Back-gate coupled quadrature LC VCO with multi-band tuning & low power consumption

In this paper, quadrature VCO adopts back-gate coupling instead of coupling transistor topology to get low phase noise and low power consumption. The 2-bit switch capacitor arrays and two MOS varactors are used to widen the frequency range in the band tuning circuit. As a result, the proposed LC quadrature VCO shows excellent performances of power consumption and phase noise for the frequency band of three standards: CDMA2000 lx, WCDMA, and WiBro.