Partial Scan Using Multi-Hop State Reachability Analysis

Sequential test generators fail to yield tests for some stuck-at-faults because they are unable to reach certain states necessary for exciting propagating these target faults. Adding scan to the circuit increases reachability of these hardto-reach and or previously unreachable states. In thispaper, we postulatedthat fewer scan ip- ops are needed to make these states reachable. The states necessary for detecting the hard-to-detect faults, when reached, will facilitate reachingother hard-to-reach states in one or more hops by the sequentialtest generator, resultingin signi cantly higher fault coverage. We collect information on the hard-to-reach, aborted, and easy states in our analysis. Results from our approach have indicated that higher fault coverage can be achieved withsigni cantlyfewer scan ip- opsforsomecircuits.

• Type: Conference
• Year: 1999
• Where: VTS
• Authors: Sameer Sharma, Michael S. Hsiao
• Keywords: Circuit Increases Reachability, Fewer Scan Ip, Hardware, Scan Ip, VTS 1999