A Reference Oversampling Digital Phase-Locked Loop with -240 dB FOM and -80 dBc Reference Spur

Abstract

This paper proposes a reference oversampling phase-locked loop that simultaneously suppresses in-band noise and oscillator noise while maintaining a low reference spur. The proposed phase locked loop achieves -240.3 dB Figure of Merit (FOM) and -80 dBc reference spur. The integrated jitter is 508 fsrms and the power consumption is 3.6 mW at 2 GHz output clock frequency.