Method for quantifying alternating damp heat test intensity of electronic product

Abstract

According to the method for quantifying the alternating damp-heat test strength of the electronic product, parameterized test design is achieved by mining and extracting test key parameter information, intelligent test equipment can be conveniently connected, meanwhile, quantitative calculation of the test strength can be achieved, overall comparison of different test schemes can be supported, and the test efficiency is improved. And tool methods such as DOE (test design) and the like can be used for comparing and screening the optimal test schemes, so that the limitation that the alternating damp-heat test strength cannot be quantified in the prior art is made up. Parameters involved in the method can be extracted from existing test design, existing test methods and steps do not need to be changed and adjusted, and extra test cost does not need to be increased.

Description

Technical Field

[0001] The present invention relates to the technical field of calculating the overall strength of an electronic product in an alternating damp heat test, and in particular to a method for quantifying the strength of an electronic product in an alternating damp heat test. Background Art

[0002] Since electronic products will inevitably be exposed to different temperature and humidity environments during use, in order to verify and enhance the reliability of electronic products in hot and humid environments, especially in high temperature and high humidity environments, environmental tests are usually carried out during the product development stage. Usually, the tests are carried out based on the two alternating damp heat test standards GB / T2423.4-2008 and GJB 150.9A-2009, so as to expose and discover possible design defects in hot and humid environments. However, with the development of new materials, the improvement of equipment accuracy, and the improvement of production processes, the existing alternating damp heat test standards are often not strict enough. Therefore, in actual work, different companies often adjust and change some test parameters in the existing alternating damp heat test standards according to their own product characteristics to conduct customized tests. However, such test design often relies more on the drawing and text description of the test profile, lacks the extraction of test parameters, is not conducive to matching with modern intelligent test equipment, and is difficult to compare the test intensity between different tests, and thus cannot effectively screen out the test design scheme and parameters that are most suitable for exposing product environmental reliability defects.

[0003] There are two main standards for alternating damp heat test currently in use in China, namely GB / T2423.4-2008 "Environmental testing for electrical and electronic products Part 2: Test method Test Db: Alternating damp heat (12h+12h cycle)" (equivalent to IEC 60068-2-30:2005) and military standard GJB 150.9A-2009 "Military equipment laboratory environmental test method Part 9: Damp heat test" (equivalent to the US military standard MIL-STD-810F). The former provides two alternating damp heat test cycles, and reflects the severity of the test through the maximum temperature and the number of cycles. In the standard drawings, the test cycle's heating stage, constant temperature stage, cooling stage, low temperature stage, and corresponding temperature and humidity parameters are marked in the form of a test profile diagram; the latter provides a "damp heat cycle control diagram" as a test profile in the standard, supplemented by text for explanation, such as Figure 1 As shown, the severity of the test is increased by extending the test duration. None of the above standards provide a quantitative method for the test intensity.

[0004] Although the above technology describes the alternating damp heat test process based on text and test profiles, explains the heating stage, constant temperature stage, cooling stage, low temperature stage and the corresponding temperature and humidity parameter requirements, and enhances the severity of the test by increasing the maximum temperature, number of cycles and extending the test duration, the intensity of the specific test, that is, how to quantify and compare the severity, has not been solved, and cannot meet the actual use needs. In particular, at present, with the continuous emergence of new materials, the continuous improvement of equipment accuracy, and the continuous improvement of production processes, the reliability of products in damp heat environments has been effectively enhanced. The existing alternating damp heat test standards are often not strict enough. Therefore, it is often necessary to change the maximum temperature, duration, heating rate, cooling rate, number of test cycles and other parameters to obtain the best alternating damp heat test cycle plan, thereby helping companies to quickly and effectively screen out defects in product environmental reliability and improve product design. If the intensity of the alternating damp heat test cannot be quantified, it is not convenient to effectively connect with the current situation of highly parameterized modern intelligent test equipment, nor is it convenient to compare the test intensity between different tests, and it is difficult to use tools and methods such as DOE (experimental design) to compare and screen the best test plans. Summary of the invention

[0005] The object of the present invention is to provide.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A method for quantifying the strength of an electronic product in a cyclic damp heat test, which is used to quantify the overall strength of the cyclic damp heat test, comprises the following steps:

