A Millimeter Wave Class-F VCO with Third Harmonic Enhancement in 40nm CMOS

In this paper, the proposed millimeter-wave voltage controlled oscillator (VCO) is based on Class-F oscillator and adopts the design of multi-peak transformer to enhance the third harmonic so as to obtain higher frequency and lower phase noise. A high frequency millimeter wave VCO is realized by the design of a low frequency resonator. As a result, the VCO has lower phase noise and lower power consumption while obtaining wider frequency tuning range than traditional mm-Wave VCOs. In addition, a broadband buffer with a low-k
_m
transformer which can suppress the first-harmonic and extract the third-harmonic is proposed. Simulated results show that the proposed VCO exhibits phase noise of -93.6~-95.1dBc/Hz at 1 MHz offset at 72.8~90.1 GHz, and the DC power consumption of the VCO core is only 10.8mW at the supply voltage of 0.9V.