A 580-μW 1.8-6 GHz multiband switched-resonator SiGeVCO with 0.3-V supply voltage

This letter presents a fully integrated low-power low-voltage multiband switched-resonator differential cross-coupled voltage controlled oscillator (VCO) implemented in 0.18 mu m SiGe-BiCMOS technology. The VCO operates with a supply voltage as low as 0.29 V, owing to the low knee-voltage provided by the technology, and consumes a total power of 580 mu W. Utilizing a switched-resonator, the VCO covers a wide switched frequency range of 1.83-2.97 GHz and 4.36-6.17 GHz with measured phase noise of around -112.2 dBc/Hz with 0.29 V supply and -119.7 dBc/Hz with 1 V supply at 1 MHz offset. Since high-frequency bands experience higher phase noise than the low frequency bands, high-Q short microstrip line inductors have been used for the high-frequency bands, To the best of the authors' knowledge, the reported VCO achieves the widest switched frequency tuning range with lowest core supply voltage.