A 25MHz–6.44GHz LC-VCO using a 5-port inductor for multi-band frequency generation

This paper proposes a wide tuning range VCO for multi-band frequency generation. The wide band oscillator consists of a dual-mode LC-VCO using a 5-port inductor, and a divider chain. The proposed 5-port inductor provides two different inductances, which could support two resonances in a compact chip area. Thus, for LC-VCO, two operation modes are obtained to increase the tuning range. The experimental results achieve 25MHz-to-6.44GHz of continuous tuning range with a FoM
_T
of -209 dBc/Hz.