A method and system for detecting high impedance performance of a PCB board

Abstract

The present application relates to the technical field of PCB board, especially relates to a kind of performance detection method and system of PCB board high impedance.It is obtained according to the temperature compensation of the actual resistance value of the preset measurement point of resistance temperature coefficient to multiple correction resistance values, can eliminate the error caused by temperature fluctuation, so that measurement result is more accurate and consistent, by compensating temperature variation, subsequent more accurately measured and evaluated the actual high impedance performance of PCB can be facilitated, to improve the precision of overall measurement, by real-time acquisition signal waveform diagram can realize effective observation high impedance area actual response under load, provide dynamic information about circuit performance, can identify the influence of load on circuit, by applying load and analyzing waveform diagram, can evaluate performance under actual use condition, optimize the relevance of detection result, in combination with resistance distribution and real-time signal analysis, can more comprehensively understand the high impedance characteristics of circuit, to improve measurement accuracy and reliability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of PCB board, in particular to a performance detection method and system for high impedance of PCB board. BACKGROUND

[0002] In recent years, with the rapid development of electronic products such as desktop computers (control terminals), notebook computers, mobile phones, digital televisions, set-top boxes, consumer electronics (MP3, MP4, game consoles, digital cameras, etc.), communication equipment and automobile electronics, the signal transmission frequency and speed are getting faster and faster, and strict characteristic impedance test requirements are put forward for the used circuit board (PCB board). In the detection types of PCB board, the PCB impedance detection is to check whether the impedance of the PCB meets the design requirements. As the signal frequency on the PCB is getting higher and higher, the noise and waveform distortion on the signal have become the main factors affecting the signal integrity. If the impedance of the PCB does not meet the requirements, it will cause signal reflection and signal loss, thereby affecting the signal integrity. Therefore, the PCB impedance test is an important step to ensure the electrical performance of the PCB. In order to control the line impedance, it is necessary to strictly test the characteristic impedance of each generated PCB board to check whether it meets the design and generation requirements.

[0003] At present, the performance of high impedance of PCB board is mainly detected by voltage drop method. Specifically, a high-precision voltmeter and a current source are used to identify the test points or lines on the PCB first, then a stable current source is connected to the input end of the circuit, the two probes of the voltmeter are connected to the two ends of the test points respectively, a known current is applied to the circuit by the current source, and then the voltage drop between the test points when the current is applied is measured by using the voltmeter and the resistance value is calculated. The measured resistance value is compared with the design specification or expected value to evaluate the performance of the circuit. However, in the case of high impedance, the current is very small, and the voltage drop may be very weak. In the high impedance circuit, small noise signals may be amplified, thereby affecting the measurement result of the voltage drop method, and further leading to low measurement accuracy. SUMMARY

[0004] The main purpose of the present application is to provide a performance detection method and system for high impedance of PCB board, which aims to solve the technical problems in the prior art.

[0005] The present application provides a performance detection method for high impedance of PCB board, comprising:

[0006] obtaining an image of the PCB board, and obtaining a plurality of preset measurement points according to the image;

[0007] obtaining an actual resistance value and an actual temperature value of each preset measurement point, wherein the plurality of preset measurement points are arrayed;

[0008] The resistance temperature coefficient of each preset measurement point is calculated according to each actual resistance value and a corresponding actual temperature value, and the actual resistance value of each preset measurement point is temperature-compensated according to the resistance temperature coefficient, so as to obtain a plurality of corrected resistance values;

[0009] The plurality of corrected resistance values are plotted into a resistance distribution graph, and a high-impedance region is obtained according to the resistance distribution graph;

[0010] A preset load application table is obtained, and a load is applied to the high-impedance region according to the preset load application table, wherein the preset load application table comprises a plurality of load values arranged in order of size;

[0011] A total signal waveform graph of the high-impedance region when the load is applied is obtained in real time, and a performance evaluation value is obtained according to the total signal waveform graph;

[0012] It is judged whether the performance evaluation value is located in a preset performance evaluation value interval;

[0013] If the performance evaluation value is located in the preset performance evaluation value interval, it is determined that the high-impedance performance of the PCB board is good;

[0014] If the performance evaluation value is not located in the preset performance evaluation value interval, it is determined that the high-impedance performance of the PCB board is poor.

[0015] Preferably, the step of calculating the resistance temperature coefficient of each preset measurement point according to each actual resistance value and a corresponding actual temperature value comprises:

[0016] A plurality of historical temperature values of the PCB board are obtained;

[0017] A corresponding historical resistance value of each preset measurement point is obtained according to each historical temperature value;

[0018] The resistance temperature coefficient is calculated according to the actual resistance value, the actual temperature value, the plurality of historical temperature values and the historical resistance value, wherein the calculation formula is:

[0019] ;

[0020] Wherein, W(X) represents the resistance temperature coefficient, S(D) represents the actual resistance value, Y(D) i represents the i-th historical resistance value, S(W) represents the actual temperature value, Y(W) i represents the i-th historical temperature value, i represents the serial number of the historical resistance value, and n represents the number of historical resistance values.

[0021] Preferably, the step of temperature-compensating the actual resistance value of each preset measurement point according to the resistance temperature coefficient to obtain a plurality of corrected resistance values comprises:

[0022] obtaining a resistance temperature coefficient and an actual temperature value;

[0023] obtaining a reference temperature value of the PCB, and obtaining a temperature compensation value according to the reference temperature value, the resistance temperature coefficient, the actual temperature value and the actual resistance value;

[0024] judging whether the temperature compensation value is positive;

[0025] if the temperature compensation value is positive, obtaining a corrected resistance value according to a difference between the actual temperature value and the temperature compensation value;

[0026] if the temperature compensation value is negative, obtaining a corrected resistance value according to a sum between the actual temperature value and the temperature compensation value.

