Efficient seed utilization for reseeding based compression [logic testing]

The conventional LFSR reseeding technique for test data compression generates one test pattern from each LFSR seed. The seed size is determined by the maximum number of specified bits in a test pattern belonging to a given test set. However, for most practical designs the majority of test patterns have significantly fewer specified bits compared to the maximum. This limits the amount of compression that can be achieved with conventional reseeding. This paper presents a new reseeding technique that overcomes this problem by generating a single test pattern from multiple seeds and multiple test patterns from a single seed. The new reseeding technique is applied to two industrial designs, resulting in significant reduction in tester memory requirement and test application time compared to the conventional reseeding technique.

用于测试数据压缩的常规LFSR回收技术从每个LFSR种子产生一种测试模式。种子大小取决于属于给定测试集的测试模式中指定位的最大数量。但是，对于大多数实际设计，与最大值相比，大多数测试模式的指定位明显少得多。这限制了通过常规恢复可以实现的压缩量。本文提出了一种新的播种技术，该技术通过从多种种子中生成单个测试模式和多种测试模式来克服此问题。新的播种技术应用于两种工业设计，与传统的恢复技术相比，测试器内存的需求和测试时间时间大大减少。