A Novel All-Digital on-Chip Aging Sensor Robust to Process Variations

With the development of semiconductor technology, the reliability of integrated circuit (IC) is challenged by multiple aging mechanisms, which could increase the delay of ICs and cause timing violations. Hence, it is necessary to monitor the aging degree of the IC in real time. In this paper, we present a novel on-chip aging sensor based on path delay measurement, which can perform accurate measurement in two clock cycles. The proposed sensor is all-digital with low area overhead. Experiment result shows that the random measurement error is less than 2.92ps during 2 years aging. In addition, the sensor is robust to process variations.