-Band Class-B VCO in 22 nm FD-SOI With Inductive Source Degeneration of the Tail Current Source

Abstract

In this work, a voltage-controlled oscillator (VCO) in the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$K$ </tex-math></inline-formula> -band has been introduced that uses the proposed technique named “inductive source degeneration of the tail current source.” The contribution of this work is that the auxiliary resonator is placed differently than the conventional works so that it leads to a more compact solution without affecting the phase noise (PN). Based on the simulation results, for the same device sizes and power consumption, the proposed Class-B method reduces the PN by 1.5 dB than the conventional one at 1 MHz offset from 24 GHz center frequency. VCO has been fabricated on a die area of 0.026 mm2 in the 22 nm fully depleted silicon on insulator (FD-SOI) technology. The measurement was done in the free-running mode, and the results show a PN of −122.4 dBc/Hz at 10 MHz offset from the center frequency of 23.8 GHz. The power consumption of the VCO core is 14.4 mW with 1 V supply voltage. According to the measurement results, this work achieves <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\text {FoM}_{A}}$ </tex-math></inline-formula> , a figure of merit which considers the VCO core area, of −194.2 dBc/Hz at 10 MHz offset from the center frequency, featuring state-of-the-art among the CMOS VCOs in the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$K$ </tex-math></inline-formula> -band.