520
Coaxial Pigtailed Laser Module
Technical Data
LST252X - 200 µW Coaxial Laser
LST282X - 1 mW Coaxial Laser
LST292X - 1.6 mW Coaxial Laser
LST3X21 - Dual-in-Line Package
Features
• Compact Coaxial Package
• Strained Multi Quantum
Well (SMQW) Laser Chip
• Low Thresholds Current and
Operating Currents
• Wide Operating Tempera-
ture -40°C to +85°C
• Optical Power May Be
Customized up to 2 mW
• Modulation Capability up to
622 Mb/s
• Convenient Variety of
Pinout and Mounting Flange
Options
Applications
• Telecommunications
• Fiber in the Loop
• Inter/Intra Office
• SONET/SDH
• Datacommunications
• Switches
Description
Products in the LST2X2X family
are compact coaxial pigtailed
laser transmitters, operating in
the 1300 nm wavelength region
and coupling light to single mode
fiber. They are designed for use
in short, medium and long
distance networks with bit rates
up to 622 Mb/s.
The device features a high
reliability SMQW laser diode and
rear facet monitor photodiode.
These are electrically connected
to four pins in an industry-
standard configuration.
Environmental performance is
designed to be compatible with
the requirements of Bellcore’s
TA-NWT-000983 document.
Options within the LST2X2X
family offer pinouts and pin
rotational orientations designed
to match existing products
available on the market. We also
offer a comprehensive range of
alternative mounting flanges
including a dual in line option.
If the specific arrangement or
performance you require is not
listed, please contact your local
representative as our highly
flexible design and manufacturing
processes allow both physical and
electro-optical customization to
meet your needs.
Laser Safety Warning
This device is a Class IIIb (3b) Laser Product. It may emit invisible laser radiation if operated with the fiber pigtail disconnected. To avoid
possible eye damage do not look into an unconnected fiber pigtail during laser operation. Do not exceed specified operating limits.
5965-7336E (4/97)
521
Limits
Parameter Symbol Test Condition Min. Max. Units
Laser Forward Current If DC 120 mA
Laser Reverse Voltage Vlr DC 2 V
Photodiode Reverse Voltage Vr DC 20 V
Photodiode Forward Current Ipf DC 1 mA
Operating Temperature Tc Temperature measured at case –40 +85 °C
Storage Temperature Ts –40 +85 °C
Relative Humidity RH noncondensing %RH
Fiber Pull Strength Three times; 10 sec. 10 N
Mechanical Shock MIL-STD-883D, Method 2002, 500 G
Condition A
Vibration MIL-STD-883D, Method 2007, 20 G
Condition A
Absolute Maximum Ratings
Absolute limiting (maximum) ratings mean that no catastrophic damage will occur if the product is subjected to these ratings for short periods,
provided that each limiting parameter is in isolation and all other parameters have values within the performance specification. It should not be
assumed that limiting values of more than one parameter can be applied to the product at the same time.
Performance Specifications
LST252X LST282X LST292X
LST3521 LST3821 LST3921
Parameter Symbol Test Condition Min. Max. Min. Max. Min. Max. Units
LASER CW, Tc = –40°C to
+85°C, Po as noted
below unless otherwise
stated
Rated Optical Power Po Tc = ranges specified 0.2 1.0 1.6 mW
above, CW
Threshold Current Ith Tc = +25°C 3.5 10 3.5 10 3.5 10 mA
Threshold Current Ith 1.5 30 1.5 30 1 30 mA
Coupled Power in Pth If = Ith – 2 mA 10 10 10 µW
“Off” State
Slope Efficiency ηTc = +25°C 1016508080128µW/mA
Drive Current above Id Tc = +25°C 12.5 20 12.5 20 12.5 20 mW
Ith, for Im = Im
(Po, +25°C) Tc = –40°C to +85°C 10 33.3 10 33.3 10 33.3 mA
Forward Voltage Vf 1.6 1.6 1.6 V
Center Wavelength λTc = +25°C 1286 1336 1286 1336 1286 1336 nm
Tc = –40°C to +85°C 1260 1360 1260 1360 1260 1360 nm
Wavelength/ ∆λ/∆T 0.4 0.4 0.4 nm/°C
Temperature
Coefficient
Spectral Width σOne sigma, RMS 2.5 2.5 2.5 nm
Rise and Fall Time τ10-90%, Ith to Po 0.5 0.5 0.5 ns
522
Performance Specifications (continued)
LST252X LST282X LST292X
LST3521 LST3821 LST3921
Parameter Symbol Test Condition Min. Max. Min. Max. Min. Max. Units
MONITOR Tc = +25°C, Vr = 5 V,
PHOTODIODE Po = Rated Power
Photocurrent Im 200 1000 200 1000 200 1000 µA
Dark Current Id Po = 0 µW202020nA
Capacitance C 1 MHz 10 10 10 pF
Tracking Error DR Im = Im (Po, +25°C) –1 +1 –1 +1 –1 +1 dB
Tc + –40°C to + 85°C
Rise and Fall Time tr 10-90%, Ith to Po 2 2 - ns
Fiber Pigtail
Parameter Minimum Maximum Units
Fiber Pigtail Length 1000 mm
Spot Size (Mode Radius) 4.5 5.5 µm
Cladding Diameter 122 128 µm
Core/Cladding Concentricity 1 µm
Secondary Jacket Diameter 0.8 1 mm
Effective Cutoff Wavelength 1150 1240 nm
Reliability Target
Parameter Condition Min. Max. Units
Median Life 50% inc. in total drive current, Tc = +25°C 2x105hours
Other Documentation
SMQW Laser Diode Reliability Datasheet Publication number 5965-1293E
LST282X/LST292X/LST3821/LST3921
Interim Qualification Report Publication number 5965-5374E
523
H
N
I
L
M
F
K
G
P – PIN DIAMETER
R
J
Q
BCO
A
D
MIN. TYP. MAX.
