Frequency Scaling and Topology Comparison of Millimeter-wave CMOS VCOs

Abstract

This paper presents an algorithmic design methodology and frequency scaling technique for CMOS VCOs. It illustrates the almost ideal scaling of a fundamental 10-GHz, 90-nm CMOS Colpitts VCO with -117 dBc/Hz phase noise and 4 dBm output power to 77 GHz. The 77-GHz VCO features linear 8.3% tuning range and a phase noise of -100.3 dBc/Hz at 1 MHz offset. The first complementary cross-coupled VCO operating at 77 GHz is also reported. In addition, a new figure of merit for CMOS VCO based on the one defined in the 2003 ITRS is proposed to adequately account for the VCO output power and efficiency