Repetitive peak isolation voltage setting method and system for optical isolation device

Abstract

The invention discloses a repetitive peak isolation voltage formulating method and system for an optical isolation device, and the method comprises the steps: carrying out the statistics and distribution parameter estimation of the end-of-life time data of the optical isolation device through Weibull distribution, and obtaining a fitting probability graph; based on the fitting probability graph, obtaining failure time of specified failure rates under different test voltages; obtaining a life time prediction map of the optoisolator under different specific voltages based on the failure time of the specified failure rate under different test voltages; and based on the life time prediction map of the optical isolator under different specific voltages, analyzing the life of the device under the specific repeated peak isolation voltage. The invention provides a data analysis technology to obtain an accurate VIORM value and predicted life, so that life prediction of the optical isolator in different scenes is more accurate.

Description

Technical Field

[0001] The invention belongs to the field of electronic component testing and reliability evaluation, and in particular relates to a method and system for formulating a repetitive peak isolation voltage for an optical isolation device. Background Art

[0002] Optical isolator is a device that uses optical signals for electrical isolation and is widely used in communications, industrial control, medical equipment and other fields. Its main function is to achieve electrical isolation through optical signal transmission to prevent high voltage or current from damaging sensitive electronic equipment. Optical isolator is usually composed of light-emitting diodes and phototransistors, and achieves electrical isolation through the transmission of optical signals. In existing solutions, there is a lack of methods for formulating repetitive peak isolation voltage for optical isolators.

[0003] At present, there is no unified standard for the end-of-life test of optical isolators. The two main methods used are accelerated aging test and cycle life test:

[0004] Accelerated aging test: Accelerate the aging process of the optical isolator by applying an environment that is more severe than normal use conditions (such as high temperature, high humidity, etc.), so as to predict its life in a shorter time. This method can effectively simulate the aging process of the optical isolator in long-term use, but it requires precise control of test conditions and parameters.

[0005] Cycle life test: Repeat the working cycle of the optical isolator until it fails. For example, the optical power switching operation is repeated to simulate the working conditions in actual use. This method can directly reflect the life of the optical isolator in actual use, but the test time is longer. Summary of the invention

[0006] In view of the shortcomings of the prior art in the end-of-life test of optical isolators, the present invention proposes a method and system for formulating a repetitive peak isolation voltage for optical isolation devices, designs an analysis method for end-of-life testing, and analyzes the life of the device under a specific repetitive peak isolation voltage through the data obtained from the end-of-life test, thereby providing a scientific basis for product design and quality control, and ensuring the long-term stability and safety of optical isolators in practical applications.

[0007] To achieve the above object, the present invention provides the following solutions:

[0008] A method for formulating a repetitive peak isolation voltage for an optical isolation device comprises the following steps:

[0009] The Weibull distribution is used to perform statistics and distribution parameter estimation on the end-of-life time data of optical isolation devices, and a fitting probability graph is obtained;

[0010] Based on the fitting probability graph, the failure time of the specified failure rate under different test voltages is obtained;

[0011] Based on the failure time of the specified failure rate under different test voltages, the life time prediction diagram of the optical isolator under different specific voltages is obtained;

[0012] Based on the life prediction diagram of the optical isolator under different specific voltages, the life of the device under a specific repetitive peak isolation voltage is analyzed.

[0013] Preferably, the method of using Weibull distribution to perform statistics on the end-of-life time data of the optical isolation device and estimate the distribution parameters to obtain the fitting probability graph includes:

[0014] By using the failure time data under three different preset voltages, the least square method or maximum likelihood estimation method is used to estimate the distribution parameters and obtain the shape parameters and scale parameters;

[0015] The fitted Weibull probability density function is obtained based on the estimated values ​​of the shape parameter and scale parameter;

[0016] The fitting effect is verified by drawing a Weibull probability plot.

[0017] Preferably, the method of estimating the distribution parameters by using the least squares method or the maximum likelihood estimation method based on the failure time data under three different preset voltages to obtain the shape parameters and scale parameters includes:

[0018]

[0019] Preferably, based on the failure time of the specified failure rate under different test voltages, the method for obtaining the life time prediction diagram of the optical isolator under different specific voltages includes: after selecting three groups of failure times under different voltages, fitting the life prediction curves under different voltages.

