Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsPMICsPMIC - laser controller Laser diode driver (LWL) TQFN 24 Surface-mount

General Description

The MAX3643 burst-mode laser driver provides bias and

modulation current drive for PON burst-mode ONT appli-

cations. It is specifically designed for use with a low-cost

external controller for the APC (and if desired, AMC) loop.

A high-speed differential burst-enable input enables the

driver to switch the laser from a dark (output off) condition

to full on-condition in less than 2ns. When BEN is inac-

tive, typical modulation and bias currents are 5µA each.

Laser modulation current can be set from 10mA to

85mA and bias current can be set from 1mA to 70mA

using the MODSET and BIASSET inputs. A sample-and-

hold circuit is provided to capture the monitor diode

output during short PON bursts, if needed, and the BEN

high-speed signal is mirrored on an LVCMOS output to

be used by the controller operating the APC/AMC loop.

The MAX3643 burst-mode laser driver is packaged in a

4mm x 4mm, 24-pin thin QFN package. It operates from

-40°C to +85°C.

Applications

A/B/G/XGPON ONT Modules Up to 2.5Gbps

1.25Gbps IEEE EPON ONT Modules

Features

♦ 10mA to 85mA Modulation Current

♦ 1mA to 70mA Bias Current

♦ Monitor Diode Sample and Hold

♦ 45ps Output Transition Time

♦ 2ns Turn-On/-Off Time

♦ Reference Voltage Generator

♦ LVPECL High-Speed Inputs (Data, Burst Enable)

155Mbps to 2.5Gbps Burst-Mode Laser Driver

MAX3643

For pricing, delivery, and ordering information, please contact Maxim Direct at

1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com.

EVALUATION KIT AVAILABLE

Ordering Information

OUT-

BMD

MON1

FILTER+3.3V

3.3V

10nH

75Ω

1kΩ

BENOUT

BIASSET

MODSET

VBSET

+3.3V

3.3V

VMSET

3kΩ

IMAX

1kΩ

BCMON

1kΩ

IN-

IN+

SERIAL

DATA

SOURCE

GND

VREF

BEN

BIAS

MOD

130Ω130Ω

15Ω

82Ω82Ω

= 50Ω

3.3V

BEN-

BEN+

BURST

CONTROL

130Ω130Ω

82Ω82Ω

= 50Ω

MAX3643

PON TRIPLEXER AND SFP

CONTROLLER

DS1875

15Ω

OUT+

5.6Ω

BIAS+

5.6Ω

BIAS-

10Ω

MDOUT

MDIN

27pF

10pF

Typical Application Circuit

19-3848; Rev 4; 12/12

Denotes a lead(Pb)-free/RoHS-compliant package.

EP = Exposed paddle.

Pin Configuration appears at end of data sheet.

PART TEMP RANGE PIN-PACKAGE

MAX3643ETG -40°C to +85°C 24 TQFN-EP*

MAX3643ETG+ -40°C to +85°C 24 TQFN-EP*

Summary of content (15 pages)

