Electronic Design Automation

14.2. Fault Collapsing

Fault collapsing reduces the number of faults to be considered in fault simulation and ATPG so the overall run time can be reduced. Two requirements must be met for fault collapsing to become effective. First, fault collapsing must run much faster than fault simulation or ATPG; otherwise, fault collapsing may not be worth doing. Second, the collapsed faults must be representative of all original faults modeled in the circuit. In this section, we introduce two fault-collapsing techniques: equivalence fault collapsing and dominance fault collapsing. Linear time algorithms are given to meet the first requirement. We illustrate that dominance fault collapsing produces a fewer number of faults than equivalence fault collapsing. ...