A 0.7-V low-phase-noise multi-mode coupled class-B/class-C voltage-controlled oscillator for millimeter-wave applications

An ultra-low power dual-band multi-mode millimeter- wave voltage-controlled oscillator (VCO) with low phase noise is demonstrated. The proposed design includes switchable transformers to enhance the tuning range, a class-B and class-C coupled oscillator to achieve low phase noise, low power consumption, and quick start-up, and the push-push technique to achieve the W-band oscillation. Fabricated in 90-nm CMOS process, the measured phase noise at 10-MHz offset frequency is better than - 115.2 dBc/Hz for the frequency from 38.4 GHz to 46.5 GHz. The power consumption is 12mW under a 0.7-V supply. The FOM and FOM_T are -185 and -187.8 dBc/Hz, respectively. The pushpush oscillation frequency varies from 76.7 GHz to 93.2 GHz.