Optimal reconfiguration functions for column or data-bit built-in self-repair

In modern SoCs, embedded memories occupy the largest part of the chip area and include an even larger amount of active devices. As memories are designed very tightly to the limits of the technology, they are more prone to failures than logic. Thus, memories concentrate the large majority of defects and affect circuit yield dramatically. Hence, built-in self-repair is gaining importance. This work presents optimal reconfiguration functions for memory built-in self-repair on the data-bit level. We also present a dynamic repair scheme that allows a reduction of the size of the repairable units. The combination of these schemes allows repairing multiple faults affecting both regular and spare units, by means of low hardware cost. The scheme uses a single test pass, resulting on low test and repair time.