Datasheet LSC2500-FP Datasheet (HP)

2.488 Gb/s DFB Laser Module
with Integral Optical Isolator

Technical Data

LSC2500

Features

• Center Wavelength Between
1535 nm and 1565 nm

• Modulation Capability up to

2.488 Gb/s

• 30 dB Internal Optical
Isolation

• 25 Ω Impedance Matched

• Wide Operating
Temperature Range: -20°C to
+65°C

• Industry Standard Hermetic
14 PIN Butterfly Package

Applications

• Telecommunications

• Fiber Optic Sensors

• Cable Television

• Military Communications
and Control Systems

• Instrumentation

Description

LSC2500 laser modules are
highly reliable fiber optic light
sources operating in the
1550 nanometer band. The
internal DFB lasers are based
upon InGaAs ridge waveguide
Multi Quantum Well technology
and fabricated by the Metal
Organic Vapor Phase Epitaxy
(MOVPE) process, resulting in
long lifetimes and modest
threshold currents.

The LSC2500 package includes a
photodiode for monitoring the
laser output, a thermistor for
monitoring laser heatsink
temperature, and a Peltier effect
thermoelectric cooler (TEC). A

heatsink mounting flange is
incorporated into the industry
standard 14 PIN package.

The LSC2500 also has 30 dB of
optical isolation which is
temperature controlled to
maintain isolation over the full
operating temperature range.

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.

5965-8213E (4/97)

559

LSC2500 Mechanical Outline

Top View

A

S

B

U

Side View

D

G

∅T

R

I

H

C

Back View

F

J

M

L

K

V

N

E

ALL DIMENSIONS IN MILLIMETERS

P

DIM.

A
B
C
D
E
F
G
H

J
K
L
M
N
P
R
S
T
U
V

I

MIN.

29.6

20.6

12.45

8.4
–
–

5.40
–
–
–
–
–

1500.00
–

4.5

8.8

25.9

2.50
–
–

NOM.

–
–
–
–

0.75

12.0
–

2.54

0.50

0.20

7.0

30.0
–

2.0
–
–
–
–

0.75

17.8

MAX.

30.4

21.1

12.95

9.0
–
–

5.90
–
–
–
–
–
–
–

6.5

9.0

26.1

2.70
–
–

LSC2500 Pin Connections and Block Diagram

Top View

7654321

TEC

8 9 10 11 12 13 14

560

PIN CONNECTIONS

THERMISTOR

1

THERMISTOR

2

LASER DC BIAS

3

MONITOR ANODE

4

MONITOR CATHODE

5

TEC

6

TEC

7

GROUND

8

GROUND

9

NOT CONNECTED

10

GROUND

11

LASER MODULATION

12

GROUND

13

NOT CONNECTED

14

LSC2500 Typical Operating Characteristics

0

-10

-30
1000 4000 6000 7000

0

-20

REL. POWER (dB)

FREQUENCY (MHz)

3000

2000 5000

PRODUCT TYPE : LSC2500
MODULATION BIT RATE : 2.488 Gb/s
MODULATION DEPTH : 12% EXTINCTION RATIO

THRESHOLD CURRENT (Ith) mA 16.00
FORWARD VOLTAGE AT 3000 µW V 2.26
POWER AT Ith + 40 mA µW 1956.00
MONITOR CURRENT AT 2000 µW µA 629.39
PEAK WAVELENGTH (12% XR) nm 1545.04
SIDEMODE SUPPRESSION dB 45.99
SENSITIVITY (B-B) IE-10 dB -29.69
SENSITIVITY (B-B) IE-4 dB -33.27
SENSITIVITY (106 Km) IE-10 dB -28.28
SENSITIVITY (106 Km) IE-4 dB -32.34
Ssat 75.40
Svar 5.83

100

90
80
70
60
50
40
30

REL. POWER (dB)

20
10

0

1534

1536 1540 1542 1544

1538

WAVELENGTH (nm)

1546 1548 1550 1552 1556

1554

5.0

4.5

4.0

3.5

3.0

2.5

2.0

1.5

LASER VOLTS (V)

1.0

0.5
0

0

3020 50

10 40 60 100

DRIVE CURRENT (mA)

70 80 90

4000
3500
3000
2500
2000
1500
1000

FIBER POWER (µW)

500

0

400 800

0

200 600 1000 1600

MONITOR CURRENT (µA)

12001400

4000
3500
3000
2500
2000
1500
1000

FIBER POWER (µW)

500

0

0

3020 50

10 40 60 100

DRIVE CURRENT (mA)

70 80 90

561

Absolute Maximum Ratings at +25°C

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.

