Data Sheet, Rev. 1
September 2002
C482, C484, and C486 (C48-Type)
2.5 Gbits/s Cooled Laser Transmitters
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Automatic optical power control
Wide operating case temperature range,
–15 °C to +70 °C
Laser bias monitor alarm/laser degrade alarm
Laser back-facet monitor output
Transmitter-enable input
FC/PC or SC/PC connectors
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Applications
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Telecommunications:
— SONET/SDH SR/IR/LR
— Subscriber loop
— Metropolitan area networks
High-speed data communications
Offering multiple output power options and SONET/SDH com-
patibility, the C48-Type 2.5 Gbits/s Cooled Laser Transmitters
are manufactured in a 24-pin plastic DIP with a single-mode
fiber pigtail.
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Description
The C48-type 2.5 Gbits/s cooled laser transmitters
are designed for use in transmission systems and
high-speed data communication applications. The
transmitter operates at the SONET OC-48 rate, as
well as the ITU-T SDH rate of STM-16. The device
supports two wavelengths. The second wavelength
is selectable via pin 10.
The transmitters meet all present
Telcordia Technol-
ogies
TM
GR-253-CORE requirements and the ITU-T
G.957 and G.958 recommendations. They are also
ideally suited for extended-distance data and net-
working applications.
Manufactured in a 24-pin DIP, the transmitter incor-
porates a hermetic multiquantum well (MQW) iso-
lated 1550 nm digital distributed feedback (DFB)
laser (D2526 versions), an InGaAs PIN photodiode
back-facet monitor, and a GaAs laser driver IC. The
unit uses two power supplies. The laser transmitter
requires 5 V, and the thermoelectric cooler (TEC)
requires 3.3 V. The clock may be enabled for those
applications where jitter is critical.
Pin information is listed in Table 1.
Features
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Data rates to 2.5 Gbits/s
Two-channel selectable at 100 GHz spacing
SONET and ITU-T compliant at OC-48 and
STM-16
Cooled, InGaAsP MQW-DFB laser
Wavelength range, 1528.77 nm—1563.86 nm
User-selectable wavelengths
Clocked or nonclocked operation with single-ended
inputs; clocked operation with differential input
50
Ω
ac-coupled PECL compatible data and clock
inputs
Operation from 3.3 V and 5 V power supplies
Low-profile, 24-pin package
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C482, C484, and C486 (C48-Type)
2.5 Gbits/s Cooled Laser Transmitters
Data Sheet, Rev. 1
September 2002
Table 1. Pin Descriptions
Pin Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Name
Ground (TEC)
Back-facet Monitor
1
Bias Monitor/Laser Degrade Alarm
1
Tx Enable
Clock Select
Ground
Wavelength-Deviation Error Alarm
NUC
2
NUC
2
Wavelength Selection Command
3
Ground
V
EE4
V
CC
VTEC (TEC supply voltage)
Ground
DATA
Ground
DATA
Ground
CLOCK
Ground
CLOCK
Ground
V
CC
Transmitter Processing
The transmitter can withstand normal wave soldering
processes. The complete transmitter module is not her-
metically sealed; therefore, it should not be immersed
in, or sprayed with, any cleaning solution or solvents.
The process cap and fiber pigtail jacket can deform at
temperatures greater than 85 °C. The transmitter pins
can be wave-soldered at a maximum temperature of
250 °C for 10 seconds.
Installation Considerations
Although the transmitter has been designed with rug-
gedness in mind, care should be used during handling.
The optical connector should be kept free from dust,
and the process cap should be kept in place as a dust
cover when the device is not connected to a cable. If
contamination is present on the optical connector, the
use of canned air with an extension tube should
remove any debris. Other cleaning procedures are
identified in the
Cleaning Fiber-Optic Assemblies
Tech-
nical Note (TN95-010LWP).
Connector Options
The standard fiber-optic pigtail is an 8
µm
core single-
mode fiber in a 0.036 in. (914
µm)
diameter, tight-buff-
ered outer jacket. The standard length is 39 in. ± 4 in.
