2

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Lucent Technologies Inc.

Data Sheet

February 2000

Isolated DFB Laser Module

1.3

µm D2300-Type Digital

Description

The D2300-Type Digital Isolated DFB Laser Module

contains an internally cooled, InGaAsP, distributed-

feedback (DFB) laser designed for 1.3

µm applications.

The laser is designed to be used in OC-12/STM-4 (622

Mbits/s) and OC-48/STM-16 (2.488 Gbits/s) for long-

reach and extended-reach applications.

The device is available with an average output power of

0 dBm (3 dBm peak), which meets the SONET/SDH

standard.

Controlled Feedback

The module contains an internal optical isolator that

suppresses optical feedback in laser-based, fiber-optic

systems. Light reflected back to the laser is attenuated

a minimum of 30 dB.

Controlled Temperature

An integral thermoelectric cooler (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 –40 °C to +80 °C.

The laser temperature is monitored by the internal ther-

mistor, which can be used with external circuitry to con-

trol the laser chip temperature.

Controlled Power

An internal, InGaAs, PIN photodiode functions as the

back-facet monitor. The photodiode monitors emission

from the rear facet of the laser and, when used in con-

junction with control circuitry, can control optical power

launched into the fiber. Normally, this configuration is

used in a feedback arrangement to maintain the aver-

age laser output power.

Standard Package

The laser module is fabricated in a 14-pin, hermetic,

metal/ceramic butterfly package. The package also

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 a sin-

gle-mode fiber. The pigtail has an 8

µm core and

125

µm cladding with a 900 µm tight buffer coating.

Lucent Technologies Microelectronics Group optoelec-

tronic components are qualified to rigorous internal

standards that are consistent with

Telcordia Technolo-

gies TR-NWT-000468. All design and manufacturing

operations are

ISO * 9001 certified. The module is fully

qualified for central office applications.

*

ISO is a registered trademark of The International Organization for

Standardization.

Pin Information

* A positive current through the thermoelectric heat pump cools the

laser.

† Both leads should be grounded for optimum performance.

Top view.

Figure 1. Circuit Schematic

Pin

Name

1

Thermistor

2

Thermistor

3

Laser dc Bias (cathode) (–)

4

Back-facet Monitor Anode (–)

5

Back-facet Monitor Cathode (+)

6

Thermoelectric Cooler (+)*

7

Thermoelectric Cooler (–)*

8

Case Ground

9

Case Ground

10

Case Ground

11

12

RF Laser Input Cathode (–)

13

14

Case Ground

1-567

TEC

L1

160 nH

ISOLATOR

R1

20

Ω

PACKAGE

GROUNDS

–+

+

–

–

+–

+

76

5

4

3

2

1

8

9

10

11

12

13

TH

10 k

Ω

14