Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsPMICsPMIC - laser controller Laser diode driver (LWL) TQFN 16 EP Surface-mount

General Description

The MAX3736 is a compact, +3.3V multirate laser driver

for SFP/SFF applications up to 3.2Gbps. The device

accepts differential data and provides bias and modula-

tion currents for driving a laser. DC-coupling to the laser

allows for multirate applications, and reduces the num-

ber of external components.

The wide 5mA to 60mA (85mA AC-coupled) modulation

current range and 1mA to 100mA bias current make the

MAX3736 ideal for driving FP/DFB laser diodes in fiber-

optic modules. The laser current setting can be con-

trolled by a current DAC, a voltage DAC, or a resistor.

Very low power dissipation, small package size, and

reduced component count, make this part an ideal solu-

tion for SFP-module applications.

The MAX3736 is available in a small 3mm x 3mm, 16-pin

thin QFN package. It operates over a -40°C to +85°C

temperature range.

Applications

Gigabit Ethernet SFP/SFF Transceiver Modules

1G/2G Fibre-Channel SFP/SFF Transceiver

Modules

Multirate OC-3 to OC-48 FEC SFP/SFF

Transceiver Modules

10G Ethernet LX-4 Modules

Features

♦ Fully Compatible with SFP and SFF-8472

Specifications

♦ Programmable Modulation Current from 5mA to

60mA (DC-Coupled)

♦ Programmable Modulation Current from 5mA to

85mA (AC-Coupled)

♦ Programmable Bias Current from 1mA to 100mA

♦ 56ps Edge Transition Times

♦ 22mA (typ) Power-Supply Current

♦ Multirate Operation Up to 3.2Gbps

♦ On-Chip Pullup Resistor for DIS

♦ 16-Pin, 3mm × 3mm Thin QFN Package

MAX3736

3.2Gbps, Low-Power, Compact,

SFP Laser Driver

________________________________________________________________

Maxim Integrated Products

Ordering Information

+3.3V

SUPPLY FILTER

OUT-

OUT+

BIAS

BIASSET

MODSET

IN+

IN-

MOD-DEF1

MOD-DEF2

TX_DISABLE

LASER CONTROLLER

15Ω 56Ω

10Ω

8.2pF

0.01μF

FERRITE

BEAD

0.1μF

GND

DIS

SERDES

HOST FILTER

VCC_RX

BC_MON

50Ω

HOST BOARD SFP OPTICAL TRANSMITTER

MAX3736

Typical Application Circuit

19-3116; Rev 2; 9/10

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.

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

EP = Exposed pad.

PART TEMP RANGE PIN-PACKAGE

MAX3736ETE -40°C to +85°C 16 Thin QFN-EP*

MAX3736ETE+ -40°C to +85°C 16 Thin QFN-EP*

Pin Configuration appears at end of data sheet.

Summary of content (11 pages)

