Teledyne LeCroy QPHY-HDMI - Manual (Page 35)

QPHY-HDMI Operator’s Manual
7. Set the resulting value as the Deskew value in C2 menu.
8. Restore the cable connections to their Step 1 settings (previous). Press the Clear
Sweeps button on the oscilloscope. The mean skew value should be approximately zero
- that is the data skew. Typically, results are <1ps given a test fixture meant to minimize
skew on the differential pair.
9. On the C3 dialog, un-check the Invert checkbox and turn off the parameters.
Now that the oscilloscope inter-channel skew and cable skew is compensated for, you
are ready to test.
The procedure as given above relies on the default setup of the Skew parameter (which is:
detecting positive edges on both signals, at 50%). C3 was inverted in order to make C2 and C3
both have positive edges at the same time. The default setup of any parameter is in effect at the
time it is set up.
Figure 4 - The Skew parameter right side dialog, Skew clock 2 tab, showing default setup.
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