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RTL8100B(L)
2001-11-9
Rev.1.41
9
4.6 Attachment Unit Interface
Symbol
Type
Pin No
Description
TXD+
TXD-
O
O
72
71
100/10BASE-T transmit (Tx) data.
RXIN+
RXIN-
I
I
68
67
100/10BASE-T receive (Rx) data.
X1
I
61
25 MHz crystal/OSC. input.
X2
O
60
Crystal Feedback Output: This output is used in crystal connection only.
It must be left open when X1 is driven with an external 25 MHz oscillator.
4.7 Test and Other Pins
Symbol
Type
Pin No
Description
RTT3
TEST
63
Chip test pin
RTSET
I/O
65
This pin must be pulled low by a resistor. Please refer to the application
circuit for the correct value.
VCTRL
Analog
55
Use this pin and an external PNP type transistor to generate +2.5V for
the RTL8100B(L).
NC
-
7,35,40, 52,53,
54, 69, 76, 78
Reserved