A low-power K-band Colpitts VCO with 30% tuning range in a 130 nm SiGe BiCMOS technology

This paper presents the design of an wideband voltage controlled oscillator (VCO) in K-band frequencies fabricated in a 0.13 pm SiGe BiCMOS process. The core of the VCO is built upon differential Colpitts topology and a differential common-base buffer stage isolates the core from the load. The VCO demonstrates a tuning range of 30.2 % covering from 22.77 GHz to 30.86 GHz. The VCO exhibits a minimum differential output power of -1.8 dBm and a maximum phase noise of -99dBc/Hz at 1 MHz offset. The chip has an area of 0.75 mm2and it consumes 45 mW power. The corresponding figures of merit at 1 MHz offset with and without the tuning range are -182 dBc/Hz and -172 dBc/Hz, respectively. Along with a frequency synthesizer and a multiplier, this VCO is a useful building block to generate wide-range of mm-wave signals for diverse applications.