Low jitter integrated phase locked loop with broad tuning range

摘要

System and method for providing low noise signal having a broad tuning range (1 GHz to 10 GHz, or larger), with associated jitter no more than about 10 percent of the selected period of a target output signal. In a first stage, a ring-based VCO phase locked loop system provides a broad tuning range with some associated noise, and a second stage in a first state is relatively transparent, with no substantial differential attenuation based on frequency. After phase lock is achieved, the second stage is switched to a second state with low associated noise and high differential attenuation based on input signal frequency.