A swing-enhanced current-reuse class-C VCO with dynamic bias control circuits

Abstract

A swing-enhanced current-reuse class-C VCO which can theoretically achieve same phase noise figure-of-merit (FoM) as other class-C VCOs at the lowest power consumption is presented. A swing enhancement in class-C operation and an oscillation robustness are achieved through dynamic bias control circuits for both NMOS and PMOS transistors. The proposed VCO has been fabricated in 180nm CMOS process while oscillating at 4.6 GHz. The measured phase noise is -119 dBc/Hz at 1 MHz offset while consuming 1.6 mA from 1.5 V supply. An FoM of -189 dBc/Hz is achieved.