A 54-GHz push-push VCO with wide tuning range in 0.18-μm CMOS technology

The design of a V-band 54-GHz push-push voltagecontrolled oscillator (VCO) with a wide tuning range is presented in this article. The circuit is fabricated using 0.18-μm CMOS technology. A new single-turn inductor structure with a smaller inductance, which can reduce the substrate loss, is adopted for the oscillator core to have the performances of low phase noise and a wide tuning range. Besides, a new technique that delivers the output signal from the common drain of the two-stage buffers has been proposed to enhance the output power. The VCO core dissipates 8.54 mW from a 2 V supply. The buffer stage consumes 10.11 mW for raising the measured output power level up to -25 dBm. The measured output phase noise at an offset of 1 MHz from the carrier frequency of 53.0 GHz is about -94.45 dBc/Hz. This VCO, with a tuning range of 2.68 GHz (4.9%), shows the tuning-related figure-of-merit FOM_T of -170.12 dB.