4.3.3.2 Remove External Factors on Cable or Link Partner
Change the link partner board to
the same as DUT board
This isolates the root
cause on the Link Partner side
Remove the cable, enable loopback
(analog loopback is preferred) on the PHY, and perform the ESD test to eliminate
the effect of cable and link partner
Analog Loopback can
connect the Transmitter and Receiver on the MDI side together inside the
PHY and causing the PHY to link to itself. The MDI lines can still
receive ESD noise externally after loopback configuration.
If a passing result is
observed after loopback configuration, the issue is most likely on the
cable or link partner side.