LU3X31T-T64 Single-Port 3 V
10/100 Ethernet Transceiver TX
Preliminary Data Sheet
July 2000
8
Lucent Technologies Inc.
Note: Smaller font indicates that the pin has multiple functions.
Table 7. LED and Status Outputs
Note: Smaller font indicates that the pin has multiple functions.
43
10HDEN/
LEDFD
I/O
10 Half-Duplex Enable.
The logic level of this pin is detected at powerup or
reset to determine whether 10 Mbits/s half-duplex mode is available. When
autonegotiation is enabled, this input sets the ability register bit in advertise-
ment register 4. When autonegotiation is not enabled, this input will select
the mode of operation. This pin has an internal 40 k
pull-up resistor. See
Table 7 for LEDFD description.
Pin
No.
40
Pin Name
I/O
Pin Description
LEDRX
I/O
Receive LED.
This output will drive a 10 mA LED if the LU3X31T-T64 is
receiving data from the UTP cable. This pin has an internal 40 k
pull-down
resistor. The LED should be connected as logic 0 configuration as shown in
Figure 5, without the 10 k
resistor.
Transmit LED or Activity LED.
When bit 7 of register 17h is 0, this output
will drive a 10 mA LED if the LU3X31T-T64 is transmitting data. If the control
bit is set, then the LED will be driven whenever receive or transmit activity is
present. This pin has an internal 40 k
pull-down. The LED should be con-
nected as LOGIC 0 configuration in Figure 5 without the 10 k
resistor. See
Table 5 for BPSCR description.
Link LED.
This output will drive a 10 mA LED for as long as a valid link
exists across the cable. Place a 10 k
resistor across the LED pins if setting
to nondefault mode, i.e., bypass align mode as shown in Figure 5. See Table
5 for BPALIGN description.
Collision LED.
This output will drive a 10 mA LED whenever the LU3X31T-
T64 senses a collision has occurred. Place a 10 k
resistor across the LED
pins if setting to nondefault mode, i.e., bypass 4B/5B mode as shown in Fig-
ure 5. See Table 5 for BP4B5B description.
Full-Duplex Status.
This output will drive a 10 mA LED when the LU3X31T-
T64 is in full-duplex mode. Place a 10 k
resistor across the LED pins if set-
ting to nondefault mode, i.e., 10HD disable mode as shown in Figure 5. See
Table 6 for 10HDEN description.
Speed Status.
This output will drive a 10 mA LED when the LU3X31T-T64
is in 100 Mbits/s mode. Place a 10 k
resistor across the LED pins if setting
to nondefault mode, i.e., 10FD disable mode as shown in Figure 5. See
Table 6 for 10FDEN description.
41
LEDTX/ACTLED/
BPSCR
I/O
44
LNKLED/
BPALIGN
I/O
42
LEDCOL/
BP4B5B
I/O
43
LEDFD/
10HDEN
I/O
17
LEDSP/
10FDEN
I/O
Pin
No.
Pin Name
I/O
Pin Description
Pin Descriptions
(continued)
Table 6. Autonegotiation Configuration
(Refer to Table 11.) (continued)