19-GHz VCO with Phase Noise of -117 dBc/Hz at 1-MHz Offset Using an Array of Near Minimum Size Transistors and Intelligent Post Fabrication Selection

A 19-GHz voltage-controlled oscillator (VCO) implemented in a 22-nm FDSOI CMOS process, which uses an addressable array of cross-coupled near minimum size NMOS transistor pairs and post fabrication selection demonstrates phase noise (PN) of -117 dBc/Hz at 1-MHz offset frequency while dissipating 8 mW of DC power. The PN is more than 5 dB lower than that of CMOS VCO's operating at 15–20 GHz in the literature. This work also suggests that identification of combinations with lower PN using fewer measurements is possible by avoiding uses of the transistor pairs with high noise and demonstrates that the technique can be applied to circuits operating at ~20 GHz and utilized in an advanced CMOS node.