Datasheet LTM4686, LTM4686-1 (Analog Devices) - 2

link to page 1 link to page 1 link to page 1 link to page 1 link to page 3 link to page 3 link to page 3 link to page 4 link to page 11 link to page 13 link to page 18 link to page 18 link to page 19 link to page 20 link to page 22 link to page 22 link to page 24 link to page 24 link to page 26 link to page 29 link to page 33 link to page 34 link to page 34 link to page 35 link to page 36 link to page 37 link to page 37 link to page 37 link to page 37 link to page 38 link to page 38 link to page 39 link to page 39 link to page 46 link to page 49 link to page 49 link to page 49 link to page 49 link to page 50 link to page 52 link to page 52 link to page 52 link to page 53 link to page 54 link to page 54 link to page 55 link to page 55 link to page 56 link to page 57 link to page 57 link to page 57 link to page 57 link to page 57 link to page 61 link to page 61 link to page 62 link to page 63 link to page 63 link to page 70 link to page 70 link to page 70 link to page 72 link to page 78 link to page 78 link to page 78 link to page 79 link to page 79 link to page 83 link to page 83 link to page 85 link to page 86 link to page 88 link to page 90 link to page 93 link to page 96 link to page 98 link to page 100 link to page 107 link to page 109 link to page 109 link to page 110 link to page 117 link to page 121 link to page 128 link to page 129 link to page 130 link to page 131 link to page 132 link to page 132 link to page 132 LTM4686/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
Pin Configuration .. 3
Connecting the USB to the I2C/SMBus/PMBus
Electrical Characteristics ... 4
Control er 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
Time-Averaged and Peak Readback Data ..26 Similarity Between PMBus, SMBus and I2C 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 VOUT and IOUT Faults...36 General Configuration Registers ...85 Responses to Timing Faults ..37 On/Off/Margin ...86 Responses to SVIN OV Faults ..37 PWM Config ...88 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 VIN to VOUT Step-Down Ratios ..49 Identification ... 109 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 Document Outline Features Applications Typical Application Description 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 Configurability and Readback Data Time-Averaged and Peak Readback Data Power Module Overview EEPROM Serial Interface Device Addressing Fault Detection and Handling Responses to VOUT and IOUT Faults Responses to Timing Faults Responses to SVIN OV Faults Responses to OT/UT Faults Responses to External Faults Fault Logging Bus Timeout Protection PMBus Command Summary PMBus Commands Applications Information VIN to VOUT Step-Down Ratios Input Capacitors Output Capacitors Light Load Current Operation Switching Frequency and Phase 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 RCONFIG Pin-Straps (External Resistor Configuration Pins) Voltage Selection Connecting the USB to the I2C/SMBus/PMBus Controller to the LTM4686 In System LTpowerPlay: An Interactive GUI for Digital Power System Management PMBus Communication and Command Processing Thermal Considerations and Output Current Derating EMI Performance Safety Considerations Layout Checklist/Example Typical Applications Appendix A Similarity Between PMBus, SMBus and I2C 2-Wire Interface Appendix B PMBus Serial Digital Interface Appendix C: PMBus Command Details Addressing and Write Protect General Configuration Registers On/Off/Margin PWM Config Voltage Current Temperature Timing Fault Response Fault Sharing Scratchpad Identification Fault Warning and Status Telemetry NVM (EEPROM) Memory Commands Package Description Package Photographs Package Description Revision History Typical Application Design Resources Related Parts