MAXIM MAX3869 Technical data

General Description

The MAX3869 is a complete, single +3.3V laser driver for SDH/SONET applications up to 2.5Gbps. The device accepts differential PECL data and clock inputs and provides bias and modulation currents for driving a laser. A synchronizing input latch can be used (if a clock signal is available) to reduce jitter.

An automatic power control (APC) feedback loop is incorporated to maintain a constant average optical power over temperature and lifetime. The wide modulation current range of 5mA to 60mA and bias current of 1mA to 100mA are easy to program, making this product ideal for use in various SDH/SONET applications.

The MAX3869 also provides enable control, two current monitors that are directly proportional to the laser bias and modulation currents, and a failure-monitor output to indicate when the APC loop is unable to maintain the average optical power. The MAX3869 is available in 32-pin TQFP and small 32-pin QFN packages as well as dice.

Applications

SONET/SDH Transmission Systems

Add/Drop Multiplexers

Digital Cross-Connects

Section Regenerators

2.5Gbps Optical Transmitters

Features

♦ Single +3.3V or +5V Power Supply

♦ 64mA Supply Current at +3.3V

♦ Programmable Bias Current from 1mA to 100mA

♦ Programmable Modulation Current from

5mA to 60mA

♦ Bias Current and Modulation Current Monitors

♦ 87ps Rise/Fall Time

♦ Automatic Average Power Control with Failure

Monitor

♦ Complies with ANSI, ITU, and Bellcore

SDH/SONET Specifications

♦ Enable Control

*Exposed pad. **Package Code: G3255-1 ***Dice are designed to operate over this range, but are tested and

guaranteed at TA= +25°C only. Contact factory for availability. +Denotes lead-free package.

Ordering Information

MAX3869

+3.3V, 2.5Gbps SDH/SONET Laser Driver

with Current Monitors and APC

________________________________________________________________ Maxim Integrated Products 1

EVALUATION KIT

AVAILABLE

124Ω 124Ω

SERIALIZER

WITH

CLOCK GEN.

124Ω

23Ω

LD

25Ω

+3.3V

0.056µF

0.01µF

BIASMON

MODMON

+3.3V

1000pF

BIASMAX

LATCH

ENABLE

FAIL

MODSET

APCSET

APCFILT

CLK-

CLK+

DATA-

DATA+

FERRITE BEAD

OUT+

BIAS

MD

OUT-

CAPC

124Ω

84.5Ω 84.5Ω 84.5Ω84.5Ω

MAX3869

MAX3890

Typical Application Circuit

19-1570; Rev 4; 1/05

Pin Configuration appears at end of data sheet.

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

PART TEMP RANGE PIN-PACKAGE

MAX3869EHJ -40°C to +85°C 32 TQFP-EP*

MAX3869EHJ+ -40°C to +85°C 32 TQFP-EP*

MAX3869EGJ -40°C to +85°C 32 QFN**

MAX3869E/D -40°C to +85°C Dice***

MAX3869

+3.3V, 2.5Gbps SDH/SONET Laser Driver with Current Monitors and APC

2 _______________________________________________________________________________________

IMD= 1mA

IMD= 18µA

90

ENABLE = low (Note 4)

APC open loop

(Note 3)

900

(Note 2)

(Note 5)

Sourcing 50µA

ENABLE, LATCH

(Note 6)

ENABLE, LATCH

I

BIAS

= 100mA

APC open loop

Figure 1

PECL compatible

Sinking 100µA

CONDITIONS

%

-15 15

Monitor-Diode Bias Absolute Accuracy

ppm/°C

-480 50 480

Monitor-Diode Bias Setpoint Stability

µA

18 1000

I

MD

Monitor-Diode DC Current Range

V

1.5

Monitor-Diode Reverse Bias Voltage

V

0.1 0.44

TTL Output Low Voltage FAIL

µA

100

I

BIAS-OFF

Bias Off-Current

mA

1 100

I

BIAS

mA

64 112

I

CC

Supply Current

Bias Current Range

V

2.4 VCC- 0.3 V

CC

TTL Output High Voltage FAIL

V

0.8

TTL Input Low Voltage

V

2.0

TTL Input High Voltage

µA

-1 10

I

IN

Clock and Data Input Current

ppm/°C

230

Bias-Current Stability

%

-15 15

(Note 5)Bias-Current Absolute Accuracy

mVp-p

200 1600

V

ID

Differential Input Voltage

V

VCC- VCC- VCC-

1.49 1.32 V

ID

/4

V

ICM

Common-Mode Input Voltage

UNITSMIN TYP MAXSYMBOLPARAMETER

DC ELECTRICAL CHARACTERISTICS

(VCC= +3.14V to +5.5V, TA= -40°C to +85°C. Typical values are at VCC= +3.3V, I

MOD

= 30mA, I

BIAS

= 60mA, TA= +25°C, unless

otherwise noted.) (Note 1)

