Area overhead reduction for small-delay defect detection using on-chip delay measurement

Recently, on-chip delay measurement was proposed to detect small-delay defects. However, small-delay defect coverage of on-chip delay measurement method is very low. A conventional method has been proposed to improve the small-delay defect coverage. However, it leads to high area overhead. To reduce the area overhead, this study presents a method using LOS+LOC based on the conventional method. To achieve a more effective defect coverage with the same hardware overhead, we should set the area of observation point occupies 50~70% of the overall hardware overhead. The proposed procedure can provide similar or higher defect coverage with very small hardware overhead. Specifically, the hardware overhead is 9.27~35.21% smaller than the conventional method.