2.4-GHz band ultra-low-voltage LC-VCO IC in 180-nm CMOS

An ultra-low-voltage low phase noise LC-VCO IC has been demonstrated using 180-nm CMOS technology. The LC-VCO IC includes a cross-coupled pMOSFET pair, a symmetric three-port spiral inductor, MOS varactors and buffer amplifiers. The LC-VCO IC is designed, fabricated and fully tested on wafer. The VCO IC exhibits a phase noise of -118.9 dBc/Hz at 1 MHz offset from the 2.29 GHz carrier at a supply voltage of only 0.5 V. Moreover, minimum operation voltage of only 0.25 V has been achieved.