Design of Analog CMOS Integrated Circuits
Design of Analog CMOS Integrated Circuits
Phase frequency detector with minimal blind zone for fast frequency acquisition
IEEE Transactions on Circuits and Systems II: Express Briefs
Hi-index | 0.00 |
The gain of a widely used sequential-type phase/ frequency detector (PFD) as a function of its input frequency is modeled adopting a continuous-time approximation. High-frequency gain degradation is described by a frequency-dependent attenuation factor characterized in terms of the propagation delays of the PFD. The attenuation factor can be readily included in the dynamics equations of phase-locked loop to account for the effect of the PFD degradation. Gain-modeling-related delay components of a complimentary metal-oxide-semiconductor PFD are also described. The high-frequencymodel is in good agreement with the simulation results of the PFD.