LOW JITTER LARGE FREQUENCY TUNING LC PLL FOR MULTI-SPEED CLOCKING APPLICATIONS

摘要

ABSTRACT The subject innovation relates to systems and/or methodologies for generating a low jitter large frequency tuning LC-based phase-locked loop circuit for multi-speed clocking applications. In addition to a plurality of noise reduction features, the phase-locked loop includes programmable charge pump and loop filter that enable a wide loop bandwidth, a programmable VCO that enables a wide VCO frequency range and a per lane clock divider that further enables a wide PLL frequency range. Furthermore, an auto-calibration circuit ensures that the VCO included in the PLL receives the optimum current for noise reduction across the VCO frequency range.