Class-C Quadrature VCO with Ring-inductor Coupling and Folded-Cascode Mixer Design

This article investigates the quadrature voltage-controlled oscillator (QVCO) by using the loop closed-ring inductor and merging the excellent efficiency of class-C oscillator to the complementary PMOS-NMOS topology. Designed from TSMC 0.18 μm 1P6M CMOS processing, the presented folded-cascode mixer exhibits a high conversion gain, a maximum input P1dB of -12 to -16.7 dBm, IIP3 of -4.5 to -7.2 dBm, and LO to RF isolation of about 33.8 dB at VDD=1.5 V, respectively. The proposed QVCO works during 6.69 and 7 GHz at overall power dissipation is 7.59 mW. Experimental of phase noise and evaluated figure of merit (FOM) of the promoted 6.69 GHz QVCO are -113.56 dBc / Hz at 1 MHz frequency offset and -181.2 dBc/ Hz, respectively.