Comprehensive Study of the Third-order Charge Pump PLL Dynamic Behavior

This paper provides useful equations for the analysis of loop dynamics specification such as damping ratio, overshoot and settling time in the third-order charge pump PLL with second-order loop filter. The presented analysis method is based on the approximation of the output phase step response using the step response of the second-order systems. In fact, the results can be used as an accurate approximation in the design and analysis of third-order PLL. The performance of this method has been verified in an interesting example using behavioral simulations in MATLAB. Simulations demonstrate a significant agreement between the simulated results of the actual PLL and the proposed approximated approach