AGERE D2587P910, D2587P9095, D2587P909, D2587P9085, D2587P908 Datasheet

Data Sheet, Rev. 2

July 2001

Wavelength-Selected High-Power D2587P-Type (with

Wavelength Locker)/D2547P-Type Isolated DFB Laser Modules

Featuring wavelength selection and locking capabilities, the D2587P Laser Module is ideally suited for use with external lithium niobate modulators, and in high-power (20 mW) applications.

Features

■High-performance, multiquantum-well (MQW), distributed-feedback (DFB) laser

■D2587P-Type is offered on 50 GHz ITU grid wavelengths ranging from 1528.77 nm— 1610.06 nm

■D2547P-Type is offered on 100 GHz ITU grid wavelengths ranging from 1528.77 nm— 1610.06 nm

■Polarization-maintaining fiber pigtail

■For use with lithium niobate modulators

■High optical power (20 mW, CW)

■Hermetic, 14-pin package

Applications

■Telecommunications:

—Dense WDM

—SONET/SDH OC-192/STM-64

—Extended and ultralong reach

—Undersea systems

■Digital video

Description

The D2587P-Type DFB laser module is designed for use with an external lithium niobate modulator and also in applications where high power (20 mW) is required.

The use of an internal wavelength locker greatly enhances long-term reliability and reduces chirp and mode dispersion when used in conjunction with LN modulators at OC-192 data rates.

A companion device, the D2547P high-power DFB laser module, is also designed for use with a lithium niobate external modulator, but without the use of an internal wavelength locker.

Wavelength-Selected, High-Power D2587P-Type (with Wavelength	Data Sheet, Rev. 2
Locker)/D2547P-Type Isolated DFB Laser Modules	July 2001

Description (continued)

Principles of Operation (Controlled Wavelength)

The single-channel, wavelength-selected DFB (ILM) package contains internal wavelength-discriminating optics, i.e., two etalons and associated photodiodes. The output consists of analog signals suitable for controlling the electrical current of the thermoelectric cooler (TEC) and the DFB laser.

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 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 –25 °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

An internal, InGaAs, PIN photodiode functions as the backfacet 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 output 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* polarizationmaintaining fiber (PMF). The fiber is PANDA type and is the 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 loose tube jacketed fiber 900 μm in diameter. Figure 1 shows the orientation of polarization in the fiber.

Agere Systems’ optoelectronic components are being qualified to rigorous internal standards that are consistent with Telcordia Technologies † TR-NWT-000468. All design and manufacturing operations are ISO § 9001 certified. The module is being fully qualified for central office applications.

* Fujikura is a registered trademark of Fujikura Ltd.

†Telcordia Technologies is a trademark of Telcordia Technologies Inc.

§ISO is a registered trademark of The International Organization for Standardization.

CORE

STRESS ROD

PRINCIPLE POLARIZATION

AXIS

CLADDING

INNER COATING (SILICON & ACRYLATE)

OUTER COATING

1-771(C).a

Figure 1. Polarization-Maintaining Fiber

Pin Information

Table 1. Pin Descriptions

Pin	D2587P-Type	D2547P-Type
1	Thermistor	Thermistor
2	Thermistor	Thermistor
3	Laser dc Bias	Laser dc Bias
	(Cathode) (–)	(Cathode) (–)
4	Back-facet Monitor	Back-facet Monitor
	Anode (–)	Anode (–)
5	Back-facet Monitor	Back-facet Monitor
	Cathode (+)	Cathode (+)
6	TEC (+)1	TEC (+)1
7	TEC (–)1	TEC (–)1
8	Case Ground	Case Ground
9	λ Photodiode 2 Anode	Case Ground
10	λ Photodiode 1 Anode	Case Ground
11	Laser Anode (+) 2	Laser Anode (+) 2
12	RF Laser Input	RF Laser Input
	Cathode (–)	Cathode (–)
13	Laser Anode (+) 2	Laser Anode (+) 2
14	NC	Case Ground

1.A positive current through the thermoelectric heat pump cools the laser.

2.Both leads should be grounded for optimum performance.

2	Agere Systems Inc.

Data Sheet, Rev. 2

Wavelength-Selected, High-Power D2587P-Type (with Wavelength

July 2001

Locker)/D2547P-Type Isolated DFB Laser Modules

Description (continued)

7

6

5

4

3

2

1

–

+

–

–

+

L1

TH

TEC

140 nH

10 kΩ

				R1	ISOLATOR
	PACKAGE			20 Ω
	GROUNDS					NC
			+	–	+
8	9	10	11	12	13	14

1-567

Top view.

Figure 2. D2547P Circuit Schematic

			7				6				5							4		3		2		1
							TEC																	RTH
																				RFC
													PDPOWER
																								PM FIBER PIGTAIL
							PDWAVE				PDWAVE									LD		RRF
			8				9				10							11		12		13		14
																										1-1130(F)

Figure 3. D2587P Circuit Schematic

Block Diagram

LASER MODULE

DUAL		ISOLATOR AND
ETALON		FIBER COUPLING
	DFB	OPTICS
	SILICON SUBMOUNT
THERMISTOR	THERMOELECTRIC COOLER

			EEPROM
A TO D
CONVERTER

D TO A MICROPROCESSOR CONVERTER

SUGGESTED

ELECTRONICS MODULE (CUSTOMER SUPPLIED)

VOLTAGE PROPORTIONAL TO WAVELENGTH VOLTAGE PROPORTIONAL TO OPTICAL POWER VOLTAGE PROPORTIONAL TO TEMPERATURE

1-1129(F)

Agere Systems Inc.

