Initialization of Sequential Circuits and its Application to ATPG

Abstract

A general method for determining whether a certain design is initializable, and for generating its initialization sequence, is presented in this paper. This method is based on structural decomposition of the circuit, and can handle both logical (using X-value simulation) and functional initializability. The routines developed are then used for ATPG of sequential circuits. A "pre-test" sequence that initializes the good and as many of the faulty machines as possible is generated and used in conjunction with CRIS [5], a simulation based sequential ATPG program, to generate a test set for the circuit.