Dynamic NBTI Management Using a 45 nm Multi-Degradation Sensor

This paper proposes a low power unified oxide and negative bias temperature instability (NBTI) degradation sensor designed in 45 nm process node. The cell power consumption is 10⁵ lower than a previously proposed sensor. The unified nature enables efficient reliability monitoring with reduced sensor deployment effort and area overhead. Using the sensor dynamic NBTI management (DNM) has been implemented for the first time. DNM trades the excess “reliability margin” present in the design, due to better than worst case operating conditions, with performance. For the typical case shown in this paper, DNM allows for an average boost of 90 mV in accelerated supply voltage while bringing down the excess NBTI margin of 22.5 mV to 8 mV where the total budget for NBTI was 66 mV.