On evaluating speed path detection of structural tests

The detection of speed-related defects relies on fault excitation and propagation along critical speed paths in the design. Different types of structural tests detect speed paths differently. In this paper, we compare the capabilities of speed path detection using Ndetect and timing-aware transition tests on silicon. Experimental data on the latest quad-core AMD Opteron¿ processor is collected. Results show either pattern set catches a significant amount of speed paths that is not predicted as critical timing paths. This illustrates the difficulty in pre-determine a subset of critical timing faults targeted for timing-aware transition test, while shows Ndetect transition test can be a practical solution for general speed path profiling.