[0008] Step S1: extract the temperature parameters in the alternating damp heat test scheme, including the highest temperature, the lowest temperature, the heating time and the high temperature maintenance time in a test cycle, and the cooling time and the low temperature maintenance time in a test cycle; Step S2: calculate the temperature intensity parameters of the alternating damp heat test based on the temperature difference between the highest temperature and the lowest temperature, the proportion of the high temperature maintenance time in a test cycle, the average heating rate and the average cooling rate; Step S3: extract the humidity parameters in the alternating damp heat test scheme, including the highest humidity and the lowest humidity in the high humidity stage in a test cycle. degree, the maximum humidity and the minimum humidity in the low humidity stage within a test cycle, and the maintenance time of the high humidity stage and the maintenance time of the low humidity stage within a test cycle; step S4: based on the humidity difference between the maximum humidity and the minimum humidity and the proportion of the high humidity maintenance time within a test cycle, calculate the humidity intensity parameter of the alternating damp heat test; step S5: define and calculate the temperature intensity coupling coefficient and the humidity intensity coupling coefficient; step S6: based on the temperature intensity parameter of the alternating damp heat test, the humidity intensity parameter of the alternating damp heat test, the temperature intensity coupling coefficient and the humidity intensity coupling coefficient, calculate the overall intensity of the alternating damp heat test.

[0009] Preferably, in step S1, the maximum temperature T H , minimum temperature T L , heating time T1, high temperature maintenance time T2, cooling time T3 and low temperature maintenance time T4;

[0010] In step S2, based on the maximum temperature T H With the minimum temperature T L Calculate the temperature difference T v , T v =T H -T L ;

[0011] Based on the high temperature maintenance time T2, calculate the high temperature duration ratio m in a test cycle.

[0012] The average heating rate V is calculated based on the temperature in the heating stage. r ,

[0013] Calculate the average cooling rate V based on the temperature in the cooling stage d ,

[0014] Define the temperature intensity parameter of the alternating damp heat test scheme as X, according to the formula X = T H *T v *V r*V d *m Calculate the temperature intensity parameters of the cyclic damp heat test.

[0015] Preferably, in step S3, the following definitions are made: the maximum humidity and the minimum humidity in the high humidity stage are respectively the high humidity upper limit U H And high humidity lower limit U m The maximum humidity and the minimum humidity in the low humidity stage are respectively the low humidity upper limit U n and low humidity limit U L , high humidity maintenance time U1 and low humidity maintenance time U2;

[0016] In step S4, the humidity difference U is calculated based on the maximum humidity in the high humidity stage and the minimum humidity in the low humidity stage. v , U v =U H -U L ;

[0017] Based on the high humidity maintenance time U1, the proportion of high humidity duration n in a test cycle is calculated.

[0018] Define the humidity intensity parameter of the alternating damp heat test as Y, according to the formula Y = U H [(U H -U n )+(U m -U L )]*U v *nCalculate humidity intensity parameters for cyclic damp heat test.

[0019] Preferably, in step S5, the humidity intensity coupling coefficient P is defined, and is calculated based on 0.5 according to the formula P=0.5-0.05*n, where n is the characteristic number of the protection level of the enclosure to prevent harmful effects on the equipment due to water ingress in GB / T4208-2017 "Enclosure Protection Level (IP Code)", and the numerical range is 0-9; the temperature intensity coupling coefficient Q is defined, and its value is calculated according to the formula Q=1-P.

[0020] Preferably, in step S6, the alternating damp heat test intensity Z is defined according to the formula Calculate the alternating damp heat test intensity; where T is the running time of one test cycle, and S is the total number of running times of the damp heat cycle in one test cycle.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) The method of the present invention realizes parameterized test design by mining and extracting key test parameter information, which is convenient for connecting intelligent test equipment and can realize quantitative calculation of test intensity. It can support overall comparison of different test schemes and can also use tools and methods such as DOE (experimental design) to compare and screen the best test schemes, thus making up for the limitation of the prior art that the intensity of the alternating damp heat test cannot be quantified.

[0023] (2) The present invention can realize the quantitative evaluation of the overall strength of the alternating damp heat test. On the one hand, it is conducive to the realization of parameterized test design and is convenient for connecting intelligent test equipment. On the other hand, it also supports the overall comparison of different test schemes, and at the same time, it also enhances the applicability of tools and methods such as DOE (experimental design) in the process of screening the best test scheme.

[0024] (3) The parameters involved in the method of the present invention can all be extracted from the existing experimental design, so there is no need to change or adjust the current experimental methods and steps, and no additional experimental costs are required. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is an alternating damp heat test section using the GJB 150.9A-2009 standard in the prior art;

[0026] Figure 2 A flowchart of a method for quantifying the alternating damp heat test strength of an electronic product provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0028] like Figure 2 As shown, a method for quantifying the strength of an electronic product in a cyclic damp heat test disclosed in the present invention is used to quantify the overall strength of the cyclic damp heat test, including the following steps:

[0029] Step S1: Based on the humidity and heat cycle control diagram and text description in the humidity and heat test standard GJB 150.9A-2009, extract the temperature parameters in the humidity and heat test scheme, including the maximum temperature T in the humidity and heat test scheme. H , minimum temperature T L , the heating time T1 and high temperature maintenance time T2 within a test cycle, and the cooling time and low temperature maintenance time T4 within a test cycle.

