A Capture-Safety Checking Metric Based on Transition-Time-Relation for At-Speed Scan Testing

• Published in: IEICE Transactions on Information and Systems Vol. E96.D; no. 9; pp. 2003 - 2011
• Main Authors: KAJIHARA, Seiji, YAMATO, Yuta, FURUKAWA, Hiroshi, MIYASE, Kohei, ASO, Masao, WEN, Xiaoqing, SAKAI, Ryota
• Format: Journal Article
• Language: English
• Published: The Institute of Electronics, Information and Communication Engineers 2013
• Subjects: at-speed testing; ATPG; Circuits; Devices; Failure; IR-drop; low power test; Mathematical analysis; test power reduction; Time measurements; Vectors (mathematics)
• ISSN: 0916-8532; 1745-1361
• DOI: 10.1587/transinf.E96.D.2003

Test power has become a critical issue, especially for low-power devices with deeply optimized functional power profiles. Particularly, excessive capture power in at-speed scan testing may cause timing failures that result in test-induced yield loss. This has made capture-safety checking mandatory for test vectors. However, previous capture-safety checking metrics suffer from inadequate accuracy since they ignore the time relations among different transitions caused by a test vector in a circuit. This paper presents a novel metric called the Transition-Time-Relation-based (TTR) metric which takes transition time relations into consideration in capture-safety checking. Detailed analysis done on an industrial circuit has demonstrated the advantages of the TTR metric. Capture-safety checking with the TTR metric greatly improves the accuracy of test vector sign-off and low-capture-power test generation.