Adaptive algorithm for analog fault based on a sensitivity matrix and the fuzzy set theory

Recently, most on going research has been focused on distinguishing faulty or healthy circuits - from the manufacturer´s point of view, this is more important than locating particular faulty elements. A faulty circuit is returned to the design engineer and this person must consider the possibility of redesigning the schematics (if the problem occurs frequently). To find and locate faulty elements in a circuit, the sensitivity matrix can be used. It has been observed that for most practical circuits the sensitivity matrix is sparse. This observation has been utilized in fuzzy expert systems and system modifications based on the reduction of the sensitivity matrix size have been proposed. The modified system can effectively detect and locate single catastrophic faults as well as parametric ones. The first results obtained and presented here are promising, and tend to prove that the proposed strategy can improve fault detection and location rate.