A SAR Fast-Locking Digital Phase-Locked Loops: Behavioral modeling and simulations using matlab/simulink.

摘要

A Successive-Approximation Register Fast-Locking Digital Phase-Locked Loop (SAR DPLL) is presented and behaviorally modeled using MATLAB/Simulink. The DPLL operation includes two stages: (1) a SAR coarse-tuning stage for frequency tracking, which employs a successive-approximation algorithm similar to the one employed in SAR A/D converters (ADCs) and (2) a fine-tuning stage for phase tracking, which is similar to conventional DPLLs. The coarse-tuning stage includes a phase frequency detector, a successive-approximation register, a D/A converter (DAC), and control logic. MATLAB/Simulink are used to design and perform simulations. The fast-locking DPLL saves about 50 percentage of the lock time as compared to its conventional DPLL counterpart.