Data Sheet
March 2006
Wavelength-Selectable High-Power
D2547P-Type CW DFB Laser Module
Applications
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Telecommunications:
— Dense WDM
— SONET/SDH OC-192/ STM-64
— Extended and ultra-long reach
— Undersea systems
Digital video
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Description
The D2547P-Type DFB laser module is designed for
use with an external lithium niobate modulator and
also in applications where high power (20 mW) is
required.
The laser comes packaged in an industry-standard
14-pin butterfly module with a polarization-maintain-
ing fiber pigtail.
Temperature-stabilized with a thermoelectric cooler
(TEC) and thermistor, the package is available in C
and L band ITU-T grid wavelengths on a 100 GHz
spacing plan.
D2547P does not contain a wavelength locker, which
is not needed for high-reliability operation in
100GHz-spaced applications. For a 20 mW CW laser
butterfly version with integrated wavelength locker
and available on a 50 GHz grid, refer to the compan-
ion product data sheet for D3587P.
Featuring wavelength selection to the DWDM ITU-T grid, the
D2547P Laser Modules are ideally suited for use with external
lithium niobate modulators, and in high-power (20 mW) appli-
cations.
Features
n
High-performance, multiquantum-well (MQW),
distributed-feedback (DFB) laser
D2547P-Type is offered on 100 GHz ITU grid
wavelengths ranging from 1528.77 nm—
1610.06 nm
Polarization-maintaining fiber pigtail
For use with lithium niobate modulators
High optical power (20 mW, CW)
Hermetic, 14-pin package
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Wavelength-Selected, High-Power
D2547P-Type Isolated DFB Laser Modules
Data Sheet
March 2006
Description
(continued)
Controlled Feedback
The module contains an internal optical isolator that sup-
presses optical feedback in laser-based, fiber-optic sys-
tems. Light reflected back to the laser is attenuated a
minimum of 30 dB.
Pin Information
Table 1. Pin Descriptions
Pin
1
2
3
4
5
6
7
8
9
10
11
12
13
14
Thermistor
Thermistor
Laser dc Bias (Cathode) (–)
Back-facet Monitor Anode (–)
Back-facet Monitor Cathode (+)
TEC (+)
1
TEC (–)
1
Case Ground
D2547P-Type
Controlled Temperature
An integral TEC provides stable thermal characteristics.
The TEC allows for heating and cooling of the laser chip to
maintain a temperature constant as the case temperature
changes from –5 °C to +75 °C. The laser temperature is
monitored by the internal thermistor, which can be used
with external circuitry to control the laser chip temperature.
Controlled Power
An InGaAs PIN photodiode functions as the back-facet
power monitor. The photodiode monitors emission from the
rear facet of the laser and, when used in conjunction with
control circuitry, can control optical power launched into the
fiber. Normally, this configuration is used in a feedback
arrangement to maintain consistent laser output power.
Case Ground
Case Ground
Laser Anode (+)
Laser Input Cathode (–)
Laser Anode (+)
Case Ground
1. A positive current through the thermoelectric heat pump cools the
laser.
Standard Package
The laser module is fabricated in a 14-pin, hermetic, metal/
ceramic butterfly package.
The laser module is equipped with
Fujikura
®
polarization-
maintaining fiber (PMF). The fiber is PANDA type it has a
mode field diameter of 10.5
µm,
a cladding diameter of
125
µm
± 3
µm,
and a tight-buffered coating, all within a
900
µm
diameter, loose tube jacket. Figure 1 shows the ori-
entation of polarization in the fiber without the loose tubing.
CyOptics’ optoelectronic components are qualified to rigor-
ous internal standards that are consistent with
Telcordia
Technologies
™
TR-NWT-000468. All design and manufac-
turing operations are
ISO
®
9001 certified.
CORE
STRESS ROD
PRINCIPLE POLARIZATION
AXIS
CLADDING
INNER COATING
(SILICON & ACRYLATE)
OUTER COATING
1-771(C).a
Figure 1. Polarization-Maintaining Fiber without Jacket
2
For additional information and latest specifications, see our website:
www.cyoptics.com
Data Sheet
March 2006
Wavelength-Selected, High-Power
D2547P-Type Isolated DFB Laser Modules
Functional Description
7
–
6
+
5
+
4
–
L1
140 nH
3
–
TH
10 kΩ
2
1
TEC
PACKAGE
GROUNDS
+
8
9
10
11
R1
20
Ω
–
12
ISOLATOR
NC
+
13
14
1-567
Top view.
Figure 2. D2547P Circuit Schematic
1-1129(F)
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www.cyoptics.com
3
Wavelength-Selected, High-Power
D2547P-Type Isolated DFB Laser Modules
Data Sheet
March 2006
Absolute Maximum Ratings
Stresses in excess of the absolute maximum ratings can cause permanent damage to the device. These are abso-
lute stress ratings only. Functional operation of the device is not implied at these or any other conditions in excess
of those given in the operations sections of the data sheet. Exposure to absolute maximum ratings for extended
periods can adversely affect device reliability.
