Design of a sub-1-V low dropout regulator for supply-regulated active-loop-filter VCOs

摘要

Full-swing voltage-controlled oscillators (VCOs) are very sensitive to supply noises and require supply regulators with increased supply voltages, which may entail more power consumption. Further, in a phase-locked loop (PLL) with a conventional second-order passive-loop filter (PLF), PLL output frequency range is restricted by the compliance range of the charge pump output voltage (V cp) even though supply-regulated vCos (SR-VCO) can provide a wider frequency range. In order to solve these problems, V Cp be separated from the V CTRL using the low dropout regulator (LDO). This paper proposes a low dropout regulator of O.83V with bandgap references (BGR) ofO.62V output voltage in supply-regulated active-loop filter vCos (SR-ALF-VCO).