major component, the specific calculation method for the linear model parameters of the major component is as follows:

[0109] ;

[0110] In the formula, The slope coefficients represent the linear model parameters of the main components; The intercept coefficients represent the linear model parameters of the main components; Indicates the first of the main components The root mean square error of fitting a voltage change rate data segment; Indicates the first of the main components The fitted slope of each voltage change rate data segment; Indicates the first of the main components The fitting intercept of each voltage change rate data segment; This indicates the number of data segments representing the voltage change rate of the main components.

[0111] Finally, using the linear model parameters of the main components and their independent temperatures, a temperature-voltage correction model for the main components is established, and this model is also used as the temperature-voltage correction model for all components in the component cluster.

[0112] As an optional embodiment, the specific formula for the temperature-voltage correction model of the main components is as follows:

[0113] ;

[0114] In the formula, Indicates the correction voltage for the main components; The slope coefficients represent the linear model parameters of the main components; The intercept coefficients represent the linear model parameters of the main components; This indicates the independent temperature of the main components.

[0115] It should be noted that since the main components are selected by the method in step S002 above and are used to represent all components in their respective component clusters, the temperature-voltage correction model of the main components obtained in this embodiment is also the temperature-voltage correction model of other components in the component cluster to which the main components belong.

[0116] Thus, the temperature-voltage correction model for each major component in the circuit board is obtained using the above method.

[0117] Step S005: Test the circuit board parameters using the temperature-voltage correction model of the components in the circuit board.

[0118] Specifically, firstly, the operating voltage of any component at several independent temperatures is obtained and denoted as the test voltage of the component.

[0119] Then, the independent temperature is used as the input to the temperature-voltage correction model of the component, and the correction voltage of the component is output by the temperature-voltage correction model.

[0120] Finally, the absolute value of the difference between the test voltage and the corresponding correction voltage of the component is recorded as the voltage deviation value of the component. When the voltage deviation value is greater than or equal to the preset voltage deviation threshold, the corresponding component is identified as an abnormal component.

[0121] It should be noted that, in this embodiment of the invention, the preset voltage deviation threshold is 0.5V based on experience, which can be adjusted according to the actual situation. This embodiment of the invention does not impose any specific limitations.

[0122] Based on the above steps, all components in the circuit board are tested. If an abnormal component is found in the circuit board, an early warning is issued directly, indicating that the corresponding circuit board is an abnormal circuit board.

[0123] By following the steps above, the parameter testing of the circuit board is completed.

[0124] Please see Figure 2 In another embodiment of the present invention, an automated circuit board parameter testing system is also provided, including a memory 202, a processor 201, and a computer program 2021 stored in the memory 202 and executable on the processor. When the processor 201 executes the computer program 2021, it implements steps S001 to S005 of the automated circuit board parameter testing method.

[0125] Furthermore, in an optional embodiment, the memory 202 described above may include read-only memory and random access memory, and provide instructions and data to the processor. The memory 202 may also include non-volatile random access memory. For example, the memory may also store device type information.

[0126] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for automated testing of circuit board parameters, characterized by, The method comprises the following steps: The test device is installed on the circuit board, and the test device comprises a high-low temperature box, a micro heating sheet, a thermocouple, an infrared imager, and a temperature controller; The set temperature of the high-low temperature box is iteratively increased, and a load is applied to the circuit board, and based on the difference between the corresponding temperatures of the components in the circuit board after the load is applied, a plurality of main components are screened out; Any main component is heated separately by the micro heating sheet with temperature iteration, a plurality of independent temperatures of the main component are obtained, and the working voltage of the main component at each independent temperature is obtained respectively; Based on the change of the working voltage of the main component at all independent temperatures, a plurality of voltage change rate data segments are obtained, and a temperature-voltage correction model of each component in the circuit board is established by combining the linear fitting of each voltage change rate data segment; The temperature-voltage correction model of the components in the circuit board is used for circuit board parameter testing; The construction method of the temperature-voltage correction model is: a linear fitting of any voltage change rate data segment of any main component is performed by using a least square method and a one-dimensional linear regression model; the root mean square error between the one-dimensional linear regression model corresponding to the linear fitting of any voltage change rate data segment and the voltage change rate data segment is obtained, which is recorded as the fitting root mean square error of the corresponding voltage change rate data segment, and the slope and intercept corresponding to the linear fitting result of the corresponding voltage change rate data segment are obtained, which are recorded as the fitting slope and fitting intercept of the corresponding voltage change rate data segment; the linear model parameters of the main component are obtained by combining the fitting root mean square error, fitting slope and fitting intercept of all voltage change rate data segments of the main component, and the linear model parameters include slope coefficient and intercept coefficient; the temperature-voltage correction model of the main component is established by using the linear model parameters of the main component and combining the independent temperature of the main component, and the temperature-voltage correction model of the main component is also used as the temperature-voltage correction model of all components in the corresponding component cluster.

2. The method of claim 1, wherein The set temperature of the high-low temperature box is iteratively increased, and a load is applied to the circuit board, and based on the difference between the corresponding temperatures of the components in the circuit board after the load is applied, a plurality of main components are screened out, which comprises the following specific method: The initial temperature of the high-low temperature box is preset, and the initial temperature is iteratively increased to obtain a plurality of test temperature conditions, and the temperatures of each component in the circuit board under different test temperature conditions are obtained by using the infrared imager; the relative temperature of the component is obtained according to the difference between the corresponding temperatures of different components under any test temperature condition; A plurality of main components are screened out from all components according to the similarity between the relative temperatures of different components under all test temperature conditions.

