System Design and Mathematical Analysis of Self-Adjusting Stable PLL

Abstract

This paper proposes a self-adjusting stable phase-locked loop circuit. According to the change of the frequency division ratio, it can use the code generated by the encoder to control charge pump charge and discharge current. Then it can change the PLL loop phase margin and fix phase margin at the required range to ensure the stability of the phase-locked loop at the same time. It also can guarantee the speed of the phase-locked loop. Meanwhile the paper has carried on the system design and mathematical analysis about the self-adjusting stable phase-locked loop circuit.