[0020] Preferably, after selecting three groups of failure times under different voltages, the method for fitting the life prediction curves under different voltages includes:

[0021] For SiO2 optical isolators, an exponential model is used:

[0022] L=ce kV

[0023] Wherein, L is the life, i.e. the failure time based on the specified failure rate under different test voltages, V is the voltage, and c and k are parameters to be determined;

[0024] Using the exponential model, three equations are obtained through three different sets of experimental data and three different sets of K values ​​are obtained by combining them two by two:

[0025]

[0026] After the k value is determined, the three sets of data are used to perform exponential fitting on the parameter c to obtain the final three sets of life curves;

[0027] Select the claimed lifespan that the manufacturer wants to achieve from the three sets of lifespan curves and find the corresponding voltage V ware out , take the fitting result with the minimum voltage.

[0028] Preferably, after selecting three groups of failure times under different voltages, the method for fitting life prediction curves under different voltages also includes:

[0029] For non-SiO2 compound optical isolators, nonlinear models are applicable;

[0030] L=ce kV-n

[0031] Wherein, L is the life, i.e. the failure time based on the specified failure rate under different test voltages, V is the voltage, and c, n, and k are parameters to be determined;

[0032] Using the nonlinear model, the value of n is solved by combining the equations obtained from the fitting data of three sets of different voltages to obtain a nonlinear equation, which is expressed as:

[0033]

[0034] After obtaining the specific value of parameter n, the life curve is obtained by performing nonlinear fitting on parameters c and k;

[0035] Select the manufacturer's claimed life span in the life span curve and find the corresponding voltage V ware out , take the fitting result with the minimum voltage.

[0036] The present invention also discloses a repetitive peak isolation voltage formulation system for optical isolation devices, comprising: an estimation module, a selection module, a fitting module and an analysis module;

[0037] The estimation module is used to perform statistics and distribution parameter estimation on the end-of-life time data of the optical isolation device using Weibull distribution to obtain a fitting probability graph;

[0038] The selection module is used to obtain the failure time of the specified failure rate under different test voltages based on the fitting probability graph;

[0039] The fitting module is used to obtain a life time prediction diagram of the optical isolator under different specific voltages based on the failure time of the specified failure rate under different test voltages;

[0040] The analysis module is used to analyze the life of the device under a specific repetitive peak isolation voltage based on the life time prediction diagram of the optical isolator under different specific voltages.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] Accurate data analysis: The present invention introduces Weibull distribution and maximum likelihood estimation method as well as mathematical models of different materials in the end-of-life test data analysis of optical isolation devices, thereby improving the accuracy of data processing and result analysis and ensuring the reliability of life prediction.

[0043] Reliable result verification: The present invention verifies the accuracy of the data analysis results through goodness-of-fit tests and Weibull probability plots to ensure the reliability of the test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solution of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0045] Figure 1 The present invention is a flowchart of a method for formulating a repetitive peak isolation voltage for an optical isolation device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0048] Embodiment 1

[0049] V IORM (Maximum Repetitive Peak Isolation Voltage) is an important voltage parameter, which represents the isolation voltage capability of the device.

[0050] V IORM Refers to the maximum repetitive peak isolation voltage that a device can withstand during its lifetime. This is a peak voltage specified by the manufacturer that indicates the specific withstand capability of the device under repetitive peak voltage. VIORM Reflects the maximum periodic voltage that the device can safely withstand under normal operating conditions. This includes all repetitive transient voltages but excludes non-repetitive transient voltages.

[0051] In end-of-life testing, the optoisolator is subjected to accelerated stress tests (such as time-dependent dielectric breakdown, TDDB) where a voltage higher than the working isolation voltage is applied and the breakdown time is recorded and extrapolated to a voltage vs. time graph to determine the predicted lifetime at different voltages.

[0052] The purpose of the present invention is to address the shortcomings of the prior art in the end-of-life test of optical isolators and to propose a data analysis technology to obtain accurate V IORM The value and predicted life of the optical isolator can be more accurately predicted in different scenarios. Specific goals include:

[0053] Improve data analysis methods: Introduce Weibull distribution and maximum likelihood estimation, fit different parameters to different models, and improve the accuracy of data processing and result analysis.