3. The method of claim 2, wherein The specific method for obtaining the relative temperature is: The initial temperature of the high-low temperature box is preset, and the temperature set for the high-low temperature box is used as the test temperature condition; the circuit board is placed in the high-low temperature box, and a load is provided for the circuit board to simulate the actual work of the circuit board; An infrared imager located directly above the circuit board is used to obtain an infrared image of the circuit board, and a YOLO algorithm is used to identify a plurality of components in the infrared image of the circuit board and obtain the temperatures of all the components. Any component is taken as a target component, the absolute value of the temperature difference between the target component and each of the other components is taken as the temperature deviation between the target component and the other component, the average of the temperature deviations between the target component and all the other components is taken as the relative temperature of the target component. The temperature in the high-low temperature chamber is gradually increased by a preset step b to obtain a plurality of test temperature conditions, and the relative temperature of the target component in the circuit board under each test temperature condition is obtained.

4. The method of claim 2, wherein The specific method for screening a plurality of main components from all the components according to the similarity between the relative temperatures of different components under all test temperature conditions comprises the following steps: The relative temperatures of any component under all test temperature conditions are obtained, and the relative temperatures of the component under all test temperature conditions are sorted in ascending order according to the corresponding values of the test temperature conditions to obtain the relative temperature sequence of the component. The cosine similarity between the relative temperature sequences of any two components is taken as the distance measurement method of the mean shift clustering algorithm, so that all the components on the circuit board are subjected to clustering processing to obtain a plurality of component clusters. In any component cluster, the component closest to the cluster center of the component cluster is taken as a main component.

5. The method of claim 1, wherein The specific method for individually heating any main component by a micro-heating sheet with iteratively increased temperature comprises the following steps: For any main component, a micro-heating sheet is pasted on the surface of the main component with thermal conductive glue, and the lead wire of the micro-heating sheet is connected to a temperature controller. Then, a thermocouple is pasted on the other end of the main component with thermal conductive glue, so that the thermocouple is symmetrically positioned with the micro-heating sheet. The temperature of the main component is measured by the thermocouple during heating of the main component by the micro-heating sheet. The test temperature condition is controlled by the high-low temperature chamber to be a preset initial temperature, and the temperature of the main component is collected by the thermocouple during heating of the main component by the micro-heating sheet. The temperature of the main component collected by the thermocouple is recorded as the independent temperature of the main component. When the absolute value of the difference between the independent temperature of the main component and the initial temperature is less than or equal to a preset difference threshold, the operating voltage of the main component at the corresponding independent temperature is obtained. During the heating of the temperature of the main component by the micro-heating sheet, the temperature growth step of the micro-heating sheet is calculated according to the voltage change of the main component, and the heating temperature of the micro-heating sheet is iteratively increased by the temperature growth step, so that the operating voltage of the main component at a plurality of independent temperatures is obtained.

6. The method of claim 5, wherein, The specific method for obtaining the temperature growth step comprises the following steps: A preset temperature step factor is set, when heating any main component by the micro-heating sheet, the independent temperature of the main component is obtained, when the value of the independent temperature of the main component rises to the value of the temperature compensation factor, the parameter variation coefficient of the main component is calculated according to the voltage variation of the main component; The independent temperature corresponding to each time when the parameter variation coefficient of the main component is greater than or equal to the preset parameter variation threshold value is obtained as the corresponding conditional independent temperature, and the difference between the current conditional independent temperature of the main component and the last conditional independent temperature is taken as the temperature growth step.

7. The method of claim 1, wherein The specific method based on the voltage variation of the main component at all independent temperatures includes: For any main component, the working voltage of the main component at all independent temperatures is sorted in descending order of the corresponding independent temperature, and the formed sequence data is recorded as the working voltage sequence of the main component, the least square method is used to curve fit the working voltage sequence, and the change rate of the working voltage at each independent temperature in the curve fitting result is obtained, and the sequence formed by the change rate of the working voltage at all independent temperatures is recorded as the voltage change rate sequence of the main component; All elements in the voltage change rate sequence are clustered by using the mean shift clustering to obtain a plurality of clustering clusters, and the data segment formed by the elements contained in the clustering cluster in the voltage change rate sequence is recorded as the voltage change rate data segment, and a plurality of voltage change rate data segments are obtained.

8. The method of claim 1, wherein The specific method for testing the circuit board parameters by using the temperature-voltage correction model of the components in the circuit board includes: The working voltage of any component at the independent temperature is obtained at a plurality of independent temperatures, which is recorded as the test voltage of the component; The independent temperature is taken as the input of the temperature-voltage correction model of the component, and the corrected voltage of the component is output by the temperature-voltage correction model; The absolute value of the difference between the test voltage of the component and the corresponding corrected voltage is recorded as the voltage deviation value of the component, and when the voltage deviation value is greater than or equal to the preset voltage deviation threshold value, the corresponding component is determined as an abnormal component.

9. An automated circuit board parameter testing system comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein, The processor executes the computer program to realize the steps of the circuit board parameter automatic test method according to any one of claims 1-8.

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