A 1-V 5 GHz low phase noise LC-VCO using voltage-dividing and bias-level shifting technique

In this paper, we present a 1 V 5.2 GHz VCO using voltage-dividing and bias-level shifting technique to prevent loaded Q-factor degradation and increase oscillation amplitude. The proposed VCO achieves a phase noise of 115.5 dBc/Hz at 1 MHz offset from a 5.2 GHz carrier frequency with 3 mA bias current from 1.0 V power supply. Tuning range is 450 MHz by changing the control bias from 0 V to 1.0 V.