CHANNEL 1 TEMP (C) I (A) IN1 V (V) OUT1 I (A) OUT1 LTM4686/LTM4686-1 Ultrathin Dual 10A or Single 20A Module Regulator with Digital Power System Management FEATURES DESCRIPTION n Dual, Fast, Analog Loops with Digital Interface for The LTM 4686 is a dual 10A (12A Peak) or single 20A Control and Monitoring (24A Peak) step-down Module (micromodule) DC/ n DC regulator with 39ms turn-on time. It features remote Wide Input Voltage Range: 4.5V to 17V Standalone, 2.375V to 17V with Aux 5V Bias (LTM4686-1) configurability and telemetry-monitoring of power man- n Output Voltage Range: 0.5V to 3.6V agement parameters over PMBusan open standard 2 n I C-based digital interface protocol . The LTM4686 is 0.5% Maximum DC Output Error Over Temperature n comprised of fast analog control loops, precision mixed- 10A DC Typical, 12A Peak Output Current, per Channel n signal circuitry, EEPROM, power MOSFETs, inductors and 5% Current Readback Accuracy at 10A Load 2 n supporting components. The LTM4686 product video is 400kHz PMBus-Compliant I C Serial Interface n available on the website. Click here . Integrated 16-Bit ADC n Supports Telemetry Polling Rates Up to 125Hz The LTM4686s 2-wire serial interface enables voltage n Constant Frequency Current Mode Control margining and sequencing, and telemetry readback of n Parallel and Current Share Multiple Modules currents, voltages, power, temperature, uptime and peak n All 7-Bit Slave Addresses Supported values. Pin-strap resistors configure start-up settings. The n Drop-In Pin-Compatible to Dual 9A LTM4675 and LTpowerPlay GUI, DC1613 USB-to-PMBus converter, Dual 13A LTM4676A and Dual 18A LTM4677 DC2086 programming adapter and demo kits are avail- n 16mm 11.9mm 1.82mm LGA Package able. Applications running from 5V or supplying 5V IN AUX Readable Data: to SV should use LTM4686-1. Otherwise, use LTM4686: IN n Input and Output Voltages, Currents, and Temperatures MODULE PMBus COMMAND CODE LTM4686 LTM4686-1 n Running Peak Values, Uptime, Faults and Warnings 0x35, VIN ON (SV UVLO-Rising) 5.50V 4.25V IN n Onboard EEPROM Fault Log Record with ECC 0x36, VIN OFF (SV UVLO-Falling) 5.25V 4.00V IN Writable Data and Configurable Parameters: 0x58, VIN UV WARN LIMIT 5.30V 4.09V n Output Voltage, Voltage Sequencing and Margining Pb-free and RoHS compliant, the LTM4686 is available in n Digital Soft-Start/Stop Ramp a 16mm 11.9mm 1.82mm LGA package. n OV/UV/OT, UVLO, Frequency and Phasing All registered trademarks and trademarks are the property of their respective owners. Protected by U.S. Patents including 5408150, 5481178, 5705919, 5929620, 6144194, 6177787, 6580258, APPLICATIONS 7420359, 8163643. Licensed under U.S. Patent 7000125 and other related patents worldwide. n System Optimization in Prototype and Production Click to view associated Video Design Idea. Using PMBus and LTpowerPlay to Monitor Telemetry and Margin TYPICAL APPLICATION V /V During Load Pattern Tests. 10Hz Polling Rate. 3.3V OUT0 OUT1 IN Dual 10A Module Regulator with Digital Interface for Control and Monitoring* Input Current Readback Output Voltage Readback, V Margined 10% Low OUT 1.1 1.9 4 6 V , OUT0 V IN V V ADJUSTABLE IN0 OUT0 2.7V TO 5.5V UP TO 10A V IN1 1.0 1.8 22F + V OSNS0 SV 2 3 2 100F IN LOAD 0 4 0.9 1.7 LTM4686-1 LTC3204B-5, 5V OUT INTV V CC OSNS0 DC/DC CHARGE-PUMP 0.8 1.6 0 0 0 3 6 9 12 RUN 0 3 6 9 12 0 ON/OFF CONTROL TIME (s) 46861 TA01b TIME (s) 46861 TA01d RUN 1 V , OUT1 ADJUSTABLE V OUT1 Output Current Readback, Varying Load Pattern Power Stage Temperature Readback GPIO UP TO 10A FAULT INTERRUPTS, 0 10 10 60 60 V GPIO OSNS1 POWER SEQUENCING 1 100F LOAD 1 57 57 4 PWM CLOCK AND SYNC SGND 5 5 TIME-BASE SHARE CLK 54 54 SYNCHRONIZATION 2 SCL I C/SMBus I/F WITH SDA 0 0 51 51 REGISTER WRITE PMBus COMMAND SET WP 0 3 6 9 12 0 3 6 9 12 ALERT GND PROTECTION TO/FROM IPMI OR OTHER TIME (s) 46861 TA01c TIME (s) 46861 TA01e 46861 TA01a BOARD MANAGEMENT *FOR COMPLETE CIRCUIT, SEE FIGURE 29 CONTROLLER Rev. B 1 Document Feedback For more information www.analog.com V (V) OUT0 I (A) OUT0 CHANNEL 0 TEMP (C) I (A) IN0LTM4686/LTM4686-1 TABLE OF CONTENTS Features ..................................................... 1 Fault Detection and Handling ......................................55 Applications ................................................ 1 Open-Drain Pins ..........................................................55 Typical Application ........................................ 1 Phase-Locked Loop and Frequency Synchronization ..56 Description.................................................. 1 RCONFIG Pin-Straps (External Resistor Absolute Maximum Ratings .............................. 3 Configuration Pins) .................................................57 Order Information .......................................... 3 Voltage Selection ........................................................57 2 Pin Configuration .......................................... 3 Connecting the USB to the I C/SMBus/PMBus Electrical Characteristics ................................. 