Comparison and analysis of various PFD architecture for a phase locked loop design

Phase Frequency Detector (PFD) plays a crucial role and an essential part in Phase Locked Loop (PLL). PFD has an advantageous function over the Phase Detector (PD) and Frequency Detector (FD) by detecting phase and frequency detection at a time. PFD compares the phase difference between the input reference signal and the output signal from voltage controlled oscillator (VCO). Generation of Up and Down clock signals depend upon phase and frequency deviation. The key factor is to observe the dead zone problem in various PFD structures. This Paper presents the Comparison and Analysis of different PFD architectures, designed and simulated using T-Spice in 130nm technology.