A Fully Integrated 20-GHz Frequency Synthesizer in 0.13-μm BiCMOS

This paper presents a fully integrated 20-GHz frequency synthesizer based on an integer-N fourth-order type-II phase-locked loop (PLL). The PLL synthesizer employing a cross-coupled LC VCO was fabricated in a 0.13-μm SiGe:C BiCMOS process with a small chip area of 0.48 mm. The VCO core current is 4 mA. The full tuning range of the VCO is 2.21 GHz from 19.9 to 22.11 GHz, and the PLL can synthesize output frequencies from 20.51 to 21.27 GHz. The phase noise at 100-kHz and 1-MHz offset frequencies from the carrier is −68.66 dBc/Hz and −97.17 dBc/Hz, respectively. The total power consumption of the synthesizer is 40 mW at a 1.5-V voltage supply. The frequency synthesizer can be used as a frequency source in highly-integrated wireless applications.