LAN9420 Datasheet, PDF (19/171 Pages) SMSC Corporation – Single-Chip Ethernet Controller with HP Auto-MDIX Support and PCI Interface

Single-Chip Ethernet Controller with HP Auto-MDIX Support and PCI Interface
Datasheet
NUM
PINS
NAME
Crystal Input
1
1
Crystal
Output
Ethernet TX
1
Data Out
Negative
Ethernet TX
1
Data Out
Positive
Ethernet RX
1
Data In
Negative
Ethernet RX
1
Data In
Positive
External
1
PHY Bias
Resistor
Table 2.5 PLL and Ethernet PHY Pins
SYMBOL
XI
XO
BUFFER
TYPE
DESCRIPTION
ICLK
OCLK
Crystal Input: External 25MHz crystal input. This pin
can also be driven by a single-ended clock oscillator.
When this method is used, XO should be left
unconnected.
Crystal Output: External 25MHz crystal output.
TPO-
TPO+
TPI-
TPI+
EXRES
AIO
Ethernet Transmit Data Out Negative: The transmit
data outputs may be swapped internally with receive
data inputs when Auto-MDIX is enabled.
AIO
Ethernet Transmit Data Out Positive: The transmit
data outputs may be swapped internally with receive
data inputs when Auto-MDIX is enabled.
AIO
Ethernet Receive Data In Negative: The receive data
inputs may be swapped internally with transmit data
outputs when Auto-MDIX is enabled.
AIO
Ethernet Receive Data In Positive: The receive data
inputs may be swapped internally with transmit data
outputs when Auto-MDIX is enabled.
AI
External PHY Bias Resistor: Used for the internal
PHY bias circuits. Connect to an external 12.4K 1.0%
resistor to ground.
SMSC LAN9420/LAN9420i
19
DATASHEET
Revision 1.6 (07-18-11)