An Adaptive Body-Biased VCO with Voltage-Boosted Switched Tuning in 0.5-V Supply

This paper presents an adaptive body-biased low-voltage VCO. Despite the 0.5-V supply, the VCO uses coarse digital tuning by employing voltage-boosting technique. In addition, the effect of PVT variations is reduced by adaptive body-biasing technique. The proposed VCO is implemented in 0.18 mum CMOS technology and operates at 2.4 GHz. It achieves phase noise of -115.8 dBc/Hz at 1-MHz offset and 7.3 % of tuning range, while consuming 200 muW. Figure-of-merit with the tuning range is -189.1 dBc/Hz, which is the lowest among the recent state-of-the-art low-voltage VCOs