Fast Charge Pump Phase Locked Loop with a BBFC: A Numerical Confirmation

Speeding up a synthesizer’s locking process can be considered as speeding up the charge pump PLL. Several methods have been introduced to increase the speed of the locking process. One way to achieve fast locking is to use a bangbang frequency comparator (BBFC) in the feed-trough path to achieve a faster locking process. In this paper, we present a differential equation for this fast CPPLL which shows how the BBFC can decrease the settling time in a charge pump PLL. Simulations in MATLAB are confirmed by a differential equation solved in Maple using a numerical method. Using the extracted equation and solving it by numerical method we can predict the system’s behavior