LAN9303 Evaluation Board User Manual
Revision 1.0 (05-28-09)
USER MANUAL
SMSC LAN9303
2
1 Introduction
The LAN9303 is a full featured, three-port 10/100 managed Ethernet switch designed for embedded
applications where performance, flexibility, ease of integration and system cost control are required.
The LAN9303 combines all the functions of a 10/100 Ethernet switch system, including the Switch
Fabric, packet buffers, Buffer Manger, MACs, PHY transceivers, and serial management. The
LAN9303 complies with the IEEE 802.3 (full/half-duplex 10BASE-T and 100BASE-TX) Ethernet
protocol specification and 802.1D/802.1Q management protocol specifications, enabling compatibility
with industry standard Ethernet and Fast Ethernet applications.
The EVB9303 is an Evaluation Board (EVB) that utilizes the LAN9303 to provide a fully functional
three-port single MII/RMII/Turbo MII Ethernet switch. The EVB9303 provides two fully integrated
MAC/PHY Ethernet ports (Ports 1 & 2) via on-board RJ45 connectors. Port 0 provides two MII port
connectors which support the following:
An external MII-/RMII-/Turbo MII-capable MAC (with LAN9303 in PHY mode), via the onboard 40-
pin male MII connector
An external MII-/Turbo MII-capable PHY (with LAN9303 in MAC mode), via the onboard 40-pin
female MII connector
The Port 0 mode of operation is configured via a single, 8-position, mode-configuration strap switch.
Power is supplied to the board via a +5V external wall-mount power supply. The external supply is not
necessary when Port 0 is configured for (and used in) PHY mode. In such cases, the +5V power rail
is typically supplied through the MII connector from the MAC side.
The EVB9303 includes a 8Kx8 I
2
C EEPROM that may be used to automatically load configuration
settings from the EEPROM into the device at reset, allowing the device to operate unmanaged. An I
2
C
host adapter interface header (10-pin, 2x5) is provided to simplify I
2
C based configuration. A simplified
block diagram of the EVB9303 can be seen in
Figure 1.1 EVB9303 Block Diagram
EVB9303
Ethernet
10/100
Ethernet
Magnetics &
RJ45
Jumper
SMSC
LAN9303
Ethernet
10/100
Ethernet
Magnetics &
RJ45
8K x 8
I
2
C
EEPROM
Port0
I
2
C Host
Adapter I/F
Port2
Port1
Mode Switch
40-Pin MII
Connector
(Male)
40-Pin MII
Connector
(Female)
To
external
MAC
To
external
PHY