Parameter
Laser DC Reverse Voltage
Laser DC Forward Current
Operating Case Temperature Range
Storage Case Temperature Range
1
Photodiode dc Reverse Voltage
Photodiode dc Forward Current
Thermistor Temperature
3
Thermoelectric Cooler in Heating Mode
3
1. Does not apply to shipping container.
2. Maximum 2000 hrs. at extreme conditions.
3. To prevent package over-temperature conditions.
Symbol
V
RLMAX
I
FLMAX
T
C
T
stg
V
RPDMAX
I
FPDMAX
—
I
TEC
Min
—
—
–5
–40
—
—
—
—
Max
2
225
75
85
2
10
2
100
0.5
Unit
V
mA
°C
°C
V
mA
°C
A
Handling Precautions
Power Sequencing
To avoid the possibility of damage to the laser module
from power supply switching transients, follow this
turn-on sequence:
1. All ground connections
2. Most negative supply
3. Most positive supply
4. All remaining connections
Reverse the order for the proper turn-off sequence.
Mounting Instructions
The minimum fiber bend radius is 1.0 in. (25.4 mm).
To avoid degradation in performance, mount the mod-
ule on the board as follows:
1. Place the bottom flange of the module on a flat heat
sink at least 0.5 in. x 1.180 in. (12.7 mm x 30 mm) in
size. The surface finish of the heat sink should be
better than 32
µin.
(0.8
µm),
and the surface flatness
must be better than 0.001 in. (25.4
µm).
Using ther-
mal conductive grease is optional; however, thermal
performance can be improved by up to 5% if conduc-
tive grease is applied between the bottom flange and
the heat sink.
2. Mount four #2-56 screws with Fillister heads
(M2-3 mm) at the four screw hole locations (see Out-
line Diagram). The Fillister head diameter must not
exceed 0.140 in. (3.55 mm). Do not apply more than
1 in.-lb. of torque to the screws.
0.062 (1.58)
0.031 (0.79)
0.140
(3.56)
0.129 (3.28) R
0.041 (1.04)
Note: Dimensions are in inches and (millimeters).
1-532(C)
Electrostatic Discharge
CAUTION: This device is susceptible to damage as
a result of electrostatic discharge. Take
proper precautions during both han-
dling and testing. Follow guidelines
such as JEDEC Publication No. 108-A
(Dec. 1988).
CyOptics employs a human-body model (HBM) for
ESD-susceptibility testing and protection-design evalu-
ation. ESD voltage thresholds are dependent on the
critical parameters used to define the model. A stan-
dard HBM (resistance = 1.5 kΩ, capacitance = 100 pF)
is widely used and, therefore, can be used for compari-
son purposes.
0.118
(3.00)
0.086
(2.18)
Figure 3. Fillister Head Screw
4
For additional information and latest specifications, see our website:
www.cyoptics.com
Data Sheet
March 2006
Wavelength-Selected, High-Power
D2547P-Type Isolated DFB Laser Modules
Characteristics
Minimum and maximum values are testing requirements. Typical values are device characteristics and are results
of engineering evaluations; they are for information purposes only and are not part of the testing requirements. All
parameters are beginning of life, unless otherwise specified.
Table 2. D2547P-Type Electrical Characteristics
Parameter
Threshold Current
Drive Current
Laser Forward Voltage
Monitor Reverse-bias Voltage
1
Back-facet Monitor Current:
Monitor Dark Current
Input Impedance
Thermistor Current
Resistance Ratio
2
Thermistor Resistance
Laser Submount Temperature
TEC Current
TEC Voltage
TEC Capacity
Symbol
I
TH
—
V
LF
V
RMON
I
RMON
I
D
Z
IN
I
TC
—
R
TH
T
LASER
I
TEC
V
TEC
∆T
Test Conditions
—
L
F
= 20 mW
L
F
= 20 mW (CW)
—
P
O
= 20 mW (CW)
I
F
= 0, V
RMON
= 5 V
—
—
—
T
L
= 25 °C
—
T
C
= 75 °C
T
C
= 75°C
T
C
= 75 °C
Min
—
—
—
3
0.2
—
—
10
9.1
9.5
20
—
—
—
Typ
15
—
2
5
—
0.01
25
—
9.6
—
—
—
—
—
Max
40
165
2.5
10
3.0
0.1
—
100
10.1
10.5
35
1.2
2.5
55
Unit
mA
mA
V
V
mA
µA
Ω
µA
—
kΩ
°C
A
V
°C
1 Standard operating condition is 5.0 V reverse bias.
2 Ratio of thermistor resistance at 0 °C to thermistor resistance at 50 °C.
Table 3. D2547P-Type Optical Characteristics
Parameter
Optical Output Power
Center Wavelength*
(See Ordering Information)
Line Width (3 dB full width)
Side-mode Suppression Ratio
Relative Intensity Noise
Optical Isolation
Optical Polarization Extinction
Ratio
†
FM Efficiency
Wavelength Drift (EOL)
Symbol
P
P
λ
C
∆λ
SMSR
RIN
—
—
FM
∆λ
C
Test Conditions
—
T
L
= T
SET
λ
C
=
λ
ITU
± 0.1 nm
CW, P
F
= 20.0 mW
CW
CW, P
F
= 20 mW
200 MHz < f < 10 GHz
T
C
= 0 °C to 75 °C
0 °C to 75 °C
P
F
= 20 mW
Tested over
25-year lifetime
Min
20.0
1528.77
—
35
—
30
20
—
—
Typ
—
—
2
45
—
—
—
100
—
Max
—
1610.06
10
—
–135
—
—
—
±0.1
Unit
mW
nm
MHz
dB
dB/Hz
dB
dB
MHz/mA
nm
* Custom wavelengths available.
† The ST ferrule key is not aligned to slow axis of fiber. Connector is intended for testing purposes only.
For additional information and latest specifications, see our website:
www.cyoptics.com
5