测试性框图模型比较研究与改进

Comparison and Improvement of Testability Schema Models

摘要:

对TEAMS和eXpress两款主流测试性建模与分析软件所采用的测试性框图模型——多信号模型和混合诊断模型,从产品结构单元表示、端口表示、功能(信号)表示、故障模式表示、测试表示等多个方面进行了深入比较研究,并对二者进行了综合评价;在此基础上,综合两者特性提出了一种新的测试性框图模型改进方案——端信号模型;通过将组元端口所通过信息流直接视作信号、引入结点、扩充信号映射定义、允许定义多值测试等多种设置,端信号模型方案能够支持基于电路网表创建模型和更为精确化的故障－测试关联性描述。

Abstract:

TEAMS and eXpress are two typical commercial softs for testability modeling and analysis. The model used in TEAMS is multi-signal model. The model used in eXpress is hybrid diagnostic model. These two models are all testability schema models. The article compares multi-signal model and hybrid diagnostic model in representation of product structure,port,function,failure mode,test,etc. Based on the comparison,a new testability schema model – port signal model is proposed. The info flows of ports are look as signals in port signal model. Signal mapping definition is extended,and multi-outcome test can be modeled in port signal model. So port signal model can be made from circuit netlist file automatically,also can describe the dependency of faults and tests more accurate.