Appendix B: Automatic Measurements Reference
CSA8000B & TDS8000B User Manual B-35
Table B- 5: RZ Measurements - Timing (cont.)
Name Definition
RZ RMS Jitter Jitter is the measure of time variance at the location where the signal crosses the mid-reference
level. RMS Jitter is defined as one standard deviation (σ) of that variance. The mean of the
histogram of the crossing data distribution is Tcross.
RMS Jitter = Tcrossσ
The mid-reference level is adjustable and defaults to 50% of the RZ maximum pulse amplitude.
The jitter measurement can be performed on the positive or negative slope. See Mid-reference
level on page B--69.
The slope can be selected to be the first positive, the first negative, or the first crossing (positive
or negative) in the region.
If enabled, measurement gates constrain the measurement region to the area between the Start
Gate (G1) and Stop Gate (G2). By default, the algorithm searches forward from the Start Gate
for the first specified edge, but the Direction of traversal can be reversed, so that the search will
be backward from the Stop Gate. See To Localize a Measurement on page 3--83.
This measurement requires the use of a waveform database. When this measurement is turned
on, it will automatically set the measurement system to use a waveform database if available.
See Use a Waveform Database on page B--70.
RZ +Width The time interval between the crossings of the rising and falling edges at the mid-reference
level.
+Width = Tcross2 –Tcross1
Where Tcross1 and Tcross2 are the mean of the histogram of the rising and falling
crossings.
The mid-reference level is adjustable and defaults to 50% of the RZ pulse amplitude.
If enabled, measurement gates constrain the measurement region to the area between the Start
Gate (G1) and Stop Gate (G2).
This measurement requires the use of a waveform database. When this measurement is turned
on, it will automatically set the measurement system to use a waveform database if available.