Fully integrated low phase noise multi-band LC-tank voltage controlled oscillator with switched-capacitor resonator

摘要

This paper presents the design and implementation of a fully integrated low noise multi-band LC-tank voltage-controlled-oscillator(VCO).Multi-band operation is achieved by using switched-capacitor resonator.Additional three-bit binary weighted capacitor array is also used to extend frequency tuning range in each band.To lower phase noise,two noise filters are added and a linear varactor is adopted.Implemented in a 0.18 μm complementary-metal-oxide-semiconductor(CMOS) process,the VCO achieves a frequency tuning range covering 2.26～2.48 GHz,2.48～2.78 GHz,2.94～3.38 GHz,and 3.45～4.23 GHz while occupies a chip area of 0.52 mm2.With a 1.8 V power supply,it draws a current of 10.9 mA,10.6 mA,8.8 mA,and 6.2 mA from the lowest band to the highest band respectively.The measured phase noise is-109～-120 dBc/Hz and-121～-131 dBc/Hz at a 1 MHz and 2.5 MHz offset from the carrier,respectively.