A Low Voltage and Power $LC$ VCO Implemented With Dynamic Threshold Voltage MOSFETS

A 1.1-GHz voltage control oscillator (VCO) using a standard 0.18-mum CMOS 1P6M process is fabricated. The VCO was designed with dynamic threshold voltage metal-oxide-semiconductor field-effect transistors and extremely-low-voltage and low power operation is achieved using on-chip transformers in positive feedback loops to swing the output signals above the supply and below the ground potential. This dual-swing capability maximizes the carrier power and achieves low-voltage performance. This VCO prototype is designed for a 0.34-V supply voltage while the output phase noise is -121.2dBc/Hz at 1-MHz offset frequency at the carrier frequency of 1.14GHz, the figure of merit is -192.0dB. The total power consumption is 103.7muW with the 0.34-V supply voltage. Tuning range is from 1.06 to 1.14GHz about 80MHz while the control voltage was tuned from 0 to 1.8V. The die area is 0.625times0.79mm²