I (A) CHANNEL 1 TEMP (C) IN1 V (V) OUT1 I (A) OUT1 LTM4676A Dual 13A or Single 26A Module Regulator with Digital Power System Management Fea T Descrip T n Dual, Fast, Analog Loops with Digital Interface for The LTM 4676A is a dual 13A or single 26A step-down Control and Monitoring Module (micromodule) DC/DC regulator with 40ms n Wide Input Voltage Range: 4.5V to 26.5V turn-on time. It features remote configurability and n Output Voltage Range: 0.5V to 5.5V telemetry-monitoring of power management parameters 2 n 0.5% Maximum DC Output Error Over Temperature over PMBus an open standard I C-based digital interface n 2.5% Current Readback Accuracy at 10A Load protocol . The LTM4676A is comprised of fast analog 2 n 400kHz PMBus-Compliant I C Serial Interface control loops, precision mixed-signal circuitry, EEPROM, n Integrated 16-Bit ADC power MOSFETs, inductors and supporting components. n Supports Telemetry Polling Rates Up to 125Hz The LTM4676As 2-wire serial interface allows outputs to n Constant Frequency Current Mode Control be margined, tuned and ramped up and down at program- n Parallel and Current Share Multiple Modules mable slew rates with sequencing delay times. Input and n All 7-Bit Slave Addresses Supported output currents and voltages, output power, temperatures, n Pin-Compatible to Dual 18A LTM4677 uptime and peak values are readable. At start-up, output n 16mm 16mm 5.01mm BGA Package voltages, switching frequency, and channel phase angle assignments can be set by pin-strapping resistors. The Readable Data: n LTpowerPlay GUI and DC1613 USB-to-PMBus converter Input and Output Voltages, Currents, and Temperatures n and demo kits are available. Running Peak Values, Uptime, Faults and Warnings n Onboard EEPROM Fault Log Record with ECC The LTM4676A is pin-compatible and the improved performance version of the LTM4676. Writable Data and Configurable Parameters: n L, LT, LTC, LTM, Linear Technology, the Linear logo, Module and PolyPhase are registered Output Voltage, Voltage Sequencing and Margining trademarks and LTpowerPlay is a trademark of Analog Devices, Inc. All other trademarks are n Digital Soft-Start/Stop Ramp the property of their respective owners. Protected by U.S. Patents including 5408150, 5481178, 5705919, 5929620, 6144194, 6177787, 6580258, 7420359, 8163643. Licensed under U.S. n OV/UV/OT, UVLO, Frequency and Phasing Patent 7000125 and other related patents worldwide. Click to view associated Video Design Idea. a T n System Optimization, Characterization and Data Min- ing in Prototype, Production and Field Environments Using PMBus and LTpowerPlay to Monitor Telemetry and Margin Typical a T V /V During Load Pattern Tests. 10Hz Polling Rate. 12V OUT0 OUT1 IN Dual 13A Module Regulator with Digital Output Voltage Readback, V Margined 7.5% Low Input Current Readback OUT Interface for Control and Monitoring* 1.1 1.9 1.5 2.4 V , OUT0 V IN V V ADJUSTABLE 1.0 1.8 1.0 1.6 IN0 OUT0 5.75V TO 26.5V V UP TO 13A IN1 + 22F V OSNS0 0.9 1.7 0.5 0.8 SV 3 IN 100F LOAD 0 7 RUN 0 0.8 1.6 0 0 ON/OFF CONTROL V OSNS0 RUN 0 3 6 9 12 0 3 6 9 12 1 V , LTM4676A OUT1 TIME (SEC) 4676A TA01b TIME (SEC) 4676A TA01d V ADJUSTABLE OUT1 FAULT INTERRUPTS, GPIO UP TO 13A 0 V OSNS1 Output Current Readback, Varying Load Pattern Power Stage Temperature Readback POWER SEQUENCING GPIO 1 100F 15 15 60 60 LOAD 1 7 PWM CLOCK AND SYNC SGND TIME-BASE 10 10 57 57 SHARE CLK SYNCHRONIZATION SCL 2 I C/SMBus I/F WITH 5 5 54 54 SDA REGISTER WRITE PMBus COMMAND SET WP ALERT GND PROTECTION TO/FROM IPMI OR OTHER 0 0 51 51 4676A TA01a BOARD MANAGEMENT 0 3 6 9 12 0 3 6 9 12 CONTROLLER *FOR COMPLETE CIRCUIT, SEE FIGURE 69 TIME (SEC) 4676A TA01c TIME (SEC) 4676A TA01e 4676afa 1 For more information www.linear.com/LTM4676A V (V) I (A) OUT0 OUT0 CHANNEL 0 TEMP (C) I (A) IN0 ion pplica ions pplica ion uresLTM4676A Table o F c T Ts Features ........................................................... 1 Open-Drain Pins .............................................................57 Applications ...................................................... 1 Phase-Locked Loop and Frequency Synchronization.....58 Typical Application .............................................. 1 RCONFIG Pin-Straps (External Resistor Description........................................................ 1 Configuration Pins) ........................................................59 Absolute Maximum Ratings .................................... 3 Voltage Selection ...........................................................59 2 Order Information ................................................ 3 Connecting the USB to the I C/SMBus/PMBus Pin Configuration ................................................ 3 Controller to the LTM4676A In System ..........................59 Electrical Characteristics ....................................... 4 LTpowerPlay: An Interactive GUI for Digital Power Typical Performance Characteristics ........................ 11 System Management .....................................................63 Pin Functions .................................................... 