Design for sequential testability: an internal state reseeding approach for 100 % fault coverage

Abstract

This paper proposes a method to select observation points and flip-flops for partial reset. The method does not target minimum DFT insertion but a maximum improvement on testability. The proposed non-scan approach allows a at-speed testing. Experimental results show that the method achieves 100% fault coverage and 100% fault efficiency for benchmark circuits while requiring less ATPG effort (CPU time) with no scan necessity.