OC-48/STM-16 Receiver without Clock
Recovery
SRX48 Seris
Product Description
The SRX48 modules are receivers designed to meet or exceed the SO-
NET/SDH optical interface requirements at OC-48/STM-16 (2.488 Gb/s)
data rate. Three performance versions are available which are fully com-
pliant with Short Reach, Intermediate Reach and Long Reach specifica-
tions at 1300 nm or 1550 nm wavelength.
The receiver for the Short Reach and Intermediate Reach version uses
PIN photodiodes. For the Long Reach version, InGaAs avalanche pho-
todiodes (APDs) are used to achieve high sensitivity. The Long Reach
receiver features a low noise GaAs transimpedance IC with AGC capa-
bility to provide an extremely wide dynamic range. The DATA outputs
are differential signals designed to be AC-coupled into 50 ohm load. A
TTL Signal Detect function which indicates loss of optical input and an
analog Received Optical Power Monitor output are also provided.
All receiver modules can be operated with a single +5V supply. The op-
erating temperature range is -40°C to +85°C for the Short Reach and In-
termediate Reach version and 0°C to +70°C for the Long Reach version.
All receivers are housed in a 24-pin dual-in-line metal package with a
fiber pigtail (single mode fiber for Long Reach version and 50/125 μm
multimode fiber for Short Reach and Intermediate Reach versions),
which is terminated with MU, LC, ST, FC or SC connector.
Features
Fully compliant with SONET/SDH OC-48 (2.5
Gb/s) specifications
Long Reach 1310 nm & 1550 nm as well as
Intermediate Reach and Short Reach
Internal temperature-compensated High
Voltage APD Supply (Long Reach version)
-40°C to +85°C Operating Temperature
(Intermediate Reach and Short Reach)
24-pin DIP metal package
MU, LC, FC, ST, SC-connectorized fiber pigtails
Differential DATA interface
Received Optical Power Monitor function
TTL SIGNAL DETECT output
Single +5 V supply
Absolute Maximum Ratings
Parameter
Storage Temperature
Operating Case Temperature
“I” option (“SR” & “IR” only)
“H” option
Symbol
T
ST
T
OP
P
in, max
V
CC
V
IN
-
Minimum
- 40
- 40
0
-
0
0
-
Maximum
+ 85
+ 85
+ 70
- 5.0
+ 6.0
V
CC
260°C, 10 sec
Units
°C
°C
dBm
V
V
Maximum Optical Input Power (“LR” only)
Supply Voltage
Input Voltage
Lead Soldering Temperature & Time
An Oplink Company
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SRX48
Receiver Performance Characteristics
Parameter
Data Rate
Receiver Sensitivity
(10
-10
BER)
1
Maximum Input Optical
Power (10
-10
BER)
1
Short & Intermediate Reach
Long Reach
Short Reach (SR)
Intermediate Reach (IR)
Long Reach (LR)
(Over Operating Case Temperature.)
Symbol
B
P
min
Minimum
0.1
- 20.0
- 28.0
- 3.0
P
max
P
sd+
P
sd-
P
sd+
P
sd-
-
V
PM
I
PM
λ
0
- 8.0
-
- 35.0
-
- 42.0
0.5
-
-
1100
Typical
2.488
- 24.0
- 32.0
- 1.0
2.0
-
-
-
-
-
1.0
6.4
0.8
-
Maximum
3.0
-
-
-
-
- 6.0
- 20.0
-
- 28.0
-
-
-
-
1600
dBm
dBm
dB
mV/µW
µA/µW
nm
dBm
Units
Gb/s
dBm
SR & IR
Signal Detect Thresholds
LR
Signal Detect Hysteresis
Optical Power
Monitor
Wavelength of Operation
1
Increasing Light Input
Decreasing Light Input
Increasing Light Input
Decreasing Light Input
LR (P
in
from -28 dBm to -17 dBm)
IR & SR (P
in
from -20 dBm to 0 dBm)
Specified in Average Optical Input Power and measured at 2.48832 Gb/s and 1300 nm or 1550 nm wavelength with 2
23
-1 PRBS.
