Process variation tolerant online current monitor for robust systems

Large inter-die and intra-die process variations result in significant uncertainty in delay of circuits. Large delay variations may lead to parametric/functional failures. In this paper we propose a leakage-variation-tolerant online current monitor, namely leakage canceling current sensor, to detect completion of operations in logic blocks. The current monitor is applied to self timed logic to design process variation tolerant circuits. It is observed that, for self-timed circuits, the probability of functional failures can be reduced by 50% with no performance degradation and with same power consumption.