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Speeding-up Phase-Locked Loops based on Adaptive Loop Bandwidth

International Journal of Computer Applications
© 2013 by IJCA Journal
Volume 61 - Number 3
Year of Publication: 2013
Dina M. El-laithy
Abdelhalim Zekry
Mohamed Abouelatta

Dina M El-laithy, Abdelhalim Zekry and Mohamed Abouelatta. Article: Speeding-up Phase-Locked Loops based on Adaptive Loop Bandwidth. International Journal of Computer Applications 61(3):1-6, January 2013. Full text available. BibTeX

	author = {Dina M. El-laithy and Abdelhalim Zekry and Mohamed Abouelatta},
	title = {Article: Speeding-up Phase-Locked Loops based on Adaptive Loop Bandwidth},
	journal = {International Journal of Computer Applications},
	year = {2013},
	volume = {61},
	number = {3},
	pages = {1-6},
	month = {January},
	note = {Full text available}


This paper describes three techniques for controlling the loop filter of the PLL for high operating speed. The proposed fast-locking PLL reduces the pull-in time and enhances the switching speed, while maintaining better noise bandwidth. Extended loop bandwidth enhancement is achieved by the adaptive control on the loop filter resistances. This work differs from previously published results in that it presents a comprehensive study for modeling, circuit simulation and practical circuit implementation of a 2nd order PLL with loop filter control for speeding-up the PLL. The overall improvement in performance of the proposed PLL is evaluated and compared with the conventional PLL. An industrial CMOS IC is used to implement the PLL.


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