© 2015 Elsevier B.V. Negative Bias Temperature Instability (NBTI) is one of the major time-dependent degradation mechanisms that impact the reliability of advanced deeply scaled CMOS technologies. NBTI can cause workload-dependent shifts on a transistor's threshold voltage (VTH), and performance during its lifetime. This study presents a comparison of the NBTI aging on adder architectures and ring oscillators in the downscaling technology nodes. The first part of the study focuses on the NBTI-induced performance degradation of 32-bit adders (one of the most fundamental block of a processor's arithmetic logic unit) from the points of architectural topology and workload dependency in the planar technologies (i.e. commercial 28, 45, 65 nm node...