采用锁相环(PLL)的频率合成器具有良好的性能价格比。尤其是近年来,随着集成电路的迅速发展,一些新的频率合成器不断涌现。从环路结构上看,也各有利弊。最近提出一种“分数分频锁相环”其优点有:1.只采用单个锁相环,结构非常简单;2.频率分辨力可以做得 The frequency synthesizer that adopts phase-locked loop (PLL) has good performance-cost ratio. Especially in recent years, with the rapid development of integrated circuits, some new frequency synthesizers continue to emerge. From the loop structure point of view, there are advantages and disadvantages. Recently proposed a “fractional frequency PLL,” its advantages are: 1. Only a single phase-locked loop, the structure is very simple; 2. Frequency resolution can be done