LTM4686/LTM4686-1 ELECTRICALCHARACTERISTICS The l denotes the specifications which apply over the specified internaloperating temperature range (Note 2). Specified as each individual output channel (Note 4). TA = 25°C, VIN = 12V, RUNn= 5V,FREQUENCY_SWITCH = 500kHz, VOUT_COMMANDn= 1V and VOUT_UV_FAULT_RESPONSEn= TON_MAX_FAULT_RESPONSEn= 0x00unless otherwise noted. All other command codes configured per factory-default EEPROM settings unless otherwise noted. Tested perCircuit 1, unless otherwise noted. SYMBOLPARAMETERCONDITIONSMINTYPMAX UNITS tCONVERT-VO-RB Output Voltage MFR_ADC_CONTROL=0x00 (Notes 9, 15) 90 ms Readback Update Rate MFR_ADC_CONTROL=0x0D (Notes 9, 15) 27 ms MFR_ADC_CONTROL=0x05 or 0x09 (Notes 9, 15) 8 ms Input Voltage (SVIN) Readback (READ_VIN) NSVIN-RB Input Voltage (Notes 10, 15) 10 Bits Readback Resolution 15.625 mV and LSB Step Size SVIN-F/S Input Voltage Full- (Notes 11, 15) 38.91 V Scale Digitizable Range SVIN-RB-ACC Input Voltage READ_VIN, 4.5V ≤ SVIN ≤ 17V l Within ±2% of Reading Readback Accuracy tCONVERT-SVIN-RB Input Voltage MFR_ADC_CONTROL=0x00 (Notes 9, 15) 90 ms Readback Update Rate MFR_ADC_CONTROL=0x01 (Notes 9, 15) 8 ms Channels 0 and 1 Output Current (READ_IOUTn), Duty Cycle (READ_DUTY_CYCLEn), and Computed Input Current (MFR_READ_IINn) Readback NIO-RB Output Current (Notes 10, 12) 10 Bits Readback Resolution 15.6 mA and LSB Step Size IO-F/S, II-F/S Output Current (Note 12) ±40 A Full-Scale Digitizable Range and Input Current Range of Calculation IO-RB-ACC Output Current, READ_IOUTn, Channels 0 and 1, 0 ≤ IOUTn ≤ 10A, l Within 500mA of Reading Readback Accuracy Forced-Continuous Mode, MFR_PWM_MODEn[0] = 1b FREQUENCY_SWITCH = 350kHz IO-RB(10A) Full Load Output IOUTn = 10A (Note 12). See Histograms in Typical Performance 10 A Current Readback Characteristics NII-RB Computed Input (Notes 10, 12) 10 Bits Current, Readback 1.95 mA Resolution and LSB Step Size II-RB-ACC Computed Input MFR_READ_IINn, Channels 0 and 1, 0 ≤ IOUTn ≤ 10A, l Within 150mA of Reading Current, Readback Forced-Continuous Mode, MFR_PWM_MODEn[0] = 1b, Accuracy, Neglecting MFR_IIN_OFFSETn = 0mA ISVIN tCONVERT-IO-RB Output Current MFR_ADC_CONTROL=0x00 (Notes 9, 15) 90 ms Readback Update Rate MFR_ADC_CONTROL=0x0D (Notes 9, 15) 27 ms MFR_ADC_CONTROL=0x06 or 0x0A (Notes 9, 15) 8 ms tCONVERT-II-RB Computed Input MFR_ADC_CONTROL=0x00 (Notes 9, 15) 90 ms Current, Readback Update Rate NDUTY-RB Resolution, Duty Cycle (Notes 10, 15) 10 Bits Readback DRB-ACC Duty Cycle TUE READ_DUTY_CYCLEn, 16.3% Duty Cycle (Note 15) ±3 % tCONVERT-DUTY-RB Duty Cycle Readback MFR_ADC_CONTROL=0x00 (Notes 9, 15) 90 ms Update Rate Rev. B For more information www.analog.com 7 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