模拟电路符号法可测度分析的改进

Improvement of Analog Circuit Testability Analysis Based on Symbolic Method

可测度是电路测试和故障诊断中一个重要概念,是测试节点选择的一个量化指标;使用符号分析的方法进行电路可测度计算;为了解决当诊断方程分母多项式的最高项系数不等于1时,符号法不能应用的问题,提出了一种原始诊断方程变换的新方法,利用符号法计算变换后诊断方程的可测度;电路实例分析表明,改进后的方法可以处理任意形式的电路诊断方程,计算中避免了误差的引入,具有计算简单、结果准确的特点。

Testability is an important concept in circuit test and fault diagnosis field, and it is a quantity measure of test node selection. Symbolic method is used to evaluate circuit testability. To resolve the problem that the symbolic method can＇t apply to the diagnosis equation whose coefficient of the item with highest power in the denominator is not equal to 1, a new method is proposed to transform the Original di- agnosis equation into a new one, which is then used to evaluate the circuit testability. The example circuit analysis shows that the improved method can do with any form fault diagnosis equation, it eliminates error introduction during calculation and has the feature of simple and ac curate.