This article examines the key noise processes involved in measurements of jitter and phase noise, shows how these processes impact test results for various types of test equipment, and provides insight for interpreting these results.
Differential clock and timing devices are commonly characterized for phase noise using baluns. While deceptively simple to use, baluns perform a fairly complicated process that can unknowingly introduce artifacts into measured results. This article describes such artifacts, discusses why they appear and how to eliminate them. Recommendations are provided for selecting a balun and using it to accurately characterize devices for phase noise.