Jitter measuring device and method

摘要

A signal to be measured is waveform-formatted to a square waveform that retains the frequency, duty ratio and jitter component of the original signal, and the leading (or trailing) edge of the waveform-formatted output is sampled by a sampling clock of a frequency slightly different from 1/N of the frequency fM of the signal to be measured. The samples are converted by an A/D converter to digital data Vn(t), which is stored in a memory. The difference between the stored digital data Vn(t) and the rise-up characteristic line V'(t) is calculated to detect jitter J'n(t).