LTC2975 4-Channel PMBus Power System Manager Featuring Accurate Input Current and Energy Measurement FEATURES DESCRIPTION n Sequence, Trim, Margin and Supervise Four Power The LTC 2975 is a 4-channel Power System Manager used to sequence, trim (servo), margin, supervise, manage Supplies n faults, provide telemetry and create fault logs. PMBus Manage Faults, Monitor Telemetry and Create Fault Logs n commands support power supply sequencing, precision PMBus Compliant Command Set n point-of-load voltage adjustment and margining. DACs Supported by LTpowerPlay GUI use a proprietary soft-connect algorithm to minimize n Margin or Trim Supplies to Within 0.25% of Target supply disturbances. Supervisory functions include over n Monitor Input Current (1%) and Accumulate Energy and under current, voltage and temperature threshold n Fast OV/UV and OC Supervisors Per Channel limits for four power supply output channels as well as n Coordinate Sequencing and Fault Management over and under voltage threshold limits for a single power Across Multiple ADI PSM Devices supply input channel. Programmable fault responses n Automatic Fault Logging to Internal EEPROM can disable the power supplies with optional retry after a n Operate Autonomously Without Additional Software fault is detected. Faults that disable a power supply can n External Temperature and Input Voltage Supervisors automatically trigger black box EEPROM storage of fault n Accurate Monitoring of Four Output Voltages, Four status and associated telemetry. An internal 16-bit ADC Output Currents, Four External Temperatures, Input monitors four output voltages, four output currents, four Voltage and Current, and Internal Die Temperature external temperatures, input voltage and current, and die n Can Be Powered from 3.3V, or 4.5V to 15V temperature. Input power, energy, and output power is n Pin-Compatible to the LTC2974 also calculated. A programmable watchdog timer mon- n Available in 64-Lead 9mm 9mm QFN Package and in itors microprocessor activity for a stalled condition and 63-Lead 6.25mm 7.5mm BGA Package resets the microprocessor if necessary. A single wire bus synchronizes power supplies across multiple ADI APPLICATIONS Power System Management (PSM) devices. Configuration n Computers and Network Servers EEPROM with ECC supports autonomous operation without n Industrial Test and Measurement additional software. n High Reliability Systems All registered trademarks and trademarks are the property of their respective owners. Protected by U.S. patents, including 7382303, 7420359 and 8648623. n Video and Medical Imaging TYPICAL APPLICATION 4-Channel PMBus Power System Manager with Input Energy Metering Power Measurement Error 2 IBC 4.5V V 15V IBUS Mfr ein cong iin range = Medium DC IN OUT IN V = 50mV IIN SNS V = 12V I I VIN SNS IN SNSP IN SNSM V I IN SENSEP 1 V V OUT IN SNS DC/DC CONVERTER *LTC2975 MAY ALSO BE V RUN V * I FB PWR SENSEM POWERED DIRECTLY FROM 0 V * V AN EXTERNAL 3.3V SUPPLY DD33 SENSEP LTC2975 LOAD R20 V SENSEM SDA PMBus 1 V DAC SCL INTERFACE R30 R10 ALERTB CONTROL V 6 TYPICAL PARTS OUT EN FAULT 2 T SENSE PWRGD MMBT3906 GND 50 25 0 25 100 50 75 NOTE: SOME DETAILS OMITTED FOR CLARITY TEMPERATURE (C) 2975 TA01 ONLY ONE OF FOUR CHANNELS SHOWN 2975 TA01b Rev. 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Information .............................................................. 5 Input Current and Energy ................................................................ 49 Electrical Characteristics ..................................................... 5 Energy Measurement and Reporting ........................................ 49 PMBus Timing Diagram ......................................................10 MFR EIN .................................................................................. 49 Typical Performance Characteristics ......................................11 MFR EIN CONFIG .................................................................... 50 Pin Functions ..................................................................15 MFR IIN CAL GAIN ................................................................. 50 Block Diagram .................................................................17 MFR IIN CAL GAIN TC ........................................................... 51 Operation.......................................................................18 MFR CLEAR ENERGY .............................................................. 51 LTC2975 Operation Overview ......................................................... 18 Output Voltage Commands and Limits ........................................... 51 EEPROM .................................................................................... 19 VOUT MODE ............................................................................. 52 AUXFAULTB .................................................................................... 19 VOUT COMMAND, VOUT MAX, VOUT MARGIN HIGH, VOUT RESETB ........................................................................................... 20 MARGIN LOW, VOUT OV FAULT LIMIT, PMBus Serial Digital Interface ........................................................ 20 VOUT OV WARN LIMIT, VOUT UV WARN LIMIT, VOUT UV PMBus ....................................................................................... 20 FAULT LIMIT, POWER GOOD ON and Device Address .......................................................................... 20 POWER GOOD OFF .................................................................. 