11.8
2.4
12.5
7.4
17.0
3.7 12.2
2.6
12.9
A
B
C
D
E
F
MIN. TYP. MAX.
12.0
2.1
5.3
2.0
1000
20.0
2.3
G
H
I
J
K
L
DIM. DIM. MIN. TYP. MAX.
0.4
0.9
5.3
2.0
0.5
1.25
0.5
M
N
O
P
Q
R
DIM.
E
LST3X21 Specification – All dimensions in mm.
Example of LST2X2X – All dimensions in mm.
FUNCTION
MONITOR ANODE (-VE)
MONITOR CATHODE (+VE)
LASER CATHODE (-VE)
LASER ANODE (+VE)
1
2
3
4
PIN
41
32
CASE
LASER
LST2X25
PHOTODIODE
2
PHOTODIODE
LASER
1
4
3
CASE FUNCTION
LASER CATHODE (-VE)
MONITOR CATHODE (+VE)
MONITOR ANODE (-VE)
LASER ANODE (+VE)
1
2
3
4
PIN
LST2X27
LST2X25 LST2X27
PINOUT OPTIONS
524
ABC
D
H
TYP.
12.60
7.62
2.54
30.00
A
B
C
D
DIM.
4
3
2
1
5
6
7
8
C/L
E
PIN 1 INDICATOR
F
I
G
4
3
2
1
5
6
7
8
PHOTODIODE
LASER
CASE FUNCTION
NO CONNECTION
MONITOR ANODE (-VE)
MONITOR CATHODE (+VE)
NO CONNECTION
NO CONNECTION
LASER CATHODE (-VE)
LASER ANODE (+VE)
1
2
3
4
5
6
7
PIN
(CONNECTED TO HEADER)
NO CONNECTION
8
TYP.
10.20
12.60
4.26
3.53
E
F
G
H
DIM.
NOTE:
PINS 1, 4, 5, AND 8 ARE ISOLATED
FROM THE INTERNAL CIRCUITRY,
BUT ARE ELECTRICALLY CONNECTED
TO EACH OTHER.
PINS 1, 4, 5, & 8 – 0.51 x 0.38 NOM.
PINS 2, 3, 6, & 7 – 0.4/0.5 DIA.
K
J
TYP.
2.54
8.60
3.20
1000
I
J
K
M
DIM.
OPTION 1
M
LST3X21 Specification – All dimensions in mm.
525
Ordering Information
Coaxial Package
LST2X2X - XX - Y - ZZ
Connector Type:
FP = FC/PC
ST* = ST
SC = SC
DN = DIN
SF = Superpolish FC/PC
Flange:
B = Without mounting flange
T = Universal flange
Empty = 155 Mb/s operation
S4 = 622 Mb/s operation
Pinout:
5 = see pinout diagram
7 = see pinout diagram
Power:
5 = Po = 200 µW
8 = Po = 1 mW
9 = Po = 1.6 mW
Dual-in-Line Package
LST3X21 - XX - ZZ
Connector Type:
FP = FC/PC
ST* = ST
SC = SC
DN = DIN
SF = Superpolish FC/PC
Empty = 155 Mb/s operation
S4 = 622 Mb/s operation
Power:
5 = Po = 200 µW
8 = Po = 1 mW
9 = Po = 1.6 mW
*ST® is a registered trademark of AT&T.
