The Role of Jitter in Timing Signals

Timing signal jitter can have a profound impact on a wide variety of applications from analog radio frequency (RF) or audio to digital communications. While information in a communications system, for example, is extracted from serial data streams by sampling the data signal at specific points, the presence of small quantities of jitter can alter the edge positions enough to lead to data errors and high bit-error rates. Complicating the measurement of jitter is the way it is specified. Generally, timing signal jitter is specified in different ways from one application environment to another. For example, in digital data path synchronization applications, jitter is specified in the time domain as period or cycle-to-cycle jitter. In data communications applications, on the other hand, jitter is specified in the frequency domain as phase noise or "root mean square" (RMS) jitter.

This paper provides a basic tutorial on timing signal jitter for designers building electronics systems. It defines this phenomenon and describes how it is measured in different applications.