PAGE 1
EVALUATION KIT AVAILABLE MAX3643 155Mbps to 2.5Gbps Burst-Mode Laser Driver General Description Features The MAX3643 burst-mode laser driver provides bias and modulation current drive for PON burst-mode ONT applications. It is specifically designed for use with a low-cost external controller for the APC (and if desired, AMC) loop. A high-speed differential burst-enable input enables the driver to switch the laser from a dark (output off) condition to full on-condition in less than 2ns.
PAGE 2
MAX3643 155Mbps to 2.5Gbps Burst-Mode Laser Driver ABSOLUTE MAXIMUM RATINGS Supply Voltage VCC ..............................................-0.5V to +4.0V Current into BIAS-, BIAS+, OUT-, OUT+ .......-20mA to +150mA Voltage at VMSET, VBSET, IN+, IN-, BEN+, BEN-, EN, MDIN, MDOUT, BENOUT, BCMON ...................-0.5V to (VCC + 0.5V) Voltage at MODSET, BIASSET, VREF, IMAX ........-0.5V to +3.0V Voltage at OUT-, OUT+, BIAS-, BIAS+ .....+0.3V to (VCC + 0.
PAGE 3
MAX3643 155Mbps to 2.5Gbps Burst-Mode Laser Driver ELECTRICAL CHARACTERISTICS (continued) (VCC = 3.0V to 3.6V, TA = -40°C to +85°C. Typical values are at VCC = 3.3V, TA = +25°C, IBIAS = 20mA, IMOD = 30mA, unless otherwise noted.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS BIASSET Current Gain Stability 5mA IBIAS 70mA (Note 13) -4.4 +4.4 % BIASSET Current Gain Linearity 5mA IBIAS 70mA (Note 14) -3.75 +3.
PAGE 4
MAX3643 155Mbps to 2.5Gbps Burst-Mode Laser Driver ELECTRICAL CHARACTERISTICS (continued) (VCC = 3.0V to 3.6V, TA = -40°C to +85°C. Typical values are at VCC = 3.3V, TA = +25°C, IBIAS = 20mA, IMOD = 30mA, unless otherwise noted.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN Final value measured after 10μs (MDOUT - MDIN), burst width > 576ns Sampling Error TYP MAX UNITS 3 ±14 mV 1.235 1.295 V BANDGAP VOLTAGE REFERENCE SPECIFICATIONS VREF Output RL > 10k , CL < 50pF 1.
PAGE 5
MAX3643 155Mbps to 2.5Gbps Burst-Mode Laser Driver Typical Operating Characteristics (Typical values are at VCC = 3.3V, TA = +25°C, data pattern = 27-1 PRBS + 80 ones + 27-1 PRBS + 80 zeros, unless otherwise noted.) MAX3643 toc01 EXCELIGHT SLT2886-LR LASER AVERAGE OPTICAL POWER = -6dBm EXTINCTION RATIO = 15dB MASK MARGIN = 49% OPTICAL EYE DIAGRAM (1.24416Gbps, 933MHz FILTER, PATTERN = 223 - 1 PRBS) OPTICAL EYE DIAGRAM (622.
PAGE 6
MAX3643 155Mbps to 2.5Gbps Burst-Mode Laser Driver Typical Operating Characteristics (continued) (Typical values are at VCC = 3.3V, TA = +25°C, data pattern = 27-1 PRBS + 80 ones + 27-1 PRBS + 80 zeros, unless otherwise noted.) RANDOM JITTER vs. MODULATION AMPLITUDE DETERMINISTIC JITTER vs. MODULATION AMPLITUDE 1.1 1.0 RANDOM JITTER (psRMS) 24 21 18 15 12 9 MAX3643 toc08 27 DJ (psP-P) 1.2 MAX3643 toc07 30 0.9 0.8 0.7 0.6 0.5 0.4 6 3 0.3 0 0.
PAGE 7
MAX3643 155Mbps to 2.5Gbps Burst-Mode Laser Driver Typical Operating Characteristics (continued) (Typical values are at VCC = 3.3V, TA = +25°C, data pattern = 27-1 PRBS + 80 ones + 27-1 PRBS + 80 zeros, unless otherwise noted.) IBIAS + IMOD CURRENT THRESHOLD vs. RIMAX IBIAS vs.
PAGE 8
