EARTH: combined state assignment of PLA-based FSM's targeting area and testability

Abstract

Stuck-at and crosspoint faults in PLA's introduce combinational and sequential redundancies in PLA-based FSM's that affect the testability of these FSM's. We propose a new state assignment algorithm for PLA-based FSM's called EARTH that simultaneously considers area minimization and testability of the resultant PLA's. Our fault model is the single stuck-at and/or single crosspoint fault model. Experimental results show that, on an average, the number of undetectable faults which result due to state assignment by EARTH is about five times less than those generated due to state assignment by NOVA with area overhead 2% more than NOVA.