Data Sheet
April 2002
A1754W Wideband Wireless Laser Modules
Description
The A1754W laser module is a dense wavelength-
division multiplexing (DWDM) laser for analog wire-
less applications. It features a distributed-feedback
(DFB) chip that has been designed specifically for
radio frequency (RF) applications. The A1754W laser
module has a wide temperature range for reliable
performance in harsh node environments and narrow
transmitter designs. It also features low adiabatic
chirp to maximize signal quality in short and long
lengths of fiber. The laser’s excellent inherent linear-
ity minimizes degradation of the broadcast signals
caused by the quadrature amplitude modulation
(QAM) channels.
Features
I
I
I
I
I
I
I
The A1754W is available in a wide range of standard
ITU wavelengths.
Higher temperature rating
High output power, up to 20 mW
Excellent linearity
Standard ITU wavelengths
Advanced analog chip design
Reduces equipment requirements in the hub
Exceeds
Telcordia Technologies
™ 468 specifica-
tion
Applications
I
I
I
I
Wideband wireless systems
Narrow transmitter housing
Networks with limited fiber
Architectures using separate optical wavelengths
to carry targeted services
A1754W Wideband Wireless Laser Modules
Data Sheet
April 2002
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 operational sections of the data sheet. Exposure to absolute maximum ratings for extended
periods can adversely affect device reliability.
Parameter*
Operating Case Temperature Range
Storage Temperature Range
Monitor Photodiode Reverse Voltage
Laser Forward Current
Reverse Voltage (laser)
TEC Current
RF Input Power
Symbol
T
C
T
stg
V
MPD
I
F
V
R
I
TEC
P
RFIN
Min
–40
–40
—
—
—
—
—
Max
85
85
10
150
2
1.9
13
Unit
°C
°C
V
mA
V
A
dBm
* The device can withstand continuous exposure to the specified limits without damage.
Characteristics
Table 1. Key Characteristics
Parameter
Frequency Range
1
Frequency Response
1
Symbol
F
—
Conditions
—
I
F
= 60 mA,
T
OP
= 25 °C
Any 500 MHz
0.3 MHz to 2700 MHz
I
F
= 60 mA
I
F
= I
OP
I
F
= I
TH
+ 70 mA,
T = 25 °C
I
P
= I
OP
, T = T
OP
I
F
= 60 mA,
T = T
OP,
T
C
varied from min to > max
I
F
= 60 mA,
T
OP
= 25 °C,
measured at 500 MHz
I
F
= I
OP
Min
0.3
—
Typ
—
Max
2700
—
Unit
MHz
RF Return Loss
1
Optical Output Power
2
Laser Relative Intensity
Noise
Available Wavelengths
Wavelength Drift
3
RL
RF
P
O
RIN
λ
λ∆
—
8
—
1527.94
—
2
4
>16
—
<
–155
—
—
—
20
—
1563.1
0.04
dB p-p
dB p-p
dB
mW
dB/Hz
nm
nm
Adiabatic Chirp
FM
40
—
100
MHz/mA
Operating Case
Temperature Range
T
C
–40
—
85
°C
1. Tested on a resistively matched 50
Ω
to 25
Ω
impedance transformer.
2. P
O
Min at I
TH
+10 mA. P
O
varies depending upon I
OP
chosen, to Max of I
OP
= 100 mA.
3. Change in wavelength as case temperature is changed.
2
Agere Systems Inc.
Data Sheet
April 2002
A1754W Wideband Wireless Laser Modules
Characteristics
(continued)
Table 2. Additional Characteristics
Parameter
Bias Current
1
Threshold Current
Slope Efficiency
Monitor Photocurrent
Operating Chip Temperature
2
TEC Current
Symbol
I
B
I
TH
η
I
MON
T
OP
I
TEC
Conditions
BOL
25 °C, BOL
I
P
= I
TH
+ 20 and
I
TH
+ 60
I
OP
= 0 mA, V
RM
= 5 V,
T
OP
= 25 °C
I
F
= I
OP
–40
°C <
T
C
< +85 °C,
T
OP
= 15 °C—35 °C,
I
F
= 60 mA
T
OP
= 15 °C—35 °C over T
C
T
OP
= 25 °C
T
C
I
F
= I
OP
Min
—
—
0.08
10
18
–1.5
Max
120
30
—
200
35
1.5
Unit
mA
mA
mW/mA
µA/mW
°C
A
TEC Voltage
Thermistor Resistance
Optical Return Loss
Side Mode Suppression Ratio
V
TEC
R
TH
RL
SMSR
–2.5
—
40
30
3.8
10.5
—
—
V
kΩ
dB
dB
1. Bias point at which all specifications apply.
2. Chip temperature at which wavelength specification is met. Operating chip temperature is reported for each laser.
Electrical Schematics
1
ISOLATOR
2
NC
14
13
(+)
3
12
(–)
(–)
4
11
(+)
(+)
5
NC
CASE
GROUND
CASE
GROUND
10
(+)
6
9
(–)
7
TEC
8
1-1233(F)
Figure 1. A1754W Laser Schematic
3
Agere Systems Inc.
A1754W Wideband Wireless Laser Modules
Data Sheet
April 2002
Electrical Schematics
(continued)
14
NC
13
LASER
COMMON (+)
LASER
MODULATION (–)
LASER
COMMON (+)
THERMISTOR
1
THERMISTOR
dc LASER
BIAS
MPD ANODE
CASE GROUND
2
39 nH
3
200
Ω
4
1000 pF
SEE
FIGURE 4
3.3
µH
0.01
µF
SEE
FIGURE 3
12
11
10
NC
CASE
GROUND
CASE
GROUND
MPD CATHODE
5
1000 pF
9
TEC (+)
6
0.01
µF
8
TEC (–)
7
0.01
µF
1-1234(F)
Figure 2. A1754W Circuit Schematic
R1
37.5
Ω
SEE PIN 12,
FIGURE 2
R2
37.5
Ω
1-1238F.b
Figure 3. Resistive-Matched Configuration
4
Agere Systems Inc.
Data Sheet
April 2002
A1754W Wideband Wireless Laser Modules
Electrical Schematics
(continued)
TEC
CONSTANT
ALARM
THERMISTOR
1
THERMISTOR
dc LASER
BIAS
MPD ANODE
CASE GROUND
2
39 nH
3
200
Ω
4
1000 pF
5
1000 pF
3.3
µH
0.01
µF
J2
1 THERMISTOR
2 THERMISTOR
3 dc LASER BIAS
4 MPD ANODE (CASE GROUND)
5 MPC CATHODE
6 TEC (+)
7 TEC (–)
8 GND
9 GND
10 GND
MPC CATHODE
TEC (+)
6
0.01
µF
TEC (–)
7
0.01
µF
1-1238F.c
Note: When ordering the dc set, the following boards are included: alarm board, 9108-004; TEC board, 9028-004; constant current, 9383-004.
Figure 4. dc Set (Agere Systems-Supplied Option)
Agere Systems Inc.
5