Signal coding technique and CMOS gates for strongly fault-secure combinational functional blocks

This paper proposes a signal coding technique (using frequency redundancy) and CMOS gates to allow the design of functional blocks of self-checking circuits whose correct operation is guaranteed with respect to a wide set of possible, internal faults. These include not only conventional stuck-ats, but also transistor stuck-ons, transistor stuck-opens and resistive bridgings. Compared to the alternative, existing solution, the technique proposed here does not imply any critical constraint on the circuit electrical parameters. Hence it is better suited to the design of next generation, deep submicron technology circuits.