Multifrequency testability analysis for analog circuits

Testability analysis in analog circuits is an important task and a desirable approach for producing testable complex systems. In past years, most of the testability evaluation methods presented were based on measures of the degree of solvability of the fault diagnosis equations. In this paper, we study the testability of analog circuits in the frequency domain by introducing the analog fault observability concept. The proposed algorithm indicates the set of adequate test frequencies and test nodes to increase fault observability. We analyze the case of single fault and of double and multiple faults. Concepts such as fault masking, fault dominance, fault equivalence and non observable fault in analog circuits are defined and then used to evaluate testability. Finally, some experimental results are provided