On-line testing of transient faults affecting functional blocks of FCMOS, domino and FPGA-implemented self-checking circuits

In this paper we analyze the problems which may arise because of transient faults affecting the functional blocks of CMOS self-checking circuits. In particular, we consider the case of both combinational and sequential functional blocks implemented using FCMOS or domino circuits, as well as field-programmable gate-arrays (FPGAs). We will show that, in the case of FCMOS and FPGA implemented circuits, transient faults may result in output non-unidirectional errors that can not be detected by the error detecting codes that are generally used for self-checking circuits, thus requiring additional strategies to guarantee a self-checking behavior. Reversely, this is not the case for domino circuits, which can therefore be easily concurrently checked using conventional error detecting codes. Strategies possibly used for the case of FCMOS and FPGA implemented circuits are also discussed and applied to a set of benchmark circuits.