A $\mathbf{0.06}\mathbf{mm}^{\mathbf{2}}$ 27.5-to-30GHz Series Resonance VCO with Magnetic Mutual Resistance Achieving 207.2dBc/Hz $\mathbf{FoM}_{\mathbf{A}}$ at 10MHz Offset

This paper proposes a series resonance voltage-controlled oscillator (SR-VCO) with magnetic mutual resistance (MMR) for the mm-wave band. The SR-VCO utilizes a single transformer to implement the LC tank. By manipulating the phase shift of current flow in the primary and secondary coils of the transformer, two resistive impedances, referred to as MMR, are generated. MMR enhances the tank impedance, resulting in reduced power consumption. Since MMR arises from magnetic coupling and does not dissipate energy, it preserves the quality factor <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(Q)$</tex> of the LC tank while suppressing MOSFET-induced noise, which is a dominant contributor to phase noise at mm-wave frequency. The proposed SR-VCO is fabricated in a 65nm CMOS process. The measured phase noise (PN) is -120.1dBc/Hz at 1MHz offset, with a power consumption of 46mW. The prototype occupies <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$0.06\text{mm}^{2}$</tex> and achieves a <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{FoM}_{\mathrm{A}}$</tex> of 207.2dBc/Hz at 10MHz offset.