AGERE A1750A62RRSC10, A1750A62RRSC08, A1750A62RRSC06, A1750A62RRFC10, A1750A62RRFC08 Datasheet

A1750A DWDM Analog
Forward-Path or Return-Path Laser Module

Data Sheet, Rev. 4

June 2001

Features

■

Low adiabatic chirp

■

Excellent linearity

■

Standard ITU wavelengths

■

Advanced analog chip design

■

Tested for forward-path or return-path applications

■

Reduces equipment requirements in the hub

■

Exceeds

Telcordia Technologies

* 468 specifica-

tion.

Applications

■

Networks with limited fiber

■

Architectures using separate optical wavelengths
to carry targeted services

*

Telcordia Technologies

is a trademark of Telcordia Technologies

Inc.

Description

The A1750A laser module is a dense wavelength­division multiplexing laser with a DFB chip designed
specifically for analog RF applications. The device
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 QAM channels.

Wavelength-division multiplexing (WDM) has gained
widespread acceptance in the telecommunications
market and is being designed into emerging cable
television network architectures. Dense WDM, 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 A1750A DWDM laser
module reduces cable network architecture fiber
requirements and lessen equipment requirements in
the hub.

The A1750A is available at a variety of standard ITU
wavelengths. The lasers are offered as either for­ward-path (40 MHz–860 MHz) or return-path mod­ules (5 MHz–210 MHz).

2

A1750A DWDM Analog Data Sheet, Rev. 4
Forward-Path or Return-Path Laser Module 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 system with 27 Ω series matching resistor.

2. Eight-channel loading, 10% OMI, 40 km fiber.

3. Measured at 42 MHz.

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

5. Consult an Agere Systems account manager for other wavelengths.

6. Change in wavelength as case temperature is changed.

Parameter* Symbol Min Max Unit

Operating Case Temperature Range T

C

–25 65

°

C

Storage Temperature Range Tstg –40 70

°

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

–1.5 1.5 A

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

Frequency Response:

1

5 MHz—210 MHz
40 MHz—860 MHz

|S21| 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

|S21| I

F

= 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

5

λ

I

P

= IOP, T = T

OP

1528 — 1563 nm

Wavelength Drift

6

∆λ

OP

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 Tem pera-

ture Range

T

C

IF = I

OP

–20 — 65

°

C

3

Data Sheet, Rev. 4 A1750A DWDM Analog
June 2001 Forward-Path or Return-Path Laser Module

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. A1750A Laser Schematic

Table 2. Additional Characteristics

Parameter Symbol Conditions Min Max Unit

Bias Current

1

(Operating Current) 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

15 35 °C

TEC Current I

TEC

–20 °C < T

C

< 65 °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 2 V

Thermistor Resistance R

TH

TOP = 25 °C 9.5 10.5 kΩ

Optical Return Loss ORL 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

(+)

1-1233F