A 2.0 GHz LC- VCO with 1.4 GHz Tuning Range and Switched Varactor Array

This work presents a complementary cross-coupled LC-VCO with Switched Varactor Array (SVA) and degeneration resistor core-based topology. The SV A application for discrete frequency control allows a tuning range enhancement with improved linearity and reduced number of switches for avoiding the losses in phase noise performance. From 4 prototypes with Vcc <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">=1.2V</tex> and current consumption IDC <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">=5.3mA</tex> , a phase noise PN <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">≈-127</tex> dBc/Hz@l MHz was obtained at F OUT <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$=1.9$</tex> GHz for a tuning range FTR <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">=89%(FOMT=₋204</tex> and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">FOML=₋218)</tex> . The schematic level design of the system was performed from Cadence environment by applying TSMC 65 nm CMOS technology.