83C694D Datasheet, PDF (14/33 Pages) SMSC Corporation – Twisted-Pair Interface and Manchester Encoder/Decoder

PIN DESCRIPTION
83C694D
PIN
NUMBER
8
9
10 – 13
14
15
MNEMONIC SIGNAL NAME I/O
DESCRIPTION
LNK
TPOL
GND
RLED
XLED
TwPr Link Status O
TwPr Link Polarity O
Negative Supply
Receive LED
O
Driver
Transmit LED
O
Driver
If valid data or Link Test pulses are received
on TPR+/TPR-, LNK is low (link status OK).
When no data or Link Test pulses are re-
ceived, LNK is high. The LNK pin can sink
10mA to drive an external LED.
TPOL is low when positive polarity Link Test
pulses or data packets are received on
TPR+/TPR- (normal operation). TPOL is high
when negative polarity Link Test pulses or
data packets are received (link wiring polarity
reversed). When TPOL is low, it can sink
10mA to drive an external LED.
Pin 10 provides negative supply for analog
circuits. Pin 11 provides negative supply for
digital circuits. Pin 12 provides negative sup-
ply for digital/pad circuits. Pin 13 provides
negative supply for VCO circuits.
When active low, RLED sinks 10 mA to drive
an external LED. If no data is received, RLED
is high. If data is received, RLED will go low
for approximately 50ms longer than the re-
ceived packet length.
All LED current is controlled internally and
requires no external resistors between the
chip and an external LED.
The external LED must be connected from
+5V to the device pin. If LEDs are not used,
then the four pins can be used as logic out-
puts.
When active low, XLED sinks 10mA to drive
an external LED. When there is no transmis-
sion (TXE inactive), XLED is high. When data
is transmitted, XLED goes active low for ap-
proximately 50ms longer than the transmitted
packet length. XLED does not go active low
for Link Test pulses.
TABLE 3-1. PIN DESCRIPTION cont.
11