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Voltage Histogram

This measurement is similar to the jitter histogram except that it is done in the vertical domain. It shows the amount of voltage noise that exists on the high-speed serial signal and is similar in principle to the vertical eye height.Click the Voltage Histogram tab to see a voltage histogram. The display above shows a sample voltage histogram. By default, the histogram is taken over a time window corresponding to a single UI, centered on the eye. This measurement does not directly relate to jitter. It is data dependent and will provide a graphical representation of signal changes in the voltage domain such as what the effect is of signal pre-emphasis or data dependent patterns.
The extent can be changed dynamically, after the acquisition is complete, via the Time Extent control. For the oscilloscope measurement for example, a Time Extent of 10% would measure a voltage histogram for the 40 ps (10% of one UI) centered at 440 ps (the center of the eye).