A low phasenoise, differentially tuned, 1.8GHz power VCO with an ESD-compatible 14dBm output stage in standard digital CMOS

This works presents the co-integration of a fully integrated VCO with an output stage in standard CMOS to be used in Δ-Σ-modulators. Special care was invested to respect the reliability, life-time and ESD-specifications of the 0.25µm process. Maximal measured output power is 14dBm at 50Ω load. The circuit set consumes only 22.7mW to reach 0dBm of RF output power. Through the combination of NMOS- and PMOS-varactors, the power VCO is differentially tuned from 1.62GHz to 1.85GHz. With a measured worst-case phasenoise of -119dBc/Hz@600kHz, the VCO fulfills DCS1800 phasenoise-requirements.