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

Supply Voltage, VCC............................................. -0.5V to +7.0V

Current into BIAS ...........................................-20mA to +150mA

Current into OUT+, OUT- ................................-20mA to +100mA

Current into MD.....................................................-5mA to +5mA

Voltage at DATA+, DATA-, CLK+, CLK-, ENABLE,

LATCH, FAIL, BIASMON, MODMON .....-0.5V to (V

CC

+ 0.5V)

Voltage at APCFILT, CAPC, MODSET,

BIASMAX, APCSET ...........................................-0.5V to +3.0V

Voltage at OUT+, OUT-.............................+1.5V to (V

CC

+ 1.5V)

Voltage at BIAS .........................................+1.0V to (V

CC

+ 0.5V)

Continuous Power Dissipation (TA= +85°C)

32-Pin TQFP-EP (derate 22.2mW/°C above +85°C) ..1444mW

32-Pin QFN (derate 20.84mW/°C above +85°C) .......1667mW

Storage Temperature Range .............................-65°C to +165°C

Operating Junction Temperature Range...........-55°C to +150°C

Processing Temperature (die) .........................................+400°C

Lead Temperature (soldering, 10s) .................................+300°C

ABSOLUTE MAXIMUM RATINGS

I

BIAS/IBIASMON

A/A

37

A

BIAS

BIASMON to I

BIAS

Gain

I

MOD/IMODMON

A/A

29

A

MOD

MODMON to I

MOD

Gain

I

BIAS

= 1mA

MAX3869

+3.3V, 2.5Gbps SDH/SONET Laser Driver

with Current Monitors and APC

_______________________________________________________________________________________ 3

AC ELECTRICAL CHARACTERISTICS

(V

CC

= +3.14V to +5.5V, load as shown in Figure 2, TA= -40°C to +85°C. Typical values are at VCC= +3.3V, I

MOD

= 30mA, TA= +25°C.)

(Note 7)

Note 1: Dice are tested at T

A

= +25°C only.

Note 2: Tested at R

MODSET

= 2.49kΩ, R

BIASMAX

= 1.69kΩ, excluding I

BIAS

and I

MOD

.

Note 3: Voltage on BIAS pin is (V

CC

- 1.6V).

Note 4: Both the bias and modulation currents will be switched off if any of the current set pins are grounded. Note 5: Accuracy refers to part-to-part variation. Note 6: Assuming that the laser to monitor-diode transfer function does not change with temperature. Guaranteed by design and

characterization.

Note 7: AC characteristics are guaranteed by design and characterization. Note 8: Measured with 622Mbps 0-1 pattern, LATCH = high. Note 9: PWD = (wider pulse - narrower pulse) / 2. Note 10: See Typical Operating Characteristics for worst-case distribution.

I

MOD

= 5mA

300

78

LATCH = high, Figure 3

20% to 80% (Note 8)

ps

69

(Note 8)

20% to 80% (Note 8)

ENABLE = low (Note 4)

I

MOD

= 60mA

(Note 5)

Jitter BW = 12kHz to 20MHz, 0-1 pattern

(Notes 8, 9)

CONDITIONS

t

R

Output Rise-Time ps

ps

p-p

720

Jitter Generation

ps

14 50

PWDPulse-Width Distortion

mA

560

I

MOD

Modulation-Current Range

ps

100

t

H

ps

100

t

SU

Input Latch Setup Time

Input Latch Hold Time

bits

80

Maximum Consecutive Identical Digits

ns

250

Enable and Start-Up Delay

%

±15

Output Aberrations

79

t

F

Output Fall- Time

µA

200

I

MOD-OFF

Modulation-Off Current

ppm/°C

-480 -8 480

Modulation-Current Stability

%

-15 15

Modulation-Current Absolute Accuracy

87 (Note 10)

UNITSMIN TYP MAXSYMBOLPARAMETER

MAX3869EHJ

MAX3869E/D

MAX3869EHJ

MAX3869E/D

Figure 1. Required Input Signal and Output Polarity

DATA+

DATA-

(DATA+) - (DATA-)

I

+

OUT

100mV MIN

800mV MAX

200mVp-p MIN

1600mVp-p MAX

I

MOD

MAX3869

+3.3V, 2.5Gbps SDH/SONET Laser Driver with Current Monitors and APC

4 _______________________________________________________________________________________

Figure 3. Setup/Hold Time Definition

Figure 2. Output Termination for Characterization

Typical Operating Characteristics

(V

CC

= +3.3V, load as shown in Figure 2, TA= +25°C, unless otherwise noted.)

