Advancing Technology: Test-Based Failure Analysis – Part 2: Fault Diagnosis

This is the second article in a two-part series on test-based failure analysis (TBFA). The first article, which appeared in the August 2001 issue of EDFA, discussed the need for automated diagnostics and the general concept of TBFA. This article discusses the steps involved in implementing a TBFA process and addresses the challenges that are likely to be encountered. It explains how to gather data required to link observed behavior to specific faults, how to set up and use fault dictionaries, and how to handle unmodeled as well as bridging faults. It also discusses the use of TBFA with conventional voltage and quiescent current (IDDQ) testing.