(1 m ± 10 cm) and is terminated with an FC/PC or
SC/PC optical connector. Other connector options may
be available on special order. Please contact your
Account Manager at Agere Systems Inc. for ordering
information.
1. Laser back-facet (pin 2) and bias alarm functions (pin 3) are cus-
tomer-use options that are not required for normal operations of
the transmitter and are normally used during manufacture and for
diagnostics. Pin 3 output will optionally be either an analog bias
monitor (default) or a digital logic signal (LDA). (See Table 2.)
2. Pins designated no user connection (NUC) must
not
be tied to
ground or any other circuit potential.
3. When logic 0, the nominal channel wavelength (n) is selected;
when logic 1, the n – 1 channel wavelength is selected.
4. V
EE
is not used. This pin is NUC. The V
EE
labeling is maintained
for MSA purposes.
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
Symbol
—
T
C
T
stg
—
RH
—
V
TEC
Min
—
–15
–40
—
—
1.00 (25.4)
—
Max
5.25
70
85
250/10
85
—
3.5
Unit
V
°C
°C
°C/s
%
in. (mm)
V
Supply Voltage
Operating Case Temperature Range
Storage Case Temperature Range
Lead Soldering Temperature/Time
Relative Humidity (noncondensing)
Minimum Fiber-bend Radius
TEC Voltage
2
Agere Systems Inc.
Data Sheet, Rev. 1
September 2002
C482, C484, and C486 (C48-Type)
2.5 Gbits/s Cooled Laser Transmitters
Characteristics
Minimum and maximum values specified over operating case temperature range at 50% duty cycle data signal.
Typical values are measured at room temperature unless otherwise noted.
Table 2. Electrical Characteristics
Parameter
dc Power Supply Voltage
dc Power Supply Current:
C482, C484
C486
Power Dissipation
Input Data/Clock Voltage:
1, 2
Single-ended Input
Differential Input
Nonclocked/Clocked Select Voltage:
3, 4
Clocked Operation
Nonclocked Operation
Input Impedance
Transmitter Enable Voltage (TTL) V
IL
Transmitter Disable Voltage (TTL) V
IH
Wavelength Selection Voltage (TTL) V
IL
Wavelength Selection Voltage (TTL) V
IH
λ
Deviation Alarm:
Levels (CMOS) V
OL
Levels (CMOS) V
OH
Setting (active-high)
5
Laser Bias Monitor Voltage (default)
Laser Degrade Alarm (option):
Levels (CMOS) V
OH
Levels (CMOS) V
OL
Setting (active-low)
Laser Back-facet Monitor Voltage (50% duty
cycle)
6
Clock Duty Cycle
TEC Current
TEC Voltage
Return Loss:
7, 8
Input Data
Input Clock
Symbol
V
CC
I
CC
I
CC
P
DIS
V
IN
V
IN
V
SEL_CLK
V
DIS_CLK
R
IN
V
EN
V
DIS
V
λN
V
λN
– 1
V
NO-λALARM
V
λALARM
λ
ALARM
V
LBM
V
NO-ALARM
V
ALARM
LD
ALARM
V
BF
C
DC
I
TEC
V
TEC
RL
DATA
RL
CLK
Min
4.75
—
—
—
250
125
0.0
2.0
—
0.0
2.0
0.0
2.0
0
4.5
–100
—
4.5
0
—
—
40
—
3.0
–10
–12
Typ
5.0
350
—
4.5
900
450
—
—
50
—
—
—
—
—
—
—
20
—
—
—
500
50
0.6
3.3
—
—
Max
5.25
400
500
5.2
1300
650
0.8
V
CC
—
0.8
V
CC
0.8
V
CC
0.3
V
CC
100
—
V
CC
0.3
55
—
60
1.2
3.5
—
—
Unit
V
mA
mA
W
mVp-p
mVp-p
V
V
Ω
V
V
V
V
V
V
pm
mV/mA
V
V
mA
mV/mW
%
A
V
dB
dB
1. Inputs are ac-coupled into an equivalent input impedance of 50
Ω.
