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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.
FEATURES
s
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.
s
s s s
* This Part Is End Of Life As Of August 1, 2000
BLOCK DIAGRAM
67 55 56 21 20 54 53 64 10 7 24 23 2 1 31 12 11 34 33 5 4 32 46 47 37 36 59 58 44 66 61 17 25
TxIN1N TxIN1P RxOUT1N RxOUT1P CDOUT1N CDOUT1P SQEN1 TxIN2N TxIN2P RxOUT2N RxOUT2P CDOUT2N CDOUT2P SQEN2 TxIN3N TxIN3P RxOUT3N RxOUT3P CDOUT3N CDOUT3P SQEN3 TxIN4N TxIN4P RxOUT4N RxOUT4P CDOUT4N CDOUT4P SQEN4
22 3 51
X2 X1 MAU AUI INTERFACE
X3
RRESET BIASING
VCC
26
VCC
OSCILLATOR
MAU AUI INTERFACE TxOUTP TxOUTN MUX DTE AUI INTERFACE RxINP RxINN CDINP CDINN
15 14 29 30 63 60
MAU AUI INTERFACE
MAU AUI INTERFACE
LED DRIVERS
COLL
JAB1
JAB2
JAB3
JAB4
GND
41
REC
Tx1
Tx2
Tx3
49
50
Tx4
48
45
19
39
52
1
ML4644
PIN CONNECTIONS
CDOUT3N CDOUT2N CDOUT3P CDOUT2P TxIN2P SQEN1 CDINP COLL NC NC NC NC NC NC X2 X1 X3
60 CDINN 59 CDOUT4N 58 CDOUT4P 57 NC 56 TxIN1P 55 TxIN1N 54 CDOUT1N 53 CDOUT1P 52 GND 51 Tx1 50 Tx2 49 Tx3 48 Tx4 47 TxIN4P 46 TxIN4N 45 JAB1 44 SQEN4 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43
9
8
7
6
5
4
3
2
1
68 67 66 65 64 63 62 61
TxIN2N 10 TxIN3P 11 TxIN3N 12 NC 13 TxOUTN 14 TxOUTP 15 RESERVED 16 RRSET 17 NC 18 JAB2 19 RxOUT1P 20 RxOUT1N 21 REC 22 RxOUT2P 23 RxOUT2N 24 VCC 25 VCC 26
ML4644
RxINN
NC
NC
RxINP
SQEN2
SQEN3
RxOUT3P
RxOUT3N
NC
RxOUT4P
RxOUT4N
NC
NC
NC
JAB3
PIN DESCRIPTION
PIN #
1
NAME
CDOUT2P CDOUT2N
FUNC.
Output Output
DESCRIPTION Collision signal pair for DTE port 2. Collision signal pair for DTE port 2. Open collector LED driver for collision. Collision signal pair for DTE port 3. Collision signal pair for DTE port 3. No connection.
PIN # 13 14 15 16 17
NAME NC TxOUTN TxOUTP Reserved RRSET
JAB4
NC
FUNC.
DESCRIPTION No connection.
Output Output
2 3 4 5 6 7 8 9 10 11 12
Transmit signal pair for MAU port. Transmit signal pair for MAU port. This pin should be tied to VCC.
COLL
CDOUT3P CDOUT3N
Output
Output Output
Input
Bias setting external resistor, 61.9ky, connected to VCC No connection. Open collector jabber LED driver for Jabber of DTE port 2. Receive signal pair for DTE port 1. Receive signal pair for DTE port 1. Open collector LED driver for receive. Grounding this pin enables loopback.
NC TxIN2P NC NC TxIN2N TxIN3P TxIN3N Input Input Input Input
18 19
NC JAB2 Output
Transmit signal pair for DTE port 2. No connection. No connection. Transmit signal pair for DTE port 2. Transmit signal pair for DTE port 3. Transmit signal pair for DTE port 3.