[0027] As a preferred, the step of drawing multiple corrected resistance values into a resistance distribution graph, and obtaining a high impedance area according to the resistance distribution graph, comprises:

[0028] obtaining a corresponding temperature value according to each corrected resistance value;

[0029] establishing a resistance distribution coordinate axis with the temperature value as the X axis and the corrected resistance value as the Y axis, and drawing each corrected resistance value and the corresponding temperature value on the resistance distribution coordinate axis through a curve to obtain a resistance distribution graph;

[0030] obtaining a preset corrected resistance value, and drawing a division line on the resistance distribution graph according to the preset corrected resistance value;

[0031] obtaining first position information of each corrected resistance value above the division line in the image and second position information of each corrected resistance value below the division line in the image;

[0032] marking multiple first position information as white in the image, and connecting multiple first position information marked as white through horizontal lines and vertical lines to obtain a first area;

[0033] marking multiple second position information as black in the image, and connecting multiple second position information marked as black through horizontal lines and vertical lines to obtain a second area;

[0034] eliminating an area where the first area and the second area overlap in the first area to obtain a high impedance area.

[0035] As a preferred, the step of obtaining a total signal waveform graph of the high impedance area when a load is applied in real time, comprises:

[0036] obtaining a load waveform graph of the high impedance area within a preset time under each load value;

[0037] acquiring a plurality of peak values and valley values of each of the load waveform diagrams;

[0038] acquiring a corresponding falling time point according to each of the peak values and a corresponding rising time point according to the valley values;

[0039] drawing a total signal waveform diagram according to the plurality of peak values, the corresponding falling time points, the valley values and the corresponding rising time points.

[0040] As a preferred, the step of acquiring the performance evaluation value according to the total signal waveform diagram comprises:

[0041] acquiring a highest peak value and a lowest valley value of the total signal waveform diagram, and calculating a signal amplitude attenuation percentage according to the highest peak value and the lowest valley value, wherein the calculation formula is:

[0042] ;

[0043] wherein F(S) represents the signal amplitude attenuation percentage, Z(G) represents the highest peak value, and Z(D) represents the lowest valley value;

[0044] acquiring an ideal phase value;

[0045] acquiring an actual phase value according to the total signal waveform diagram, and obtaining a phase distortion degree according to a difference between the actual phase value and the ideal phase value;

[0046] acquiring a noise amplitude at each time point according to the total signal waveform diagram, and calculating a noise level degree value according to a plurality of the noise amplitudes, wherein the calculation formula is:

[0047] ;

[0048] wherein Z(S) represents the noise level degree value, Z(F) m represents the mth noise amplitude, M represents the number of the noise amplitudes, and m represents the serial number of the noise amplitude;

[0049] acquiring a first weight of the signal amplitude attenuation percentage, a second weight of the phase distortion degree, and a third weight of the noise level degree value;

[0050] calculating the performance evaluation value according to the noise level degree value, the phase distortion degree, the signal amplitude attenuation percentage, the first weight, the second weight and the third weight, wherein the calculation formula is:

[0051] ;

[0052] Wherein, X(P) represents a performance evaluation value, Z(S) represents a noise level degree value, F(S) represents a signal amplitude attenuation percentage, X(S) represents a phase distortion degree, a represents a first weight, b represents a second weight, and c represents a third weight.

[0053] The application also provides a high-impedance performance detection system for a PCB, comprising:

[0054] A first obtaining module is configured to obtain an image of the PCB and a plurality of preset measurement points according to the image;

[0055] A second obtaining module is configured to obtain an actual resistance value and an actual temperature value of each preset measurement point, wherein the plurality of preset measurement points are arranged in an array.

[0056] A calculating module is configured to calculate a resistance temperature coefficient of each preset measurement point according to each actual resistance value and corresponding actual temperature value, and to perform temperature compensation on the actual resistance value of each preset measurement point according to the resistance temperature coefficient to obtain a plurality of corrected resistance values.

[0057] A drawing module is configured to draw the plurality of corrected resistance values into a resistance distribution map and to obtain a high-impedance region according to the resistance distribution map.

[0058] An applying module is configured to obtain a preset load application table and to apply a load to the high-impedance region according to the preset load application table, wherein the preset load application table comprises a plurality of load values arranged in order of size.

[0059] A third obtaining module is configured to obtain a total signal waveform map of the high-impedance region when the load is applied in real time and to obtain a performance evaluation value according to the total signal waveform map.

[0060] A judging module is configured to judge whether the performance evaluation value is within a preset performance evaluation value interval.

[0061] If the performance evaluation value is within the preset performance evaluation value interval, it is determined that the high-impedance performance of the PCB is good.

[0062] If the performance evaluation value is not within the preset performance evaluation value interval, it is determined that the high-impedance performance of the PCB is poor.

[0063] Preferably, the drawing module comprises:

[0064] A first obtaining unit is configured to obtain a corresponding temperature value according to each corrected resistance value.

[0065] A drawing unit is configured to establish a resistance distribution coordinate axis with a temperature value as an X-axis and a corrected resistance value as a Y-axis, to draw each corrected resistance value and corresponding temperature value on the resistance distribution coordinate axis through a curve, and to obtain a resistance distribution map.

[0066] The second acquisition unit is configured to acquire a preset correction resistance value and draw a division line on a resistance distribution map according to the preset correction resistance value.

[0067] The third acquisition unit is configured to acquire first position information of each correction resistance value above the division line in the image and second position information of each correction resistance value below the division line in the image.

