AGERE A1751A62RRSC10, A1751A62RRSC06, A1751A62RRFC10, A1751A62RRFC08, A1751A62RRFC06 Datasheet

A1751A DWDM Analog
Forward-Path or Return-Path Laser Modules

Data Sheet, Rev. 4

June 2001

Features

■

Higher temperature rating

■

Excellent linearity

■

Standard ITU wavelengths

■

Advanced analog chip design

■

Tested for forward and return path applications

■

Reduces equipment requirements in the hub

■

Exceeds

Telcordia Technologies

* 468 specifica-

tion.

Applications

■

Node capability

■

Narrow transmitter housing

■

Networks with limited fiber

■

Architectures using separate optical wavelengths
to carry targeted services

*

Telcordia Technologies

is a trademark of Telcordia Technologies,

Inc.

Description

The A1751A laser module is a dense wavelength­division multiplexing (DWDM) laser for analog appli­cations. It features a distributed-feedback (DFB) chip
that has been designed specifically for radio fre­quency (RF) applications. The A1751A 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 linear­ity minimizes degradation of the broadcast signals
caused by the quadrature amplitude modulation
(QAM) channels.

Wavelength-division multiplexing is being designed
into cable television architectures. DWDM, a method
for delivering targeted QAM signals to different loca­tions, allows multiple signal sets to be combined onto
a single strand of fiber for transmission from a head­end to a hub. At the hub, individual QAM signals can
be selected and combined with broadcast analog
channels. The versatile A1751A DWDM laser module
reduces cable network architecture fiber needs and
lessens equipment requirements in the hub.

The A1751A is available in a wide range of standard
ITU wavelengths. The lasers are offered as either for­ward-path (40 MHz—860 MHz) or return-path
(5 MHz—210 MHz) modules.

2

A1751A DWDM Analog Data Sheet, Rev. 4
Forward-Path or Return-Path Laser Modules June 2001

Agere Systems Inc.

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 operational sections of the data sheet. Exposure to absolute maximum ratings for extended
periods can adversely affect device reliability.

* The device can withstand continuous exposure to the specified limits without damage.

Characteristics

1. Tested in a 50 Ω resistively matched system.

2. Eight channel loading with 10% OMI and 40 km fiber length.

3. Measured at 42 MHz.

4. Measured at 553.25 MHz, 577.25 MHz, and 595.25 MHz.

5. Change in wavelength as case temperature is changed.

Parameter* Symbol Min Max Unit

Operating Case Temperature Range T

C

–40 85

°

C

Storage Temperature Range Tstg –40 85

°

C

Monitor Photodiode Reverse Voltage V

MPD

—10V

Laser Forward Current I

F

— 150 mA

Reverse Voltage (Laser) V

R

—2V

TEC Current I

TEC

—1.7A

RF Input Power P

RFIN

— 62 dBm V

Table 1. Key Characteristics

Parameter Symbol Conditions Min Typ Max Unit

Frequency Range:

1

Return Path
Forward Path

F —

5

40

—
—

210
860

MHz
MHz
MHz

Frequency Response:

1

5 MHz—210 MHz
40 MHz—860 MHz

—I

F

= 60 mA,

T

OP

= 25 °C —

—

±0.5
±0.5

—
—

dB
dB

RF Return Loss:

1

5 MHz—210 MHz
40 MHz—860 MHz

RL

RF

IF = 60 mA,

—
—

>16
>16

—
—

dB
dB

Optical Output Power P

O

IF = I

OP

6, 8, or

10

——mW

Laser Relative Intensity

Noise

RIN I

F

= I

TH

+ 70 mA,

T = 25 °C

—

<

–155 — dB/Hz

Composite Second Order

2, 3

CSO IF = IOP, OMI = 10% — — –50 dBc

Composite Triple Beat

2, 4

CTB IF = IOP, OMI = 10% — — –60 dBc

Available Wavelengths

λ

I

P

= IOP, T = T

OP

1527.94 — 1563.1 nm

Wavelength Drift

5

λ∆

I

F

= 60 mA,
T = T

OP,

T

C

varied from min—>max

— — 0.04 nm

Adiabatic Chirp FM I

F

= 60 mA,

T

OP

= 25 °C,

measured at 500 MHz

40 — 100 MHz/mA

Operating Case

Temperature Range

T

C

IF = I

OP

–40 — 85

°

C

3

Data Sheet, Rev. 4 A1751A DWDM Analog
June 2001 Forward-Path or Return-Path Laser Modules

Agere Systems Inc.

Characteristics

(continued)

1. Bias point at which all specifications apply.

2. For 10 mW output power. Minimum slope efficiency is lower f or lower-power lasers.

3. Chip temperature at which wavelength specification is met. Operating chip temperature is reported for each laser.

Electrical Schematics

Figure 1. A1751A Laser Schematic

Table 2. Additional Characteristics

Parameter Symbol Conditions Min Max Unit

Bias Current

1

I

B

BOL — 120 mA

Threshold Current I

TH

25 °C, BOL — 30 mA

Slope Efficiency

2

η I

P

= ITH + 20 and

I

TH

+ 60

0.10 — mW/mA

Monitor Photocurrent I

MON

IOP = 0 mA, VRM = 5 V,

T

OP

= 25 °C

10 200 µA/mW

Operating Chip Temperature

3

T

OP

IF = I

OP

18 35 °C

TEC Current I

TEC

–40 °C < T

C

< 85 °C,

T

OP

= 15 °C—35 °C,

I

F

= 60 mA

–1.5 1.5 A

TEC Voltage V

TEC

T

OP

= 15 °C—35 °C over T

C

–2.5 3.8 V

Thermistor Resistance R

TH

TOP = 25 °C — 10.5 kΩ

Optical Return Loss RL T

C

40 — dB

Side Mode Suppression Ratio SMSR I

F

= I

OP

30 — dB

1

2

3

4

5

6

7

14

13

12

11

10

9

8

CASE

GROUND

NC

(+)

(–)

(+)

(–)

TEC

(–)

(+)

CASE

GROUND

NC

ISOLATOR

(+)

1-1233(F)