Education Library

Frequently Asked Question

How do you specify jitter?

Jitter is specified statistically as the root mean square of the time deviation (over many cycles) between the actual clock edges and an ideal clock of the same frequency. The rms value corresponds to one sigma, or a standard deviation, of a normal distribution. This applies only to truly random jitter, and not to any pattern jitter which may be present due to crosstalk between outputs. A good estimate of the peak-to-peak jitter (as normally used) is to multiply the rms value by six.