Low-phase-error and low-phase-noise 2GHz CMOS quadrature VCOs

This paper presents a low-phase-error and low-phase-noise quadrature-voltage-control-oscillator (Q VCO). The mutual inductance effect, which has a very severe effect on the phase-error performance, is minimized by implementing a new layout design. The losses of the tank are also minimized since a more compact layout is achieved. The QVCOs were implemented in a standard CMOS 0.35μ process. The center frequency is 2GHz, and the tuning range is 15%. The new implementation presents a 45dB image-band-rejection (IBR) ratio and the phase noise measured is -140dBc at 3MHz offset frequency, with a QVCO core power dissipation of 32mW at 2V power supply.