A COMPACT SIZE LOW POWER AND WIDE TUNING RANGE VCO USING DUAL-TUNING LC TANKS

A novel 12 GHz VCO designed and fabricated in a 0.18 µm SiGe BiCMOS technology is presented. Strongly magnetic coupled dual LC tanks with fixed and tunable capacitive elements are introduced to extend tuning range and improve phase noise. By hybrid using of varactor tuning, loaded transformer tuning and switched capacitor tuning, the proposed VCO achieves a wide tuning range of 4.3 GHz (36%) and output power of -9dBm with only 4.5 mW power consumption and only 0.17 [mm.sup.2] chip area.