[0054] Standardized test methods: Develop a unified data processing specification process to ensure that the test results under different test methods and conditions are comparable and consistent.

[0055] By achieving the above objectives, the present invention will significantly improve the accuracy of end-of-life testing of optical isolators.

[0056] like Figure 1 As shown, the present invention provides a method for formulating a repetitive peak isolation voltage for an optical isolation device, comprising the following steps:

[0057] The Weibull distribution is used to perform statistics and distribution parameter estimation on the end-of-life time data of optical isolation devices, and a fitting probability graph is obtained;

[0058] Based on the fitting probability graph, the failure time of the specified failure rate under different test voltages is obtained;

[0059] Based on the failure time of the specified failure rate under different test voltages, the life time prediction diagram of the optical isolator under different specific voltages is obtained;

[0060] Based on the life prediction diagram of the optical isolator under different specific voltages, the life of the device under a specific repetitive peak isolation voltage is analyzed.

[0061] The specific implementation process is as follows:

[0062] First, the Weibull distribution is used to perform statistics and estimate distribution parameters of the end-of-life time data. The probability distribution function of the Weibull distribution is as follows:

[0063]

[0064] Among them, in the application scenario of life test, x is the failure time of the device in the test, λ>0 is the proportional parameter, and k>0 is the shape parameter.

[0065] 1. After obtaining sufficient failure time data under three different voltages, the shape parameters and scale parameters are estimated using the least squares method or the maximum likelihood estimation method. Take the maximum likelihood estimation method as an example:

[0066]

[0067] The shape parameter and scale parameter are obtained by differentiation:

[0068]

[0069] The fitted Weibull probability density function is obtained through the parameter estimation value. Then the fitting effect is verified by drawing the Weibull probability graph (the X-axis of the Weibull distribution graph is time and the Y-axis is failure rate).

[0070] 2. Read out the failure time of the specified failure rate under different test voltages in the fitting probability diagram. For basic insulation, select the point with a failure rate of 1000ppm for data selection, and for reinforced insulation, select 1ppm.

[0071] 3. In the obtained Weibull distribution diagram, read the life time corresponding to the three sets of voltages under a specific failure rate, obtain three sets of L (life time) and V (voltage) data, and then fit the device life curve. For different types of optical isolators, there are corresponding different fitting models:

[0072] 1. For SiO2 optical isolators, the exponential model is applicable;

[0073] L=ce kV

[0074] Among them, L is the life (i.e. the failure time of step 2), V is the voltage, and c and k are unknown parameters. By combining three equations obtained from three different sets of experimental data, three different sets of K values ​​can be obtained:

[0075]

[0076] After the k value is determined, the three sets of data are used to perform exponential fitting on the parameter c to obtain the final three sets of life curves. Select the manufacturer's declared life to be achieved in the three sets of life curves and find the corresponding voltage V ware out, take the most severe condition, that is, the one with the smallest voltage. For the coupler, a safety factor needs to be extrapolated to ensure the reliability of the device. The required V IORM That is V ware out / 1.2.

[0077] 2. For non-SiO2 compound optical isolators, nonlinear models are applicable;

[0078] L=ce kV-n

[0079] Among them, L is the lifespan, V is the voltage, and c, n, and k are unknown parameters.

[0080] Unlike the exponential model, the value of n can be obtained by combining the equations obtained from the three sets of data to form a nonlinear equation, expressed as:

[0081]

[0082] Mathematical tools can be used to solve the numerical solution of n. After obtaining the specific value of parameter n, the life curve can be obtained by performing nonlinear fitting on parameters c and k. IORM The extrapolation method is consistent with the exponential model.

[0083] Embodiment 2

[0084] The present invention also discloses a repetitive peak isolation voltage formulation system for optical isolation devices, comprising: an estimation module, a selection module, a fitting module and an analysis module;

[0085] The estimation module is used to perform statistics and distribution parameter estimation on the end-of-life time data of the optical isolation device using Weibull distribution to obtain a fitting probability graph;

[0086] The selection module is used to obtain the failure time of the specified failure rate under different test voltages based on the fitting probability graph;

[0087] The fitting module is used to obtain the life time prediction diagram of the optical isolator under different specific voltages based on the failure time of the specified failure rate under different test voltages;

[0088] The analysis module is used to analyze the life of the device under a specific repetitive peak isolation voltage based on the life time prediction diagram of the optical isolator under different specific voltages.

