A 48 GHz 196 dB-FOM LC VCO With Double Cap-Degeneration Negative-Resistance Cell

This letter presents a 48-GHz capacitively emitter-degenerated LC voltage controlled oscillator (VCO) with double cross-coupled pair showing higher and lower input capacitance than typical cross-coupled pairs. The phase noise of the proposed LC VCO is measured as 114.5 dBc/Hz at 1 MHz offset from 48 GHz carrier, and a current of 6 mA is drawn in the VCO circuit. The proposed VCO shows an excellent figure of merit of 196 dB.