52 Processing Commands ............................................................. 21 MFR VOUT DISCHARGE THRESHOLD ................................... 52 PMBUS Command Summary ................................................24 MFR DAC .................................................................................. 52 PMBus Command Description ..............................................30 Output Current Commands and Limits ........................................... 53 Addressing and Write Protect ......................................................... 30 IOUT CAL GAIN ....................................................................... 53 PAGE .......................................................................................... 30 IOUT OC FAULT LIMIT, IOUT OC WARN LIMIT and IOUT WRITE PROTECT ...................................................................... 31 UC FAULT LIMIT ...................................................................... 53 Write Protect Pin ....................................................................... 31 MFR IOUT CAL GAIN TC ....................................................... 53 MFR PAGE FF MASK .............................................................. 31 External Temperature Commands and Limits ................................ 54 MFR I2C BASE ADDRESS ...................................................... 32 OT FAULT LIMIT, OT WARN LIMIT, UT WARN LIMIT and MFR COMMAND PLUS ........................................................... 32 UT FAULT LIMIT ...................................................................... 55 MFR DATA PLUS0 and MFR DATA PLUS1 ........................... 32 MFR TEMP 1 GAIN and MFR TEMP 1 OFFSET ..................... 55 MFR STATUS PLUS0, and MFR STATUS PLUS1 .................. 32 MFR T SELF HEAT, MFR IOUT CAL GAIN TAU INV and Reading Fault Log Using Command Plus and Mfr data plus0 33 MFR IOUT CAL GAIN THETA ................................................. 55 Reading Energy Using MFR COMMAND PLUS and MFR Sequencing Timing Limits and Clock Sharing ................................ 57 DATA PLUS0 ............................................................................. 34 TON DELAY, TON RISE, TON MAX FAULT LIMIT and TOFF Peek Operation Using Mfr data plus0 ..................................... 34 DELAY ........................................................................................ 57 Enabling and Disabling Poke Operations .................................. 34 Watchdog Timer and Power Good .................................................. 58 Poke Operation Using Mfr data plus0 ..................................... 34 MFR PWRGD EN ..................................................................... 58 Command Plus Operations Using Mfr data plus1 ................... 35 MFR RESTART DELAY ............................................................ 58 On/Off Control, Margining and Configuration ................................ 35 Clock Sharing ............................................................................ 58 OPERATION ............................................................................... 35 MFR POWERGOOD ASSERTION DELAY ............................... 59 ON OFF CONFIG ....................................................................... 36 Watchdog Operation.................................................................. 59 MFR CONFIG LTC2975 ............................................................ 37 MFR WATCHDOG T FIRST and MFR WATCHDOG T ............. 59 Cascade Sequence ON with Time-Based Sequence OFF .......... 38 Fault Responses .............................................................................. 60 MFR CONFIG2 LTC2975 .......................................................... 39 Clearing Latched Faults ............................................................. 60 MFR CONFIG3 LTC2975 .......................................................... 40 VOUT OV FAULT RESPONSE and VOUT UV FAULT Tracking Supplies On and Off .................................................... 41 RESPONSE ................................................................................ 60 Tracking Implementation ........................................................... 44 IOUT OC FAULT RESPONSE and IOUT UC FAULT RESPONSE MFR CONFIG ALL LTC2975 ................................................... 44 ................................................................................................... 61 Programming User EEPROM Space ............................................... 46 OT FAULT RESPONSE, UT FAULT RESPONSE, VIN OV STORE USER ALL and RESTORE USER ALL ....................... 46 FAULT RESPONSE and VIN UV FAULT RESPONSE ............... 62 Bulk Programming the User EEPROM Space ............................ 46 TON MAX FAULT RESPONSE................................................. 63 MFR EE UNLOCK ..................................................................... 47 MFR RETRY DELAY ................................................................. 63 MFR EE ERASE ....................................................................... 47 MFR RETRY COUNT ................................................................ 63 MFR EE DATA .......................................................................... 47 Shared External Faults .................................................................... 64 MFR FAULTB0 PROPAGATE and MFR FAULTB1 PROPAGATE .................................................................................................. 64 Rev. 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