一种可变带宽的电荷泵锁相环设计

Design of an Variable Bandwidth Charge-pump Phase Lock Loop

介绍了电荷泵鉴相器原理,提出了在电荷泵鉴相器基础上既能加快锁定时间又能在锁定时减小抖动的自适应带宽锁相环。自适应带宽是根据锁相环路的状态自动增大或减小电荷泵电流。根据此思路对传统电荷泵电路稍加改进,并用ADS2006软件进行仿真,结果表明符合预期的效果。

This article introduces the basic principle of charge pump phase detector, and then suggests a new phase-lock loop concept which can speed up the locking time and decrease jitter in lock in time. The basic idea is to increase or decrease the charge pump current according to the locking status. A circuit of charge pump is developed and simulated with ADS （ advanced design system）. The simulation result accords well with anticipated result.