Application of asymmetrical periodic signals as test vectors for analog fault detection: a novel perspective of classical concepts

摘要

Analog fault diagnosis is a field of paramount importance,and test signal generation is an important prerequisite for analogfault detection. Several stimuli have been used as input testvectors. This study presents a novel approach for the adoption ofclassical methods and signals for fault detection. This involves theuse of asymmetrical periodic signals and comparison of theireffectivity in maximizing output response between faulty andconforming circuits. The technique helps to determine a minimal setof test signals for a circuit. It also enables the test designer toidentify the parts of the frequency spectra of various signal typesthat can pose problems of fault masking and fault dominance. Inaddition, the technique indicates certain sets of components formingambiguity groups, which exhibit complementary fault-masking effects.The method does not require access to internal nodes of the circuit.It only requires generation of standard asymmetrical signals and hencecan be implemented with the use of commonly available functiongenerators. The technique is applicable to integrated circuits andprinted circuit boards, as well as analog subsystems. It can also beapplied for fault isolation. The results include responses fromrepresentative benchmark analog circuits.