[0068] The first marking unit is configured to mark a plurality of the first position information as white in the image, and connect the plurality of the first position information marked as white through horizontal lines and vertical lines to obtain a first region.

[0069] The second marking unit is configured to mark a plurality of the second position information as black in the image, and connect the plurality of the second position information marked as black through horizontal lines and vertical lines to obtain a second region.

[0070] The elimination unit is configured to eliminate an area in which the first region and the second region overlap in the first region to obtain a high-impedance region.

[0071] The application further provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the PCB high-impedance performance detection method when executing the computer program.

[0072] The application further provides a computer readable storage medium, which stores a computer program, and the computer program implements the steps of the PCB high-impedance performance detection method when executed by a processor.

[0073] The beneficial effects of the present application are: the present application calculates the resistance temperature coefficient of the preset measurement point according to the actual resistance value and the corresponding actual temperature value, and carries out temperature compensation on the actual resistance value of the preset measurement point according to the resistance temperature coefficient to obtain a plurality of corrected resistance values, which can eliminate errors caused by temperature fluctuations, make the measurement result more accurate and consistent, and through compensating the temperature change, the actual high impedance performance of the PCB can be more accurately measured and evaluated subsequently, thereby improving the overall measurement accuracy, by drawing the plurality of corrected resistance values into a resistance distribution graph, obtaining a high impedance region according to the resistance distribution graph, then applying a load to the high impedance region through a preset load application table, then obtaining a total signal waveform graph of the high impedance region when the load is applied in real time, and obtaining a performance evaluation value according to the total signal waveform graph, through real-time acquisition of the signal waveform graph, the actual response of the high impedance region under the load can be effectively observed, dynamic information about the circuit performance is provided, the influence of the load on the circuit can be identified, through applying the load and analyzing the waveform graph, the performance under actual use conditions can be evaluated, the relevance of the detection result is optimized, and in combination with the resistance distribution graph and real-time signal analysis, the high impedance characteristics of the circuit can be more comprehensively understood, thereby improving the measurement accuracy and reliability. BRIEF DESCRIPTION OF DRAWINGS

[0074] Fig. 1 The method flowchart of an embodiment of the present application.

[0075] Fig. 2 The device structure schematic diagram of an embodiment of the present application.

[0076] Fig. 3 The internal structure schematic diagram of a computer device of an embodiment of the present application.

[0077] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0078] It should be understood that the specific embodiments described herein are merely intended to explain the present application, and are not intended to limit the present application.

[0079] As shown in the drawings, the present application provides a performance detection method for high impedance of a PCB, comprising: Figs. 1-3

[0080] S1, obtaining an image of the PCB, and obtaining a plurality of preset measurement points according to the image;

[0081] S2, obtaining an actual resistance value and an actual temperature value of each preset measurement point, wherein the plurality of preset measurement points are arrayed;

[0082] ​S3, calculating a resistance temperature coefficient of each preset measurement point according to each actual resistance value and a corresponding actual temperature value, and performing temperature compensation on the actual resistance value of each preset measurement point according to the resistance temperature coefficient to obtain a plurality of corrected resistance values;

[0083] S4, drawing a resistance distribution map according to the plurality of corrected resistance values, and obtaining a high impedance region according to the resistance distribution map;

[0084] S5, obtaining a preset load application table, and applying a load to the high impedance region according to the preset load application table, wherein the preset load application table comprises a plurality of load values arranged in order of size;

[0085] S6, obtaining a total signal waveform graph of the high impedance region when the load is applied in real time, and obtaining a performance evaluation value according to the total signal waveform graph;

[0086] S7, judging whether the performance evaluation value is located in a preset performance evaluation value interval;

[0087] If the performance evaluation value is located in the preset performance evaluation value interval, it is determined that the high impedance performance of the PCB board is good;

[0088] If the performance evaluation value is not located in the preset performance evaluation value interval, it is determined that the high impedance performance of the PCB board is poor.