Parameter Minimum Maximum Units

Laser Forward Current - 150 mA
Laser Reverse Voltage - 3.0 V
Photodiode Forward Current - 1 mA
Photodiode Reverse Voltage (Vr) - –10 V
Fiber Pull Strength - 10 N
Operating Temperature (Case) –20 +65 °C
Storage Temperature –40 +85 °C
Mechanical Shock MIL-STD-883, Method 2002, Test Condition B
Vibration MIL-STD-883, Method 2007, Test Condition A
TEC Current - 1.1 A
TEC Voltage - 3.0 V

Performance Specifications – Laser

[1]

Parameter Minimum Typical Maximum Units

Threshold Current (Ith) 10 - 30 mA
Slope Efficiency

[3]

0.02 0.05 0.12 mW/mA
Rise Time: 10% to 90% - - 0.12 ns
Fall Time: 90% to 10% - - 0.12 ns
Peak Wavelength 1535 - 1565 nm
Spectral Width (–30 dB) Modulated - - 0.6 nm
Temperature Dependence of Peak Wavelength - 0.10 - nm/°C
Sidemodes (Modulated)
Dispersion Penalty (1800 ps/nm)
Tracking Error +65°C Case, +25°C Chip

[2]

[2]

[4]

- - –34 dB

- - 1.5 dB

- - 0.5 dB

–20°C Case, +25°C Chip - - 0.5 dB
Flatness of Frequency Response to 3 GHz - - ± 1.5 dB
Cut Off Frequency 3.5 4.3 - GHz

Notes:

1. At +25°C and Pf = 2 mW unless otherwise specified.

2. Measured at PRBS 2

3. Other slope efficiencies available on request.

4. Fiber output power change for constant monitor output current.

23-1

, 2.488 Gb/s, 12% extinction.

562

Performance Specifications – Monitor Photodiode

Parameter Minimum Maximum Units

Photocurrent (Im) at 2 mW 0.2 2.0 mA
Dark Current (Vr = –5 V) at +25°C - 100 nA

Thermistor

Test Conditions

TC = +25°C, Pf = 0 mW

Parameter Symbol unless otherwise stated Min. Max. Units

Resistance Rt 9.5 10.5 kΩ
Temperature Coefficient of Rt ∆Rt/∆T Typ. 4.4 %dR/K

β Constant

β

0°C to +50°C Typ. 3900 °K

Test Limits

TEC

Test Conditions

TC = +25°C, Pf = 0 mW

Parameter Symbol unless otherwise stated Min. Max. Units

TEC Cooling Current Ic ∆T = –40°C, Tc = +65°C - 1.0 A
TEC Heating Current Ih ∆T = –45°C, Tc = –20°C - 1.0 A
Voltage Vc ∆T = –20°C, to +65°C - 2.0 V

Test Limits

Fiber Pigtail: Tight jacketed, self-mode stripping, single mode fiber

Parameter Minimum Maximum Units

Length 1.0 - m
Spot Size (Mode Radius) 4.5 5.5 µm
Cladding Diameter 122 128 µm
Core/Cladding Concentricity - 1.0 µm
Secondary Jacket Diameter 0.8 1.0 mm
Effective Cutoff Wavelength 1150 1240 nm

Hewlett-Packard can offer a ruggedized fiber pigtail for this product range if extreme mechanical strength is
required. The pigtail length can be customized to your specific length, with a connector, to a tolerance of
± 25 mm.

563

Ordering Information

LSC2500 - XX

Connector Type:
FP = FC/PC Polish

Model Name:
LSC2500

Handling Precautions

1. The LSC2500 can be damaged
by current surges or
overvoltage.

2. Power supply transient
precautions should be taken.

3. Normal handling precautions
for electrostatic sensitive
devices should be taken.

CDRH Certification

Hewlett-Packard Ltd.
Whitehouse Road
Ipswich, Suffolk IP1 5PB
England

Manufactured:_______ Serial No:__________

Model No: _______
This product conforms to the applicable

requirements of 21 CFR 1040 at the date of
manufacture.

Laser Warning

564