Hierarchical test generation for combinational circuits with real defects coverage

This paper deals with the automatic test pattern generation (ATPG) technique at the higher level using a functional fault model and defect-fault relationship in the form of a defect coverage table at the lower level. The paper contributes to test pattern generation (TPG) techniques taking into account physical defect localisation. A new parameter––probabilistic effectiveness of input patterns––has been used in the TPG technique with the goal of increasing real defect coverage. This parameter is based on probabilities of physical defects in digital cells which may occur in real integrated circuits. This improvement has been implemented into the existing DefGen ATPG system for combinational circuits. 2002 Elsevier Science Ltd. All rights reserved.