Design of A Double-PLLs with Highs Performance
Zhongyi Hu · 2010
PLL frequency synthesizer is a kind of indirect frequency-synthesizing.It is a negative feedback-control-system which is based on phase-comparing.But,because of including only one voltage-control-oscillator,the conventional PLL can 't oscillate over multiple frenquency ranges,which limits the frequency spectrum range of PLL's output.This paper gives a example of designing the control-system with two PLLs.This system's output signal could cover with wide frequency spectrum and hold high stability.The results show that this circuit not only has achieved the anticipant target,but also adapt to be mass produced.It will provide well experience and reference for others who want to study similar PLLs more deeply.