A bang-bang PD based phase noise filter with 23 dB noise suppression

In this paper, we present a bang-bang phase detector (BBPD) and delay-line frequency discriminator (FD) based phase noise filter (PNF). With a larger phase detection gain, the BBPD based PNF enhances the phase noise cancellation and sensitivity by suppressing the charge pump (CP) noise. A time-amplifier (TA) and a 5 × voting machine are introduced together with the modified sense-amplifier-flip-flop (SAFF) to minimize the BBPD random noise. At 1 MHz offset, the maximum phase noise suppression is 23 dB and best phase noise sensitivity is -120.2 dBc/Hz. Its phase noise suppression offset frequency is from 100 kHz to 8 MHz with 100 MHz input frequency range. The circuit is fabricated in a 65 nm CMOS technology and dissipates 98 mW power.