A Low Phase Noise Dual-Core V-band VCO based on Class-B Structure

A voltage controlled oscillator (VCO) based on 65nm CMOS technology with center frequency of 62.5GHz is proposed for phase-locked loop module in transceiver. There is a current bias array in the VCO to meet the static operating point of the VCO negative resistor. The phase noise of the VCO is optimized by increasing the bias capacitance to filter out the chattered current. The tuning range of the tuning curve is improved by using two cores (high and low frequency bands are selected by switching on and off). The output buffer stage adopts common source stage circuit to reduce the influence of parasitic capacitance of output load. The VCO occupies an area of 0.52mm*0.28mm, the output power is −10 dBm, 1MHz offset phase noise is better than -87.89dBc/Hz, the coverage is 60~65GHz, and the 1.2V supply power is about 24mW.