Summary: | 碩士 === 國立中正大學 === 資訊工程研究所 === 83 ===
Detection of system timing failures has become a very important problem as high speed system operation is required. Delay testing of a digital systems needs two test patterns to initialize a stable value on the fault site, and then propagate the fault effect to primary outputs. It has been demonstrated been demonstrateed that delay fault coverage loss could be significant, if improper propagation paths are used. This occurs when the delay test pair of a target propagation path can not be effectively generated by an ATPG tool, or studk - at test patterns are used as transition (or gate) delay test patterns. In this work, an efficient method is proposed to reduce the amount of fault coverage loss using multiple observation times. The basic idea is to offset the shorter propagation path (really used) by tightening the observztion time. Given a probability distribution of defect sizes and a set of slack differences, the method is able to loxate several observation times that result in small fault coverage loss.
|