[0089] As described in steps S1-S7 above, in recent years, with the rapid development of electronic products such as desktop computers, notebook computers, mobile phones, digital televisions, set-top boxes, consumer electronics, communication equipment and automotive electronics, the signal transmission frequency and speed are getting faster and faster, and strict characteristic impedance test requirements are put forward for the PCB used. Among the detection types of the PCB, the PCB impedance detection is to check whether the impedance of the PCB meets the design requirements. At present, the impedance of the PCB is mainly detected by the voltage drop method to detect the high impedance performance of the PCB. Specifically, a high-precision voltmeter and a current source are used to identify the test points or lines on the PCB first, then a stable current source is connected to the input end of the circuit, the two probes of the voltmeter are connected to the two ends of the test points respectively, a known current is applied to the circuit by the current source, and then the voltage drop between the test points when the current is applied is measured by using the voltmeter and the resistance value is calculated. The measured resistance value is compared with the design specification or expected value to evaluate the performance of the circuit. However, in the case of high impedance, the measurement accuracy may be limited by the current source and the voltmeter, thereby affecting the test results.In the present application, by obtaining the actual resistance values and actual temperature values of multiple preset measurement points on the PCB image, then calculating the resistance temperature coefficient of each preset measurement point according to each actual resistance value and the corresponding actual temperature value, and performing temperature compensation on the actual resistance value of each preset measurement point according to the resistance temperature coefficient, multiple corrected resistance values are obtained, wherein the array distribution of the multiple preset measurement points means that these preset measurement points are arranged in a grid-shaped array according to certain rules or patterns (such as equidistant horizontal or vertical distribution), because random or uneven distribution of measurement points will lead to inaccurate positioning of high impedance areas, especially in areas with dramatic resistance changes, which may ignore the detection of other areas, resulting in incomplete detection results. Since resistance values usually change with temperature, by calculating the resistance temperature coefficient and performing temperature compensation on the actual resistance value, errors caused by temperature fluctuations can be eliminated, making the measurement results more accurate and consistent. In high impedance areas, small resistance changes can have a significant impact on performance, and by compensating for temperature changes, subsequent more accurate measurement and evaluation of the actual high impedance performance of the PCB can be facilitated, thereby improving the overall measurement accuracy. Compensation under different temperature conditions can ensure the consistency of test results, making test data comparable under different environmental conditions and improving the reliability of test results. By plotting the multiple corrected resistance values into a resistance distribution map, obtaining the high impedance area according to the resistance distribution map, applying a load to the high impedance area through a preset load application table, then obtaining the total signal waveform graph of the high impedance area when the load is applied in real time, and obtaining the performance evaluation value according to the total signal waveform graph, the resistance distribution map can effectively identify the high impedance area, ensuring that the test and load application are concentrated in the key area, thereby more accurately evaluating the performance of these areas. By obtaining the signal waveform graph in real time, the actual response of the high impedance area under load can be effectively observed, providing dynamic information about the performance of the circuit, and the impact of the load on the circuit can be identified. By applying a load and analyzing the waveform graph, the performance under actual use conditions can be evaluated, making the test more close to the actual working environment, optimizing the relevance of the detection results. Combined with the resistance distribution map and real-time signal analysis, a more comprehensive understanding of the high impedance characteristics of the circuit can be obtained, thereby improving the measurement accuracy and reliability. By summarizing the signal waveforms under different load conditions, a comprehensive understanding of the behavior of the high impedance area under various load conditions can be obtained, which helps to identify the impact of load changes on the high impedance area, thereby providing a more accurate evaluation of the performance under actual working conditions. Moreover, a more comprehensive view of the performance of the high impedance area can also be provided, which can more accurately reflect the performance in the actual use environment, improving the reliability and accuracy of performance evaluation. Then, by judging whether the performance evaluation value is within the preset performance evaluation value interval, if the performance evaluation value is within the preset performance evaluation value interval, it is determined that the high impedance performance of the PCB is good, otherwise it is determined that the high impedance performance of the PCB is poor.

[0090] In one embodiment, the step S3 of calculating the resistance temperature coefficient of each preset measurement point according to each actual resistance value and corresponding actual temperature value comprises:

[0091] S31, obtaining a plurality of historical temperature values of the PCB board;

[0092] S32, obtaining a corresponding historical resistance value of each preset measurement point according to each historical temperature value;

[0093] S33, calculating the resistance temperature coefficient according to the actual resistance value, the actual temperature value, the plurality of historical temperature values and the historical resistance value, wherein the calculation formula is:

[0094]

[0095] wherein W(X) represents the resistance temperature coefficient, S(D) represents the actual resistance value, Y(D) i represents the i-th historical resistance value, S(W) represents the actual temperature value, Y(W) i represents the i-th historical temperature value, i represents the serial number of the historical resistance value, and n represents the number of historical resistance values.

[0096] As described in steps S31-S33, the application obtains a plurality of historical temperature values of the PCB board and a corresponding historical resistance value of each preset measurement point, and then calculates the resistance temperature coefficient according to the actual resistance value, the actual temperature value, the plurality of historical temperature values and the historical resistance value. The calculation of the resistance temperature coefficient can more accurately compensate for the influence of temperature on the resistance value, thereby reducing the interference of temperature change on high-impedance measurement, improving the measurement accuracy, and more comprehensively evaluating the performance of the high-impedance region in the actual working environment by considering the resistance change at different temperatures, thereby ensuring the accuracy and reliability of the test data.

[0097] In one embodiment, the step S3 of calculating the resistance temperature coefficient of each preset measurement point according to each actual resistance value and corresponding actual temperature value comprises:

[0098] S34, obtaining the resistance temperature coefficient and the actual temperature value;

[0099] S35, obtaining a reference temperature value of the PCB board;

[0100] S36, calculating a temperature compensation value according to the reference temperature value, the resistance temperature coefficient, the actual temperature value and the actual resistance value, wherein the calculation formula is:

[0101]

[0102] ​​Wherein, W(B) represents a temperature compensation value, S(D) represents an actual resistance value, W(X) represents a resistance temperature coefficient, S(W) represents an actual temperature value, and J(W) represents a reference temperature value;

[0103] S37, judging whether the temperature compensation value is positive;

[0104] If the temperature compensation value is positive, a corrected resistance value is obtained according to a difference between the actual temperature value and the temperature compensation value;

[0105] If the temperature compensation value is negative, a corrected resistance value is obtained according to a sum of the actual temperature value and the temperature compensation value.

[0106] As described in steps S34-S37, the application obtains the resistance temperature coefficient, the actual temperature value, and the reference temperature value of the PCB, and then calculates the temperature compensation value according to the reference temperature value, the resistance temperature coefficient, the actual temperature value, and the actual resistance value. Then, it judges whether the temperature compensation value is positive. If it is positive, a corrected resistance value is obtained according to a difference between the actual temperature value and the temperature compensation value. If it is not positive, a corrected resistance value is obtained according to a sum of the actual temperature value and the temperature compensation value. The temperature compensation value calculated by using the resistance temperature coefficient, the actual temperature value, and the reference temperature value can accurately adjust the resistance value and eliminate the resistance value deviation caused by temperature changes. This ensures that the measured value is closer to the true value, thereby improving the measurement accuracy of high impedance performance. By compensating for the resistance value change caused by temperature changes, the measurement error caused by temperature fluctuations can be greatly reduced, making the test results more consistent and reliable under different environmental temperatures. Through temperature compensation processing, consistent measurement results can be obtained under different temperature conditions, thereby improving the repeatability and consistency of the test.

