Totally Self Checking reconfigurable duplication system with separate internal fault indication

A Totally Self Checking (TSC) reconfigurable duplication system with respect to single cell fault model is described in this paper. It consists of two identical functional self checking units that receive the same inputs. TSC checkers are associated with each functional unit and produce either a normal indication when the output is correct or an error indication when the output is incorrect. The circuit that receives the indications of the two TSC checkers is a TSC decision circuit that produces two indication outputs E and F, respectively. E indicates mainly the status of the outputs of units while F indicates the existence of internal faults in the TSC decision circuit. Such indications can be used for the non stop repair before redundancy is exhausted. Thus continuous operation is preserved increasing the availability and the reliability of the system