20 21 22
RxOUT1P
Output
RxOUT1N Output REC Output
2
ML4644
PIN DESCRIPTION (Continued)
PIN # 23 24 25 26 27 28 29 30 31 NAME RxOUT2P FUNC. Output DESCRIPTION Receive signal pair for DTE port 2. Receive signal pair for DTE port 2. +5V power supply. +5V power supply. No connection. No connection. Input Input Input Receive signal pair for MAU port. Receive signal pair for MAU port. Active low. This pin is used to enable the SQE function of DTE port 2. Active low. This pin is used to enable the SQE function of DTE port 3. Receive signal pair for DTE port 3. Receive signal pair for DTE port 3. No connection. Output Receive signal pair for DTE port 4. Receive signal pair for DTE port 4. No connection. Output Open collector jabber LED driver for Jabber of DTE port 3. No connection. Output Open collector jabber LED driver for Jabber of DTE port 4. No connection. No connection. Input Active low. This pin is used to enable the SQE function of DTE port 4. Open collector jabber LED driver for Jabber of DTE port 1. Transmit signal pair for DTE port 4. Transmit signal pair for DTE port 4. 67 68 X2 NC Input 65 66 NC X1 Input 59 60 61
CDOUT4N Output
PIN # 48
NAME Tx4
FUNC. Output
DESCRIPTION Open collector transmit LED driver for Jabber of DTE port 4. Open collector transmit LED driver for Jabber of DTE port 3. Open collector transmit LED driver for Jabber of DTE port 2. Open collector transmit LED driver for Jabber of DTE port 1. Ground. Collision signal pair for DTE port 1. Collision signal pair for DTE port 1. Transmit signal pair for DTE port 1. Transmit signal pair for DTE port 1. No connection. Collision signal pair for DTE port 4. Collision signal pair for DTE port 4. Collision signal pair for MAU port. ECL output driven by crystal. Can drive X1 inputs on other ML4644S. No connection. Collision signal pair for MAU port. Active low. This pin is used to enable the SQE function of DTE port 1. No connection. 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. 10 MHz Crystal input pin. No connection.
RxOUT2N Output VCC VCC NC NC RxINP RxINN SQEN2 Power Power
49
Tx3
Output
50
Tx2
Output
51
Tx1
Output
52 53 54 55 56 57 58
GND
CDOUT1P CDOUT1N
Ground
Output Output
32
SQEN3
Input
TxIN1N TxIN1P NC
CDOUT4P
Input Input
33 34 35 36 37 38 39
RxOUT3P
Output
RxOUT3N Output NC RxOUT4P
Output
RxOUT4N Output NC JAB3
CDINN X3
Input Output
40 41
NC JAB4
62 63 64
NC CDINP SQEN1 Input Input
42 43 44
NC NC SQEN4
45
JAB1
Output
46 47
TxIN4N TxIN4P
Input Input
3
ML4644
ABSOLUTE MAXIMUM RATINGS
Absolute maximum ratings are limits beyond which the life of the integrated circuit may be impaired. All voltages 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 . . . . . . . . . . . . . . . . . . . . . . 150C Storage Temperature . . . . . . . . . . . . . . . . -65C to 150C Lead Temperature (Soldering 10 seconds) . . . . . . . 260C Thermal Resistance (qJA) . . . . . . . . . . . . . . . . . . . 44C/W
OPERATING CONDITIONS
Supply Voltage (VCC) . . . . . . . . . . . . . . . . . . . 5V 10% RRSET . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61.9ky 1%
ELECTRICAL CHARACTERISTICS
Unless otherwise specified TA = 0C to 70C, VCC = 5V 10%. (Notes 1, 2)
PARAMETER Power Supply Current ICC (Note 3) LED Drivers: VOL Transmit Squelch Voltage Level (Tx+, Tx-) Differential Output Voltage Common Mode Output Voltage Differential Output Voltage Imbalance Loopback Enable
Note 1: Note 2: Note 3:
CONDITIONS VCC = 5V RL=510y (Note 4)
MIN 50
TYP. 150
MAX 190 0.8
UNITS mA V mV mV V
-300 550
-250
-200 1200
4.0 2 REC tied low 40 0.3
mV V
Limits are guaranteed by 100% testing , sampling, or correlation with worst-case test conditions. Low Duty cycle pulse testing is performed at TA. This does not include the current from the AUI pull down resistors or the LED output pins.
