Testing FPGA delay faults in the system environment is very different from "ordinary" delay fault testing

Explains differences between testing delay faults in FPGAs and testing delay faults in circuits whose combinational sections can be represented as gate networks. Formulates - in a form suitable for analysis of LUT-based FPGAs - conditions that allow one to check whether or not a given input pair is a test of specific type (non-robust, robust, etc.). The presented theoretical results are shown to simplify an analysis of the various methods for enhancing the effectiveness of detection of FPGA delay faults.