Self-checking monitor for NBTI due degradation

Abstract

Performance degradation of integrated circuits due to aging effects, such as Negative Bias Temperature Instability (NBTI), is becoming of great concern for current and future CMOS technology. In this paper we propose a monitor able to detect NBTI due late transitions in the combinational part of a critical data-path. It requires lower area than recently proposed alternative solutions, and a lower or comparable power consumption. Moreover, differently from alternative solutions, our monitor is also self-checking with respect to its possible internal faults, thus avoiding the useless negative impact on system performance and the negative impact on system reliability which could otherwise take place in case of non self-checking sensors, should they get affected by faults.