4 Controller to the LTM4686 In System .....................57 Typical Performance Characteristics .................. 11 LTpowerPlay: An Interactive GUI for Digital Power Pin Functions .............................................. 13 System Management ..............................................61 Simplified Block Diagram ............................... 18 PMBus Communication and Command Processing ....62 Decoupling Requirements ............................... 18 Thermal Considerations and Functional Diagram ...................................... 19 Output Current Derating .........................................63 Test Circuits ............................................... 20 EMI Performance ........................................................70 Operation................................................... 22 Safety Considerations .................................................70 Power Module Introduction .........................................22 Layout Checklist/Example ...........................................70 Power Module Configurability and Typical Applications ...................................... 72 Readback Data ........................................................ 24 Appendix A ................................................. 78 2 Time-Averaged and Peak Readback Data ....................26 Similarity Between PMBus, SMBus and I C Power Module Overview .............................................29 2-Wire Interface ......................................................78 EEPROM .....................................................................33 Appendix B ................................................. 79 Serial Interface ............................................................34 PMBus Serial Digital Interface ....................................79 Device Addressing ......................................................34 Appendix C: PMBus Command Details ................ 83 Fault Detection and Handling ......................................35 Addressing and Write Protect .....................................83 Responses to V and I Faults.............................36 General Configuration Registers .................................85 OUT OUT Responses to Timing Faults ........................................37 On/Off/Margin .............................................................86 Responses to SV OV Faults ......................................37 PWM Config ...............................................................88 IN Responses to OT/UT Faults .........................................37 Voltage ........................................................................90 Responses to External Faults .....................................37 Current ........................................................................93 Fault Logging ..............................................................38 Temperature ................................................................96 Bus Timeout Protection ..............................................38 Timing .........................................................................98 PMBus Command Summary ............................ 39 Fault Response ......................................................... 100 PMBus Commands ....................................................39 Fault Sharing ............................................................. 107 Applications Information ................................ 46 Scratchpad ................................................................ 109 V to V Step-Down Ratios ....................................49 Identification ............................................................. 109 IN OUT Input Capacitors ..........................................................49 Fault Warning and Status .......................................... 110 Output Capacitors .......................................................49 Telemetry .................................................................. 117 Light Load Current Operation ......................................49 NVM (EEPROM) Memory Commands ....................... 121 Switching Frequency and Phase .................................50 Package Description ................................... 128 Minimum On-Time Considerations ..............................52 Package Photographs .................................. 129 Variable Delay Time, Soft-Start and Output Voltage Package Description ................................... 130 Ramping .................................................................52 Revision History ........................................ 131 Digital Servo Mode .....................................................53 Typical Application ..................................... 132 Soft Off (Sequenced Off) ............................................54 Design Resources ...................................... 132 Undervoltage Lockout .................................................54 Related Parts ............................................ 132 Rev. B 2 For more information www.analog.com