DS1878 19-5537 Rev 1 8/11 SFP+ Controller with Digital LDD Interface General Description Features The DS1878 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 DS1878 with Maxim Laser Bias Controlled by APC Loop and laser driver/limiting amplifier solutions supports VCSEL, Temperature LUT to Compensate for Tracking DFB, and EML-based solutions. The device provides Error APC loop, modulation current control, and eye safety Laser Modulation Controlled by Temperature LUT functionality. It continuously monitors for high output current, high bias current, and low and high transmit Six Analog Monitor Channels: Temperature, V , CC power to ensure that laser shutdown for eye safety MON1MON4 requirements are met without adding external compo- MON1MON4 Support Internal and External nents. Six ADC channels monitor V , temperature, Calibration CC and four external monitor inputs (MON1MON4) that Scalable Dynamic Range can be used to meet all monitoring requirements. Internal Direct-to-Digital Temperature Sensor MON3 is differential with support for common mode to Alarm and Warning Flags for All Monitored V . Two digital-to-analog (DAC) outputs with tempera- Channels CC ture-indexed lookup tables (LUTs) are available for Two 9-Bit Delta-Sigma Outputs with 36 Entry additional control functionality. Temperature LUTs Digital I/O Pins: Five Inputs, Four Outputs Applications Comprehensive Fault-Measurement System with SFF, SFP, and SFP+ Transceiver Modules Maskable Laser Shutdown Capability Flexible, Two-Level Password Scheme Provides Ordering Information Three Levels of Security PART TEMP RANGE PIN-PACKAGE 256 Additional Bytes Located at A0h Slave Address DS1878T+ -40C to +95C 28 TQFN-EP* 2 I C-Compatible Interface DS1878T+T&R -40C to +95C 28 TQFN-EP* 3-Wire Master to Communicate with a Maxim +Denotes a lead(Pb)-free/RoHS-compliant package. T&R = Tape and reel. Laser Driver/Limiting Amplifier *EP = Exposed pad. +2.85V to +5.5V Operating Voltage Range -40C to +95C Operating Temperature Range 28-Pin TQFN (5mm x 5mm x 0.75mm) Package 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.SFP+ 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 Input Characteristics (MON2, TXP HI, TXP LO, HBIAS, LOS) 6 Analog Voltage Monitoring Characteristics 6 Digital Thermometer Characteristics .7 AC Electrical Characteristics .7 Control Loop and Quick-Trip Timing Characteristics .7 3-Wire Digital Interface Specification .7 2 I C AC Electrical Characteristics 8 Nonvolatile Memory Characteristics .8 Typical Operating Characteristics .9 Pin Configuration .10 Pin Description .10 Block Diagram .11 Typical Operating Circuit .12 Detailed Description .12 3-Wire DAC Control .12 BIAS Register/APC Control, 3-Wire Mode 13 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 .17 Enhanced RSSI Monitoring (Dual-Range Functionality) 18 Low-Voltage Operation 19 Power-On Analog (POA) 20 Delta-Sigma Outputs (DAC1 and DAC2) 20 Digital I/O Pins .21 LOS, LOSOUT 21 IN1, RSEL, RSELOUT 22 TXD, TXDOUT 22 2 DS1878