[0107] In one embodiment, the step S4 of drawing a plurality of the corrected resistance values into a resistance distribution map and obtaining a high impedance region according to the resistance distribution map comprises:

[0108] S41, obtaining a corresponding temperature value according to each of the corrected resistance values;

[0109] S42, establishing a resistance distribution coordinate axis with the temperature value as the X-axis and the corrected resistance value as the Y-axis, and drawing each corrected resistance value and the corresponding temperature value on the resistance distribution coordinate axis through a curve to obtain a resistance distribution map;

[0110] S43, obtaining a preset corrected resistance value and drawing a division line on the resistance distribution map according to the preset corrected resistance value;

[0111] S44, obtaining first position information of each corrected resistance value above the division line in the image and second position information of each corrected resistance value below the division line in the image.

[0112] S45, marking the first position information as white in the image, and connecting the first position information marked as white through horizontal lines and vertical lines to obtain a first region;

[0113] S46, marking the second position information as black in the image, and connecting the second position information marked as black through horizontal lines and vertical lines to obtain a second region;

[0114] S47, removing the region of the first region overlapping with the second region in the first region to obtain a high-impedance region.

[0115] In the test of the PCB board, as described in steps S41-S47, high impedance generally refers to that some paths, signal lines or areas on the circuit board have very high resistance values. If the entire PCB board is directly measured, not only a large amount of data will be generated, resulting in low efficiency and reduced accuracy, but also the high impedance area is not easy to identify from the interference of other area signals, thereby leading to inaccurate detection results. Therefore, the application obtains the corresponding temperature value according to each corrected resistance value, establishes a resistance distribution coordinate axis with the temperature value as the X-axis and the corrected resistance value as the Y-axis, and draws each corrected resistance value and the corresponding temperature value on the resistance distribution coordinate axis through a curve to obtain a resistance distribution graph. The resistance distribution graph can intuitively show the change trend of the resistance value at different temperatures, help identify the law of resistance change with temperature, and facilitate the analysis of the performance of the high impedance area. By observing the resistance distribution graph, the change of the resistance at different temperatures can be more accurately understood, thereby optimizing the temperature compensation strategy and improving the accuracy and reliability of the measurement. The distribution graph can help identify the nonlinear behavior or abnormal pattern of resistance change with temperature, discover potential design defects or material problems in time, and facilitate correction. By drawing a segmentation line on the resistance distribution graph through the preset corrected resistance value, then obtaining first position information of each corrected resistance value above the segmentation line in the image and second position information of each corrected resistance value below the segmentation line in the image, the segmentation line can help distinguish normal and abnormal resistance values, so that abnormal resistance values are easy to identify and locate, thereby improving the measurement accuracy. By comparing the resistance values above and below the segmentation line, the resistance performance of different areas can be more clearly evaluated, thereby optimizing the performance evaluation and determining which corrected resistance values are on both sides of the segmentation line, which can help adjust the temperature compensation strategy to make it more suitable for different resistance areas, improve the overall measurement accuracy, mark the multiple first position information as white in the image and connect them through horizontal and vertical lines to obtain a first area, mark the multiple second position information as black in the image and connect them through horizontal and vertical lines to obtain a second area, and finally remove the area overlapping the first area and the second area in the first area to obtain a high impedance area. By marking and connecting different areas, the position of the high impedance area on the PCB board can be accurately determined, so that optimization and maintenance of these areas are more efficient. Distinguishing the first area and the second area helps analyze the performance in different resistance ranges to ensure that the resistance characteristics of the high impedance area are consistent with the expectations, thereby improving the accuracy of data analysis. By identifying the high impedance area, the test can be focused on these key areas, improving the detection efficiency and reducing invalid detection.

[0116] In one embodiment, the step S6 of obtaining the total signal waveform graph of the high impedance area when the load is applied in real time comprises:

[0117] S61, obtaining a load waveform graph of the high impedance area within a preset time at each load value;

[0118] S62, obtaining a plurality of peak values and valley values of each of the load waveform graphs;

[0119] S63, obtaining a corresponding falling time point according to each of the peak values and a corresponding rising time point according to the valley values;

[0120] drawing a total signal waveform graph according to the plurality of peak values, the corresponding falling time points, the valley values and the corresponding rising time points.

[0121] As described in the above steps S61-S63, the present application obtains the load waveform graph of the high impedance region within a predetermined time at each load value, obtains a plurality of peak values and corresponding falling time points and valley values and corresponding rising time points of each of the load waveform graphs, and then draws a total signal waveform graph according to the plurality of peak values, the corresponding falling time points, the valley values and the corresponding rising time points. This can more comprehensively analyze the signal characteristics of the high impedance region, including peak values, valley values and response times, provide more detailed performance evaluation, and by comparing the waveform graphs under different load conditions, potential problems of the high impedance region such as inconsistent response or abnormal fluctuations can be identified, thereby targeted adjustment and optimization can be performed, the signal waveform characteristics under various load conditions are understood, which helps to optimize the design and temperature compensation strategy, and considering the signal waveform under different load conditions helps to improve the measurement accuracy of the performance of the high impedance region, reduce measurement errors caused by load changes, and the signal waveform graphs under different conditions can verify the reliability of the high impedance region under various working conditions, and ensure the robustness and consistency of the performance of the design.

