User`s guide

Manual Channel Skews
This step is optional, it allows fixed time offsets
to be added to or subtracted from a channel
when a Channel-to-Channel measurement is
made. This can be used to compensate for
different cable delays between channels. This
will affect all channel-to-channel measurements
or any measurement such as DataBus, Random
Data w/ Bit Clock or any measurement using
one channel as a “reference”. To clear these
values, press “Reset”. The values will also reset
to zero if the instrument is powered down.
Manual Channel Skew Setup
Only enter values here if the delay differences between channels are known. When using
differential inputs, the cables connected to each pair of channel inputs must be a matched set.
The values entered are relative to one of the channels; one value will always be left at 0.0000.
• Select “Manual Channel Skews”.
• A dialog window appears allowing the user to enter relative channel skews. Enter values in
picoseconds.
In the figure to the right, example
values are shown. The values that are
input are the differences between
channels, not the absolute electrical
length of a cable on that channel.
For instance, Channel 1 cable is
2.80ns. Channel 2 cable is 2.8205ns.
So the value entered in “Channel 2” is
the difference, 20.5 ps. Note: in this
example, Channel 5 is 14ps shorter
than Channel 1.
Manual Channel Skews
The
SIA-3000 is now ready to make
measurements.
Appendix C © WAVECREST Corporation 2005
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