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A circuit topology suitable for a low-voltage low-power Colpitts voltage-controlled oscillator (VCO) is presented in this paper. By employing inductors for a negative-conductance boosted structure, the dc power consumption of the Colpitts VCO can be effectively reduced. Based on the proposed architecture, the VCO fabricated in 0.18-μm CMOS exhibits a measured 1.3% tuning range around 30 GHz. Operating at a supply voltage of 1.0 V, the VCO core consumes 2.3-mW dc power, and the measured phase noise is -104.1 dBc/Hz at 1-MHz offset. Compared to the recently published 20 to 30-GHz 0.18-μm CMOS VCOs, this work achieves a reduced supply voltage, minimized dc power consumption, small chip size, superior figure-of-merit (FOM), and better figure-of-merit including the tuning range (FOMT). Formulas for considering the nonlinear characteristics of varactors and active devices are also presented, and the accuracy of predicting the VCO tuning curve is validated by measurement.