Millimeter wave CMOS VCO with a high impedance LC tank

The proposed VCO achieves low phase noise with high oscillation amplitude by using a high impedance resonator. This resonator has two resonances including the resonance of an additional inductance and a device output capacitance. The proposed VCO is implemented with a 0.13-µm CMOS process and the chip size without the pad is 150um × 250um. The VCO shows phase noise of −94.83dBc/Hz at 1MHz offset, −13.33dBm output power at 55.63GHz oscillation frequency, and the power dissipation of 8.25mW including that of the buffer. In order to provide a comparison with a VCO with a conventional resonator, two VCOs with different resonators are designed. The proposed VCO shows 7.5dB higher output power and 11dB lower phase noise than the VCO with a conventional resonator. The proposed VCO can provide high performance for millimeter wave band applications.