[0122] In one embodiment, the step S6 of obtaining a performance evaluation value according to the total signal waveform graph comprises:

[0123] S64, obtaining the highest peak value and the lowest valley value of the total signal waveform graph, and calculating the signal amplitude decay percentage according to the highest peak value and the lowest valley value, wherein the calculation formula is:

[0124] ;

[0125] wherein F(S) represents the signal amplitude decay percentage, Z(G) represents the highest peak value, and Z(D) represents the lowest valley value;

[0126] S65, obtaining an ideal phase value;

[0127] S66, obtaining an actual phase value according to the total signal waveform graph, and obtaining a phase distortion degree according to the difference between the actual phase value and the ideal phase value;

[0128] S67, obtain the noise amplitude at each time point according to the total signal waveform diagram, and calculate the noise level degree value according to a plurality of the noise amplitudes, wherein the calculation formula is:

[0129] ;

[0130] Wherein, Z(S) represents the noise level degree value, Z(F) m represents the mth noise amplitude, M represents the number of noise amplitudes, and m represents the serial number of the noise amplitude;

[0131] S68, obtain the first weight of the signal amplitude attenuation percentage, obtain the second weight of the phase distortion degree, and obtain the third weight of the noise level degree value;

[0132] S69, calculate the performance evaluation value according to the noise level degree value, the phase distortion degree, the signal amplitude attenuation percentage, the first weight, the second weight and the third weight, wherein the calculation formula is:

[0133] ;

[0134] Wherein, X(P) represents the performance evaluation value, Z(S) represents the noise level degree value, F(S) represents the signal amplitude attenuation percentage, X(S) represents the phase distortion degree, a represents the first weight, b represents the second weight, and c represents the third weight.

[0135] As described in steps S64-S69 above, this invention obtains the highest peak and lowest trough values ​​of the total signal waveform and calculates the signal amplitude attenuation percentage based on these values. The signal amplitude attenuation percentage provides a measure of signal attenuation in the high-impedance region under different load conditions, making performance evaluation more quantitative and accurate. The calculation of amplitude attenuation helps identify and quantify performance degradation in the high-impedance region. Through amplitude attenuation analysis, the stability and reliability of the high-impedance region under different operating conditions can be verified. Calculating the amplitude attenuation percentage allows for a more accurate assessment of the actual performance of the high-impedance region, reducing measurement errors caused by signal fluctuations. By obtaining the ideal phase value, the actual phase value is obtained from the total signal waveform, and the phase distortion is calculated based on the difference between the actual and ideal phase values. The calculation of phase distortion quantifies the phase deviation of the signal during transmission in the high-impedance region of the PCB, thus providing an accurate assessment of signal integrity and transmission quality. The calculation of phase distortion helps to finely adjust the testing process and equipment settings, thereby improving measurement accuracy. This method reduces errors caused by phase distortion. It obtains the noise amplitude at each time point based on the overall signal waveform and calculates the noise level value based on multiple noise amplitudes. The noise level value provides a quantitative assessment of the impact of noise on the high-impedance region, allowing for an accurate understanding of the degree of noise interference with the signal. Calculating the noise level value improves the overall measurement accuracy. Performance evaluation values ​​are calculated based on the noise level value, phase distortion, signal amplitude attenuation percentage, first weight, second weight, and third weight. Combining multiple performance indicators such as noise level, phase distortion, and signal attenuation provides a comprehensive evaluation, offering a more accurate overall performance view of the high-impedance region. Using weights to assign weights to different performance indicators ensures that the evaluation value reflects the relative importance of each indicator to the overall performance, thus providing an objective performance evaluation standard. By integrating various indicators, the performance of the high-impedance region of the PCB can be evaluated more accurately, reducing errors that may be caused by a single indicator and improving overall measurement accuracy. This method makes performance evaluation more comprehensive and accurate.

[0136] This application also provides a performance testing system for high impedance of PCB boards, including:

[0137] The first acquisition module is used to acquire an image of the PCB board and acquire multiple preset measurement points based on the image;

[0138] The second acquisition module is used to acquire the actual resistance value and actual temperature value of each preset measurement point, wherein multiple preset measurement points are distributed in an array;

[0139] a calculating module, configured to calculate a resistance temperature coefficient of each preset measurement point according to each actual resistance value and a corresponding actual temperature value, and to perform temperature compensation on the actual resistance value of each preset measurement point according to the resistance temperature coefficient, to obtain a plurality of corrected resistance values;

[0140] a drawing module, configured to draw the plurality of corrected resistance values into a resistance distribution map, and to obtain a high-impedance region according to the resistance distribution map;

[0141] an applying module, configured to obtain a preset load application table, and to apply a load to the high-impedance region according to the preset load application table, wherein the preset load application table includes a plurality of load values arranged in order of size;

[0142] a third obtaining module, configured to obtain a total signal waveform diagram of the high-impedance region when the high-impedance region is applied with the load in real time, and to obtain a performance evaluation value according to the total signal waveform diagram;

[0143] a judging module, configured to judge whether the performance evaluation value is located within a preset performance evaluation value interval;

[0144] if the performance evaluation value is located within the preset performance evaluation value interval, it is determined that the high-impedance performance of the PCB board is good;

[0145] if the performance evaluation value is not located within the preset performance evaluation value interval, it is determined that the high-impedance performance of the PCB board is poor.

