Design and optimization of a low-noise cross-coupled fundamental VCO in 90nm CMOS for 60GHz applications

A methodology for the design and optimization of a low noise cross-coupled fundamental VCO for 60 GHz applications is presented in this paper. Using a parametric study, semi-empirical relations are derived for the oscillator elements, enabling optimization for phase noise, tuning range and power, The designed VCO is implemented in 90 nm standard CMOS technology, offers a frequency tuning range of 2.5 GHz around 58.7 GHz using a combination of analog control of AMOS varactors and a four-bit digital control bus of differential switched capacitance cells. The VCO yields a measured phase noise of -100 dBc/Hz at 1 MHz offset consuming 20 mW and -106 dBc/Hz consuming 55 mW.