Reference Only / Allayer Confidential
AL211
Preliminary 1.2
Fast Ethernet Fiber to TP Media Converter
Product Description
The AL211 is designed for media converter applications. It is intended for 100 Mbit/s Fast Ethernet
fiber optic to twisted pair media converter designs. The device also provides a PECL interface for
use with media connectors such as 1300nm fiber optic modules. The AL211 is compatible with
IEEE 802.3 100Base-FX and 100Base-TX standards.
The integrated media converter provides additional functionality such as fault propagation and
redundant link support that conventional implementations using discrete components typically can
not support. The AL211 also provides a secondary channel for inband management information
exchange.
The AL211 includes: elastic store, scrambler, and descrambler functions to complete the media
converter design.
.
Figure 1-1
System Block Diagram
Single chip 100 Mbit/s fiber optic to
twisted pair media converter
Low latency
Integrated elastic store for retiming
Supports a secondary channel for manage-
ment
Full duplex capable
Link fault propagation
PECL interface
Supports Auto-negotiation to full
duplex
Remote fault detection capable
Provides support for redundant link
80mA drive capability
Fabricated in CMOS and 48-pin PQFP
package
FIFO
100 Base
TX
Receiver
Clock
Recovery
Elastic
Store
Descrambler
100 Base
TX
Receiver
Scrambler
Elastic
Store
Clock
Recovery
FIFO
Secondary Channel Data Out
Fiber
Receive
Module
Secondary Channel Data In
PECL
Driver
PECL
Receiver
Fiber
Transmit
Module
Reference Only / Allayer Confidential
Table of Contents
1.
Pin Descriptions....................................................................................................... 4
2.
Functional Description............................................................................................. 8
2.1
100Base-TX to 100Base-FX Conversion......................................................... 9
2.2
100Base-FX to 100Base-TX Conversion......................................................... 9
2.3
Secondary Channel .......................................................................................... 9
2.4
Full Duplex Application ................................................................................ 10
2.5
PECL Interface............................................................................................... 10
2.6
Elastic Store ................................................................................................... 10
2.7
Scrambler ....................................................................................................... 11
2.8
Fault Propagation ........................................................................................... 11
2.9
Redundant Link.............................................................................................. 11
2.9.1
Receive Link Fault ................................................................................. 12
2.9.2
Transmit Link Fault................................................................................ 13
2.9.3
Redundant Link with Switches or Repeater........................................... 13
2.10
LED Indicators............................................................................................... 14
3.
Electrical Specifications ........................................................................................ 16
4.
AL211 Mechanical Data ........................................................................................ 18
AL211 Preliminary 1.2
12/99
Reference Only / Allayer Confidential
3
Figure 1-2
AL211 Pin Out
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
AL211
1
2
3
4
5
6
7
8
9
10
11
12
TPI+
TPI-
TPO+
TPO-
Reset#
LED_Rcv_TP
LED_link_TP
LED_Rcv_F
LED_link_F
Redun#
SCRen
ES_TP
off
ES_F
off
DNBIT
TP_PECL
PD
Xin
Xout
Rbias
RLED
Data_off
ENFLP
FI+
FI-
GNDR_F
Reserved
FO+
FO-
FVout
VccT_F
VccR_F
Test1
GNDT_F
Pause
Vcc
GND
MSGCLK
UPBIT
Test3
VccT_TP
GNDR_TP
VccR_TP
Test2
GNDT_TP
VccA
GND
A
Vcc_PLL
Xin
GND_PLL
AL211 Preliminary 1.2
12/99
Reference Only / Allayer Confidential
4
1. Pin Descriptions
Table 1: AL211 Pin Description
PIN
NUMBER
PIN
NAME
I/O
DESCRIPTION
1
GNDR_TP
P
TP Receive Ground.
2
3
TPI+
TPI-
I
100Base-TX Receiver Input Data. During normal operation,
the pins receive MLT3 signals and are connected to a
transformer. When the TPPECL pin is pulled high, these pins
become a PECL level interface. It can then be used for
interfacing to an external equalizer chip for added distance.
4
VccR_TP
P
TP Receive Power Supply.
5
Test2
I
Test Pin. Tied low for normal operation. Tied high to force TP
output enable.
6
GNDT_TP
P
TP Transmit Ground.
7
8
TPO+
TPO-
O
100Base-TX Transmit Data. During normal operation, the
pins transmit MLT3 signals and are connected to a
transformer. When the TPPECL pin is pulled high, these pins
will transmit PECL NRZI signals for interface to an external
equalizer chip.
9
VccT_TP
P
TP Transmit Power Supply.
10
Test3
I
Test Pin. Tied low for normal operation. Tied high to force Fx
output "idle" when TP link is down.
11
UPBIT
I
Secondary Channel Data Input. Internal pull up.
12
MSGCLK
I
Secondary Channel Clock. Internal pull up.
13
Reset#
I
Reset Pin. Active low. Internal pull up.
14
LED_Rcv
_TP
O
TP Receiving Activity Output Status Pin. It will be active low
when the device is receiving frames on the TP side. It is an
open drain driver capable of driving a 10mA LED.
15
Vcc
P
Digital Circuit Power Supply. (+5V)
16
LED_link
_TP
O
TP Link Detect Output Status Pin. It will be low when TP link
is detected. It is capable of driving a 10mA LED.
17
GND
P
Digital Circuit Ground.
18
LED_Rcv_F
O
Fiber Receiving Activity Output Status Pin. It will be active
low when the device is receiving frames on FB site. It is an
output driver capable of driving a 10mA LED.
AL211 Preliminary 1.2
12/99
Reference Only / Allayer Confidential
5
19
LED_link_F
O
Indicates Fiber Link Status. A steady ON LED indicates a
good fiber link. A blinking LED indicates a remote fault
detected. A OFF LED indicates no fiber link detected. It is an
open drain driver capable of driving a 10mA LED.
20
Redun#
O
Redundant Link Output Pin. The pin will be asserted (LOW)
if the device is in either the link-fail state or if it senses a
remote fault condition.
21
SCRen
I
Scrambler Enable for TP Port Output. Active high, internal
pull up.
22
ES_TPoff
I
Elastic Store of TP to Fiber Path Disable. Active high,
internal pull down.
23
ES_Foff
I
Elastic Store of Fiber to TP Path Disable. Active high,
internal pull down.
24
DNBIT
O
Secondary Channel Data Out.
25
Pause
I
Pause Capability Advertisement Enable. Active high, internal
pull up.
26
VccT_F
P
Power Supply. (+5V)
27
Reserved
O
Leave unconnected.
28
29
FO-
FO+
O
PECL output pins for driving the fiber optic module.
30
GNDT_F
P
Fiber Transmit Ground.
31
Reserved
I
Tied high or leave floating.
32
Test1
I
Test Pin. Tied low for normal operation.
33
GNDR_F
P
Fiber Receive Ground.
34
35
FI-
FI+
I
PECL input pins for driving the fiber optic module.
36
VccR_F
P
Fiber Receiver Power Supply. (+5V)
37
ENFLP
I
Enables Full Duplex Auto-negotiation FLP. Active high,
internal pull up.
38
Data_off
I
Assertion of this pin turns off the TP port output. Deassertion
will enable the AL211 to pass data to the TP port. Internal
pull down.
Table 1: AL211 Pin Description (Continued)
PIN
NUMBER
PIN
NAME
I/O
DESCRIPTION
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