link to page 45 link to page 45 link to page 45 link to page 45 link to page 45 link to page 50 link to page 51 link to page 51 link to page 51 link to page 51 link to page 51 link to page 52 link to page 53 link to page 54 link to page 54 link to page 54 link to page 54 link to page 55 link to page 56 link to page 56 link to page 56 link to page 57 link to page 57 link to page 58 link to page 58 link to page 59 link to page 60 link to page 60 link to page 60 link to page 61 link to page 61 link to page 61 link to page 63 link to page 63 link to page 66 link to page 66 link to page 66 link to page 66 link to page 67 link to page 67 link to page 67 link to page 68 link to page 68 link to page 68 link to page 68 link to page 69 link to page 70 link to page 70 link to page 70 link to page 72 link to page 77 link to page 77 link to page 79 link to page 80 link to page 82 link to page 85 link to page 85 link to page 86 link to page 89 link to page 91 link to page 92 link to page 92 link to page 93 link to page 93 link to page 94 link to page 95 link to page 95 link to page 95 link to page 96 link to page 96 link to page 99 link to page 100 link to page 101 link to page 102 link to page 102 link to page 104 link to page 104 link to page 105 link to page 106 link to page 113 link to page 117 link to page 117 link to page 118 link to page 122 link to page 123 link to page 123 link to page 126 link to page 126 link to page 126 LTM4680 TABLE OF CONTENTS PMBus Command Summary ..45 Derating Curves ..69 PMBus Commands ..45 EMI Performance ...70 Table 7. PMBus Commands Summary (Note: The Safety Considerations ..70 Data Format Abbreviations Are Detailed in Layout Checklist/Example ...70 Table 8) ..45 Typical Applications ..72 Table 8. Data Format Abbreviations ...50 PMBus Command Details ...77Applications Information ..51 Addressing and Write Protect ...77 VIN to VOUT Step-Down Ratios ...51 General Configuration Commands ..79 Input Capacitors .. 51 On/Off/Margin ..80 Output Capacitors .. 51 PWM Configuration ..82 Light Load Current Operation ... 51 Voltage ..85 Switching Frequency and Phase ..52 Input Voltage and Limits ...85 Output Current Limit Programming ...53 Output Voltage and Limits ..86 Minimum On-Time Considerations ...54 Output Current and Limits ..89 Variable Delay Time, Soft-Start and Output Voltage Input Current and Limits ..91 Ramping ..54 Temperature ..92 Digital Servo Mode ..54 Power Stage DCR Temperature Calibration...92 Soft Off (Sequenced Off) ...55 Timing ..93 Undervoltage Lockout ..56 Timing—On Sequence/Ramp ...93 Fault Detection and Handling ...56 Timing—Off Sequence/Ramp ..94 Open-Drain Pins ..56 Precondition for Restart ...95 Phase-Locked Loop and Frequency Fault Response ...95 Synchronization ...57 Fault Responses Al Faults ..95 Input Current Sense Amplifier ..58 Fault Responses Input Voltage ...96 Programmable Loop Compensation ..58 Fault Responses Output Voltage ...96 Checking Transient Response ..59 Fault Responses Output Current ...99 PolyPhase Configuration ...60 Fault Responses IC Temperature .. 100 Connecting The USB to I2C/SMBus/PMBus Fault Responses External Temperature ... 101 Control er to the LTM4680 In System ..60 Fault Sharing ... 102 LTpowerPlay: An Interactive GUI for Digital Power .61 Fault Sharing Propagation .. 102 PMBus Communication and Command Fault Sharing Response .. 104 Processing ...61 Scratchpad ... 104 Thermal Considerations and Output Current Identification ... 105 Derating ...63 Fault Warning and Status .. 106 Tables 10 thru 11: Output Current Derating ...66 Telemetry .. 112 Table 12. Channel Output Voltage vs Capacitor NVM Memory Commands .. 116 Selection, All Ceramic Configuration, 15A to 30A Store/Restore ... 116 Load Step with 15A/µs Slew Rate ..66 Fault Logging .. 117 Table 13. Channel Output Voltage vs Capacitor Block Memory Write/Read .. 121 Selection, Bulk and Ceramic Cap Configuration, Package Description ... 122 15A to 30A Load Step with 15A/µs Slew Rate ...67 Table 23. LTM4680 BGA Pinout .. 122 Table 14. Dual Phase Single Output Voltage vs Package Photograph ... 124 Capacitor Selection, Bulk and Ceramic Cap Design Resources .. 124 Configuration, 30A to 60A Load Step with 30A/µs Related Parts .. 