Page 1
April 1997
ML4644*
4 Port AUI Multiplexer
GENERAL DESCRIPTION
The ML4644 AUI Multiplexer contains all the necessary
drivers/receivers and control logic to implement a 4 port
MAU when used in conjuction with a transceiver chip
which has a standard 802.3 AUI interface. Several
ML4644s can be cascaded together to implement an 8 or
12 port MAU or standalone device.
Logic within the ML4644 detects collisions resulting from
multiple DTEs transmitting simultaneously. In addition,
collision signals received from a transceiver attached at
the MAU port are propagated to all of the DTE ports.
Jabbering DTEs are prevented from loading down the
network by an internal jabber timer which disables
babbling ports.
BLOCK DIAGRAM
TxIN1N
55
TxIN1P
56
RxOUT1N
21
RxOUT1P
20
CDOUT1N
54
CDOUT1P
53
SQEN1
64
TxIN2N
10
TxIN2P
7
RxOUT2N
24
RxOUT2P
23
CDOUT2N
2
CDOUT2P
1
SQEN2
31
TxIN3N
12
TxIN3P
11
RxOUT3N
34
RxOUT3P
33
CDOUT3N
5
CDOUT3P
4
SQEN3
32
TxIN4N
46
TxIN4P
47
RxOUT4N
37
RxOUT4P
36
CDOUT4N
59
CDOUT4P
58
SQEN4
44
MAU
AUI
INTERFACE
MAU
AUI
INTERFACE
MAU
AUI
INTERFACE
MAU
AUI
INTERFACE
REC
COLL
FEATURES
■ IEEE 802.3 compliant AUI interfaces assure
compatibility with any AUI ready devices.
■ On-chip Jabber logic, Collision Detection,
and SQE test with enable/disable option.
■ Selectable SQE Test
■ Selectable loopback
■ Ten network status LED outputs.
* This Part Is End Of Life As Of August 1, 2000
6667
X2 X1
OSCILLATOR
MUX
Tx1
Tx2
61
X3
LED DRIVERS
Tx3
17 25 26
R
RESET
BIASING
INTERFACE
Tx4
JAB1
JAB2
DTE
AUI
JAB3
VCC
JAB4
VCC
TxOUTP
TxOUTN
RxINP
RxINN
CDINP
CDINN
GND
524139194548495051322
15
14
29
30
63
60
1
Page 2
ML4644
PIN CONNECTIONS
TxIN2N
TxIN3P
TxIN3N
NC
TxOUTN
TxOUTP
RESERVED
RRSET
NC
JAB2
RxOUT1P
RxOUT1N
REC
RxOUT2P
RxOUT2N
VCC
VCC
NCNCTxIN2PNCCDOUT3N
987 65
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27 28 29 30 31
NC
NC
RxINP
CDOUT3P
COLL
43342351366837673866
ML4644
32 33
RxINN
SQEN2
SQEN3
RxOUT3P
CDOUT2N
CDOUT2PNCX2X1NC
NC
RxOUT4P
RxOUT3N
RxOUT4N
SQEN1
CDINPNCX3
65 64 63 62 61
39 40 41 42 43
NC
JAB3NCJAB4
NC
NC
CDINN
60
CDOUT4N
59
CDOUT4P
58
NC
57
TxIN1P
56
TxIN1N
55
CDOUT1N
54
53
CDOUT1P
52
GND
51
Tx1
50
Tx2
49
Tx3
48
Tx4
47
TxIN4P
46
TxIN4N
45
JAB1
44
SQEN4
PIN DESCRIPTION
PIN # NAME FUNC. DESCRIPTION
1 CDOUT2P Output Collision signal pair for
DTE port 2.
2 CDOUT2N Output Collision signal pair for
DTE port 2.
3 COLL Output Open collector LED
driver for collision.
4 CDOUT3P Output Collision signal pair for
DTE port 3.
5 CDOUT3N Output Collision signal pair for
DTE port 3.
6 NC No connection.
7 TxIN2P Input Transmit signal pair for
DTE port 2.
8 NC No connection.
9 NC No connection.
10 TxIN2N Input Transmit signal pair for
DTE port 2.
11 TxIN3P Input Transmit signal pair for
DTE port 3.
12 TxIN3N Input Transmit signal pair for
DTE port 3.
