CN-122017413-A - Annular piezoresistor aging performance test method based on data analysis

CN122017413ACN 122017413 ACN122017413 ACN 122017413ACN-122017413-A

Abstract

The application relates to the technical field of electronic component testing, in particular to a method for testing ageing performance of an annular piezoresistor based on data analysis. The method comprises the steps of applying an excitation signal consisting of high-voltage pulses and high-frequency sinusoidal signals to an annular piezoresistor in a constant temperature environment, synchronously collecting voltage and current signals, extracting time domain thermal characteristics and frequency domain structural characteristics, calculating the ratio of the time domain thermal characteristic change rate to the frequency domain structural characteristic change rate to generate a differential index, executing a hierarchical modulation strategy on waveform parameters of the high-voltage pulses of the next period based on a numerical value interval where the differential index is located, calculating time derivatives of the two types of characteristics in real time, and terminating an aging test and outputting qualified judgment when absolute values of the two types of characteristics are lower than a preset convergence threshold. According to the application, through decoupling thermal effect and structural damage, the self-adaptive aging screening of the annular piezoresistor is realized, and the accuracy and safety of the test are improved.

Inventors

ZHOU BINYANG
XUE TONG
Che Gaofa

Assignees

东莞易力禾电子有限公司

Dates

Publication Date: 20260512
Application Date: 20260205

Claims (10)

1. The method for testing the aging performance of the annular piezoresistor based on data analysis is characterized by comprising the following steps of: in a constant temperature environment, applying an excitation signal to the annular piezoresistor, wherein the excitation signal consists of periodic high-voltage pulses and high-frequency sinusoidal signals overlapped in the gaps of the high-voltage pulses; Synchronously collecting voltage and current signals of the annular piezoresistor, and extracting time domain thermal characteristics and frequency domain structural characteristics, wherein the time domain thermal characteristics are charge relaxation constants, and the frequency domain structural characteristics are third harmonic distortion degrees calculated based on response data of the high-frequency sinusoidal signals; calculating the ratio of the change rate of the time domain thermal characteristics to the change rate of the frequency domain structural characteristics, generating a differential index, and executing a hierarchical modulation strategy on waveform parameters of the next periodic high-voltage pulse based on a numerical interval in which the differential index is located; and in the process of executing the steps, calculating the time derivative of the time domain thermal characteristic and the frequency domain structural characteristic in real time, and terminating the aging test and outputting the qualification judgment when the absolute values of the time domain thermal characteristic and the frequency domain structural characteristic are lower than a preset convergence threshold.
2. The method for testing the aging performance of the annular piezoresistor based on data analysis according to claim 1, wherein the step of generating the excitation signal comprises the steps of: Presetting a basic clock period, and outputting a rectangular wave high-voltage pulse in a duty cycle conduction period of the basic clock period, wherein the amplitude of the high-voltage pulse is set as the nominal voltage-sensitive voltage of the annular piezoresistor; and in the duty ratio turn-off period of the basic clock period, firstly, the control circuit enters a high impedance state to collect a voltage attenuation waveform, outputs zero volt bias voltage after the collection is completed, and superimposes the high-frequency sinusoidal signal on the zero bias voltage.
3. The method for testing the aging performance of the annular piezoresistor based on data analysis according to claim 1, wherein the calculation process of the time domain thermal characteristics comprises the following steps: Intercepting voltage attenuation waveform data after the high-voltage pulse falling edge; constructing a mathematical model based on an exponential decay law, and mapping the voltage decay waveform data to the mathematical model by using a least square method; The time constant in the mathematical model is extracted and determined as the charge relaxation constant.
4. The method for testing the aging performance of the annular piezoresistor based on data analysis according to claim 1, wherein the calculating process of the frequency domain structural characteristics comprises the following steps: Extracting a current response data sequence under the excitation of the high-frequency sinusoidal signal; performing fast Fourier transform on the current response data sequence to separate fundamental component amplitude and third harmonic component amplitude; a ratio of the third harmonic component amplitude to the fundamental component amplitude is calculated and the ratio is determined as the third harmonic distortion.
5. The method for testing the aging performance of the annular piezoresistor based on data analysis according to claim 1, wherein the calculating process of the differentiation index comprises the following steps: acquiring the absolute value of the relative variation of the charge relaxation constant of the current period relative to the initial period as a molecular term; acquiring an absolute value of the third harmonic distortion degree of the current period relative to the variation quantity of the initial period, and superposing a non-zero regularization factor as a denominator term; And calculating the ratio of the molecular term to the denominator term to obtain the differentiation index, wherein the differentiation index is positively correlated with the variation amplitude of the charge relaxation constant and negatively correlated with the fluctuation amplitude of the third harmonic distortion degree.
6. The method for testing the aging performance of the annular piezoresistor based on data analysis according to claim 1, wherein the hierarchical modulation strategy comprises: and increasing the high-voltage pulse interval time of the next period, and keeping the amplitude of the high-voltage pulse unchanged until the differential index falls back below the first preset threshold value. And if the differential index is smaller than a second preset threshold value, judging that the current state is a structural aging dominant state, controlling the signal generator to execute stress screening logic, and improving the amplitude of the high-voltage pulse or increasing the pulse width of the high-voltage pulse so as to accelerate the evolution of the potential defect area, wherein the second preset threshold value is smaller than the first preset threshold value.
7. The method for testing the aging performance of the annular piezoresistor based on data analysis of claim 6, wherein the hierarchical modulation strategy further comprises: If the differentiation index is not smaller than the second preset threshold value and not larger than the first preset threshold value, judging that the current state is a stable evolution state, keeping the high-voltage pulse waveform parameters of the current period unchanged, and continuing to execute the aging test of the next period.
8. The method for testing the aging performance of the annular piezoresistor based on data analysis according to claim 7, wherein in performing the hierarchical modulation strategy, the method further comprises: the method comprises the steps of monitoring the leakage current value of the annular piezoresistor in real time, if the leakage current value exceeds a preset safety cut-off threshold value or the variation of the third harmonic distortion degree in a single test period exceeds a preset mutation threshold value, generating a defect rejection instruction, cutting off the excitation signal, terminating the test and marking the annular piezoresistor which is currently tested as a defective product.
9. The method for testing the aging performance of the annular piezoresistor based on data analysis according to claim 1, wherein the step of terminating the aging test comprises the steps of: Constructing a sliding time window containing the latest N test periods; Calculating the slope of the change curve of the time domain thermal characteristic and the slope of the change curve of the frequency domain structural characteristic in the sliding time window respectively; And only when the absolute value of the slope of the change curve of the time domain thermal characteristic is smaller than a first convergence factor and the absolute value of the slope of the change curve of the frequency domain structural characteristic is smaller than a second convergence factor, judging that the aging state reaches a steady state, and triggering the qualification judgment.
10. The method for testing the aging performance of the annular piezoresistor based on data analysis according to claim 7, wherein the first preset threshold and the second preset threshold comprise: establishing a pure thermal excitation experimental group, applying only temperature field change to a sample without applying high-voltage pulse, counting probability density distribution of a differential index calculated in the state, and setting the lower limit of a confidence interval of the probability density distribution as the first preset threshold; and establishing a defect damage experiment group, applying destructive high-voltage pulse to a sample until breakdown, retrospectively analyzing an average value of differential indexes in a preset time period before breakdown, and setting the average value as the second preset threshold value.

