I347-AT4 Datasheet, PDF (63/148 Pages) Intel Corporation – Intel® Ethernet Network Connection I347-AT4 Datasheet

Device Functionality—I347-AT4
DC Coupled
Fault
AC Testing
Sample 0
Positive
Leg
Negative
Leg
AC Testing
Sample 1
Positive
Leg
Negative
Leg
(DC) EXTEST
Sample 0
Positive
Leg
Negative
Leg
(DC) EXTEST
Sample 1
Positive
Leg
Negative
Leg
TX- short to
RX+
1b
X
0b
X
1b
X
0b
X
TX+ short to
RX+
0b
X
1b
X
0b
X
1b
X
TX- short to
RX-
X
1b
X
0b
X
1b
X
0b
No Fault
0b
1b
1b
0b
1b
1b
1b
1b
1. A solid short to power is assumed. If the short has high inductance then a pulse can still be sent at the receiver and is mistaken
as a good connection.
2. A short on a positive and negative leg can have several behaviors on the test receiver. If both drivers cancel each other out then
the output on both legs is zero. If one driver dominates the other, then both legs are either both one or both zero. In any case,
the result is that both legs have same value.
TX+
RX+
TX
TX-
RX
RX-
Figure 16.
AC Coupled Connection
The fault detection across DC coupled connections can be detected with any one of the
AC JTAG or (DC) EXTEST commands. The DC coupled connection is shown in
Figure 17. The fault signature is listed in Table 28.
Table 28. DC Coupled Connection Fault Signature
DC Coupled
Fault
AC Testing
Sample 0
Positive
Leg
Negative
Leg
AC Testing
Sample 1
Positive
Leg
Negative
Leg
(DC) EXTEST
Sample 0
Positive
Leg
Negative
Leg
(DC) EXTEST
Sample 1
Positive
Leg
Negative
Leg
RX+ Open
0b
X
0b
X
1b
X
1b
X
RX- Open
X
0b
X
0b
X
1b
X
1b
RX+ short to
power
0b¹
X
0b¹
X
1b
X
1b
X
RX- short to
power
X
0b¹
X
0b¹
X
1b
X
1b
RX+ short to
ground
0b
X
0b
X
0b
X
0b
X
RX- short to
ground
X
0b
X
0b
X
0b
X
0b
RX+ short to ₂
2
2
2
2
2
2
2
RX-
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