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Wavelength-Selected, High-Power D2587P-Type (with Wavelength	Data Sheet, Rev. 2
Locker)/D2547P-Type Isolated DFB Laser Modules	July 2001

Absolute Maximum Ratings

Stresses in excess of the absolute maximum ratings can cause permanent damage to the device. These are absolute 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	Min	Max	Unit
Laser Reverse Voltage	VRLMAX	—	2	V
dc Forward Current	IFLMAX	—	225	mA
Operating Case Temperature Range	TC	–25	70	°C
Storage Case Temperature Range*	Tstg	–40	70	°C
Photodiode Reverse Voltage	VRPDMAX	—	10	V
Photodiode Forward Current	IFPDMAX	—	2	mA

* Does not apply to shipping container.

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.

Electrostatic Discharge

CAUTION: This device is susceptible to damage as a result of electrostatic discharge. Take proper precautions during both handling and testing. Follow guidelines such as JEDEC Publication No. 108-A (Dec. 1988).

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 kΩ, capacitance = 100 pF) is widely used and, therefore, can be used for comparison purposes. The HBM ESD threshold presented here was obtained using these circuit parameters:

Parameter	Value	Unit
Human-body Model	>400	V

Mounting Instructions

The minimum fiber bend radius is 1.0 in. (25.4 mm)

To avoid degradation in performance, mount the module 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 thermal conductive grease is optional; however, thermal performance can be improved by up to 5% if conductive 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)

0.118

(3.00)

0.031 (0.79)							0.086
								(2.18)

0.140

(3.56)

0.129 (3.28) R

0.041 (1.04)

1-532(C)

Note: Dimensions are in inches and (millimeters).

Figure 4. Fillister Head Screw

4	Agere Systems Inc.

Data Sheet, Rev. 2	Wavelength-Selected, High-Power D2587P-Type (with Wavelength
July 2001	Locker)/D2547P-Type Isolated DFB Laser Modules

Characteristics

Minimum and maximum values are testing requirements. Typical values are device characteristics and are results of engineering evaluations; they are for information purposes only and are not part of the testing requirements.

Table 2. D2587-Type Electrical Characteristics (at 25 °C laser temperature)

Parameter	Symbol	Test Conditions	Min	Typ	Max	Unit
Threshold Current	ITH	—	—	15	40	mA
Drive Current	—	L F = 20 mW	—	—	165	mA
Laser Forward Voltage	VLF	LF = 20 mW (CW)	—	2	2.5	V
Monitor Reverse-bias Voltage*	VRMON	—	3	5	10	V
Monitor Current:		PO = 20 mW (CW)
Back-facet Monitor	IRMON		0.003	—	0.06	mA
λ Photodiode 1	IλPD1		0.003	—	0.06	mA
λ Photodiode 2	IλPD2		0.003	—	0.06	mA
Monitor Dark Current	ID	IF = 0, VRMON = 5 V	—	0.01	0.1	μA
Input Impedance	ZIN	—	—	25	—	Ω
Filter Slope	—	—	0.5	—	8	/nm
Frequency Capture Range	—	Measured from λITU	15	—	—	GHz
		toward increasing λ and
		decreasing λ
Thermistor Current	ITC	—	10	—	100	μA
Resistance Ratio†	—	—	9.1	9.6	10.1	—
Thermistor Resistance	RTH	TL = 25 °C	9.5	—	10.5	k Ω
Laser Submount Temperature	TSET	—	20	—	35	°C
TEC Current	ITEC	TL = 25 °C, T C = 70 °C	—	—	1.7	A
TEC Voltage	VTEC	TL = 25 °C, T C = 70 °C	—	—	2.8	V
TEC Capacity	T	TC = 70 °C	—		50	°C

* Standard operating condition is 5.0 V reverse bias.

† Ratio of thermistor resistance at 0 °C to thermistor resistance at 50 °C.

Table 3. D2587-Type Optical Characteristics (at 25 °C laser temperature)

Parameter	Symbol	Test Conditions	Min	Typ	Max	Unit
Peak Optical Output Power	PP	—	20.0	—	—	mW
Center Wavelength*	λC	TL = TSET	1528.77	—	1610.06	nm
(See Ordering Information, page 9.)		λC = λITU ± 0.1 nm
Line Width (3 dB full width)	Δλ	CW, PF = 20.0 mW	—	2	10	MHz
Side-mode Suppression Ratio	SMSR	CW	35	45	—	dB
Relative Intensity Noise	RIN	CW, PF = 20 mW	—	—	–135	dB/Hz
		200 MHz < f < 10 GHz
Optical Isolation	—	T C = 0 °C to 75 °C	30	—	—	dB
Optical Polarization Extinction Ratio†	—	0 °C to 75 °C	20	—	—	dB
FM Efficiency	FM	fMOD = 30 kHz,	—	100	—	MHz/mA
		PF = 20 mW
Wavelength Drift (EOL)	ΔλC	Tested over	—	—	±2.5	GHz
		25-year lifetime

* Custom wavelengths available.

† The ST ®ferrule key is not aligned to slow axis of fiber. Connector is intended for testing purposes only.

Agere Systems Inc.

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