Issue No.03 - May-June (2008 vol.25)
Ruifeng Guo , Mentor Graphics
Yu Huang , Mentor Graphics
James Chien-Mo Li , National Taiwan University
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/MDT.2008.83
Scan-based testing has proven to be a cost-effective method for achieving good test coverage in digital circuits. The Achilles heel in the application of scan-based testing is the integrity of the scan chains. From 10% to 30% of all defects cause scan chains to fail, and chain failures account for almost 50% of chip failures. Therefore, scan chain failure diagnosis is important for effective scan-based testing. Chain patterns alone are sufficient to determine the fault type, but they are insufficient to pinpoint the index of a failing flip-flop. This is the fundamental motivation for chain failure diagnosis, which is the process of identifying one or multiple defective scan cells in a scan chain or defective scan-enable or clock signals. This article surveys chain fault diagnosis techniques. The authors classify these techniques into three categories: tester based, hardware based, and software based.
scan chain, chain diagnosis, survey, chain pattern, scan pattern, chain failure
Ruifeng Guo, Yu Huang, James Chien-Mo Li, "Survey of Scan Chain Diagnosis", IEEE Design & Test of Computers, vol.25, no. 3, pp. 240-248, May-June 2008, doi:10.1109/MDT.2008.83