A 52.3-to-67.3GHz 35.8-kHz-Resolution Triple-Push DCO Exploiting Source-Combining Technique for Third-Harmonic Enhancement Achieving 196.4dBc/Hz Peak FoMT at 10MHz Offset

This paper presents a millimeter-wave (mm-Wave) triple-push digital-controlled oscillator (DCO). The 3rd-harmonic current is boosted by combining the 6-phase outputs through the source nodes of Gm transistors, resulting in high output power and inherent 1st-/2nd-harmonic spurs rejection. The off-resonance oscillation problem of the triple-push structure is eliminated by coupling the auxiliary transconductance cell. A high frequency resolution is achieved by using the phase tuning technique. The DCO in 65nm CMOS occupies 0.095mm² and exhibits a best-in-class FoMT at 10MHz offset of 194 to 196.4dBc/Hz from 52.3 to 67.3GHz with a 35.8kHz frequency resolution.