Optimized BIST Strategies for Programmable Data Paths Based on Cellular Automata
J. vanSas, Francky Catthoor, H.J. DeMan · 2005
In this paper, optimized test methodologies will be presented for the generation of a set of predetermined test vectors on chip to be used as part of a BIST strategy for complex programmable data paths. For this purpose, use has been made of a cellular automaton. CAST-2 accomplishes the synthesis of the cellular automaton and the self-test control logic, and evaluates the obtained cellular-automata based solution. Dedicated test strategies for one-pattern tests on the one hand and one- and two-pattern tests on the other hand have been developed. These optimized techniques guarantee a BET implementation with 100 % stuck-at and stuck-open/close fault coverage for all detectable faults. The method has been applied to the data paths of an industrial-size speech processing application, developed with the silicon compiler CATHEDRAL-11. The total data path self-test overhead in terms of area is economically acceptable in practice.