Knowledge-based debugging of ASICs: real case study and performance analysis

The authors report new developments of the IMAG-TIM3 laboratory´s project of automatic prototype validation of VLSI circuits by making joint use of internal probing using an electron-beam tester (EBT) and automatic fault localization using a second-generation knowledge-based system (KBS). They focus on the automatic fault localization methodology. The choice of a knowledge-based approach results from the fact that the aim of the prototype validation process is to localize residual design or prototyping faults. A real case study on a prototype of an A/D (analog-to-digital) converter is described, and the system performances are obtained. The analysis of these performances leads to the definition of some heuristics, in order to assist the design engineer in choosing the best debugging strategies according to the circuit features and complexity.<>