[0089] The embodiments described above are only descriptions of the preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for formulating a repetitive peak isolation voltage for an optical isolation device, characterized in that: The following steps are involved: The Weibull distribution is used to perform statistics and distribution parameter estimation on the end-of-life time data of optical isolation devices, and a fitting probability graph is obtained; Based on the fitting probability graph, the failure time of the specified failure rate under different test voltages is obtained; Based on the failure time of the specified failure rate under different test voltages, the life time prediction diagram of the optical isolator under different specific voltages is obtained; Based on the life prediction diagram of the optical isolator under different specific voltages, the life of the device under a specific repetitive peak isolation voltage is analyzed.

2. The method for formulating a repetitive peak isolation voltage for an optical isolation device according to claim 1, characterized in that: The method of using Weibull distribution to perform statistics and distribution parameter estimation on the end-of-life time data of optical isolation devices and obtain a fitting probability graph includes: By using the failure time data under three different preset voltages, the least square method or maximum likelihood estimation method is used to estimate the distribution parameters and obtain the shape parameters and scale parameters; The fitted Weibull probability density function is obtained based on the estimated values ​​of the shape parameter and scale parameter; The fitting effect is verified by drawing a Weibull probability plot.

3. The method for formulating a repetitive peak isolation voltage for an optical isolation device according to claim 2, characterized in that: By using the failure time data under three different preset voltages, the least square method or the maximum likelihood estimation method is used to estimate the distribution parameters, and the method for obtaining the shape parameters and scale parameters includes:

4. The method for formulating a repetitive peak isolation voltage for an optical isolation device according to claim 1, characterized in that: The method for obtaining a life prediction diagram of an optical isolator under different specific voltages based on the failure time of a specified failure rate under different test voltages includes: selecting three groups of failure times under different voltages and fitting life prediction curves under different voltages.

5. The method for formulating a repetitive peak isolation voltage for an optical isolation device according to claim 4, characterized in that: After selecting three groups of failure times under different voltages, the method for fitting the life prediction curve under different voltages includes: For SiO2 optical isolators, an exponential model is used: What? kV Wherein, L is the life, i.e. the failure time based on the specified failure rate under different test voltages, V is the voltage, and c and k are parameters to be determined; Using the exponential model, three equations are obtained through three different sets of experimental data and three different sets of K values ​​are obtained by combining them two by two: After the k value is determined, the three sets of data are used to perform exponential fitting on the parameter c to obtain the final three sets of life curves; Select the claimed lifespan that the manufacturer wants to achieve from the three sets of lifespan curves and find the corresponding voltage V wareout , take the fitting result with the minimum voltage.

6. The method for formulating a repetitive peak isolation voltage for an optical isolation device according to claim 4, characterized in that: After selecting three groups of failure times under different voltages, the method of fitting the life prediction curve under different voltages also includes: For non-SiO2 compound optical isolators, nonlinear models are applicable; Wherein, L is the life, i.e. the failure time based on the specified failure rate under different test voltages, V is the voltage, and c, n, and k are parameters to be determined; Using the nonlinear model, the value of n is solved by combining the equations obtained from the fitting data of three sets of different voltages to obtain a nonlinear equation, which is expressed as: After obtaining the specific value of parameter n, the life curve is obtained by performing nonlinear fitting on parameters c and k; Select the manufacturer's claimed life span in the life span curve and find the corresponding voltage V wareout , take the fitting result with the minimum voltage.

7. A system for developing a repetitive peak isolation voltage for an optical isolation device, characterized in that: include: Estimation module, selection module, fitting module and analysis module; The estimation module is used to perform statistics and distribution parameter estimation on the end-of-life time data of the optical isolation device using Weibull distribution to obtain a fitting probability graph; The selection module is used to obtain the failure time of the specified failure rate under different test voltages based on the fitting probability graph; The fitting module is used to obtain a life time prediction diagram of the optical isolator under different specific voltages based on the failure time of the specified failure rate under different test voltages; The analysis module is used to analyze the life of the device under a specific repetitive peak isolation voltage based on the life time prediction diagram of the optical isolator under different specific voltages.

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