124 Slew Rate ..68 Rev. A For more information www.analog.com 3 Document Outline Features Applications Typical Application Description Table of Contents Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Simplified Block Diagram Decoupling Requirements Functional Diagram Test Circuits Operation Power Module Introduction Power Module Overview, Major Features EEPROM with ECC Power-Up and Initialization Soft-Start Time-Based Sequencing Voltage-Based Sequencing Shutdown Light-Load Current Operation Switching Frequency and Phase PWM Loop Compensation Output Voltage Sensing INTVCC/EXTVCC Power Output Current Sensing and Sub Milliohm DCR Current Sensing Input Current Sensing PolyPhase Load Sharing External/Internal Temperature Sense RCONFIG (Resistor Configuration) Pins Table 1. VOUTn_CFG Pin Strapping Look-Up Table for the LTM4680’s Output Voltage, Coarse Setting (Not Applicable if MFR_CONFIG_ALL[6] = 1b) Table 2. VTRIMn_CFG Pin Strapping Look-Up Table for the LTM4680’s Output Voltage, Fine Adjustment Setting (Not Applicable if MFR_CONFIG_ALL[6] = 1b) Table 3. FSWPH_CFG Pin Strapping Look-Up Table to Set the LTM4680’s Switching Frequency and Channel Phase-Interleaving Angle (Not Applicable if MFR_CONFIG_ALL[6] = 1b) Table 4. ASEL Pin Strapping Look-Up Table to Set the LTM4680’s Slave Address (Applicable Regardless of MFR_CONFIG_ALL[6] Setting) Table 5. LTM4680 MFR_ADDRESS Command Examples Expressed in 7- and 8-Bit Addressing Fault Detection and Handling Status Registers and ALERT Masking Figure 5. LTM4680 Status Register Summary Mapping Faults to FAULT Pins Power Good Pins CRC Protection Serial Interface Communication Protection Device Addressing Responses to VOUT and IIN/IOUT Faults Output Overvoltage Fault Response Output Undervoltage Response Peak Output Overcurrent Fault Response Responses to Timing Faults Responses to VIN OV Faults Responses to OT/UT Faults Internal Overtemperature Fault Response External Overtemperature and Undertemperature Fault Response Responses to Input Overcurrent and Output Undercurrent Faults Responses to External Faults Fault Logging Bus Timeout Protection Similarity Between PMBus, SMBus and I2C 2-Wire Interface PMBus Serial Digital Interface Table 6. Abbreviations of Supported Data Formats Figure 6. PMBus Timing Diagram Figures 7 to 24 PMBus Protocols PMBus Command Summary PMBus Commands Table 7. PMBus Commands Summary (Note: The Data Format Abbreviations Are Detailed in Table 8) Table 8. Data Format Abbreviations Applications Information VIN to VOUT Step-Down Ratios Input Capacitors Output Capacitors Light Load Current Operation Switching Frequency and Phase Output Current Limit Programming Minimum On-Time Considerations Variable Delay Time, Soft-Start and Output Voltage Ramping Digital Servo Mode Soft Off (Sequenced Off) Undervoltage Lockout Fault Detection and Handling Open-Drain Pins Phase-Locked Loop and Frequency Synchronization Input Current Sense Amplifier Programmable Loop Compensation Checking Transient Response PolyPhase Configuration Connecting The USB to I2C/SMBus/PMBus Controller to the LTM4680 In System LTpowerPlay: An Interactive GUI for Digital Power PMBus Communication and Command Processing Thermal Considerations and Output Current Derating Tables 10 thru 11: Output Current Derating Table 12. Channel Output Voltage vs Capacitor Selection, All Ceramic Configuration, 15A to 30A Load Step with 15A/µs Slew Rate Table 13. Channel Output Voltage vs Capacitor Selection, Bulk and Ceramic Cap Configuration, 15A to 30A Load Step with 15A/µs Slew Rate Table 14. Dual Phase Single Output Voltage vs Capacitor Selection, Bulk and Ceramic Cap Configuration, 30A to 60A Load Step with 30A/µs Slew Rate Derating Curves EMI Performance Safety Considerations Layout Checklist/Example Typical Applications PMBus Command Details Addressing and Write Protect General Configuration Commands On/Off/Margin PWM Configuration Voltage Input Voltage and Limits Output Voltage and Limits Output Current and Limits Input Current and Limits Temperature Power Stage DCR Temperature Calibration Timing Timing—On Sequence/Ramp Timing—Off Sequence/Ramp Precondition for Restart Fault Response Fault Responses All Faults Fault Responses Input Voltage Fault Responses Output Voltage Fault Responses Output Current Fault Responses IC Temperature Fault Responses External Temperature Fault Sharing Fault Sharing Propagation Fault Sharing Response Scratchpad Identification Fault Warning and Status Telemetry NVM Memory Commands Store/Restore Fault Logging Block Memory Write/Read Package Description Table 23. LTM4680 BGA Pinout Package Photograph Design Resources Related Parts
