Keysight Technologies E5400-Pro Series, User Manual

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Keysight Technologies E5400-Pro Series Soft Touch Connectorless Probes User’s Guide 31
Mechanical Considerations 2
If you ever plan on upgrading from a 40-pin to a 90-pin logic analyzer to
take advantage of higher state speed and differential probing on the clock
channel, some steps should be taken so that the original footprint will
work for both the E5404A and the E5406A probes.
• If you are driving only single-ended clocks into A7 (CK1+) and B21
(CK2+), then you should ground A8 and B20. A8 and B20 are where
CK1- and CK2- are driven in the E5406A probe. Grounding these
pads will allow the user-defined threshold in the analyzer to be used
as in normal single-ended operation.
• If you are using differential clocks, route the Odd pod clock such that
the positive side of the pair goes to A7 (CK1+) and the negative side
of the pair goes to A8 (CK1-). Similarly, route the Even pod clock
such that the positive side of the pair goes to B21 (CK2+) and the
negative side of the pair goes to B20 (CK2-). When using the
E5404A probe, A8 and B20 are unused. However, when using the
E5406A probe, A8 and B20 are where the probe connects to the
negative sides of the clocks' differential pair.