Adaptive bandwidth DLLs and PLLs using regulated supply CMOS buffers

A technique for designing DLLs and PLLs using CMOS buffers with a regulated supply is presented. By scaling the charge pump current and the output resistance of the regulating amplifier, the proposed loops achieve a wide bandwidth that tracks the operating frequency, a constant damping factor, large operating range and low noise sensitivity. Prototype loops designed in 0.35-/spl mu/m CMOS processes exhibit >10x operating range and less than 1% input tracking jitter.