A wideband low phase noise LC-VCO using output enhancement technique in 130 nm CMOS Technology

We present in this paper two LC Voltage Controlled Oscillator (VCO) with an output enhancement technique to achieve better phase noise performance, which is the most critical parameter in VCOs. The two VCOs were designed with TSMC 130 nm CMOS RF Technology. The two VCOs use IMOS varactor configuration. The first VCO with Low Power (LP-VCO) operates at 1.6 GHz with 200 MHz frequency tuning range, the VCO core consume only 725 μW from 1.2 V supply, this VCO achieves a phase noise of -123.2 dBc/Hz and a Figure-of-Merit (FoM) of -185 dBc/Hz at 1 MHz frequency offset. The second VCO was designed to have wide tuning range frequency and low phase noise (WB-VCO). The latter operates from 3.28 GHz to 4.4 GHz and consume 6.7 mW from 1.2 V supply. The WB-VCO design achieves a phase noise of -133 dBc/Hz and -123.4 dBc/Hz at 1 MHz offset from 4.4 GHz and 3.28 GHz carriers, respectively. The calculated FoM and FoM
_T
at 1 MHz offset from 3.28 GHz carrier, are -195 and -204 dBc/Hz, respectively.