Differential output, transformer coupled push-push VCO and divider for 60GHz applications in 90nm CMOS

A push-push VCO with embedded balun and resistive CML divider for 60 GHz heterodyne transceiver architecture, are presented. The measured VCO second harmonic output frequency is ~44.6-50[GHz], i.e. ~11.4% tuning range. The phase noise at 1[MHz] offset from the carrier, is ranging between -109 to -112[dBc/Hz] and -97 to -100 [dBc/Hz], for f0/2 and 2 × f0 outputs, respectively. The circuit works from 1.3 V supply and consumes ~20mA current (VCO ~7 mA, Divider + Divider buffer~8 mA, second harmonic buffer ~3 mA). The output power is ~ -13 dBm and -20 dBm at the f 0/2 and 2 × f0 outputs, respectively.