Designs of 16-to-24-GHz Inductor-Capacitor Digitally-Controlled Oscillators in 40-nm CMOS

In this paper, two LC-DCO designs with three-stage frequency tuning circuits in 40-nm CMOS technology are presented, and the post-layout simulations are performed. The first design is a small-area cross-coupling LC-DCO suitable for low-cost applications. Its frequency range is 15.56-24.57 GHz, and the average power is 7.1 mW. When the output frequency is 24.57 GHz, the phase noise is –101.47 dBc/Hz at 1-MHz offset, and the FoM is –180.8 dBc/Hz. The second design is a low-power complementary differential LC-DCO suitable for low-power applications. Its frequency range is 15.7-23.0 GHz, and the average power is 1.76 mW. When the output frequency is 23 GHz, the phase noise is –102.12 dBc/Hz at 1-MHz offset, and the FoM is –186.9 dBc/Hz.