[0030] High temperature T H : The highest temperature in the test plan.

[0031] Low temperature T L : The lowest temperature in the test plan.

[0032] Heating time T1: the time it takes to rise from the lowest temperature to the highest temperature in one cycle.

[0033] High temperature maintenance time T2: the duration of maintaining high temperature in one cycle.

[0034] Cooling time T3: the time it takes to drop from the highest temperature to the lowest temperature in one cycle.

[0035] Low temperature maintenance time T4: the length of time the high temperature is maintained in one cycle.

[0036] Step S2: Based on the maximum temperature T H With the minimum temperature T L Calculate the temperature difference T v , T v =T H -T L ;

[0037] Based on the high temperature maintenance time T2, calculate the high temperature duration ratio m in a test cycle.

[0038] The average heating rate V is calculated based on the temperature in the heating stage. r ,

[0039] Calculate the average cooling rate V based on the temperature in the cooling stage d ,

[0040] Define the temperature intensity parameter of the alternating damp heat test scheme as X,

[0041] According to the formula X = T H *T v *V r *V d *m Calculate the temperature intensity parameters of the cyclic damp heat test.

[0042] Step S3: Extract humidity parameters in the alternating damp heat test scheme, including the maximum humidity in the high humidity stage within a test cycle, i.e., the upper limit of high humidity U H and the minimum humidity, i.e. the lower limit of high humidity U m , the maximum humidity in the low humidity stage during a test cycle is the low humidity upper limit U n and the minimum humidity, i.e. the lower limit of low humidity U L And the high humidity maintenance time U1 and low humidity maintenance time U2 within a test cycle.

[0043] High humidity limit U H: The highest humidity during the high humidity phase of a cycle, that is, the highest humidity in the test plan.

[0044] High humidity lower limit U m : The lowest humidity during the high humidity phase of a cycle.

[0045] Low humidity upper limit U n : The maximum humidity during the low humidity phase of a cycle.

[0046] Low humidity limit U L : The lowest humidity during the low humidity phase of a cycle, that is, the lowest humidity in the test plan.

[0047] High humidity maintenance time U1: the duration of maintaining high humidity in one cycle.

[0048] Low humidity maintenance time U2: the duration of maintaining low humidity in one cycle.

[0049] Step S4: Calculate the humidity difference U based on the maximum humidity in the high humidity stage and the minimum humidity in the low humidity stage v , U v =U H -U L ;

[0050] Based on the high humidity maintenance time U1, the proportion of high humidity duration n in a test cycle is calculated.

[0051] Define the humidity intensity parameter of the alternating damp heat test as Y, according to the formula Y = U H [(U H -U n )+(U m -U L )]*U v *n calculates the humidity intensity parameters of the alternating damp heat test. Step S5: define the humidity intensity coupling coefficient P, taking 0.5 as the benchmark, and calculate according to the formula P = 0.5-0.05*n, where n is the characteristic number of the protection level of the enclosure to prevent the harmful effects of water on the equipment in GB / T 4208-2017 "Enclosure Protection Level (IP Code)", and the value range is 0-9 (according to the enclosure protection level of the smart meter, the test intensity calculation is performed to obtain the test intensity value of the current scheme;); define the temperature intensity coupling coefficient Q, and its value is calculated according to the formula Q = 1-P.

[0052] Furthermore, in this embodiment, when calculating the temperature and humidity intensity coupling coefficient, in addition to calculating the weight of the temperature and humidity intensity based on the casing protection level in the GB / T 4208-2017 standard, the weight can also be determined based on the ease with which the product is affected by moisture or the sensitivity to ambient humidity.

[0053] Step S6: Based on the temperature intensity parameter of the alternating damp heat test, the humidity intensity parameter of the alternating damp heat test, the temperature intensity coupling coefficient and the humidity intensity coupling coefficient, define the alternating damp heat test intensity Z according to the formula Calculate the alternating damp heat test intensity; where T is the running time of one test cycle, and S is the total number of running times of the damp heat cycle in one test cycle.

[0054] By adjusting the variables that affect the intensity value of the cyclic damp heat test and the test intensity, the optimal cyclic damp heat test design scheme is screened and compared according to the exposure rate of product design reliability design defects at different intensities.