PIN # NAME FUNC. DESCRIPTION
13 NC No connection.
14 TxOUTN Output Transmit signal pair for
MAU port.
15 TxOUTP Output Transmit signal pair for
MAU port.
16 Reserved This pin should be tied
to VCC.
17 RRSET Input Bias setting external
resistor, 61.9ký,
connected to VCC
18 NC No connection.
19 JAB2 Output Open collector jabber
LED driver for Jabber of
DTE port 2.
20 RxOUT1P Output Receive signal pair for
DTE port 1.
21 RxOUT1N Output Receive signal pair for
DTE port 1.
22 REC Output Open collector LED
driver for receive.
Grounding this pin
enables loopback.
2
Page 3
PIN DESCRIPTION (Continued)
ML4644
PIN # NAME FUNC. DESCRIPTION
23 RxOUT2P Output Receive signal pair for
DTE port 2.
24 RxOUT2N Output Receive signal pair for
DTE port 2.
25 VCC Power +5V power supply.
26 VCC Power +5V power supply.
27 NC No connection.
28 NC No connection.
29 RxINP Input Receive signal pair for
MAU port.
30 RxINN Input Receive signal pair for
MAU port.
31 SQEN2 Input Active low. This pin is
used to enable the SQE
function of DTE port 2.
32 SQEN3 Input Active low. This pin is
used to enable the SQE
function of DTE port 3.
33 RxOUT3P Output Receive signal pair for
DTE port 3.
34 RxOUT3N Output Receive signal pair for
DTE port 3.
35 NC No connection.
36 RxOUT4P Output Receive signal pair for
DTE port 4.
37 RxOUT4N Output Receive signal pair for
DTE port 4.
38 NC No connection.
39 JAB3 Output Open collector jabber
LED driver for Jabber of
DTE port 3.
40 NC No connection.
41 JAB4 Output Open collector jabber
LED driver for Jabber of
DTE port 4.
42 NC No connection.
43 NC No connection.
44 SQEN4 Input Active low. This pin is
used to enable the SQE
function of DTE port 4.
45 JAB1 Output Open collector jabber
LED driver for Jabber of
DTE port 1.
46 TxIN4N Input Transmit signal pair for
DTE port 4.
47 TxIN4P Input Transmit signal pair for
DTE port 4.
PIN # NAME FUNC. DESCRIPTION
48 Tx4 Output Open collector transmit
LED driver for Jabber of
DTE port 4.
49 Tx3 Output Open collector transmit
LED driver for Jabber of
DTE port 3.
50 Tx2 Output Open collector transmit
LED driver for Jabber of
DTE port 2.
51 Tx1 Output Open collector transmit
LED driver for Jabber of
DTE port 1.
52 GND Ground Ground.
53 CDOUT1P Output Collision signal pair for
DTE port 1.
54 CDOUT1N Output Collision signal pair for
DTE port 1.
55 TxIN1N Input Transmit signal pair for
DTE port 1.
56 TxIN1P Input Transmit signal pair for
DTE port 1.
57 NC No connection.
58 CDOUT4P Output Collision signal pair for
DTE port 4.
59 CDOUT4N Output Collision signal pair for
DTE port 4.
60 CDINN Input Collision signal pair for
MAU port.
61 X3 Output ECL output driven by
crystal. Can drive X1
inputs on other
ML4644S.
62 NC No connection.
63 CDINP Input Collision signal pair for
MAU port.
64 SQEN1 Input Active low. This pin is
used to enable the SQE
function of DTE port 1.
65 NC No connection.
66 X1 Input 10MHz Crystal input pin.
This pin can also be used
as a 10MHz clock input
pin, or can connect to X3
of another that is driven
by a crystal or 10MHz
clock.
67 X2 Input 10 MHz Crystal input pin.
68 NC No connection.
3
Page 4
ML4644
ABSOLUTE MAXIMUM RATINGS
Absolute maximum ratings are limits beyond which the
life of the integrated circuit may be impaired. All voltages
OPERATING CONDITIONS
Supply Voltage (VCC) . . . . . . . . . . . . . . . . . . . 5V ± 10%
RRSET . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61.9ký ± 1%
unless otherwise specified are measured with respect to
ground.
