Time slot specification based approach to analog fault diagnosis using built-in current sensors and test point insertion

Testing and diagnosis of analog circuits continues to be a hard task for test engineers and efficient test methodologies to tackle these problems are needed. This paper proposes a novel analog test method using time slot specification (TSS) based built-in current sensors. A technique for location of a fault site and fault type, based on TSS, is presented. The proposed built-in current sense and decision module (BSDM), in association with TSS analysis, has high testability and good fault coverage, and a capability to diagnose catastrophic faults and parametric faults in analog circuits. The digital output of the BSDM can be easily combined with built-in digital test modules for mixed-signal IC testing. The general heuristics for test point placement are also described.