48 V Hot Swap Controller and Digital Power Monitor with PMBus Interface Data Sheet ADM1075 FEATURES PRODUCT HIGHLIGHTS Constant power foldback for FET SOA protection 1. Constant Power Foldback. Precision (<1.0%) current and voltage measurement Maximum FET power set by a PLIM resistor divider. This Controls inrush and faults for negative supply voltages eases complexity when designing to maintain FET SOA. Suitable for wide input range due to internal shunt regulator 2. Adjustable Current Limit. 25 mV/50 mV full-scale sense voltage The current limit is adjustable via the ISET pin allowing for Fine tune current limit to allow use of standard sense resistor the use of a standard value sense resistor. Soft start inrush current limit profiling 3. 12-Bit ADC. 1% accurate UVH and OV pins, 1.5% accurate UVL pin Accurate voltage, current, and power measurements. Also 2 PMBus/I C interface for control, telemetry, and fault enables calculation of energy consumption over time. recording 2 4. PMBus/I C Interface. 28-lead LFCSP and TSSOP PMBus fast mode compliant interface used to read back 40C to 105C junction temperature (T ) operating range J status and data registers and set warning and fault limits. 5. Fault Recording. APPLICATIONS Latched status registers provide useful debugging infor- Telecommunication and data communication equipment mation to help trace faults in high reliability systems. Central office switching 6. Built-In Soft Start. 48 V distributed power systems Soft start capacitor controls inrush current profile with Negative power supply control di/dt control. High availability servers FUNCTIONAL BLOCK DIAGRAM 48V RTN (0V) 12V R DROP SPLYGD SHDN RESTART 5V VIN 3.3V LATCH VCC AND POWER 2.8V VEE REFERENCE GPO1/ALERT1/CONV ACCUMULATOR DC-TO-DC GENERATOR ...etc. GPO2/ALERT2 DIGITAL C CONVERTER UVH SDAO LOAD GND POWER AND UNDERVOLTAGE SDAI MULTIPLIER PMBUS UVL AND SCL OVERVOLTAGE OV DETECTOR 12-BIT ADC ADR ADC AUX ADC V PWRGD FET POWER FOLDBACK DRAIN CONTROL PLIM VCAP SDA ISO FAULT TIMER ADuM1250 VEE SCL ISO ISET N-FET GATE GATE CONTROL SENSE+ CURRENT LIMIT R SENSE SENSE VEE G TIMER SS VEE 48V Figure 1. Rev. D Document Feedback Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. rights of third parties that may result from its use. Specifications subject to change without notice. No Tel: 781.329.4700 20112018 Analog Devices, Inc. All rights reserved. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Technical Support www.analog.com Trademarks and registered trademarks are the property of their respective owners. 09312-001ADM1075 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Group Commands ..................................................................... 30 Applications ....................................................................................... 1 Hot Swap Control Commands ................................................. 31 Product Highlights ........................................................................... 1 ADM1075 Information Commands ........................................ 31 Functional Block Diagram .............................................................. 1 Status Commands ...................................................................... 31 Revision History ............................................................................... 3 GPO and Alert Pin Setup Commands..................................... 32 General Description ......................................................................... 4 Power Monitor Commands ...................................................... 32 Specifications ..................................................................................... 5 Warning Limit Setup Commands ............................................ 33 Serial Bus Timing ......................................................................... 9 PMBus Direct Format Conversion .......................................... 34 Absolute Maximum Ratings .......................................................... 10 Voltage and Current Conversion Using LSB Values .............. 35 Thermal Resistance .................................................................... 10 ADM1075 Alert Pin Behavior ...................................................... 36 ESD Caution ................................................................................ 10 Faults and Warnings .................................................................. 36 Pin Configuration and Function Description ............................ 11 Generating an Alert ................................................................... 36 Typical Performance Characteristics ........................................... 13 Handling/Clearing an Alert ...................................................... 36 Theory of Operation ...................................................................... 20 SMBus Alert Response Address ............................................... 37 Powering the ADM1075 ............................................................ 20 Example Use of SMBus Alert Response Address ................... 37 Current Sense Inputs .................................................................. 21 Digital Comparator Mode ......................................................... 37 Current Limit Reference ............................................................ 21 PMBus Command Reference........................................................ 38 Setting the Current Limit (ISET).............................................. 22 Register Details ............................................................................... 39 Soft Start ...................................................................................... 22 Operation Command Register ................................................. 39 Constant Power Foldback (PLIM) ........................................... 22 Clear Faults Register .................................................................. 39 TIMER ......................................................................................... 23 PMBus Capability Register ....................................................... 39 Setting a Linear Output Voltage Ramp at Power-Up ............. 24 IOUT OC Warn Limit Register ................................................ 39 Hot Swap Fault Retry ................................................................. 25 VIN OV Warn Limit Register ................................................... 39 Fast Response to Severe Overcurrent ...................................... 25 VIN UV Warn Limit Register ................................................... 39 UV and OV ................................................................................. 25 PIN OP Warn Limit Register .................................................... 40 PWRGD Status Byte Register .................................................................... 40 ....................................................................................... 25 Status Word Register .................................................................. 40 DRAIN ......................................................................................... 26 IOUT Status Register ................................................................. 41 SPLYGD ....................................................................................... 26 Input Status Register .................................................................. 41 LATCH ......................................................................................... 26 Manufacturing Specific Status Register ................................... 42 SHDN ........................................................................................... 26 Read EIN Register ...................................................................... 43 RESTART ..................................................................................... 26 Read VIN Register...................................................................... 43 FET Health .................................................................................. 26 Read IOUT Register ................................................................... 43 Power Monitor ............................................................................ 26 Read PIN Register ...................................................................... 43 Isolation ....................................................................................... 27 PMBus Revision Register .......................................................... 43 PMBus Interface ............................................................................. 28 Manufacturing ID Register ....................................................... 44 Device Addressing ...................................................................... 28 Manufacturing Model Register ................................................ 44 SMBus Protocol Usage ............................................................... 28 Manufacturing Revision Register ............................................. 44 Packet Error Checking ............................................................... 28 Peak IOUT Register ................................................................... 44 2 Partial Transactions on I C Bus ................................................ 28 Peak VIN Register ...................................................................... 45 SMBus Message Formats ........................................................... 29 Rev. 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