Low Power Shift and Capture through ATPG-Configured Embedded Enable Capture Bits

Abstract

Excessive test power can cause multiple issues at manufacturing as well as during field test. To reduce both shift and capture power during test, we propose a DFT-based approach where we split the scan chains into segments and use extra control bits inserted between the segments to determine whether a particular segment will capture. A significant advantage of this approach is that a standard ATPG tool is capable of automatically generating the appropriate values for the control bits in the test patterns. This is true not only for stuck-at fault test sets, but for Launch-off-Capture (LOC) transition tests as well. It eliminates the need for expensive post processing or modification of the ATPG tool. Up to 37% power reduction can be achieved for a stuck-at test set while up to 35% reduction can be achieved for a transition test set for the circuits studied.