一种压缩向量对测试集的新方法

通过施加一个测试向量对，瞬态电流测试可以检测出CMOS数字电路中的某些故障，这些故障通常（例如开路故障）不能被传统的电压测试和稳态电流测试有效地检测出来。研究如何有效地压缩向量对测试集与通常的测试向量压缩一样，意义十分重要，但目前人们对此研究得较少。首先使用三种现有的游程编码方法对向量对测试集进行压缩，并比较它们的压缩结果。在此基础上．提出了一种更好的压缩方法。采用新方法对几个ISCAS标准电路的开路故障向量对测试集进行压缩，实验证明压缩效果比三种游程编码方法都要好。而且，新方法的解码代价非常小，适合压缩大型电路的开路故障测试集。

A New Method for Compressing the Set of Pairs of Test Vectors

IDDT testing can detect some certain faults in CMOS digital circuits by applying a pair of test vectors, in most cases, these faults (such as stuck-open fault) can not be detected efficiently by traditional voltage testing and IDDQ testing. Obviously, it is significant to find out effective ways to compress the set of pairs of test vectors, as well as conventional test vectors compression. However, few researches have been made until now. Three existed run-length coding methods are used to compact test set at first, and then compare their results of compression are compared, based on which a better compression method is proposed. Applying this new method to several test sets that can detect stuck-open faults in ISCAS benchmark circuits, the results are obtained that indicated that the new method works better than the above three run-length code methods. Moreover, the decoding cost of the new method is tiny which means this new method is suitable for compressing stuck-open fault sets in large-scale circuits.