Power Supply Voltage Range VCC. . . GND –0.3 to +6.0V
Input Current RRSET, All LED Driver Pins . . . . . . . 60mA
Junction Temperature . . . . . . . . . . . . . . . . . . . . . . 150°C
Storage Temperature . . . . . . . . . . . . . . . . –65°C to 150°C
Lead Temperature (Soldering 10 seconds) . . . . . . . 260°C
Thermal Resistance (qJA) . . . . . . . . . . . . . . . . . . . 44°C/W
ELECTRICAL CHARACTERISTICS
Unless otherwise specified TA = 0°C to 70°C, VCC = 5V ± 10%. (Notes 1, 2)
PARAMETER CONDITIONS MIN TYP. MAX UNITS
Power Supply Current ICC (Note 3) V
LED Drivers: V
Transmit Squelch Voltage Level (Tx+, Tx–) –300 –250 –200 mV
Differential Output Voltage ±550 ±1200 mV
Common Mode Output Voltage 4.0 V
OL
= 5V 50 150 190 mA
CC
RL=510ý (Note 4) 0.8 V
Differential Output Voltage Imbalance 2 ±40 mV
Loopback Enable REC tied low 0.3 V
Note 1: Limits are guaranteed by 100% testing , sampling, or correlation with worst-case test conditions.
Note 2: Low Duty cycle pulse testing is performed at T
Note 3: This does not include the current from the AUI pull down resistors or the LED output pins.
.
A
4
Page 5
ML4644
AC ELECTRICAL CHARACTERISTICS
SYMBOLS PARAMETER MIN TYP. MAX UNITS
TRANSMIT
t
XODY
t
TXSDY
t
TXFPW
t
TXSOI
RECEIVE
t
RXODY
t
RXSDY
t
RXFPW
t
RXSOI
t
AR
t
AF
COLLISION
t
CPSQE
t
SQEXR
Transmitter Turn-On Delay 100 200 ns
Transmit Steady State Prop. Delay 15 ns
Transmit Turn-Off Pulse Width 180 ns
Transmit Turn-Off Start of Idle 200 250 ns
Receive Turn-On Delay 100 200 ns
Receive Steady State Prop. Delay 15 ns
Receive Turn-Off Pulse Width 180 ns
Receive Turn-Off Start of Idle 200 250 ns
Differential Output Rise Time 3 ns
20% to 80% (Rx±, COL±, TxOUT±)
Differential Output Fall Time 3 ns
20% to 80% (Rx±, COL±, TxOUT±)
Collision Present to SQE Assert 0 200 ns
Time for SQE to Deactivate After a Collision 0 500 ns
F
CLF
Collision Frequency XTAL Controlled 8.5 10 11.5 MHz
Collision Pulse Duty Cycle XTAL Controlled 40 50 60 %
F
JAM
t
SQEDY
t
SQETD
JAM Frequency at TxOUT± XTAL Controlled 5 MHz
SQE Test Delay (Tx Inactive to SQE) 0.6 1.1 1.6 µs
SQE Test Duration 0.5 1.0 1.5 µs
JABBER, LINK TEST AND LED TIMING
t
JAD
t
JSQE
t
LEDT
Jabber Activation Delay 7 13.5 20 ms
Delay from Outputs Disabled to Collision Oscillator On 100 ns
REC, COLL, Tx1, Tx2, Tx3, Tx4 On Time 0.3 1.0 3.0 ms
5
Page 6
ML4644
TIMING DIAGRAMS
TxINP
TxINN
TxOUTP
TxOUTN
RxOUTP
RxOUTN
RxINP
RxINN
RxOUT1, 2, P
RxOUT1, 2, N
VALID DATA
t
TxODY
t
TxLP
t
TxSDY
Figure 3. Transmit Timing
VALID DATA
t
RXODY
t
RXSDY
t
TxFPW
t
AR
DATAVALID
t
AR
DATAVALID
t
AF
t
RXFPN
t
AF
t
RXSOI
t
XSOI
TxIN2P
TxIN2N
TxIN1P
TxIN1N
CDOUT1, 2, P
CDOUT1, 2, N
TxOUTP
TxOUTN
Figure 4. Receive Timing
VALID DATA
VALID DATA
t
CPSQE
CS0
TxIN2 TxIN2 TxIN2 JAMJAM
F
CLK
F
JAM
Figure 5. Collision Timing
6
Page 7
TIMING DIAGRAMS (Continued)
TxIN1P
TxIN1N
ML4644
TxIN2P
TxIN2N
CDOUT1, 2, P
CDOUT1, 2, N
TxOUTP
TxOUTN
JAM JAM
TxIN1P
TxIN1N
CDOUT1P
VALID DATA
t
SQEXR
CS0
VALID DATA
t
XIN2P
t
XIN2P
Figure 6. Collision Timing
t
SQETDY
t
SQETD
CS0
CDOUT1N
CDOUT2P
CDOUT2N
TxIN1P
TxIN1N
TxOUT1P
TxOUT1N
CDOUT1P
CDOUT1N
Figure 7. SQE Timing
VALID DATA
t
JAD
VALID
DATA
t
JSQE
Figure 8. Jabber Timing
7
Page 8
ML4644
TxOUT1P
TxOUT1N
TxLED1
t
LETD
Figure 9. LED Timing
8
Page 9
ML4644
ML4644
ML4644
ML4642
FUNCTIONAL DESCRIPTION
Figure 1 is a block diagram of a Four Port Multiplexer
using the ML4644. All AUI interfaces are transformer
coupled as required in an AUI connection.