14 PMBus Communication and Command Processing .......64 Simplified Block Diagram ..................................... 19 Thermal Considerations and Output Current Derating ...65 Decoupling Requirements ..................................... 19 EMI Performance ...........................................................73 Functional Diagram ............................................ 20 Safety Considerations .................................................... 74 Test Circuits ..................................................... 21 Layout Checklist/Example .............................................. 74 Operation......................................................... 22 Typical Applications ............................................ 75 Power Module Introduction ............................................22 Appendix A ....................................................... 81 2 Power Module Configurability and Readback Data ........ 24 Similarity Between PMBus, SMBus and I C Time-Averaged and Peak Readback Data .......................26 2-Wire Interface .............................................................81 Power Module Overview ................................................30 Appendix B ....................................................... 82 EEPROM .........................................................................33 PMBus Serial Digital Interface .......................................82 Serial Interface ...............................................................34 Appendix C: PMBus Command Details ...................... 86 Device Addressing .........................................................35 Addressing and Write Protect ........................................86 Fault Detection and Handling .........................................35 General Configuration Registers ....................................88 Responses to V and I Faults................................36 On/Off/Margin ................................................................89 OUT OUT Responses to Timing Faults ...........................................37 PWM Config ...................................................................91 Responses to SV OV Faults .........................................38 Voltage ...........................................................................93 IN Responses to OT/UT Faults ............................................38 Current ...........................................................................96 Responses to External Faults ........................................38 Temperature ...................................................................99 Fault Logging .................................................................38 Timing .......................................................................... 100 Bus Timeout Protection .................................................39 Fault Response ............................................................. 102 PMBus Command Summary .................................. 40 Fault Sharing ................................................................ 110 PMBus Commands .......................................................40 Scratchpad ................................................................... 112 V to V Step-Down Ratios ....................................... 51 Identification ................................................................ 112 IN OUT Input Capacitors ............................................................. 51 Fault Warning and Status ............................................. 114 Output Capacitors .......................................................... 51 Telemetry ..................................................................... 121 Light Load Current Operation ......................................... 51 NVM (EEPROM) Memory Commands .......................... 125 Switching Frequency and Phase ....................................52 Package Description ......................................... 132 Minimum On-Time Considerations .................................54 Package Photograph ......................................... 133 Variable Delay Time, Soft-Start and Output Voltage Package Description ......................................... 134 Ramping .........................................................................54 Revision History .............................................. 135 Digital Servo Mode ........................................................55 Typical Application ........................................... 136 Soft Off (Sequenced Off) ...............................................56 Design Resources ............................................ 136 Undervoltage Lockout ....................................................56 Related Parts .................................................. 136 Fault Detection and Handling .........................................57 4676afa 2 For more information www.linear.com/LTM4676A en on