MAX3643 155Mbps to 2.5Gbps Burst-Mode Laser Driver Pin Description PIN NAME 1 VCCA 2 IN+ Noninverted Data Input, LVPECL Compatible 3 IN- Inverted Data Input, LVPECL Compatible Analog Supply Voltage 4 VCCS 5 BEN+ Noninverted Burst-Enable Input, LVPECL Compatible 6 BEN- Inverted Burst-Enable Input, LVPECL Compatible 7 BENOUT 8 EN 9 BCMON Signal Supply Voltage Burst-Enable Output, LVCMOS. Signal replicates BEN input. Enable Input LVCMOS. Active low enables BIAS± and OUT± outputs.
PAGE 9
MAX3643 155Mbps to 2.5Gbps Burst-Mode Laser Driver VCC LP RP 15Ω OUT+ MAX3643 RD OUT- IN+ RCOMP RD BIAS+ CCOMP LVPECL IN- BIAS- 10Ω VCC BEN+ LVPECL BENCMOS BENOUT IMAX LIMIT LIMIT VCC VCC MDIN CMOS EN I1 IM = 88 x I1 IB = 88 x I2 I2 MDOUT VCC IBCMON = IB x 0.014 1.2V RMOD VREF VMSET MODSET VBSET RBIAS BIASSET BCMON Figure 1.
PAGE 10
MAX3643 155Mbps to 2.5Gbps Burst-Mode Laser Driver Detailed Description The MAX3643 laser driver includes a bias current generator, bias current monitor, modulation current generator, laser drive outputs, and monitor diode sample and hold. LVPECL-compatible inputs are provided for both high-speed data and burst enable. The high-speed burst-enable input signal is replicated on an LVCMOS output for use by the controller.
PAGE 11
MAX3643 155Mbps to 2.5Gbps Burst-Mode Laser Driver BURST-ENABLE (BEN±) IN ≤ 125μs FOR BPON/GPON INTERNAL MDIN VOLTAGE SAMPLER BENOUT OUTPUT 3μs MDOUT < 2.56mV 1.2V 100μs Figure 2. Sample-and-Hold Timing Diagram Enable Input An LVCMOS input, EN, is provided to disable both bias and modulation currents under external control. The maximum time to disable laser current with the EN control is 375ns.
PAGE 12
MAX3643 155Mbps to 2.5Gbps Burst-Mode Laser Driver This approach can also be used for a conventional voltage DAC output, if desired. In all cases, the voltage at MODSET must be kept ≤ 1.4V, which limits the range of acceptable values for RMODSET depending on the maximum modulation current. VCC 130Ω Laser diode bias current is set in the same manner as modulation current.
PAGE 13
MAX3643 155Mbps to 2.5Gbps Burst-Mode Laser Driver Applications Information Running Burst-Enable Single-Ended VCC See Figure 5 for setting up the single-ended LVTTL or LVCMOS biasing for burst enable. Layout Considerations To minimize inductance, keep the connections between the MAX3643 output pins and laser diode as close as possible. Place a bypass capacitor as close as possible to each VCC connection. Take extra care to minimize stray parasitic capacitance on the BIAS and MDIN pins.
PAGE 14
MAX3643 155Mbps to 2.5Gbps Burst-Mode Laser Driver Pin Configuration TRANSISTOR COUNT: 2771 PROCESS: SiGe BiPOLAR BIAS- OUT+ 16 VCCO OUT17 BIAS+ VCCO TOP VIEW 18 15 14 13 GND 19 Package Information 12 MDIN MODSET 20 11 MDOUT VMSET 21 10 IMAX MAX3643 VREF 22 9 BCMON VBSET 23 8 EN 7 BENOUT *EP IN- 4 5 6 BEN- 3 VCCS 2 BEN+ 1 IN+ + VCCA BIASSET 24 Chip Information For the latest package outline information and land patterns, go to www.maximintegrated.com/packages.
PAGE 15
MAX3643 155Mbps to 2.5Gbps Burst-Mode Laser Driver Revision History REVISION NUMBER REVISION DATE 0 11/05 1 10/08 DESCRIPTION Initial release. Added “155Mbps to 2.5Gbps” to the data sheet/part title. PAGES CHANGED — All Updated the Applications section. 1 In the Operating Conditions table, changed the data rate from 1250Mbps to 2500Mbps. 2 In the Typical Operating Characteristics, added the Electrical Eye Diagram graph.