RECEPTION
The receive function consists of detecting data on receive
differential data input pair of the MAU port (RxIN) and
transmitting this data out of the RxOUT ports of all the DTE
port. This data will only be passed onto the DTE port if it
meets the unsquelch criteria of the AUI receiver circuit. This
provision prevents any noise on the AUI cable from being
misinterpreted as data and transmitted to the RxOUT pins.
The receiver squelch circuit rejects signal typically with
pulse width less than 20ns or a voltage level more positive
than –250mV. Once the receiver is unsquelched, it
remains so until reception of the idle signal which is more
positive than –170mV for longer than 180ns.
TRANSMISSION
The transmit function consists of detecting data on any of
the four differential data input pairs (TxIN1, TxIN2, TxIN3,
and TxIN4) and transmitting this data out of the TxOUT
pair of the MAU port.
Only data that meets the unsquelch criteria of the AUI
receiver circuit will be passed onto the TxOUT port.
LOOPBACK
If the ML4644 is connected to a MAU, or connected to
other 4642/44s that are connected to a MAU, the MAU
should be used to provide loopback. The loopback function
of the MAU will loop data back to the RxIN port which will
pass is to all FxOUTs and the REC pin will go low. In some
configurations, there will be no MAU, and a ML4644 will
be the last chip in the Tx path. In this case, the RxIN port
will never be active, since it is not connected, and the REC
pin has no function. The REC pin may be grounded and this
will put the ML4644 in loopback mode, and data on the
TxIN pair will be looped back to all RxOUT ports.
COLLISION
There are two possible collision scenarios.
SQE TEST FUNCTION
The Signal Quality Error (SQE) test function allows the
DTE to determine whether or not the collision port is
functional. After each transmission, during the interpacket
gap time, the collision signal will be activated on the
CDOUT port of the same DTE port data has been
transmitted, for typically 1µs. The SQE function is not
activated at the DTE ports that are in jabber state. The SQE
function of each port can be disabled by tying the SQEN
pin high.
JABBER FUNCTION
The jabber function prevents a malfunction transmitter
from continuous transmission and thus loaded down the
network. Within the ML4644, there is a jabber timer. The
timer starts at the beginning of a received packet and
resets at the end of each packet. If the packet lasts longer
than 7 to 20ms the jabber circuit will disable the
offending TxIN receiver (the transmission of excessively
long packet is thus terminated) and generates a collision
signal to the collision port of the offending DTE port. The
DTE port will exit the jabber state when the transmission
goes idle.
LED DRIVERS
The ML4644 has ten LED drivers. Each DTE port has a
transmit LED and a jabber LED and the MAU port has a
receive LED. Additionally there is a collision LED which
indicates the presence of a collision condition. All LED
drivers are active low open collector driver.
All LED drivers except the jabber have pulse 1ms pulse
stretchers. The pulse stretchers provide adequate on time
for the LED to be visible.
CASCADING THE ML4644 FOR EIGHT PORT
MULTIPLEXER APPLICATION
An 8 port multiplexer can be realized by using two
ML4644s and one ML4642. In this configuration (see fig.
2), the SQE function of the ML4642 should be disabled to
prevent false collision signalling. The SQE function in this
configuration is performed by each DTE port of the
ML4644 independently. Only one crystal is required,
since X3 of the ML4644 with the crystal can drive X1 of
the other chip.
