Analysis and Design of Bang-Bang PD-Based Phase Noise Filter

In this paper, we present a bang-bang phase detector (BBPD) and a delay-line frequency discriminator-based phase noise filter (PNF). With a larger phase detection gain, the BBPD-based PNF enhances the sensitivity by suppressing the charge pump noise. A time-amplifier and a five times voting machine are introduced together with the sense-amplifier-flip-flop to minimize the BBPD noise to make its effects negligible in the PNF sensitivity. At 1-MHz offset, the PNF demonstrates 15-dB phase noise suppression with -120.2-dBc/Hz sensitivity. Its phase noise suppression offset frequency is from 100 kHz to 8 MHz with 10-10.1-GHz input frequency range. The circuit is fabricated in a 65-nm CMOS technology, and dissipates 98-mW power.