SMSC LAN9311 User Manual
Two Port 10/100 Managed Ethernet Switch with 16-Bit Non-PCI CPU Interface
Datasheet
SMSC LAN9311/LAN9311i
29
Revision 1.4 (08-19-08)
DATASHEET
Note 3.1
The pin names for the twisted pair pins apply to a normal connection. If HP Auto-MDIX is
enabled and a reverse connection is detected or manually selected, the RX and TX pins
will be swapped internally.
enabled and a reverse connection is detected or manually selected, the RX and TX pins
will be swapped internally.
Note 3.2
The pin names for the twisted pair pins apply to a normal connection. If HP Auto-MDIX is
enabled and a reverse connection is detected or manually selected, the RX and TX pins
will be swapped internally.
enabled and a reverse connection is detected or manually selected, the RX and TX pins
will be swapped internally.
Table 3.2 LAN Port 2 Pins
PIN
NAME
SYMBOL
BUFFER
TYPE
DESCRIPTION
83-86
Port 2 LED
Indicators
nP2LED[3:0]
OD12
LED indicators: When configured as LED outputs
via the
via the
,
these pins are open-drain, active low outputs and
the pull-ups and input buffers are disabled. The
functionality of each pin is determined via the
LED_CFG[9:8] bits.
the pull-ups and input buffers are disabled. The
functionality of each pin is determined via the
LED_CFG[9:8] bits.
General
Purpose I/O
Data
GPIO[7:4]
IS/O12/
OD12
(PU)
General Purpose I/O Data: When configured as
GPIO via the
GPIO via the
, these general purpose signals are
fully programmable as either push-pull outputs,
open-drain outputs or Schmitt-triggered inputs by
writing the
open-drain outputs or Schmitt-triggered inputs by
writing the
. The
pull-ups are enabled in GPIO mode. The input
buffers are disabled when set as an output.
buffers are disabled when set as an output.
Note:
See
for additional details.
127
Port 2
Ethernet TX
Negative
TXN2
AIO
Ethernet TX Negative: Negative output of Port 2
Ethernet transmitter. See
Ethernet transmitter. See
for additional
information.
126
Port 2
Ethernet TX
Positive
TXP2
AIO
Ethernet TX Positive: Positive output of Port 2
Ethernet transmitter. See
Ethernet transmitter. See
for additional
information.
124
Port 2
Ethernet RX
Negative
RXN2
AIO
Ethernet RX Negative: Negative input of Port 2
Ethernet receiver. See
Ethernet receiver. See
for additional
information.
123
Port 2
Ethernet RX
Positive
RXP2
AIO
Ethernet RX Positive: Positive input of Port 2
Ethernet receiver. See
Ethernet receiver. See
for additional
information.
Table 3.3 LAN Port 1 & 2 Power and Common Pins
PIN
NAME
SYMBOL
BUFFER
TYPE
DESCRIPTION
119
Bias
Reference
EXRES
AI
Bias Reference: Used for internal bias circuits.
Connect to an external 12.4K ohm, 1% resistor to
ground.
Connect to an external 12.4K ohm, 1% resistor to
ground.
114,117
+3.3V Port 1
Analog Power
Supply
VDD33A1
P
+3.3V Port 1 Analog Power Supply
Refer to the LAN9311/LAN9311i application note
for additional connection information.
for additional connection information.