Dynamic forward body bias enhanced tri-mode MTCMOS

Abstract

Ground bouncing noise produced during reactivation events is an exacerbating challenge to maintain accurate logic levels in Multi-threshold CMOS (MTCMOS) circuits. A new noise-aware MTCMOS circuit with dynamic forward body bias is explored in this paper to minimize the ground bouncing noise with smaller sleep transistors. The dynamic-forward-body-biased MTCMOS circuit lowers the peak ground bouncing noise by up to 27.76% while reducing the size of the additional sleep transistor by 85.71% as compared to the previously published noise-aware MTCMOS techniques with standard zero-body-biased high threshold voltage sleep transistors. Furthermore, the proposed forward body bias circuit technique achieves up to 14.67% noise reduction and 70% sleep transistor downsizing as compared to a previously published forward-body-biased tri-mode MTCMOS circuit technique. The design tradeoffs between ground bouncing noise and leakage power consumption are evaluated for various MTCMOS circuits in a UMC 80nm CMOS technology.