[0055] Furthermore, in this embodiment, when calculating the overall strength of the damp heat test, the running time T of a single cycle and the total number of running times S of the damp heat cycle are not considered, so that the calculation and comparison of the test strength of a single cycle can be realized, and the function of quantifying the test strength is also available.

[0056] In summary, the present invention extracts parameter information about temperature and humidity in the alternating damp heat test scheme respectively, calculates their respective test strengths and then couples the two; based on the product's shell protection (waterproof) level or the product's ease of getting wet and its sensitivity to ambient humidity, the weight distribution of temperature and humidity effects in the test intensity is adjusted.

[0057] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0058] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for quantifying the strength of an electronic product in a damp heat cycle test, which is used to quantify the overall strength of the damp heat cycle test, and is characterized in that: The steps include: Step S1: extracting temperature parameters in the alternating damp heat test scheme, including the highest temperature, the lowest temperature, the heating time and the high temperature maintenance time in one test cycle, and the cooling time and the low temperature maintenance time in one test cycle; Step S2: Calculate the temperature intensity parameter of the alternating damp heat test based on the temperature difference between the highest temperature and the lowest temperature, the proportion of the high temperature duration in a test cycle, the average heating rate and the average cooling rate; Step S3: extracting humidity parameters in the alternating damp heat test scheme, including the maximum humidity and the minimum humidity in the high humidity stage in a test cycle, the maximum humidity and the minimum humidity in the low humidity stage in a test cycle, and the maintenance time of the high humidity stage and the maintenance time of the low humidity stage in a test cycle; Step S4: Calculating the humidity intensity parameter of the alternating damp heat test based on the humidity difference between the maximum humidity and the minimum humidity and the proportion of the high humidity duration within a test cycle; Step S5: defining and calculating the temperature intensity coupling coefficient and the humidity intensity coupling coefficient; Step S6: Calculate the overall strength of the alternating damp heat test based on the temperature strength parameter of the alternating damp heat test, the humidity strength parameter of the alternating damp heat test, the temperature strength coupling coefficient and the humidity strength coupling coefficient.

2. A method for quantifying the strength of an electronic product under alternating damp heat test according to claim 5, characterized in that: In step S1, the maximum temperature T is defined as follows: H , minimum temperature T L , heating time T1, high temperature maintenance time T2, cooling time T3 and low temperature maintenance time T4; In step S2, based on the maximum temperature T H With the minimum temperature T L Calculate the temperature difference T v , T v =T H -T L ; Based on the high temperature maintenance time T2, calculate the high temperature duration ratio m in a test cycle. The average heating rate V is calculated based on the temperature in the heating stage. r , Calculate the average cooling rate V based on the temperature in the cooling stage d , Define the temperature intensity parameter of the alternating damp heat test scheme as X, According to the formula X = T H *T v *V r *V d *m Calculate the temperature intensity parameters of the cyclic damp heat test.

3. A method for quantifying the strength of an electronic product under alternating damp heat test according to claim 1, characterized in that: In step S3, the maximum humidity and the minimum humidity in the high humidity stage are defined as follows: H And high humidity lower limit U m The maximum humidity and the minimum humidity in the low humidity stage are respectively the low humidity upper limit U n and low humidity limit U L , high humidity maintenance time U1 and low humidity maintenance time U2; In step S4, the humidity difference U is calculated based on the maximum humidity in the high humidity stage and the minimum humidity in the low humidity stage. v , U v =U H -U L ; Based on the high humidity maintenance time U1, the proportion of high humidity duration n in a test cycle is calculated. Define the humidity intensity parameter of the alternating damp heat test as Y, According to the formula Y = U H [(U H -U n )+(U m -U L )]*U v *nCalculate humidity intensity parameters for cyclic damp heat test.

4. The method for quantifying the strength of an electronic product under alternating damp heat test according to claim 1, characterized in that: In the step S5, the humidity intensity coupling coefficient P is defined, and is calculated based on 0.5 according to the formula P=0.5-0.05*n, where n is the characteristic number of the protection level of the enclosure to prevent harmful effects on the equipment due to water ingress in GB / T 4208-2017 "Enclosure Protection Level (IP Code)", and the value range is 0-9; The temperature intensity coupling coefficient Q is defined, and its value is calculated according to the formula Q=1-P.

5. The method for quantifying the strength of an electronic product under alternating damp heat test according to claim 1, characterized in that: In step S6, the alternating damp heat test intensity Z is defined as follows: Calculate the intensity of the alternating damp heat test; Where T is the running time of a test cycle, and S is the total number of wet heat cycles in a test cycle.

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