NOVEMBER 1998
General Description
Features
LXD970A Demo Board
for 10/100 and 100BASE-FX applications
LXD970 Demo Board
USER GUIDE
Revision 1.3
The LXD970A Demo Board is a versatile 10/100Mbps
Ethernet media access unit (MAU) that demonstrates all of
the integral features of the LXT970A Fast Ethernet
Transceiver.
The LXD970A provides a working platform for evaluation
of the LXT970A Fast Ethernet Transceiver in 10BASE-T
and/or 100BASE-TX/FX applications.
The LXD970A Demo Board is configured with a single
chip 10/100Mbps, IEEE 802.3u compliant, Fast Ethernet
Transceiver unit (LXD970A). The demo board is designed
to plug into a transceiver test box via a standard 40-pin MII
connector. This allows system designers to test 10Mbps
and 100Mbps link performance, auto-negotiation and
register functionality prior to board prototyping.
The LXT970A also provides an ECL-type interface for
100BASE-FX link testing.
This document describes typical Demo Board setup
procedures for a 100BASE-TX environment.
Before using the Demo Board, review the LXT970A Fast
Ethernet Transceiver data sheet for device functionality
and specifications.
• IEEE 802.3-compliant 10BASE-T and 100BASE-TX
using a single RJ45 connection.
• Quick setup, ease of use, and clear visibility of appli-
cation settings for:
- Complete system demonstration
- Individual circuit isolation
• LED indicators for major functions.
• IEEE 802.3u MII interface with extended register
capability.
• Configured for single 5V supply operation.
• Standard half duplex or full duplex operation at 10 or
100 Mbps.
• 100BASE-FX fiber optic capability (unstuffed
optional circuitry).
E N B L
C O L
L N K
T X
R X
O p t i o n a l
F I B E R M O D U L E C I R C U I T
M F 1
M F 2
M F 3
M F 4
M F 0
T S T O P
I B T S T
T S T O N
J P 7
M
A N
0
J P 8
T E S T
J P 5
T D +
T D -
R D +
R D -
M D I N T
G N D R
G N D T
J P 6
M
A N
1
M
A N
2
J P 1
J P 3
J P 4
M I I
R J 4 5
T R A N S F O R M E R
LXT970A
L E D s