A 57∼66GHz CMOS voltage-controlled oscillator using tunable differential inductor

Short-range wireless data transmission around the 60GHz band has been flourishing for various biomedical applications due to its features of high speed, high security and small device size. Wireless monitoring of human body with such transceivers has enabled numerous research areas in healthcare and biomedical engineering, such as long-term real-time recording of the Electroencephalography signal while the subject is in real-life scenario. Among the design challenges of such transceiver, the voltage-controlled oscillator (VCO) design plays a key role. Large tuning range of the VCO enables the effective utilization of the spectrum while small area is desired for biomedical application with implantation. This paper proposes a novel circuit topology for 60GHz VCO. It covers the full unlicensed 57~66GHz frequency band and supports multi-band operation. Simulated in UMC 1P9M 65nm CMOS technology, a tuning range of 14% has been achieved with low power consumption. The VCO core only occupies an area of 60×80um², which is the smallest for 60-GHz applications published ever.