A low‐power technique to boost the output amplitude of multi gigahertz push‐push LC VCOS

A design technique to increase the output amplitude and hence the output power of push-push LC-based voltage-controlled oscillators (LC VCOs) is presented that relies on LC resonance boosting of the second harmonic. Measurement results are in good agreement with the results predicted from the analysis. Using the proposed technique, a low-power push-push LC VCO is designed and implemented in 90-nm CMOS. Based on the measurement results, the VCO has a frequency tuning range of 23%, from 20.1 to 24.8 GHz. It exhibits up to 8 dB improvement in its output power at the middle of the frequency band compared to a traditional push-push VCO. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1581–1584, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27599