DS1875 Rev 1 10/08 PON Triplexer and SFP Controller General Description Features The DS1875 controls and monitors all functions for burst- Meets All PON Burst-Timing Requirements for mode transmitters, APD receivers, and video receivers. Burst-Mode Operation It also includes a power-supply controller for APD bias Laser Bias Controlled by APC Loop and generation, and provides all SFF-8472 diagnostic and Temperature Lookup Table (LUT) monitoring functionality. The combined solution of the Laser Modulation Controlled by Temperature LUT DS1875 and the MAX3643 laser driver provides APC loop, modulation current control, and eye safety func- Six Total DACs: Four External, Two Internal tionality. Ten ADC channels monitor V , temperature CC Two 8-Bit DACs, One of Which is Optionally (both internal signals), and eight external monitor inputs Controlled by MON4 Voltage (MON1MON8) that can be used to meet transmitter, Internal 8-Bit DAC Controlled by a Temperature- digital receiver, video receiver, and APD receiver-signal Indexed LUT monitoring requirements. Four total DAC outputs are available. A PWM controller with feedback and compen- PWM Controller sation pins can be used to generate the bias for an APD Boost or Buck Mode or as a step-down converter. Five I/O pins allow addi- Boost Mode: Uses Optional External tional monitoring and configuration. Components, Up to 90V Bias Generation 131kHz, 262kHz, 525kHz, or 1050kHz Selectable- Applications Switching Frequency BPON, GPON, or EPON Optical Triplexers APD Overcurrent Protection Using Optional Fast SFF, SFP, and SFP+ Transceiver Modules Shutdown APD Controller 10 Analog Monitor Channels: Temperature, V , CC Eight Monitors Ordering Information Internal, Factory-Calibrated Temperature Sensor PART TEMP RANGE PIN-PACKAGE RSSI with 29dB Electrical Dynamic DS1875T+ -40C to +95C 38 TQFN-EP* Five I/O Pins for Additional Control and Monitoring Functions, Four of Which are Either DS1875T+T&R -40C to +95C 38 TQFN-EP* Digital I/O or Analog Monitors +Denotes a lead-free/RoHS-compliant package. Comprehensive Fault-Measurement System with T&R = Tape and reel. *EP = Exposed pad. Maskable Laser Shutdown Capability Two-Level Password Access to Protect Pin Configuration Calibration Data TOP VIEW 120 Bytes of Password-1 Protected Memory 128 Bytes of Password-2 Protected Memory in 31 30 29 28 27 26 25 24 23 22 21 20 Main Device Address GND 32 19 MON4 256 Additional Bytes Located at A0h Slave GND 33 18 MON2 Address SW 34 17 MON1 2 I C-Compatible Interface for Calibration and V 35 16 MON8/D3 CC DS1875 Monitoring N.C. 36 15 MON7/D2 2.85V to 3.9V Operating Voltage Range N.C. 37 14 MON6/D1 N.C. 38 13 MON5/D0 *EP -40C to +95C Operating Temperature Range + 38-Pin TQFN (5mm x 7mm) Package 1 2 3 4567 89 10 11 12 TQFN (5mm 7mm 0.8mm) *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. BEN V CC BMD SDA SCL COMP TX-F MOD BIAS N.C. FETG FB M4DAC N.C. GND TX-D V DAC1 CC GND MON3P N.C. MON3N LOSI N.C.PON Triplexer and SFP Controller TABLE OF CONTENTS Absolute Maximum Ratings 5 Recommended Operating Conditions 5 AC Electrical Characteristics .5 Electrical Characteristics (DAC1 and M4DAC) .6 Analog Input Characteristics (BMD, TXP HI, TXP LO, HBIAS) .6 Analog Output Characteristics 6 PWM Characteristics .7 Timing Characteristics (Control Loop and Quick Trip) .7 Analog Voltage Monitoring .8 Digital Thermometer 8 Nonvolatile Memory Characteristics .8 2 I C Timing Specifications 9 Typical Operating Characteristics 10 Pin Description .13 Block Diagram .14 Typical Operating Circuit .15 Detailed Description .16 Bias Control .16 Autodetect Bias Control 16 Open-Loop Bias Control 16 Closed-Loop Bias Control .16 DC Operation 17 Modulation Control .17 BIAS and MOD Output During Power-Up 17 BIAS and MOD Output as a Function of Transmit Disable (TX-D) .18 APC and Quick-Trip Shared Comparator Timing 18 Monitors and Fault Detection .19 Monitors 19 Power-On Analog (POA) 19 Quick-Trip Monitors and Alarms 19 MON3 Quick Trip .19 ADC Monitors and Alarms 19 ADC Timing 20 Right-Shifting ADC Result .21 Transmit Fault (TX-F) Output 21 Safety Shutdown (FETG) Output .22 2 Determining Alarm Causes Using the I C Interface 22 2 DS1875