1. Collision from the network connected to the MAU.
2. Collision between two or more DTEs attached to the
multiplexer.
In the case of a network collision, the MAU will send a
collision presence signal to the multiplexer. The ML4644
will propagate this signal to the CDOUT pins of each of the
DTE ports. The collision signal is a 10MHz ±0.01% signal.
When a collision event occurs between two or more DTE
ports, the ML4644 will send the collision presence signal to
each of the DTEs via the collision ports. At the same time a
5MHz JAM signal is sent to the network.
Figure 2. Block Diagram of an Eight port Multiplexer.
9
Page 10
ML4644
39
360Ω 360Ω
360Ω 360Ω
39
0.1µF
TxIN1P
TxIN1N
RxOUT1P
RxOUT1N
CDOUT1P
CDOUT1N
TxIN2P
TxIN2N
RxOUT2P
RxOUT2N
V
CC
V
CC
RTSET
TxOUTP
TxOUTN
RxINP
RxINN
CDINP
CDINN
61.9K
+5V
0.1
360Ω360Ω
3939
3939
.01
+5V
CDOUT2P
CDOUT2N
TxIN3P
TxIN3N
RxOUT3P
RxOUT3N
CDOUT3P
CDOUT3N
TxIN4P
TxIN4N
RxOUT4P
RxOUT4N
CDOUT4P
CDOUT4N
ML4644
SQEN1
SQEN2
SQEN3
SQEN4
RESERVED
X1
X2
X3
JAB1
JAB2
JAB3
JAB4
Tx1
Tx2
Tx3
Tx4
COLL
REC
10pF
510
510
510
510
510
510
510
510
510
270
10MHz
5pF
V
+5V
+5V
+5V
+5V
+5V
+5V
+5V
+5V
+5V
+5V
CC
5pF
10
Figure 1. Four Port AUI Multiplexer.
Page 11
PHYSICAL DIMENSIONS inches (millimeters)
Package: Q68
68-Pin PLCC
0.985 - 0.995
(25.02 - 25.27)
0.950 - 0.956
(24.13 - 24.28)
1
ML4644
0.042 - 0.056
(1.07 - 1.42)
0.025 - 0.045
(0.63 - 1.14)
(RADIUS)
0.042 - 0.048
(1.07 - 1.22)
18
0.050 BSC
(1.27 BSC)
0.013 - 0.021
(0.33 - 0.53)
PIN 1 ID
35
0.026 - 0.032
(0.66 - 0.81)
52
0.165 - 0.180
(4.06 - 4.57)
SEATING PLANE
0.950 - 0.956
(24.13 - 24.28)
0.985 - 0.995
(25.02 - 25.27)
0.146 - 0.154
(3.71 - 3.91)
0.007 - 0.008
(0.18 - 0.20)
0.095 - 0.118
(2.41 - 3.00)
0.800 BSC
(20.32 BSC)
0.890 - 0.930
(22.61 - 23.62)
ORDERING INFORMATION
PART NUMBER TEMPERATURE RANGE PACKAGE
ML4644CQ (EOL) 0°C to 70°C 68-Pin PLCC (Q68)
© Micro Linear 1997 is a registered trademark of Micro Linear Corporation
Products described in this document may be covered by one or more of the following patents, U.S.: 4,897,611; 4,964,026; 5,027,116; 5,281,862; 5,283,483; 5,418,502; 5,508,570; 5,510,727; 5,523,940; 5,546,017;
5,559,470; 5,565,761; 5,592,128; 5,594,376; Japan: 2598946; 2619299. Other patents are pending.
Micro Linear reserves the right to make changes to any product herein to improve reliability, function or
design. Micro Linear does not assume any liability arising out of the application or use of any product
described herein, neither does it convey any license under its patent right nor the rights of others. The
circuits contained in this data sheet are offered as possible applications only. Micro Linear makes no
warranties or representations as to whether the illustrated circuits infringe any intellectual property rights of
others, and will accept no responsibility or liability for use of any application herein. The customer is urged
to consult with appropriate legal counsel before deciding on a particular application.
2092 Concourse Drive
San Jose, CA 95131
Tel: 408/433-5200
Fax: 408/432-0295
DS4644-01
11
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