A low phase noise 0.9 / 1.8 GHz dual-band LC VCO in 0.18 μm CMOS technology

Abstract

This paper presents a low phase noise dual-band LC voltage controlled oscillator (VCO) in 0.18 ßm CMOS technology. The proposed CMOS LC VCO is realized employing varactor diodes, a switched capacitor array and a switched differential inductor, which operates the dual-band operation. The CMOS LC VCO is also implemented with low phase noise performance using two series inductors at common source nodes. The measured phase noises at 0.9 GHz and 1.8 GHz frequency bands are −135 dBc/Hz and − 126 dBc/Hz at 1 MHz offset. The chip size is 1.3×1.4 mm2, including pads.