A widebound low phase noise LC-VCO based PLL with automatic amplitude control

摘要

This paper forcuese on a low phase noise LC-VCO based PLL using CP-AAC circuit for output amplitude control. A wide tuning range (2.796GHz-3.86GHz) is achieved by dividing the total tuning range into 8 sections. As it is needed a digital unit is designed to choose the correct suband. To compensate the KVCO degradation over entire frequency range which cause instability, charge pump current is increased on the opposite direction. Total rms jitter is about 1.5ps. This PLL architecture has been simulated in standard of 0.18μm CMOS technology with 1.8V power supply.