[0146] In one embodiment, the drawing module includes:

[0147] a first obtaining unit, configured to obtain a corresponding temperature value according to each corrected resistance value;

[0148] a drawing unit, configured to establish a resistance distribution coordinate axis with the temperature value as an X axis and the corrected resistance value as a Y axis, and to draw each corrected resistance value and the corresponding temperature value on the resistance distribution coordinate axis through a curve, to obtain a resistance distribution map;

[0149] a second obtaining unit, configured to obtain a preset corrected resistance value, and to draw a segmentation line on the resistance distribution map according to the preset corrected resistance value;

[0150] a third obtaining unit, configured to obtain first position information of each corrected resistance value above the segmentation line in the image and second position information of each corrected resistance value below the segmentation line in the image;

[0151] a first marking unit, configured to mark a plurality of the first position information as white in the image, and to connect a plurality of the first position information marked as white through a horizontal line and a vertical line, to obtain a first region;

[0152] A second marking unit is configured to mark a plurality of the second position information as black in the image, and connect the plurality of the marked black second position information by horizontal lines and vertical lines to obtain a second region.

[0153] A removing unit is configured to remove, in the first region, a region where the first region overlaps with the second region to obtain a high-impedance region.

[0154] The application further provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the PCB high-impedance performance detection method when executing the computer program.

[0155] The application further provides a computer readable storage medium, which stores a computer program, and the computer program implements the steps of the PCB high-impedance performance detection method when executed by a processor.

[0156] Those skilled in the art can understand that all or part of the above-mentioned embodiment methods can be completed by a computer program to instruct related hardware, and the computer program can be stored in a non-volatile computer readable storage medium, and the computer program can include the above-mentioned method embodiments when executed. Any reference to memory, storage, database or other medium provided by the application and used in the embodiments can include non-volatile and / or volatile memory. The non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. The volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (SSRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM) and memory bus dynamic RAM (RDRAM).

[0157] It is to be understood that the terminology "including", "comprising", or any other variation thereof, is intended to cover a non-exclusive inclusion such that process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element preceded by "comprises a... " does not, without more constraints, foreclose the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0158] The above description is merely the preferred embodiments of the present application, and is not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made according to the content of the present application specification and drawings, or directly or indirectly applied to other related technical fields, is also included in the patent protection scope of the present application.

Claims

1. A method for testing the high impedance performance of a PCB board, characterized in that, include: Acquire an image of the PCB board, and obtain multiple preset measurement points based on the image; The actual resistance and actual temperature values ​​of each preset measurement point are obtained, wherein multiple preset measurement points are distributed in an array; Calculate the resistance temperature coefficient for each preset measurement point based on each actual resistance value and the corresponding actual temperature value, and perform temperature compensation on the actual resistance value of each preset measurement point based on the resistance temperature coefficient to obtain multiple corrected resistance values; The multiple corrected resistance values ​​are plotted as a resistance distribution map, and the high impedance region is obtained based on the resistance distribution map; Obtain a preset load application table, and apply a load to a high impedance region according to the preset load application table, wherein the preset load application table includes multiple load values ​​arranged in ascending order; The total signal waveform is acquired in real time when a load is applied to the high-impedance region. The highest peak value and lowest trough value of the total signal waveform are obtained, and the signal amplitude attenuation percentage is calculated based on the highest peak value and lowest trough value. The calculation formula is as follows: Where F(S) represents the percentage of signal amplitude attenuation, Z(G) represents the highest peak value, and Z(D) represents the lowest valley value; Obtain the ideal phase value; The actual phase value is obtained from the total signal waveform, and the phase distortion is obtained from the difference between the actual phase value and the ideal phase value. The noise amplitude at each time point is obtained based on the total signal waveform, and the noise level value is calculated based on multiple noise amplitudes, wherein the calculation formula is: Where Z(S) represents the noise level value, and Z(F) represents the noise level value. m This represents the m-th noise amplitude, where M represents the number of noise amplitudes and m represents the index of the noise amplitude. The first weight for obtaining the percentage of signal amplitude attenuation is obtained, the second weight for obtaining the phase distortion is obtained, and the third weight for obtaining the noise level value is obtained. The performance evaluation value is calculated based on the noise level, phase distortion, signal amplitude attenuation percentage, first weight, second weight, and third weight, wherein the calculation formula is: X(P)=a*F(S)+b*X(S)+c*Z(S); Where X(P) represents the performance evaluation value, Z(S) represents the noise level value, F(S) represents the signal amplitude attenuation percentage, X(S) represents the phase distortion, a represents the first weight, b represents the second weight, and c represents the third weight. Determine whether the performance evaluation value is within a preset range; If the performance evaluation value is within the preset range, the PCB board is judged to have good high impedance performance. If the performance evaluation value is not within the preset range, the PCB board is judged to have poor high impedance performance.

2. The PCB board high impedance performance testing method according to claim 1, characterized in that, The step of calculating the resistance temperature coefficient of each preset measurement point based on each actual resistance value and the corresponding actual temperature value includes: Obtain multiple historical temperature values ​​of the PCB board; Based on each historical temperature value, obtain the corresponding historical resistance value for each preset measurement point; The temperature coefficient of resistance is calculated based on the actual resistance value, actual temperature value, multiple historical temperature values, and historical resistance values, using the following formula: Where W(X) represents the temperature coefficient of resistance, S(D) represents the actual resistance value, and Y(D) represents the resistance value. i Let S(W) represent the i-th historical resistance value, and Y(W) represent the actual temperature value. i This represents the i-th historical temperature value, where i represents the sequence number of the historical resistance value, and n represents the number of historical resistance values.

3. The PCB board high impedance performance testing method according to claim 1, characterized in that, The step of performing temperature compensation on the actual resistance value of each preset measurement point based on the temperature coefficient of resistance to obtain multiple corrected resistance values ​​includes: Obtain the temperature coefficient of resistance and the actual temperature value; Obtain the reference temperature value of the PCB board, and obtain the temperature compensation value based on the reference temperature value, the temperature coefficient of resistance, the actual temperature value, and the actual resistance value; Determine whether the temperature compensation value is a positive number; If the temperature compensation value is positive, the correction resistance value is obtained by subtracting the temperature compensation value from the actual temperature value. If the temperature compensation value is negative, the corrected resistance value is obtained by adding the temperature compensation value to the actual temperature value.

