自偏置锁相环结构及其稳定性条件分析

给出了基于自偏置技术的电荷泵锁相环电路，压控振荡器的工作频率动态地建立了电路内部所有的偏置电压和电流，从而实现了固定衰减因子，固定环路带宽与工作频率之比，这二者由电容的比率决定，极大地实现了电路设计的工艺无关性，同时也得到了小的相位抖动，最后，对这种锁相环的稳定性进行了一定的分析。

An Analysis of a Self-Biased Phase-Locked-Loop and Its Stability

A charge pump phase locked loop (PLL) based on self biased technique is presented. In this technique, the operating bias levels are essentially established by the operating frequency of the voltage controlled oscillator (VCO), namely, all bias voltages and currents are determined by VCO controlling voltage. Thus, a fixed damping factor and a fixed ratio of the bandwidth to operating frequency are obtained, which are defined by the ratio of capacitors. A low input tracking jitter, process independent design is achieved. An analysis on the stability of the PLL circuit is also described.