SMSC LAN9512 Switch User Manual


 
USB Hub with Integrated 10/100 Ethernet Controller
Datasheet
SMSC LAN9512 13 Revision 1.0 (04-20-09)
DATASHEET
1
External USB
Bias Resistor
USBRBIAS AI Used for setting HS transmit current level and on-
chip termination impedance. Connect to an
external 12K 1.0% resistor to ground.
1
USB PLL +1.8V
Power Supply
VDD18USBPLL P Refer to the LAN9512 reference schematics for
additional connection information.
1
Crystal Input XI ICLK External 25 MHz crystal input.
Note: This pin can also be driven by a single-
ended clock oscillator. When this method
is used, XO should be left unconnected
1 Crystal Output XO OCLK External 25 MHz crystal output.
Table 2.5 Ethernet PHY Pins
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
1
Ethernet TX
Data Out
Negative
TXN AIO Negative output of the Ethernet transmitter. The
transmit data outputs may be swapped internally
with receive data inputs when Auto-MDIX is
enabled.
1
Ethernet TX
Data Out
Positive
TXP AIO Positive output of the Ethernet transmitter. The
transmit data outputs may be swapped internally
with receive data inputs when Auto-MDIX is
enabled.
1
Ethernet RX
Data In
Negative
RXN AIO Negative input of the Ethernet receiver. The receive
data inputs may be swapped internally with
transmit data outputs when Auto-MDIX is enabled.
1
Ethernet RX
Data In Positive
RXP AIO Positive input of the Ethernet receiver. The receive
data inputs may be swapped internally with
transmit data outputs when Auto-MDIX is enabled.
7
+3.3V Analog
Power Supply
VDD33A P Refer to the LAN9512 reference schematics for
connection information.
1
External PHY
Bias Resistor
EXRES AI Used for the internal bias circuits. Connect to an
external 12.4K 1.0% resistor to ground.
1
Ethernet PLL
+1.8V Power
Supply
VDD18ETHPLL P Refer to the LAN9512 reference schematics for
additional connection information.
Table 2.4 USB Pins (continued)
NUM
PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION