A1.3～2.2 GHz Low Phase-Noise Low-Power CMOS LC VCO

This paper presents a wide-band low phase-noise and low power voltage-controlled oscillator(VCO).To cover a frequency range of 1.3~2.2GHz and maintain extremely low gain,a bunch of 128 tuning curves realized by7-bit switching capacitor array is applied in VCO.On the other hand,wide-range leads to huge gain variation.To combat it,a 3-bit self-controlled varactor array is also proposed.Besides,to enlarge each tuning curve linear range,distributed biased varactor technique is still adopted.Fabricated in TSMC 0.18μm CMOS process,the tuning curve linear range is 0.2~1.6 V,and VCO can cover 1.3~2.17 GHz frequency.The overlap of high band adjacent curves is more than 50%,and low band is even more than 80%.The average gain is only 19 MHz/V,and the fluctuation range is 13~25MHz/V.For 1312 MHz,the VCO phase noise is-116.53dBc/Hz at 1MHz offset;while for 2 152 MHz,it is-112.78dBc/Hz.VCO consumes 1.2~3.2 mA for a 1.8 Vsupply voltage.The proposed VCO can achieve wide tuning range and low phase noise.It has been successfully integrated in the frequency synthesizer for Wireless networks for Industrial Automation(WIA)applications.