<formula formulatype="inline"><tex Notation="TeX">$G_{m}$</tex> </formula>-Boosted Complementary Current-Reuse Colpitts VCO With Low Power and Low Phase Noise

Abstract

In this letter, a transformer-based current-reuse Colpitts voltage controlled oscillator (VCO) is proposed, which combines a N-type and P-type Colpitts oscillators using a 5-port transformer in a complementary form to provide the differential outputs. The proposed VCO has low phase noise due to the low noise Colpitts oscillator topology and the negative- ${Gm}$ boosting technique with half of the DC-current consumption using the current-reusing method. The proposed VCO has the frequency tuning range from 8.57 to 10.21 GHz, and shows low phase noise of $-110.6~{\rm dBc}/{\rm Hz}$ at 1 MHz offset frequency at 9.41 GHz and high figure of merit with tuning range ( ${\rm FoM}^{T}$ ) of $-191.8~{\rm dBc}/{\rm Hz}$ . The power consumption is 2.1 mW from 1.2 V supply voltage. The VCO is implemented using 0.13 $\mu {\rm m}$ CMOS process with chip area of 0.45 ${\rm mm}^{2}$ .