LTC2978 Octal Digital Power Supply Manager with EEPROM NOT RECOMMENDED FOR NEW DESIGNS Please See LTC2978A for Drop-In Replacement Fea Tures Descrip T 2 n I C/SMBus Serial Interface The LTC 2978 is an octal, digital power-supply monitor, n PMBus Compliant Command Set supervisor, sequencer, and margin controller. Eight output n Configuration EEPROM with CRC channels can be managed per user defined configura- n Black Box Fault Logging to Internal EEPROM tion settings. Supervisory functions include fault OV/UV n Differential Input, 16-Bit ADC with Less Than threshold limits for eight output channels and one input 0.25% of Total Unadjusted Error channel. Programmable fault dependencies and responses n Eight Voltage Servos Precisely Adjust Output allow the power supplies to be disabled with optional retry Voltages Using Eight 10-Bit DACs with Soft-Connect after a fault has been detected. Serial bus telemetry allows n Monitors Eight Output Voltages and One Input eight output voltages, one input voltage, die temperature Voltage and Internal Die Temperature and fault status to be monitored. In addition, odd num- n 8-Channel Sequencer bered channels can be configured to measure the voltage n Programmable Watchdog Timer across a current sense resistor. Power supply sequencing, n Eight UV/OV V and One V Supervisor precision point-of-load voltage adjustment and margining OUT IN n Supports Multi-Channel Fault Management are supported with PMBus commands. A programmable n Operates Autonomously without Additional Software watchdog timer monitors microprocessor activity for a n LTC2978 Can Be Powered from 3.3V or 4.5V to 15V stalled condition and resets the microprocessor if neces- n Available in 64-pin 9mm 9mm QFN Package sary. The 1-wire synchronization bus supports power supply sequencing across multiple LTC digital power devices. User programmable parameters can be stored a Tions in EEPROM. Faults and telemetry data can be logged to n Computers EEPROM for diagnostic analysis. n Network Servers n L, LT, LTC, LTM, PolyPhase, Linear Technology and the Linear logo are registered trademarks Industrial Test and Measurement and LTpowerPlay ia a trademark of Linear Technology Corporation. All other trademarks are the n High Reliability Systems property of their respective owners. Protected by U.S. Patents including 7382303 and 7420359. n Medical Imaging n Video Typical a T Typical ADC Total Unadjusted Octal Power Supply Controller with PMBus Interface Error vs Temperature 0.035 ADC V = 1.8V 4.5V < V < 15V V IN IN IBUS 0.030 V V V PWR IN SNS OUT 3.3V** V V DIGITALLY DD33 DACP0 0.025 MANAGED V SENSEP0 R30 TO INTERMEDIATE V POWER IN EN BUS CONVERTER ENABLE R20 0.020 SUPPLY LTC2978* V SDA LOAD FB 0.015 SCL V PMBus DACM0 R10 INTERFACE ALERTB V SGND SENSEM0 0.010 CONTROL0 V RUN/SS OUT EN0 GND 0.005 WRITE-PROTECT TO P RESETB INPUT WP PWRGD 0 WDI/RESETB WATCHDOG 50 35 20 5 10 25 40 55 70 85 100 TIMER INTERRUPT FAULTB00 ASEL0 TO/FROM OTHER TEMPERATURE (C) LTC2978s SHARE CLK ASEL1 *SOME DETAILS OMITTED FOR CLARITY 2978 TA01b ONLY ONE OF EIGHT CHANNELS SHOWN GND 2978 TA01a **LTC2978 MAY BE POWERED FROM EITHER AN EXTERNAL 3.3V SUPPLY OR THE INTERMEDIATE BUS 2978fd 1 For more information www.linear.com/LTC2978 ERROR (%) ion pplica pplica ionLTC2978 Table o F c T Ts Features ..................................................... 1 Input Voltage Related Commands ...........................33 Applications ................................................ 1 VIN ON, VIN OFF, VIN OV FAULT LIMIT, VIN Typical Application ........................................ 1 OV WARN LIMIT, VIN UV WARN LIMIT and Description.................................................. 1 VIN UV FAULT LIMIT .......................................33 Absolute Maximum Ratings .............................. 4 Temperature Related Commands ............................34 Order Information .......................................... 4 OT FAULT LIMIT, OT WARN LIMIT, UT WARN Pin Configuration .......................................... 4 LIMIT and UT FAULT LIMIT ...............................34 Electrical Characteristics ................................. 5 Timer Limits ...........................................................34 PMBus Timing Diagram ................................... 9 TON DELAY, TON RISE, TON MAX FAULT Typical Performance Characteristics .................. 10 LIMIT and TOFF DELAY......................................34 Pin Functions .............................................. 14 Fault Response for Voltages Measured by the High Block Diagram ............................................. 16 Speed Supervisor ...................................................35 Operation................................................... 17 VOUT OV FAULT RESPONSE and VOUT UV Operation Overview ................................................ 17 FAULT RESPONSE .............................................35 EEPROM ............................................................. 17 Fault Response for Values Measured by the ADC ...36 Reset ...................................................................... 18 OT FAULT RESPONSE, UT FAULT RESPONSE, Write-Protect Pin .................................................... 18 VIN OV FAULT RESPONSE and VIN UV FAULT Other Operations .................................................... 18 RESPONSE .........................................................36 Clock Sharing ..................................................... 18 Timed Fault Response ............................................36 PMBus Serial Digital Interface ................................ 19 TON MAX FAULT RESPONSE ..........................36 PMBus ................................................................ 19 Status Commands ..................................................37 Device Address ...................................................22 STATUS BYTE: ...................................................37 Processing Commands .......................................23 STATUS WORD: .................................................38 PMBus Command Summary ............................ 24 STATUS VOUT ...................................................38 Summary Table ................................................... 24 STATUS INPUT ..................................................39 Data Formats ......................................................28 STATUS TEMPERATURE ....................................39 PMBus Command Description .......................... 29 STATUS CML .....................................................40 Operation, Mode and EEPROM Commands ............29 STATUS MFR SPECIFIC ....................................40 PAGE ..................................................................29 ADC Monitoring Commands ................................... 41 OPERATION ........................................................30 READ VIN .......................................................... 41 ON OFF CONFIG ................................................31 READ VOUT ....................................................... 41 CLEAR FAULTS..................................................31 READ TEMPERATURE 1 .................................. 41 WRITE PROTECT ...............................................32 PMBUS REVISION ............................................. 41 STORE USER ALL and RESTORE USER ALL .32 Manufacturer Specific Commands ..........................42 CAPABILITY ........................................................32 MFR CONFIG LTC2978 .....................................42 VOUT MODE ......................................................33 MFR CONFIG ALL LTC2978 ............................43 Output Voltage Related Commands ........................33 MFR FAULTz0 PROPAGATE, MFR FAULTz1 VOUT COMMAND, VOUT MAX, VOUT MARGIN PROPAGATE .......................................................44 HIGH, VOUT MARGIN LOW, VOUT OV FAULT MFR PWRGD EN ..............................................45 LIMIT, VOUT OV WARN LIMIT, VOUT UV MFR FAULTB00 RESPONSE, MFR FAULTB01 WARN LIMIT, VOUT UV FAULT LIMIT, POWER RESPONSE, MFR FAULTB10 RESPONSE and GOOD ON and POWER GOOD OFF ..................33 MFR FAULTB11 RESPONSE ..............................46 2978fd 2 For more information www.linear.com/LTC2978 en on