This book is intended for the reader who wishes to gain a solid understanding of Phase Locked Loop architectures and their applications. It provides a unique balance between both theoretical perspectives and practical design trade-offs. Engineers faced with real world design problems will find this book to be a valuable reference providing example implementations, the underlying equations that describe synthesizer behavior, and measured results that will improve confidence that the equations are a reliable predictor of system behavior. New material in the Fourth Edition includes partially integrated loop filter implementations, voltage controlled oscillators, and modulation using the PLL.