A 2.2-mW backgate coupled LC quadrature VCO with current reused structure

Abstract

This letter presents a backgate coupled quadrature voltage-controlled oscillator (QVCO) which consists of a pair of current reused LC-VCOs. The proposed QVCO is designed for 2-GHz operation based on a 0.18-mu m triple-well CMOS technology. Measurements show -102 and -124 dBc/Hz at 100-kHz and 1-MHz offset, respectively. Compared to the conventional QVCO, the proposed QVCO dissipates significantly lower power (1.74 mA from a 1.25-V supply) while showing good 1 / f(3) close-in phase noise.