A 0.6 V 10 GHz CMOS VCO Using a Negative-Gm Back-Gate Tuned Technique

Without an extra on-chip accumulation-mode MOS varactor, a voltage-controlled oscillator (VCO) using a negative-transconductance back-gate tuned technique is demonstrated in a standard 0.18 μm CMOS process to achieve low-voltage, wide-range and high-frequency designs. Employing the varied p-n junction capacitance and the varied transconductance in the intrinsic-tuned regime, the VCO provides the tuning range of 9.95 to 11.05 GHz at a 0.6 V supply and dissipates below 4.35 mW. At 11 GHz carrier frequency, the measured phase noise is -110.4 dBc/Hz at a 1 MHz offset.