2. Single-ended or differential operation may used. If the inputs are driven single-ended, the unused inputs must be terminated in 50
Ω.
3. Clocked operation is optional. For clocked operation, pin 5 must be a logic 0. With clocked operation, the optical output changes state with
the rising edge of the input clock signal.
4. If left unselected, clocked operation will be selected.
5. Deviation due to temperature variation detected by the thermistor.
6. This voltage is measured from pin 2 to GND.
7. Frequency range: 100 kHz—2 GHz.
8. At frequency of 2.5 GHz.
Agere Systems Inc.
3
C482, C484, and C486 (C48-Type)
2.5 Gbits/s Cooled Laser Transmitters
Data Sheet, Rev. 1
September 2002
Characteristics
(continued)
Table 3. Optical Characteristics
Parameter
Average Optical Power Output:
1
C482, C484
Average Optical Power Output:
1
C486
Output Power Variation (over temperature and
wavelength)
Center Wavelength Range (See Tables 6—11.)
Wavelength Accuracy
2
Wavelength Variation and Aging
2
Wavelength Chirp (on-state/off-state
λ)
3
Side-mode Suppression Ratio
4
Jitter, Intrinsic
5
Extinction Ratio
6
Eye Mask of Optical Output
7, 8
Optical Rise/Fall Time (20%—80%):
C482, C484
C486
Maximum Return Loss (optical)
Symbol
P
AVG BOL
P
AVG EOL
P
AVG BOL
P
AVG EOL
∆P
λ
C
∆λ
C
∆λ
C
∆λ
SMSR
—
r
e
—
t
R,
t
F
t
R,
t
F
O
RL
Min
0
–0.5
6.0
5.5
–0.5
1528.77
–0.015
–0.100
—
30
—
8.2
Typ
1.0
—
6.7
—
—
—
—
—
—
—
—
—
Max
2.0
2.0
8.0
8.5
0.5
1563.86
0.015
–0.100
0.20
—
0.05
—
Unit
dBm
dBm
dBm
dBm
dBm
nm
nm
nm
nm
dB
UIp-p
dB
—
ps
ps
dB
Meets SONET and ITU-T
—
—
—
—
—
—
130
150
24
1. Output power definitions and measurement per ITU-T Recommendation G.957.
2. At room temperature; takes into account the initial variation in temperature as well as long-term aging. Please refer to the applica-
tion note,
Wavelength Tolerance in DWDM
for more information on this value.
3. Measured using time resolved spectroscopy (TRS). This corresponds to approximately 0.3 nm maximum at full width 20 dB down
using a spectrometer with resolution of 0.05 nm.
4. Ratio of the average output power in the dominant longitudinal mode to the power in the most significant side mode under fully
modulated conditions.
5. Filter bandwidth from 12 kHz—20 MHz, according to ITU-T G813.
6. Ratio of logic 1 output power to logic 0 output under fully modulated conditions; with fourth-order Bessel-Thomson filter on.
7. GR-253-CORE,
Synchronous Optical Network (SONET) Transport Systems: Common Generic Criteria.
8. ITU-T Recommendation G.957,
Optical Interfaces for Equipment and Systems Relating to the Synchronous Digital Hierarchy.
4
Agere Systems Inc.
Data Sheet, Rev. 1
September 2002
C482, C484, and C486 (C48-Type)
2.5 Gbits/s Cooled Laser Transmitters
Characteristics
(continued)
Table 4. Dispersion Performance
Parameter
Dispersion Penalty for Extended Reach:
C482, C486
C484
Table 5. Data Timing
Symbol
t1
t2
Setup (Min)
35
—
Hold (Min)
—
60
Unit
ps
ps
Symbol
DP
DP
Test Conditions
1800 ps/nm
3000 ps/nm
Min
—
—
Typ
—
—
Max
2.0
2.0
Unit
dB
dB
CLOCK
t1
t2
DATA/DATA
Figure 1. Data Timing Diagram
1-1051(F)
Agere Systems Inc.
5