Scan insertion criteria for low design impact

Abstract

The paper focuses an the constraints that the new silicon technologies impose on the implementation of partial and full scan approach. In particular the ordering of Flip-Flops inside each scan chain must be decided taking into account the capacitance constraints imposed by new technologies. The main goal of this paper is to prove that recent technologies impose a new design flow, exploiting layout information for scan chain reordering. Two algorithms are then described, which reduce both the average and the maximum distance between FFs in the chains, thus reducing the power dissipation of the circuit, too. Preliminary results, obtained through the implementation of the algorithms in the Italtel Design Environment and their application on a sample circuit, are reported.