Novel Adaptive Body Biasing Techniques for Energy Efficient Subthreshold CMOS Circuits

Operating CMOS circuits in the subthreshold region reduces energy dissipation by orders of magnitude if compared to the strong inversion region, which makes it very suitable for moderate-performance applications that require ultra-low energy dissipation. In this paper we propose three new energy-efficient subthreshold CMOS circuits; the proposed techniques are based on the use of adaptive body biasing to control transistors' subthreshold currents. The proposed techniques can achieve 47% faster operation and have up to 77% Energy-Delay-Product (EDP) savings than the existing subthreshold circuit enhancement techniques in 0.18 m CMOS technology. Also the proposed techniques are shown to be more robust and stable against temperature variations, fan-out variations, and process parameters variations.