ML4663
PIN DESCRIPTION
PIN
NAME
FUNCTION
PIN
NAME
FUNCTION
1
CLSN
Indicates that a collision is taking
place. Active low LED driver, open
collector. Event is extended with
internal timer for visibility.
Gated 10MHz oscillation used to
indicate a collision, SQE test, or
jabber. Balanced differential line
driver outputs that meet AUI
specifications.
A capacitor from this pin to V
CC
determines the Link Monitor
response time.
15
XMT
Indicates that transmission is taking
place. Active low LED driver, open
collector. Event is extended with
internal timer for visibility.
Indicates that the transceiver is
receiving a frame from the optical
input. Active low LED driver, open
collector. Event is extended with
internal timer for visibility.
+5 volt supply for fiber optic LED
driver.
Fiber optic LED driver output.
Ground Reference.
Ground Reference.
An external capacitor on this pin
integrates an error signal which
nulls the offset of the input
amplifier. If the DC feedback loop is
not being used, this pin should be
connected to V
REF
.
A 2.5V reference with respect to
GND.
This input pin sets the link monitor
threshold.
Analog Filtered Ground.
This input pin should be
capacitively coupled to the input
source or to filtered AV
CC
. (The
input resistance is approximately
1.3kΩ.)
This input pin should be
capacitively coupled to the input
source or to filtered AV
CC
. (The
input resistance is approximately
1.3kΩ.)
Analog Filtered +5 volts.
Jabber network status LED. When in
the Jabber state, this pin will be low
and the transmitter will be disabled.
In the Jabber “OK” state this pin will
be high. Active low LED, open
collector.
2
3
COL+
COL–
16
RCV
4
C
TIMER
17
18
19
20
21
V
CC
Tx
TxOUT
GND
GND
V
DC
5
SQEN/JABD SQE Test Enable, Jabber Disable.
When tied low, SQE test is disabled,
when tied high SQE test is enabled.
When tied to 2.0V both SQE test and
Jabber are disabled.
Rx+
Rx–
Manchester encoded receive data
output to the local device. Balanced
differential line driver outputs that
meet AUI specifications.
Loopback Disable. When this pin is
tied to V
CC
, the AUI transmit pair
data is not looped back to the AUI
receive pair, and collision is disabled.
When this pin is tied to GND
(normal operation) or left floating, the
AUI transmit pair data is looped back
to the AUI receiver pair, except
during collision.
+5 volt power input.
Balanced differential line receiver
inputs that meet AUI specifications.
These inputs may be transformer or
capacitively coupled. The Tx input
pins are internally DC biased for AC
coupling.
Sets the current driven output of the
transmitter.
A 1% 61.9kΩ resistor tied from this
pin to V
CC
sets the biasing currents
for internal nodes.
Link Monitor “Low Light” LED status
output. This pin is pulled low when
the voltage on the V
IN
+, V
IN
– inputs
exceed the minimum threshold set by
the V
THADJ
pin, and there are
transitions on V
IN
+, V
IN
– indicating
an idle signal or active data. If either
the voltage on the V
IN
+, V
IN
– inputs
fall below the minimum threshold or
transitions cease on V
IN
+, V
IN
–,
LMON
will go high. Active low LED
driver, open collector.
6
7
8
LBDIS
22
23
24
25
V
REF
V
THADJ
AGND
V
IN
–
9
10
11
V
CC
Tx+
Tx–
26
V
IN
+
12
13
RTSET
RRSET
27
28
AV
CC
JAB
14
LMON
3
MICRO-LINEAR [ MICRO LINEAR CORPORATION ]
