D2587_47 TriQuint Semiconductor, D2587_47 Datasheet - Page 2

• Manufacturer Part Number: D2587_47
• Description: Type ISOlated DFB Laser Modules
• Manufacturer: TriQuint Semiconductor

Locker)/D2547P-Type Isolated DFB Laser Modules
Description
Controlled Wavelength (D2587-Type)
The single-channel, wavelength-selected DFB (ILM) pack-
age contains internal wavelength-discriminating optics, i.e.,
two etalons and two associated photodiodes. The output
consists of analog signals suitable for controlling the electri-
cal current of the thermoelectric cooler (TEC) and the DFB
laser. To maintain constant laser frequency, the ratio of the
etalon detector signal to that of the power detector, R_R
(the response ratio), must be kept constant.
Agere provides the beginning-of-life values for six parame-
ters: laser drive current; the single target ITU channel fre-
quency; laser thermistor resistance for the single specified
operating point; the etalon (1 or 2), which is qualified for use
with the module, R_R
at ITU point.
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.
Controlled Temperature
An integral TEC provides stable thermal characteristics.
The TEC allows for heating and cooling of the laser chip to
maintain a temperature of 25 °C for case temperatures from
–5 °C to +70 °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
A third internal, InGaAs, unfiltered 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 out-
put power.
Standard Package
The laser module is fabricated in a 14-pin, hermetic, metal/
ceramic butterfly package that incorporates a bias tee that
separates the dc-bias path from the RF input. The RF input
has a nominal 25 Ω impedance.
The laser module is equipped with Fujikura
maintaining fiber (PMF). The fiber is PANDA type and is the
2 2
(continued)
REF
; and the sign of local etalon slope
®
polarization-
REF
same fiber that is used on the Agere Systems Inc. lithium
niobate modulators. It has a mode field diameter of
10.5 µm, a cladding diameter of 125 µm ± 3 µm, and a tight-
buffered outer jacket diameter of 900 µm. Figure 1 shows
the orientation of polarization in the fiber.
Agere Systems’ optoelectronic components are being quali-
fied to rigorous internal standards that are consistent with
Telcordia Technologies
manufacturing operations are ISO
module is being fully qualified for central office applications.
Pin Information
Table 1. Pin Descriptions
1. A positive current through the thermoelectric heat pump cools the
2. Both leads should be grounded for optimum performance.
Pin
laser.
10
11
12
13
14
1
2
3
4
5
6
7
8
9
For additional information and latest specifications, see our website: www.triquint.com
Figure 1. Polarization-Maintaining Fiber
Thermistor
Thermistor
Laser dc Bias
(Cathode) (–)
Back-facet Monitor
Anode (–)
Back-facet Monitor
Cathode (+)
TEC (+)
TEC (–)
Case Ground
λ Photodiode 2 Anode
λ Photodiode 1 Anode
Laser Anode (+)
RF Laser Input
Cathode (–)
Laser Anode (+)
NC
D2587P-Type
1
1
™
2
2
TR-NWT-000468. All design and
Thermistor
Thermistor
Laser dc Bias
(Cathode) (–)
Back-facet Monitor
Anode (–)
Back-facet Monitor
Cathode (+)
TEC (+)
TEC (–)
Case Ground
Case Ground
Case Ground
Laser Anode (+)
RF Laser Input
Cathode (–)
Laser Anode (+)
Case Ground
®
CORE
STRESS ROD
PRINCIPLE POLARIZATION
AXIS
CLADDING
INNER COATING
(SILICON & ACRYLATE)
OUTER COATING
9001 certified. The
D2547P-Type
January 2003
1
1
2
2
1-771(C).a