Automatic modification of sequential circuits for self-checking implementation

Cascade Scheme for Concurrent Errors Detection

“…The Berger code [2], and sometimes the Smith code [3] are used for detecting unidirectional faults. A number of algorithms are known [4,5,6,7], which allow converting an arbitrary scheme in such a manner that the Berger code could be used for its checking. To this end, the scheme can be modified in such a way, that only its input variables become negated [4].…”

“…The works [5,6] propose algorithms of converting the scheme under check by duplication of some of its elements. The paper [7] describes a combination of several approaches.…”

Multiple transient faults in logic: an issue for next generation ICs?

“…Afterwards, we will investigate the effectiveness of self checking circuits designed using AUED codes and the rules in [14,15,16]. The application of the developed tool to benchmark circuits has proven that, as expected, even though the use of such techniques can not solve the problem when we have to cope with multiple TFs, it allows a reduction of the probability to have bidirectional errors due to multiple TFs up to approximately the 40%.…”

“…Error detecting/correcting codes are widely used to protect them against this kind of errors [13]. Instead, to protect logic with respect to TFs, techniques based on self checking circuits (SCCs) and recovery are frequently employed [14,15,16]. Efficient error detecting codes frequently adopted for self-checking circuits are the All Unidirectional Error Detecting (AUED) ones [17,18], that is codes able to detect all errors whose erroneous bits are 1s rather than 0s, or vice versa, but not both, within the same codeword [18].…”

“…In Section 4, by means of our developed software tool, we evaluate the likelihood of bidirectional errors due to multiple TFs for some benchmark circuits. In Section 5, we investigate the effectiveness in reducing the number of bidirectional errors due to multiple TFs of the design techniques introduced in [14,15,16] for single TFs affecting self-checking circuits. Finally, in Section 6 we give some conclusive remarks.…”