Abstract
Power dissipation and delay fault coverage have always been a trade-off that becomes an actual issue for at-speed test scheme. In this paper, we list the sources of power dissipation and delay fault models that may affect circuits. After, we propose a comparison between two different at- speed scan testing schemes, namely Launch-Off-Shift (LOS) and Launch-Off-Capture (LOC). For this purpose, we operate a formal characterization of the two scan test schemes through their application in benchmark circuits.