User`s guide

A quick test to check Deskew Calibration
The GigaView software can be used to check the calibration.
The deskew calibration has two parts. The first part is the internal channel Deskew Calibration
that deskews a channel path. To check this calibration, do the following.
• Connect the calibration signals to the channel you want to check. (Make sure the
'Normal Calibration Output State' in the Calibration menu is set to '900MHz sine –
Out of Phase'.)
• Open the
tool. Press Pulse Find and GO (Make sure that the measurement
is set to 'Period'.)
• The Histogram should be comparable to the figure below.
• If the Period is 1.111ns ±10ps the Deskew cal is good.
The second part of the deskew cal is the channel-to-channel skew. To check this, do the following.
• Connect the top calibration signal to the top input of channel1 and the bottom calibration
input to the top of channel 2. (Make sure the 'Normal Calibration Output State' in
the Calibration menu is set to '900MHz sine – In Phase'.)
• Open the 'Multichannel | Propagation Delay and Skew' tool. Press Pulse Find
and GO
(make sure that the measurement is set to 'Period')
• The Histogram should be comparable to the above figure.
• If the skew is 0ps ±30ps the Deskew cal is good.
Repeat this for any channels that you want to measure between.
© WAVECREST Corporation 2005 Appendix C
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