PAGE 1
9-3116; Rev 2; 9/10 3.2Gbps, Low-Power, Compact, SFP Laser Driver Features ♦ Fully Compatible with SFP and SFF-8472 Specifications The MAX3736 is a compact, +3.3V multirate laser driver for SFP/SFF applications up to 3.2Gbps. The device accepts differential data and provides bias and modulation currents for driving a laser. DC-coupling to the laser allows for multirate applications, and reduces the number of external components.
PAGE 2
MAX3736 3.2Gbps, Low-Power, Compact, SFP Laser Driver ABSOLUTE MAXIMUM RATINGS Operating Junction Temperature Range ..........-55°C to +150°C Storage Temperature Range .............................-55°C to +150°C Die Attach Temperature ..................................................+400°C Lead Temperature (soldering, 10s) .................................+300°C Soldering Temperature (reflow) Lead(Pb)-free...............................................................+260°C Containing lead(Pb) ..........
PAGE 3
.2Gbps, Low-Power, Compact, SFP Laser Driver (VCC = +2.97V to +3.63V, TA = -40°C to +85°C. Typical values are at VCC = +3.3V, IBIAS = 20mA, IMOD = 30mA, TA = +25°C, unless otherwise noted.) (Note 1) PARAMETER Modulation Current Range SYMBOL IMOD CONDITIONS MIN Current into OUT+, RL = 15 , VOUT+ and VOUT- 0.6V (DC-coupled) 5 Current into OUT+, RL = 15 , VOUT+ and VOUT- 2.
PAGE 4
MAX3736 3.2Gbps, Low-Power, Compact, SFP Laser Driver VOLTAGE VIN+ VCC VCC 100mV MIN 1200mV MAX VIN- 25Ω 26Ω OUT- (VIN+) - (VIN-) 30Ω 200mVP-P MIN 2400mVP-P MAX MAX3736 CURRENT IOUT+ 1.1pF OSCILLOSCOPE OUT+ IOUT+ IMOD Figure 1. Definition of Single-Ended Input Voltage Range SOURCE NOISE VOLTAGE SUPPLY Figure 2. Output Termination for Characterization HOST BOARD FILTER DEFINED BY SFP MSA MODULE TO LASER DRIVER VCC OPTIONAL 1μH 0.1μF 50Ω 130Ω 10μF OPTIONAL 0.1μF Figure 3.
PAGE 5
3.2Gbps, Low-Power, Compact, SFP Laser Driver BIAS CURRENT MONITOR GAIN vs. TEMPERATURE 70 80 MAX3736 toc06 EXCLUDES IBIAS AND IMOD 18 70 60 50 40 IMOD (mAP-P) GAIN (mA/A) 60 16 14 30 50 40 30 20 12 20 10 10 10 -15 10 35 60 85 0 -40 -15 10 35 60 85 1 RMODSET (kΩ) EDGE TRANSITION TIME vs. MODULATION AMPLITUDE BIAS CURRENT vs.
PAGE 6
Typical Operating Characteristics (continued) (Typical values are at VCC = 3.3V, IBIAS = 20mA, IMOD = 30mA, TA = +25°C, unless otherwise noted.) DETERMINISTIC JITTER vs. MODULATION CURRENT MAX3736 toc11 2.7Gbps 223-1 PRBS 50 DIFFERENTIAL S11 vs. FREQUENCY 0 MAX3736 toc10 60 -5 40 -10 IS11I (dB) DJ (psP-P) MAX3736 3.
PAGE 7
3.2Gbps, Low-Power, Compact, SFP Laser Driver MAX3736 DIS VCC VCC 82pF 16kΩ 7.2kΩ OUT+ 24kΩ 50Ω OUT- 50Ω IN+ IN- VCC VCC BIAS VCC x1 x85 x85 BC_MON 1.2V 1.2V MAX3736 BIASSET MODSET Figure 4. Functional Diagram Detailed Description The MAX3736 laser driver consists of three operational blocks: a bias current generator, a modulation current generator, and a high-speed modulation path. The laser-biasing block includes a monitor output for biassensing purposes.
PAGE 8
MAX3736 3.2Gbps, Low-Power, Compact, SFP Laser Driver High-Speed Modulation Driver The output stage is composed of a high-speed differential pair and a programmable modulation current source. The MAX3736 is optimized for driving a 15Ω load; the minimum instantaneous voltage required at OUT+ is 0.6V. Modulation current swings up to 60mA are possible. To interface with the laser diode, a damping resistor (RD) is required for impedance matching.
PAGE 9
3.2Gbps, Low-Power, Compact, SFP Laser Driver MAX3736 VCC VCC MAX3736 82pF PACKAGE 16kΩ MAX3736 PACKAGE VCC 0.43nH IN+ OUT- 0.65nH 0.11pF 0.11pF 0.43nH 50Ω OUT+ 0.11pF VCC 50Ω IN0.11pF 0.65nH 24kΩ Figure 5. Simplified Input Circuit Schematic Input Termination Requirements The MAX3736 data inputs are SFP MSA compliant. Onchip 100Ω, differential input impedance is provided for optimal termination (Figure 5).
PAGE 10
Chip Information Laser Safety and IEC 825 Using the MAX3736 laser driver alone does not ensure that a transmitter design is compliant with IEC 825. The entire transmitter circuit and component selections must be considered. Customers must determine the level of fault tolerance required by their application.
PAGE 11
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