EYE DIAGRAM

(2.488Gbps, 1300nm FP LASER,

1.87GHz FILTER, 32 TQFP-EP)

MAX3869-01

48ps/div

MITSUBISHI ML725C8F LASER DIODE

0

5

15

10

20

25

84

83

87

32 TQFP-EP I

MOD

= 30mA

MEAN = 87.3ps σ = 1.6ps

88 90

89

8685

91

92

TYPICAL DISTRIBUTION OF FALL TIME

MAX3869-02

FALL TIME (ps)

PERCENT OF UNITS (%)

0

5

20

15

10

30

25

35

114.5

113

119

32 TQFP-EP I

MOD

= 60mA

V

CC

= 3.14V

T

A

= +85°C

MEAN = 119.1ps σ = 2.0ps

120.5 123.5

122

117.5116

125

126.5

DISTRIBUTION OF FALL TIME

(WORST-CASE CONDITIONS)

MAX3869-03

FALL TIME (ps)

PERCENT OF UNITS (%)

V

CC

t

= 402ps

CLK

A

B

MAX3869

OUT-

OUT+

BIAS

+

I

OUT

15Ω

V

CC

A, B ARE SMD FERRITE BEADS:

A

B = BLM11A601S MURATA ELECTRONICS A = BLM21A102S MURATA ELECTRONICS

B

0.056µF

50Ω

25Ω

OSCILLOSCOPE

50Ω

CLK

DATA

t

SU

t

H

MAX3869

+3.3V, 2.5Gbps SDH/SONET Laser Driver

with Current Monitors and APC

_______________________________________________________________________________________ 5

)

Typical Operating Characteristics (continued)

(V

CC

= +3.3V, load as shown in Figure 2, TA= +25°C, unless otherwise noted.)

ELECTRICAL EYE DIAGRAM

= 30mA, 213-1 +80 CID, 32 TQFP-EP)

(I

MOD

250mV/div

I

120

100

80

(mA)

60

BIASMAX

I

40

20

0

BIASMAX

110

R

100ps/div

vs. R

BIASMAX

(kΩ

100

300

MAX3869-04

MAX3869-07

ELECTRICAL EYE DIAGRAM

= 60mA, 213-1 +80 CID, 32 TQFP-EP)

(I

MOD

400mV/div

100ps/div

I

vs. R

100

90

80

70

60

(mA)

50

MOD

I

40

30

20

10

0

1 10 100

MOD

R

MODSET

(kΩ

MAX3869-05

MAX3869-08

8.0

RANDOM JITTER vs. I

7.5

7.0

6.5

6.0

5.5

5.0

4.5

RANDOM JITTER (psp-p)

4.0

3.5

3.0 5 15202510 30 35 40 45 50

I

(mA)

MOD

IMD vs. R

R

APCSET

(kΩ

1.2

1.1

1.0

0.9

0.8

0.7

(mA)

0.6

MD

I

0.5

0.4

0.3

0.2

0.1

0

0.1 1 10 100

MOD

MAX3869-06

MAX3869-09

SUPPLY CURRENT vs. TEMPERATURE

, I

(EXCLUDE I

100

90

VCC = +5.5V

80

70

60

50

40

30

SUPPLY CURRENT (mA)

20

10

0

-40 -15 10 35 60 85

BIAS

TEMPERATURE (°C)

, 25Ω LOAD)

MOD

VCC = +3.14V

MAX3869-10

)

BIASMON

/I

BIAS

GAIN (I

BIAS-CURRENT MONITOR GAIN

vs. TEMPERATURE

50

I

= 100mA, I

40

30

20

10

0

-40 -15 10 35 60 85

BIAS

I

= 10mA, I

BIAS

TEMPERATURE (°C)

MOD

= 50mA

= 10mA

MAX3869-11