基于性能退化的电子产品筛选试验设计

Screening Test Design for Electronics Based on Performance Degradation

长寿命的电子产品在进行传统环境应力筛选试验时,为了剔除存在早期失效或缺陷的产品,需要将产品长时间置于应力环境下,然而这会对其中的合格品产生较大的老化影响.对于很多电子产品来说,失效是根据性能特征逐渐退化到某个临界值来判定的.为了缩短筛选试验时间,减少筛选应力对产品的老化影响,针对退化型失效产品,本文分析了退化正常产品和退化不正常产品的差异,假设待筛选产品的退化特征量分布为污染分布模型,并给出了一种筛选试验设计方法,利用污染分布的可识别性条件,结合对退化试验的分析确定模型系数,再基于退化数据的可靠性预测方法,确定筛选试验时间和筛选阀值.最后通过实例验证该试验设计的可行性.

Long-life electronic products need to be put in stress environment for long durations in order that items with infant mortality or defects are weeded out from the products. However, long stress durations cause aging effects on good items. For some products,failures are defined in terms of performance characteristics degrading some critical values.For reducing durations and aging effects,this paper analyzes the difference between normally and abnormally degraded products, assumes the distribution of product degradation characteristic variable is contaminated distribution model, and presents a degradation screening test design. This design firstly ascertains the model coefficient using identifiable condition of contaminated distribution combined with the analysis of degra- dation test,and then ascertains screening duration and screening critical value. Lastly, this paper gives an example to illustrate the feasibility of the design.