Data Sheet, Rev. 3
July 2001
D2570, D2526G, D2555 Wavelength-Selected
Direct Modulated Isolated DFB Laser Module
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 performance characteristics of the data sheet. Exposure to absolute maximum ratings for
extended periods can adversely affect device reliability.
Parameter
Laser Reverse Voltage
dc Forward Current
Operating Case Temperature Range
Storage Case Temperature Range*
Photodiode Reverse Voltage
Photodiode Forward Current
* Does not apply to shipping container.
Symbol
V
RLMAX
I
FLMAX
T
C
T
stg
V
RPDMAX
I
FPDMAX
Min
—
—
–40
–40
—
—
Max
2
150
70
85
10
2
Unit
V
mA
°C
°C
V
mA
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 1.23 in (31.25 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 con-
ductive 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
Outline 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)
1-532
Electrostatic Discharge
CAUTION:
This device is susceptible to damage
as a result of electrostatic discharge.
Take proper precautions during both
handling and testing. Follow guide-
lines such as JEDEC Publication No.
108-A (Dec. 1988).
0.118
(3.00)
0.086
(2.18)
Agere Systems employs a human-body model (HBM)
for ESD-susceptibility testing and protection-design
evaluation. ESD voltage thresholds are dependent on
the critical parameters used to define the model. A
standard HBM (resistance = 1.5 k¾, capacitance =
100 pF) is widely used and, therefore, can be used for
comparison purposes. The HBM ESD threshold pre-
sented here was obtained using these circuit parame-
ters:
Parameter
Human-body Model
Agere Systems Inc.
Value
>400
Unit
V
Note: Dimensions are in inches and (millimeters).
Figure 2. Fillister Head Screw
3
AGERE [ AGERE SYSTEMS ]
