Verification of embedded phase-locked loops

Abstract

With the increasing use of Phase-locked loops (PLLs) embedded in FPGAs, ASICs, and System-On-Chip (SoC), there is a growing need for methods to verify, their operation. This paper describes a general and organized list that includes tests for lock, jitter, stability and modulation response. The list is offered as a guide to the verification and testing of an embedded PLL. For that reason it is presented in such a way as to allow the reader to determine the extent to which the verification will be carried out. The tests are covered from the easiest to the most complicated to perform, with the amount of information gathered increasing along with the complexity of the test. The paper also discusses the difference between observing a stand-alone PLL and an embedded PLL.