_deansbook4（外国名著）.pdf

PLL Performance, Simulation, and Design 4 th Edition Dean Ban erjee “Make Everything as S i mple as Possible, but n o t Simpler.” Albert Eins tein To my wife, Nancy, and my children, Caleb, Olivia, and Anabelle Preface I f i rs t be ca m e f a m iliar with PLL s by working for National S e m i conductor as an applications engineer. While supporting custom ers, I noticed that there were m a ny repeat questions. Instead of creating the sam e response over and over, it m a de m o re sense to cr eate a docu m ent, worksheet, or program to address these recurring q u estions in greater de tail and just r e -send the f ile. From all of these docum ents, worksheets, and program s , this book was born. Many questions concerning PLLs can be answered through a gr eater understanding of the problem and the m a them atics involved. By approaching problem s in a rigorous m a them atical way one gains a greater level of understanding, a greater level of satisfaction, and the ability to apply the concepts learned to other problem s. Many of the for m ulas that monly used for PLL design and sim u lation contain gross approxim a tions with no or little justification of how they were derived. Others may be rigor ously derived, but from outdated textbooks that m a ke as sum p tions not true of the PLL system s today. It is therefore no surprise tha t there a r e s o m a ny rules of thum b to be born which yield unreliable results. Another fault of these form ulas is that m a ny of them have not been co mpared to m easured data to ensure that they account for all relevant factors. There is also the approach of not trusting formulas enough and relying on only m e asured results. The f a ult with this is that many great in sights ar e lo st and it is d i f f i cult to le arn and grow in PLL knowledge this way. Furthe rm ore, by knowing what a result should theoretically be, it m a ke s it easier to spot and diagnose