AGERE A1751A62RRSC10, A1751A62RRSC06, A1751A62RRFC10, A1751A62RRFC08, A1751A62RRFC06 Datasheet

Data Sheet, Rev. 4

June 2001

A1751A DWDM Analog

Forward-Path or Return-Path Laser Modules

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 specification.

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 for- ward-path (40 MHz—860 MHz) or return-path

(5 MHz—210 MHz) modules.

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.

A1751A DWDM Analog	Data Sheet, Rev. 4
Forward-Path or Return-Path Laser Modules	June 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 operational sections of the data sheet. Exposure to absolute maximum ratings for extended periods can adversely affect device reliability.

Parameter*	Symbol	Min	Max	Unit
Operating Case Temperature Range	TC	–40	85	°C
Storage Temperature Range	Tstg	–40	85	°C
Monitor Photodiode Reverse Voltage	VMPD	—	10	V
Laser Forward Current	IF	—	150	mA
Reverse Voltage (Laser)	VR	—	2	V
TEC Current	ITEC	—	1.7	A
RF Input Power	PRFIN	—	62	dBm V

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

Characteristics

Table 1. Key Characteristics

Parameter	Symbol	Conditions	Min	Typ	Max	Unit
Frequency Range:1	F	—				MHz
Return Path			5	—	210	MHz
Forward Path			40	—	860	MHz
Frequency Response:1	—	I F = 60 mA,
5 MHz—210 MHz		TOP = 25 °C	—	±0.5	—	dB
40 MHz—860 MHz			—	±0.5	—	dB
RF Return Loss:1	RLRF	IF = 60 mA,
5 MHz—210 MHz			—	>16	—	dB
40 MHz—860 MHz			—	>16	—	dB
Optical Output Power	PO	IF = IOP	6, 8, or	—	—	mW
			10
Laser Relative Intensity	RIN	IF = ITH + 70 mA,	—	< –155	—	dB/Hz
Noise		T = 25 °C
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	IP = IOP, T = TOP	1527.94	—	1563.1	nm
Wavelength Drift 5	λΔ	IF = 60 mA,	—	—	0.04	nm
		T = TOP,
		TC varied from min—>max
Adiabatic Chirp	FM	IF = 60 mA,	40	—	100	MHz/mA
		TOP = 25 °C,
		measured at 500 MHz
Operating Case	TC	IF = IOP	–40	—	85	°C
Temperature Range

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.

2	Agere Systems Inc.

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

Characteristics (continued)

Table 2. Additional Characteristics

Parameter	Symbol	Conditions	Min	Max	Unit
Bias Current1	IB	BOL	—	120	mA
Threshold Current	ITH	25 °C, BOL	—	30	mA
Slope Efficiency2	η	IP = ITH + 20 and	0.10	—	mW/mA
		ITH + 60
Monitor Photocurrent	IMON	IOP = 0 mA, VRM = 5 V,	10	200	μA/mW
		TOP = 25 °C
Operating Chip Temperature3	TOP	IF = IOP	18	35	°C
TEC Current	ITEC	–40 °C < TC < 85 °C,	–1.5	1.5	A
		TOP = 15 °C—35 °C,
		IF = 60 mA
TEC Voltage	VTEC	TOP = 15 °C—35 °C over T C	–2.5	3.8	V
Thermistor Resistance	RTH	TOP = 25 °C	—	10.5	k Ω
Optical Return Loss	RL	TC	40	—	dB
Side Mode Suppression Ratio	SMSR	IF = IOP	30	—	dB

1.Bias point at which all specifications apply.

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

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

Electrical Schematics

	1		NC	14
			ISOLATOR
	2			13	(+)
	3			12	(–)
(–)	4			11	(+)
(+)	5		NC	10
(+)	6		CASE	9
			GROUND
(–)	7	TEC	CASE	8
			GROUND
				1-1233(F)

Figure 1. A1751A Laser Schematic

Agere Systems Inc.

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