Scan-chain masking technique for low power circuit testing

This paper addresses the issue of blocking pattern selection to reduce both leakage and dynamic power consumption during circuit testing using scan-based approach. The blocking pattern is used to prevent the scan-chain transitions to reach circuit inputs. This, though reduce dynamic power significantly; can result in quite an increase in the leakage power. We have presented a novel approach to select a blocking pattern using genetic algorithm and use it properly so that both dynamic and leakage power are reduced. The average improvement in dynamic power is 20.4% and for leakage power it is about 10.8% (best is around 97.0% and 22.8% respectively) with respect to full scan circuit.