Low-power LC VCO Research Articles

A low-power 2.4-GHz combined LNA–VCO structure in 0.13-µm CMOS

A combined low-noise amplifier and voltage-controlled oscillator (LNA---VCO) is implemented in a 0.13-µm CMOS technology. The low-power LC VCO and LNA circuits are stacked and share the same bias c...

A 900 MHz low power LC-VCO with improved phase noise performance

In this paper, we present the design and development of a low-power LC-VCO with improved phase noise performance by implementing a new capacitor divider varactor configuration and a 2nd order notch filter. We propose a new time-weighted approach to model the effective capacitance experienced by the oscillating signal over the oscillation period. The modeled effective capacitance is used in the calculation of the oscillation frequency, which agrees well with the simulation results. Two VCOs are designed and fabricated in TSMC 0.18 μm technology. The oscillation frequency is tunable from 759 to 910 MHz with a tuning range of 18%. At 900 MHz carrier, the measured phase noise is ?126.1 dBc/Hz at 1 MHz frequency offset with 4.5 mW power consumption.