4
ML4644
AC ELECTRICAL CHARACTERISTICS
SYMBOLS TRANSMIT tXODY tTXSDY tTXFPW tTXSOI RECEIVE tRXODY tRXSDY tRXFPW tRXSOI tAR tAF COLLISION tCPSQE tSQEXR FCLF Collision Present to SQE Assert Time for SQE to Deactivate After a Collision Collision Frequency Collision Pulse Duty Cycle FJAM tSQEDY tSQETD JAM Frequency at TxOUT SQE Test Delay (Tx Inactive to SQE) SQE Test Duration XTAL Controlled XTAL Controlled XTAL Controlled 0.6 0.5 0 0 8.5 40 10 50 5 1.1 1.0 1.6 1.5 200 500 11.5 60 ns ns MHz % MHz s s Receive Turn-On Delay Receive Steady State Prop. Delay Receive Turn-Off Pulse Width Receive Turn-Off Start of Idle Differential Output Rise Time 20% to 80% (Rx, COL, TxOUT) Differential Output Fall Time 20% to 80% (Rx, COL, TxOUT) 200 100 15 180 250 3 3 200 ns ns ns ns ns ns Transmitter Turn-On Delay Transmit Steady State Prop. Delay Transmit Turn-Off Pulse Width Transmit Turn-Off Start of Idle 200 100 15 180 250 200 ns ns ns ns PARAMETER MIN TYP. MAX UNITS
JABBER, LINK TEST AND LED TIMING tJAD tJSQE tLEDT Jabber Activation Delay Delay from Outputs Disabled to Collision Oscillator On REC, COLL, Tx1, Tx2, Tx3, Tx4 On Time 0.3 7 13.5 100 1.0 3.0 20 ms ns ms
5
ML4644
TIMING DIAGRAMS
TxINP VALID TxINN tTxODY TxOUTP VALID TxOUTN tTxLP RxOUTP RxOUTN tTxSDY tAR DATA tAF tTxFPW tXSOI DATA
Figure 3. Transmit Timing
tRXFPN RxINP VALID RxINN tRXODY DATA tRXSDY tAR RxOUT1, 2, P RxOUT1, 2, N VALID DATA tAF tRXSOI
Figure 4. Receive Timing
TxIN2P TxIN2N VALID DATA
TxIN1P TxIN1N tCPSQE CDOUT1, 2, P CDOUT1, 2, N
VALID
DATA
FCLK CS0
FJAM TxOUTP TxIN2 TxOUTN TxIN2 TxIN2 JAM JAM
Figure 5. Collision Timing
6
ML4644
TIMING DIAGRAMS (Continued)
TxIN1P TxIN1N
TxIN2P VALID TxIN2N tSQEXR CDOUT1, 2, P CS0 CDOUT1, 2, N DATA
TxOUTP TxOUTN JAM JAM
tXIN2P
tXIN2P
Figure 6. Collision Timing
TxIN1P TxIN1N
VALID DATA tSQETD tSQETDY
CDOUT1P CDOUT1N
CS0
CDOUT2P CDOUT2N
Figure 7. SQE Timing
TxIN1P TxIN1N
VALID tJAD
DATA
TxOUT1P TxOUT1N
VALID DATA
tJSQE CDOUT1P CDOUT1N
Figure 8. Jabber Timing
7
ML4644
TxOUT1P TxOUT1N tLETD TxLED1
Figure 9. LED Timing
8
ML4644
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. 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. 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 1s. 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.
ML4644
ML4642
ML4644
Figure 2. Block Diagram of an Eight port Multiplexer.
9
ML4644
TxIN1P TxIN1N 39 39 0.1F RxOUT1P RTSET RxOUT1N 360 360 CDOUT1P CDOUT1N 360 360 TxIN2P TxIN2N RxINP RxINN 39 39 TxOUTP TxOUTN 360 360 61.9K +5V VCC VCC 0.1 .01 +5V
RxOUT2P RxOUT2N
CDINP CDINN 39 39
CDOUT2P CDOUT2N SQEN1 VCC
ML4644
TxIN3P TxIN3N
SQEN2 SQEN3 SQEN4 RESERVED X1
RxOUT3P RxOUT3N X2
10pF
10MHz 5pF 5pF
X3 CDOUT3P CDOUT3N JAB1 JAB2 TxIN4P TxIN4N JAB3 510 JAB4 510 Tx1 Tx2 RxOUT4P Tx3 RxOUT4N Tx4 CDOUT4P CDOUT4N COLL REC 510 270 510 510 510 510 510 +5V +5V +5V +5V +5V +5V +5V +5V
510
+5V +5V
Figure 1. Four Port AUI Multiplexer.
10
ML4644
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 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
PIN 1 ID
52
0.950 - 0.956 0.985 - 0.995 (24.13 - 24.28) (25.02 - 25.27)
0.800 BSC (20.32 BSC)
0.890 - 0.930 (22.61 - 23.62)
35 0.050 BSC (1.27 BSC) 0.026 - 0.032 (0.66 - 0.81) 0.165 - 0.180 (4.06 - 4.57) 0.146 - 0.154 (3.71 - 3.91) 0.007 - 0.008 (0.18 - 0.20) 0.095 - 0.118 (2.41 - 3.00)
0.013 - 0.021 (0.33 - 0.53)
SEATING PLANE
ORDERING INFORMATION
PART NUMBER ML4644CQ (EOL) TEMPERATURE RANGE 0C to 70C PACKAGE 68-Pin PLCC (Q68)
(c) 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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