Description

Annular piezoresistor aging performance test method based on data analysis Technical Field The application relates to the technical field of electronic component testing. More particularly, the application relates to a method for testing the aging performance of an annular piezoresistor based on data analysis. Background The ring piezoresistor is used as an important overvoltage protection element in a power system and electronic equipment, and the ageing performance of the ring piezoresistor is directly related to the safe and reliable operation of the equipment. In practical application, the piezoresistor is subjected to the combined action of voltage stress and thermal stress for a long time, and performance degradation can gradually occur, and the phenomena of leakage current increase, voltage-sensitive voltage drift and the like are shown. Therefore, the voltage dependent resistor is subjected to ageing performance test screening before leaving the factory, and the potential defective products are removed, so that the voltage dependent resistor is a key link for guaranteeing the product quality. The prior voltage dependent resistor aging test technology generally adopts a single excitation mode of constant voltage stress or constant temperature stress, and evaluates the aging degree by monitoring the change of leakage current or voltage dependent voltage. The method has obvious limitations that on one hand, reversible performance drift caused by a thermal effect and irreversible aging caused by microstructure damage are difficult to distinguish effectively by a single excitation mode, misjudgment is easy to cause, and on the other hand, fixed test parameters cannot be adjusted in a self-adaptive mode according to the actual state of a tested sample, so that the test time is overlong or the test strength is insufficient. In addition, the traditional method mainly relies on monitoring time domain parameters, and characterization information of nonlinear characteristics of the piezoresistor in a frequency domain is ignored. When the grain boundary structure in the piezoresistor is degraded, the nonlinear volt-ampere characteristic of the piezoresistor is changed, and the change is expressed as a change of harmonic components in a frequency domain. What is needed is a method that can integrate time domain and frequency domain features, realize decoupling discrimination of thermal effect and structural aging, and adaptively adjust test parameters according to actual states, so as to solve the problems of low test efficiency and poor discrimination accuracy in the prior art. Disclosure of Invention The application aims to provide a method for testing the aging performance of an annular piezoresistor based on data analysis, which is used for solving the problem of low efficiency caused by distinguishing thermal effect from structural aging and fixing test parameters in the prior art. The application provides a method for testing ageing performance of an annular piezoresistor based on data analysis, which comprises the steps of applying an excitation signal to the annular piezoresistor in a constant temperature environment, synchronously collecting voltage and current signals of the annular piezoresistor and extracting time domain thermal characteristics and frequency domain structural characteristics, wherein the time domain thermal characteristics are charge relaxation constants, the frequency domain structural characteristics are third harmonic distortion degrees calculated based on response data of the high-frequency sinusoidal signals, calculating the ratio of the change rate of the time domain thermal characteristics to the change rate of the frequency domain structural characteristics, generating a differentiation index, executing a hierarchical modulation strategy on waveform parameters of a next periodic high-voltage pulse based on a numerical range where the differentiation index is located, calculating time derivatives of the time domain thermal characteristics and the frequency domain structural characteristics in real time in the process of executing the steps, and terminating the ageing test and outputting a qualification judgment when absolute values of the time domain thermal characteristics are lower than a preset convergence threshold. According to the invention, the time domain thermal characteristics and the frequency domain structural characteristics are obtained simultaneously through the composite excitation signals, and decoupling discrimination of thermal effects and structural aging is realized by utilizing the differential indexes. The grading modulation strategy based on the differentiation index can adaptively adjust the test parameters according to the actual state of the tested sample, reduces the stress intensity when the thermal drift is dominant to avoid misjudgment, and enhances the stress intensity to accelerate the defect exposure when the structure aging is dominant, there