Receiver Electrical Interface
Parameter
Supply Voltage
Supply Current
SR & IR
LR
Symbol
V
CCA’
V
CCD
I
V
PP
V
OH
V
OL
Minimum
4.75
-
-
0.4
2.7
0
Typical
5.0
195
225
0.5
-
-
Maximum
5.25
250
275
1.0
V
CC
0.7
Units
V
mA
V
V
V
Output Voltage Swing (DATA)
Output HIGH Voltage (SIGNAL DETECT)
Output LOW Voltage (SIGNAL DETECT)
Related OC-48/STM-16 Transceiver & Receiver Modules
STX-48
SRC-48
DTR-2488-SM
DTR-2488-SM2
DTC-48
: Transmitter Module (24-pin DIP)
: Receiver Module with Clock Recovery (24-pin DIP)
: Transceiver without Clock Recovery (industry standard 1x9 package)
: Transceiver without Clock Recovery (industry standard 2x9 package)
: Transceiver with Clock Recovery (industry standard 2x9 package)
Oplink Communications, Inc.
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R5.2008.04.30
SRX48
Application Notes
The receiver converts the incident optical power to a
photocurrent via a high performance P-I-N photodiode (Short
and Intermediate Reach version) or an avalanche photodiode
(Long Reach version). For the Short and Intermediate Reach
version, the photocurrent can be monitored via the voltage
drop across an external resistor connected between PM+
and V
CC
. For the Long Reach version, the photocurrent can
be monitored via the differential voltage across the two PM+
and PM- output pins. It is important to note that the Common
Mode voltage of these two monitor outputs (i.e. DC voltages
at PM+ and PM-) is high (- 60 V typical). The APD Bias Voltage
is temperature compensated to ensure stable operation over
the entire operating temperature range.
The DATA outputs are differential signals designed to
be AC-coupled into 50 ohm load. Transmission lines are
recommended for best performance.
The Signal Detect circuit monitors the level of the incoming
optical signal and generates a TTL logic LOW signal at the
SIGNAL DETECT output when insufficient photocurrent is
produced. No termination resistor is required for the SIGNAL
DETECT output.
V
CC
External
Monitor Resistor
(3 Kohm recommended)
PM+
APD
10 K
1K
PM+
10 K
PD
PM-
PD Current
Monitor
SRX-48
APD Bias
Supply
SRX-48
SHORT & INTERMEDIATE REACH
LONG REACH
Interface Circuit
1 µH coil or ferrite bead
(<0.2 ohm series resistance)
+5V
+
10
+
100
0.01
10
17,18
The AC coupling capacitor is typically
0.022
µ
F for 2.48 Gb/s. If operation at
lower data rates is required, a parrallel
combination of 0.022
µ
F &
0.22
µ
F (or larger) is recommended
+
10
50 ohm line
9
0.01
PM-
for LR only
for SR & IR only
SRX-48
22
8
DATA+
to 50 ohm load
50 ohm line
DATA-
to 50 ohm load
SIGNAL DETECT
+5V
+
10
0.01
20
3
4,5,6,7,11,12,13
14,15,16,19,21
Oplink Communications, Inc.
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R5.2008.04.30
SRX48
Package Outline
(Dimension in inches)
The pigtail length from the package
edge is 1.0 meter typical.
46335 Landing Pkwy Fremont, CA 94538 Tel: (510) 933-7200 Fax: (510) 933-7300 Email: Sales@Oplink.com • www.oplink.com
Pinout Assignments
PIN
1
2
3
4
5
6
7
8
9
10
11
12
FUNCTION
N/C (NO CONNECTION)
N/C (NO CONNECTION)
SD (SIGNAL DETECT)
GND
GND
GND
GND
DATA OUTPUT -
DATA OUTPUT +
V
CCD
(V
CC
DC-DC converter)
GND
GND (DC-DC converter)
PIN
24
23
22
21
20
19
18
17
16
15
14
13
FUNCTION
N/C (NO CONNECTION)
N/C (NO CONNECTION)
PM- (for LR), N/C (for SR & IR)
GND
PM+
GND
V
CCA
(V
CC
ANALOG)
V
CCA
(V
CC
ANALOG)
GND
GND
GND
GND
Ordering Information
SRX
8
4
8
X
0
0
0
Supply Voltage
5V= 8
Receivers
Wavelength
1100~1600nm PIN= R1
1100~1600nm APD= R2
Temperature Range
-40 ~85˚C= I
0~70˚C= H
Option
Pigtail FC= P1
Pigtail ST= P2
Pigtail SC= P3
Pigtail MU= P6
Pigtail LC= P9
Oplink Communications, Inc. reserves the right to make changes in equipment design or specifications without notice. Information supplied by Oplink Commu-
nications, Inc. is believed to be accurate and reliable. However, no responsibility is assumed by Oplink Communications, Inc. for its use nor for any infringements
of third parties, which may result from its use. No license is granted by implication or otherwise under any patent right of Oplink Communications, Inc.
R5. 2008.04.30
© 2008, Oplink Communications, Inc.
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