User`s guide

Serial ATA Theory of Operation
The SATA Specification requires that jitter measurements be made from Data edge to Data edge across
varying spans. The spans are from 0 to 5 UI, and then from 6 to 250 UI. This tool automates these
measurements and provides pass/fail results. For the specification point A2, or 25,000 UI, a 1010
pattern is used and the Low Frequency Modulation tool can be used.
This tool requires no knowledge of the data stream prior to making a measurement. It simply measures
data edge to data edge and places the measurements in their relative bins. The bin size is base on the
"Bit Rate (Gb/s)" entered into the tool plus or minus 0.5 UI. For example, if a span of 1.12UI is
measured, it is placed in the 1UI bin. Some random time later, another measurement is made and is
2.34 UI, so it is placed in the 2UI bin. After each bin has sufficient data, a TailFit is performed on each
UI span to get RJ, DJ and TJ at 10-12 BER.
© WAVECREST Corporation 2005 Section 4 - GigaView
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