4. The PCB board high impedance performance testing method according to claim 1, characterized in that, The step of plotting a resistance distribution map of the plurality of corrected resistance values ​​and obtaining the high impedance region based on the resistance distribution map includes: Obtain the corresponding temperature value based on each of the corrected resistance values; A resistance distribution coordinate axis is established with temperature as the X-axis and corrected resistance as the Y-axis. Each corrected resistance value and its corresponding temperature value are plotted as a curve on the resistance distribution coordinate axis to obtain a resistance distribution map. Obtain a preset correction resistance value, and draw a dividing line on the resistance distribution diagram according to the preset correction resistance value; Obtain first position information of each corrected resistance value located above the dividing line in the image and second position information of each corrected resistance value located below the dividing line in the image; Multiple first location information items are marked in white in the image, and the multiple first location information items marked in white are connected by horizontal and vertical lines to obtain a first region; Multiple pieces of the second location information are marked in black in the image, and the multiple pieces of the second location information marked in black are connected by horizontal and vertical lines to obtain the second region; The high impedance region is obtained by removing the overlapping area between the first and second regions in the first region.

5. The PCB board high impedance performance testing method according to claim 1, characterized in that, The step of acquiring the total signal waveform when a load is applied to the high-impedance region in real time includes: Obtain the load waveform diagram of the high impedance region within a preset time under each load value; Obtain multiple peak and valley values ​​for each of the load waveforms; For each peak value, obtain the corresponding falling time point; for each trough value, obtain the corresponding rising time point. The overall signal waveform is plotted based on multiple peak values, their corresponding fall times, valley values, and their corresponding rise times.

6. A performance testing system for high impedance of PCB boards, characterized in that, include: The first acquisition module is used to acquire an image of the PCB board and acquire multiple preset measurement points based on the image; The second acquisition module is used to acquire the actual resistance value and actual temperature value of each preset measurement point, wherein multiple preset measurement points are distributed in an array; The calculation module is used to calculate the resistance temperature coefficient of each preset measurement point based on each actual resistance value and the corresponding actual temperature value, and to perform temperature compensation on the actual resistance value of each preset measurement point based on the resistance temperature coefficient to obtain multiple corrected resistance values. A drawing module is used to draw multiple corrected resistance values ​​into a resistance distribution map, and to obtain high impedance regions based on the resistance distribution map; An application module is used to obtain a preset load application table and apply a load to a high-impedance region according to the preset load application table, wherein the preset load application table includes multiple load values ​​arranged in order of magnitude; The third acquisition module is used to acquire the total signal waveform when a load is applied to the high-impedance region in real time, and to acquire the highest peak value and lowest valley value of the total signal waveform. Based on the highest peak value and lowest valley value, the module calculates the signal amplitude attenuation percentage, where the calculation formula is: Where F(S) represents the percentage of signal amplitude attenuation, Z(G) represents the highest peak value, and Z(D) represents the lowest valley value; Obtain the ideal phase value; The actual phase value is obtained from the total signal waveform, and the phase distortion is obtained from the difference between the actual phase value and the ideal phase value. The noise amplitude at each time point is obtained based on the total signal waveform, and the noise level value is calculated based on multiple noise amplitudes, wherein the calculation formula is: Where Z(S) represents the noise level value, and Z(F) represents the noise level value. m This represents the m-th noise amplitude, where M represents the number of noise amplitudes and m represents the index of the noise amplitude. The first weight for obtaining the percentage of signal amplitude attenuation is obtained, the second weight for obtaining the phase distortion is obtained, and the third weight for obtaining the noise level value is obtained. The performance evaluation value is calculated based on the noise level, phase distortion, signal amplitude attenuation percentage, first weight, second weight, and third weight, wherein the calculation formula is: X(P)=a*F(S)+b*X(S)+c*Z(S); Where X(P) represents the performance evaluation value, Z(S) represents the noise level value, F(S) represents the signal amplitude attenuation percentage, X(S) represents the phase distortion, a represents the first weight, b represents the second weight, and c represents the third weight. The judgment module is used to determine whether the performance evaluation value is within a preset range; If the performance evaluation value is within the preset range, the PCB board is judged to have good high impedance performance. If the performance evaluation value is not within the preset range, the PCB board is judged to have poor high impedance performance.

7. The PCB board high impedance performance testing system according to claim 6, characterized in that, The drawing module includes: The first acquisition unit is used to acquire a corresponding temperature value based on each of the corrected resistance values; The plotting unit is used to establish a resistance distribution coordinate axis with temperature value on the X-axis and corrected resistance value on the Y-axis, and to plot each corrected resistance value and its corresponding temperature value on the resistance distribution coordinate axis to obtain a resistance distribution map. The second acquisition unit is used to acquire a preset correction resistance value and draw a dividing line on the resistance distribution diagram according to the preset correction resistance value; The third acquisition unit is used to acquire the first position information of each corrected resistance value located above the dividing line in the image and the second position information of each corrected resistance value located below the dividing line in the image; The first marking unit is used to mark multiple pieces of the first location information as white in the image, and to connect the multiple pieces of first location information marked as white with horizontal and vertical lines to obtain a first region. The second marking unit is used to mark multiple pieces of the second position information as black in the image, and to connect the multiple pieces of the second position information marked as black by horizontal and vertical lines to obtain a second region; The rejection unit is used to reject the overlapping area between the first region and the second region in the first region to obtain a high impedance region.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 5.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 5.

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