Improve the quality of Faster Than At-Speed Testing using the statistics information

Abstract

Test generation method for the small delay defects not only requires low algorithm complexity, but also need more possibility to detect small delay. The method proposed in this paper uses statistical information to provide guidance for the back stage in test generation, which can improve test quality effectively. This method firstly uses simulation to obtain the statistical probability of nodes in the circuit, and then uses statistical information and controllability of nodes in circuit to determine the unknown conditions in advance in back stage, thereby reducing the number of backtrack and improving fault coverage. The result of testing on ISCAS'89 benchmark circuits shows that the test generation based on probability statistics method can make the transition delay fault coverage increase about 1.3% and time save about 9%. Keyword;small delay defects; faster than at-speed testing;probability statistics; path sensitize