Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsPMICsPMIC - laser controller Laser diode driver (LWL) TQFN 32 EP Surface-mount

General Description

The MAX3863 is designed for direct modulation of laser

diodes at data rates up to 2.7Gbps. An automatic

power-control (APC) loop is incorporated to maintain a

constant average optical power. Modulation compensa-

tion is available to increase the modulation current in

proportion to the bias current. The optical extinction

ratio is then maintained over temperature and lifetime.

The laser driver can modulate laser diodes at ampli-

tudes up to 80mA. Typical (20% to 80%) edge speeds

are 50ps. The MAX3863 can supply a bias current up

to 100mA. External resistors can set the laser output

levels.

The MAX3863 includes adjustable pulse-width control

to minimize laser pulse-width distortion. The device

offers a failure monitor output to indicate when the APC

loop is unable to maintain the average optical power.

The MAX3863 accepts differential CML clock and data

input signals with on-chip 50Ω termination resistors. If a

clock signal is available, an input data-retiming latch

can be used to reject input pattern-dependent jitter.

The laser driver is fabricated with Maxim’s in-house

second-generation SiGe process.

Applications

SONET and SDH Transmission Systems

WDM Transmission Systems

3.2Gbps Data Communications

Add/Drop Multiplexers

Digital Cross-Connects

Section Regenerators

Long-Reach Optical Transmitters

Features

♦ Single +3.3V Power Supply

♦ 58mA Power-Supply Current

♦ Up to 2.7Gbps (NRZ) Operation

♦ On-Chip Termination Resistors

♦ Automatic Power Control (APC)

♦ Compensation for Constant Extinction Ratio

♦ Programmable Modulation Current Up to 80mA

♦ Programmable Bias Current Up to 100mA

♦ 50ps Typical Rise/Fall Time

♦ Pulse-Width Adjustment Circuit

♦ Selectable Data-Retiming Latch

♦ Failure Detector

♦ Mark-Density Monitor

♦ Current Monitors

♦ ESD Protection

MAX3863

2.7Gbps Laser Driver with Modulation

Compensation

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Maxim Integrated Products

RTEN

BIASMAX

MODSET

MODCOMP

BIASMON

MODMON

APCSET

APCFILT1

APCFILT2

PWC+

PWC-

MK+

MK-

FAIL

*THE EXPOSED PAD MUST BE SOLDERED TO GND ON THE CIRCUIT BOARD.

*EP

BIAS

MOD

MODN

CLK-

CLK+

DATA-

DATA+

MAX3863

24 MDMON

TOP VIEW

TQFN-EP

QFN-EP

Pin Configuration

Ordering Information

19-2281; Rev 4; 11/08

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,

or visit Maxim’s website at www.maxim-ic.com.

PART TEMP RANGE PIN-PACKAGE

MAX3863ETJ+ -40°C to +85°C 32 TQFN-EP*

MAX3863EGJ -40°C to +85°C 32 QFN-EP*

Denotes a lead-free/RoHS-compliant package.

EP = Exposed pad.

Summary of content (15 pages)

