DS1874 19-4691 Rev 0 6/09 SFP+ Controller with Digital LDD Interface General Description Features The DS1874 controls and monitors all functions for SFF, Meets All SFF-8472 Control and Monitoring SFP, and SFP+ modules including all SFF-8472 func- Requirements tionality. The combination of the DS1874 with the Laser Bias Controlled by APC Loop and MAX3798/MAX3799 laser driver/limiting amplifier pro- Temperature LUT to Compensate for Tracking vides APC loop, modulation current control, and eye Error safety functionality. The DS1874 continuously monitors Laser Modulation Controlled by Temperature LUT for high output current, high bias current, and low and high transmit power to ensure that laser shutdown for Six Analog Monitor Channels: Temperature, V , CC eye safety requirements are met without adding external MON1MON4 components. Six ADC channels monitor V , tempera- MON1MON4 Support Internal and External CC ture, and four external monitor inputs (MON1MON4) Calibration that can be used to meet all monitoring requirements. Scalable Dynamic Range MON3 is differential with support for common mode to Internal Direct-to-Digital Temperature Sensor V . Two digital-to-analog (DAC) outputs with tempera- Alarm and Warning Flags for All Monitored CC ture-indexed lookup tables (LUTs) are available for addi- Channels tional monitoring and control functionality. Two 9-Bit Delta-Sigma Outputs with 36 Entry Temperature LUTs Applications Digital I/O Pins: Five Inputs, Five Outputs SFF, SFP, and SFP+ Transceiver Modules Comprehensive Fault-Measurement System with Maskable Laser Shutdown Capability Pin Configuration Flexible, Two-Level Password Scheme Provides Three Levels of Security TOP VIEW 256 Additional Bytes Located at A0h Slave Address 21 20 19 18 17 16 15 2 I C-Compatible Interface N.C. 22 14 MON1 3-Wire Master to Communicate with the MAX3798/ 13 MON3N MAX3799 Laser Driver/Limiting Amplifier V 23 CC +2.85V to +3.9V Operating Voltage Range 24 12 MON3P CSELOUT MON4 -40C to +95C Operating Temperature Range 25 11 SCLOUT DS1874 28-Pin TQFN (5mm x 5mm) Package 26 10 SDAOUT TXDOUT LOSOUT 27 9 RSEL *EP + Ordering Information OUT1 28 8 GND PART TEMP RANGE PIN-PACKAGE 12 3 45 6 7 DS1874T+ -40C to +95C 28 TQFN-EP* DS1874T+T&R -40C to +95C 28 TQFN-EP* +Denotes a lead(Pb)-free/RoHS-compliant package. THIN QFN (5mm 5mm 0.8mm) T&R = Tape and reel. *EP = Exposed pad. *EXPOSED PAD. 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. RSELOUT GND SCL DAC2 SDA DAC1 TXF REFIN LOS GND IN1 MON2 V TXD CCSFP+ Controller with Digital LDD Interface TABLE OF CONTENTS Absolute Maximum Ratings 5 Recommended Operating Conditions 5 DC Electrical Characteristics .5 DAC1, DAC2 Electrical Characteristics .6 Analog Quick-Trip Characteristics .6 Analog Voltage Monitoring Characteristics 6 Digital Thermometer Characteristics .7 AC Electrical Characteristics .7 Timing Characteristics (Control Loop and Quick Trip) .7 3-Wire Digital Interface Specification .7 2 I C AC Electrical Characteristics 8 Nonvolatile Memory Characteristics .8 Typical Operating Characteristics .9 Pin Description .10 Block Diagram .11 Typical Operating Circuit .12 Detailed Description .12 MAX3798/MAX3799 DAC Control 12 BIAS Register/APC Control .12 MODULATION Control 13 BIAS and MODULATION Control During Power-Up 14 BIAS and MODULATION Registers as a Function of Transmit Disable (TXD) 15 APC and Quick-Trip Timing .15 Monitors and Fault Detection .16 Monitors 16 Five Quick-Trip Monitors and Alarms 16 Six ADC Monitors and Alarms .16 ADC Timing 16 Right-Shifting ADC Result .16 Enhanced RSSI Monitoring (Dual-Range Functionality) 17 Low-Voltage Operation 19 Power-On Analog (POA) 19 Delta-Sigma Outputs (DAC1 and DAC2) 19 Digital I/O Pins .21 LOS, LOSOUT 21 IN1, RSEL, OUT1, RSELOUT 21 TXF, TXD, TXDOUT 21 2 DS1874