Impact of multiple input switching on delay test under process variation

Multiple input switching (MIS) on off-path inputs is known to increase the delay through a gate. However, due to the complexity of incorporating MIS in timing analysis, design flows typically ignore the effect of MIS. Test tools also do not attempt to maximize the off-path switching to maximize delays through a path. In this paper we study the impact of not maximizing the switching on the off-path inputs in different process corners. We present quantitative data to estimate the test escape or mis-binning that could result if MIS is not considered as part of our path-delay test generation process.