A 34 GHz CMOS VCO with Transformer Tail-Node Filter and TSPC Frequency Divider in 22 nm FDSOI

This work proposes a compact, low-power CMOS voltage-controlled oscillator (VCO) with distributed transformer tail-node filter for phase noise reduction. The circuit is integrated into a 22nm fully-depleted silicon-on-insulator (FDSOI) technology, offering high-performance n- and p-MOS transistors. Using a combination of SOI varactors and switched capacitors, a wide tuning range of 22.8%, covering 30.4 to 38.24GHz, is reached while maintaining a phase noise below -97dBc/Hz at a 1MHz carrier offset. An area- and power-efficient true single-phase-clock (TSPC) frequency divider is implemented to ease the use of the VCO within a low-frequency PLL. The overall circuit consumes 9.4mW supplied from a 0.8V source and 170$\times$ 370 $\mu \mathrm{m}^{2}$ core area, including an output buffer and the divider. The circuit performance results in a corresponding FOM and FOM
T
of -178.3 and -185.3 dBc/Hz.