MAX3646 19-3161 Rev 2 6/11 155Mbps to 622Mbps SFF/SFP Laser Driver with Extinction Ratio Control General Description Features The MAX3646 is a +3.3V laser driver designed for mul- Single +3.3V Power Supply tirate transceiver modules with data rates from 47mA Power-Supply Current 155Mbps to 622Mbps. Lasers can be DC-coupled to the MAX3646 for reduced component count and ease 85mA Modulation Current of multirate operation. 100mA Bias Current Laser extinction ratio control (ERC) combines the features of automatic power control (APC), modulation compensa- Automatic Power Control (APC) tion, and built-in thermal compensation. The APC loop Modulation Compensation maintains constant average optical power. Modulation compensation increases the modulation current in pro- On-Chip Temperature Compensation portion to the bias current. These control loops, com- Self-Biased Inputs for AC-Coupling bined with thermal compensation, maintain a constant optical extinction ratio over temperature and lifetime. Ground-Referenced Current Monitors The MAX3646 accepts differential data input signals. Laser Shutdown and Alarm Outputs The wide 5mA to 60mA (up to 85mA AC-coupled) mod- Enable Control and Laser Safety Feature ulation current range and up to 100mA bias current range, make the MAX3646 ideal for driving FP/DFB lasers in fiber optic modules. External resistors set the Ordering Information required laser current levels. The MAX3646 provides transmit disable control (TX DISABLE), single-point PART TEMP RANGE PIN-PACKAGE fault tolerance, bias-current monitoring, and photocur- MAX3646ETG -40C to +85C 24 Thin QFN-EP* rent monitoring. The device also offers a latched failure MAX3646ETG-T -40C to +85C 24 Thin QFN-EP* output (TX FAULT) to indicate faults, such as when the MAX3646ETG+ -40C to +85C 24 Thin QFN-EP* APC loop is no longer able to maintain the average optical power at the required level. The MAX3646 is MAX3646ETG+T -40C to +85C 24 Thin QFN-EP* compliant with the SFF-8472 transmitter diagnostic and +Denotes a lead-free/RoHS-compliant package. SFP MSA timing requirements. *EP = Exposed pad. T = Tape and reel. The MAX3646 is offered in a 4mm x 4mm, 24-pin thin QFN package and operates over the extended -40C to +85C temperature range. Pin Configuration Applications TOP VIEW Multirate OC-3 to OC-12 FEC Transceivers 125Mbps Ethernet SFP, GBIC, and 1 x 9 24 23 22 21 20 19 Transceivers 1 MODTCOMP 18 MD V 2 17 V CC CC IN+ 3 16 OUT+ MAX3646 4 OUT- IN- 15 V 5 V CC 14 CC Typical Application Circuit appears at end of data sheet. *EP TX DISABLE 6 13 BIAS 7 8 9 10 11 12 *THE EXPOSED PADDLE MUST BE SOLDERED TO SUPPLY GROUND ON THE CIRCUIT BOARD. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com. EVALUATION KIT AVAILABLE PC MON TH TEMP BC MON MODBCOMP SHUTDOWN MODSET GND APCSET TX FAULT APCFILT2 GND APCFILT1155Mbps to 622Mbps SFF/SFP Laser Driver with Extinction Ratio Control ABSOLUTE MAXIMUM RATINGS Supply Voltage V ...............................................-0.5V to +6.0V Operating Junction Temperature Range...........-55C to +150C CC IN+, IN-, TX DISABLE, TX FAULT, SHUTDOWN, Lead Temperature (soldering, 10s) .................................+300C BC MON, PC MON, APCFILT1, APCFILT2, Soldering Temperature (reflow) MD, TH TEMP, MODTCOMP, MODBCOMP, Lead (Pb)-free packages..............................................+260C MODSET, and APCSET Voltage.............-0.5V to (V + 0.5V) Packages containing lead (Pb).....................................+240C CC OUT+, OUT-, BIAS Current.............................-20mA to +150mA Storage Temperature Range .............................-55C to +150C Continuous Power Dissipation (T = +70C) A 24-Pin TQFN (derate 27.8mW/C above +70C) .......2222mW 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. ELECTRICAL CHARACTERISTICS (V = +2.97V to +3.63V, T = -40C to +85C. Typical values are at V = +3.3V, I = 60mA, I = 60mA, T = +25C, unless CC A CC BIAS MOD A otherwise noted.) (Notes 1, 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS POWER SUPPLY Supply Current I (Note 3) 47 60 mA CC Power-Supply Noise Rejection PSNR f 1MHz, 100mA (Note 4) 33 dB P-P I/O SPECIFICATIONS Differential Input Swing V DC-coupled, Figure 1 0.2 2.4 V ID P-P V - CC Common-Mode Input V 1.7 V CM V / 4 ID LASER BIAS Bias-Current-Setting Range 1 100 mA Bias Off Current TX DISABLE = high 0.1 mA Bias-Current Monitor Ratio I / I 62 76 90 mA/mA BIAS BC MON LASER MODULATION Modulation Current-Setting I (Note 5) 5 85 mA MOD Range 20% to 80% Output Edge Speed 5mA I 85mA 100 200 ps MOD (Notes 6, 7) Output Overshoot/Undershoot (Note 7) 6% Random Jitter (Notes 6, 7) 1.1 2.5 ps RMS 622Mbps, 5mA I 85mA 24 46 MOD Deterministic Jitter (Notes 6, 8) ps P-P 155Mbps, 5mA I 85mA 45 100 MOD 5mA I 10mA 175 600 Modulation-Current Temperature MOD (Note 6) ppm/C Stability 10mA < I 85mA 125 480 MOD 5mA I 10mA 20 15 load, MOD Modulation-Current-Setting Error % T = +25C A 10mA < I 85mA 15 MOD Modulation Off Current TX DISABLE = high 0.1 mA 2 MAX3646