A Self cascoded body biasing technique for ultra-low-power sub-threshold ring oscillator

Abstract

The paper presents a low-power sub-threshold ring oscillator for self-powered IoT devices.Self cascoded body biasing technique is applied to each inverter in ring oscillator to enable low voltage operation. As a result, higher body biasing magnitudes are achieved compared to the conventional body biasing scheme. Furthermore, a significant reduction in subthreshold-leakage current accordingly reduces the power consumption. A three-stage ring oscillator circuit is designed for the desired oscillating frequency of 2.65 MHz. The proposed design has been implemented in standard CMOS 180 nm technology. Post-layout simulation results describe the proposed design takes low power consumption of 58.9 nW at the minimum supply voltage of 270 mV.