MarchGen: A March Sequence Generation Method for Faults With an Arbitrary Number of Operations in RAMs

Abstract

The March test is a widely applied test method for memory arrays. Nowadays, the advanced memory technologies keep introducing new types of defects, which bring diverse multioperation fault models in turn. The automatic March sequence generation methods are preferred to avoid the inefficient manual design. Most previous methods generate the March sequences that cover limited types of faults and strongly depend on the specific characteristics of known faults. To address this issue, this work proposes MarchGen, a March sequence generation method for memory faults with an arbitrary number of operations. First, the fault hierarchies, reduced taxonomy, and generic test conditions of 2-composite faults are analyzed. Then, the heuristic March sequence generation workflow is designed accordingly, which takes either fault models or test sequences (TSs) as input. Three optimization strategies are utilized to improve the fault coverage of the generated March sequences and the generation time consumption. The evaluation results show that the proposed method has low dependence on fault types. The generated March sequences reach 100% fault coverage for any simple and 2-composite faults or TSs, and the generation time is roughly linear with the size of the input set.