A Novel Miniaturized Tri-band VCO Utilizing a Three-mode Reconfigurable Inductor

A novel miniaturized tri-band complementary metal-oxide-semiconductor (CMOS) voltage-controlled oscillator (VCO) utilizing a three-mode reconfigurable inductor is proposed. The reconfigurable inductor consists of primary and secondary windings with a center loop connected to each winding center-tap to enable three-mode operation. By adjusting the diameter of each winding and loop, the equivalent inductance for each mode can be designed independently, resulting in a high degree of freedom for a tri-band VCO with minimal Q-factor degradation. The VCO implemented in a 28nm CMOS process shows frequency tuning ranges of 16.78–20.13GHz, 19.8–24.15GHz, and 33–41.13GHz for each mode with corresponding phase noise and tuning range figure-of-merit (FoMT) values of −190.1, −190.9, −194.6dBc/Hz. The fabricated chip consumes 12.72mW and occupies a core area of 0.043mm
²
.