PAGE 1
9-2281; Rev 4; 11/08 2.7Gbps Laser Driver with Modulation Compensation The MAX3863 is designed for direct modulation of laser diodes at data rates up to 2.7Gbps. An automatic power-control (APC) loop is incorporated to maintain a constant average optical power. Modulation compensation is available to increase the modulation current in proportion to the bias current. The optical extinction ratio is then maintained over temperature and lifetime.
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MAX3863 2.7Gbps Laser Driver with Modulation Compensation ABSOLUTE MAXIMUM RATINGS Supply Voltage VCC...............................................-0.5V to +5.0V DATA+, DATA- and CLK+, CLK- ....(VCC - 1.5V) to (VCC + 0.5V) RTEN, EN, BIAS, MK+, MK-, PWC+, PWCMODMON, BIASMON, MDMON, MODCOMP, APCFILT1, APCFILT2, BIASMAX, MODSET, APCSET Voltage ......................................-0.5V to (VCC + 0.5V) MOD, MODN Voltage .......................................0 to (VCC + 1.5V) MOD, MODN Current...............
PAGE 3
2.7Gbps Laser Driver with Modulation Compensation (VCC = +3.15V to +3.6V, TA = -40°C to +85°C. Typical values are at VCC = +3.3V, IBIAS = 50mA, IMOD = 40mA, TA = +25°C, unless otherwise noted.) (Notes 1, 9) PARAMETER Single-Ended Input (DC-Coupled) Single-Ended Input (AC-Coupled) Differential Input Swing SYMBOL VIS CONDITIONS Input Data Rate RLIN Turn-Off Delay from EN MAX At low VCC - 1.0 VCC - 0.1 At high VCC + 0.05 VCC + 0.4 At low VCC 0.4 VCC 0.05 DC-coupled 0.2 2.0 AC-coupled 0.
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Typical Operating Characteristics (TA = +25°C, unless otherwise noted. See Typical Operating Circuit.) OPTICAL EYE DIAGRAM (IMOD = 40mA, DATA RATE = 2.5Gbps, PATTERN 213 - 1 + 80CID) OPTICAL EYE DIAGRAM (IMOD = 40mA, DATA RATE = 3.2Gbps, PATTERN 213 - 1 + 80CID) MAX3863 toc03a 58ps/div 58ps/div SUPPLY CURRENT (ICC) vs.TEMPERATURE (EXCLUDES BIAS AND MODULATION CURRENTS) 65 60 55 50 14 12 3.2Gbps 10 8 2.
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2.7Gbps Laser Driver with Modulation Compensation MODULATION CURRENT vs. MODULATION SET RESISTOR 180 160 VMODMON (mV) 10 100 120 IBIAS (mA) IMOD (mA) 140 MAX3863 toc09 1000 MAX3863 toc08 200 MAX3863 toc07 100 BIAS CURRENT vs. BIASMAX SET RESISTOR MODULATION MONITOR VOLTAGE vs. MODULATION CURRENT 100 80 10 60 40 20 1 1 10 100 5 20 35 50 0.1 80 65 10 1 100 RMODSET (kΩ) IMOD (mA) RBIASMAX (kΩ) BIAS MONITOR VOLTAGE vs. BIAS CURRENT MONITOR DIODE CURRENT vs.
PAGE 6
2.7Gbps Laser Driver with Modulation Compensation MAX3863 Pin Description 6 PIN NAME FUNCTION 1, 4, 5, 8, 14, 19, 22, 27 VCC 2 DATA+ 3 DATA- Complementary Data Input, with On-Chip Termination 6 CLK+ Clock Input for Data Retiming, with On-Chip Termination 7 CLK- Complementary Clock Input for Data Retiming, with On-Chip Termination 9 APCSET Positive Supply Voltage Data Input, with On-Chip Termination Monitor Diode Current Set Point 10 APCFILT1 APC Loop Filter Capacitor.
PAGE 7
2.7Gbps Laser Driver with Modulation Compensation MAX3863 VCC A - TOKO FSLB2520-330K B - MURATA BLM11HA601SPT A A B B VCC PATTERN GENERATOR VCC DATA+ 50Ω DATA+ DATA- 50Ω DATAMAX3863 VCC 50Ω MODN 0.1μF VCC CLK+ 25Ω 0.1μF APCFILT1 CLK+ OSCILLOSCOPE 50Ω MOD 50Ω 50Ω VCC CLK- 50Ω CLK- BIAS RTEN EN 15Ω Figure 1. AC Characterization Detailed Description The MAX3863 laser driver has two main components: a high-speed modulation driver and a biasing block with APC.
PAGE 8
MAX3863 2.7Gbps Laser Driver with Modulation Compensation the output-enable must be true to enable bias and modulation currents. APC Loop Enable The APC loop is enabled when an external capacitor is placed between the APCFILT1 and APCFILT2 pins. This capacitor sets the time constant of the APC loop. To open the APC loop, the APCFILT1 pin is shorted to ground. This shorts the feedback from the monitor diode and causes the bias current to rise to the maximum value set by the BIASMAX pin.
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MAX3863 2.7Gbps Laser Driver with Modulation Compensation VCC VCC RTEN 25Ω VCC MODN 1 MUX DATA DATA D D Q MOD 0 IMOD CD RD CLK CLK BIAS VCC APCFILT1 5Ω BIASMON x200 CURRENT MONITOR Vbg IMODS IMD x5 Vbg CAPC MD ∑ + IMODC IBIAS APCFILT2 x200 MODMON MDMON VCC 500pF Vbg - RMODSET RMODCOMP RBIASMAX RAPCSET EN Figure 3. Functional Diagram programming resistor. See the IBIASMAX vs.
PAGE 11
2.7Gbps Laser Driver with Modulation Compensation IMOD1 MAX3863 LASER POWER VCC IMOD2 P1 T1 T2 50Ω 50Ω DATA+ PAVG DATA- P0 IBIAS1 IBIAS2 LASER CURRENT Figure 4. Laser Power vs. Current for a Change in Temperature I MOD = I MODS + K × I BIAS 1.2V I MODS = 200 × R MODSET 5 K = 200 × 500 + R MODCOMP GND Figure 5.
PAGE 12
2.7Gbps Laser Driver with Modulation Compensation MAX3863 Typical Operating Circuit VCC VCC RBIASMON 100Ω DATA- 50Ω DATA- VCC MODN 25Ω MOD 25Ω 0.1μF VCC MAX3863 0.1μF APCSET BIASMAX MD RAPCSET CAPC 0.
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2.7Gbps Laser Driver with Modulation Compensation REVISION NUMBER REVISION DATE 0 1/02 1 10/02 2 5/03 3 4 1/06 11/08 DESCRIPTION PAGES CHANGED Initial release. — Corrected bond pad 24 to MODMON in the Chip Topography. 13 Added the PKG CODE column to the Ordering Information table. 1 Updated the package outline drawing in the Package Information section. 15 Added the TQFN package to the Ordering Information table and Absolute Maximum Ratings.