Datasheet LTM4678 (Analog Devices) - 8

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ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the specified internal operating temperature range (Note 2). Specified as each individual output channel (Note 4). TA = 25°C, VIN = 12V, RUNn = 3.3V, EXTVCC = 0, FREQUENCY_SWITCH = 350kHz and VOUTn commanded to 1.000V unless otherwise noted. Configured with factory-default EEPROM settings and per Test Circuit 1, unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
IO-F/S Output Current Full-Scale (Note 12) 40 A Digitizable Range Utilizing MFR_PWM_MODE[7] = 1, Using IOUT_OC_FAULT_ LIMIT = 34A, Page 90 IO-RB-ACC Output Current, Readback Accuracy READ_IOUTn, Channels 0 and 1, 0 ≤ IOUTn ≤ 25A, (Note 12) l Within 1.25A of Reading Forced-Continuous Mode, MFR_PWM_MODEn[1:0] = 1b IO-RB(25A) Full Load Output Current Readback IOUTn = 25A (Note 12). See Histograms in Typical 25 A Performance Characteristics (Note 12) tCONVERT-IO-RB Output Current Readback Update MFR_ADC_CONTROL = 0x00 (Notes 9, 15) 90 ms Rate MFR_ADC_CONTROL = 0x06 (CH0 IOUT) or 0x01 (CH1 IOUT) 8 ms (Notes 9, 15) See MFR_ADC_CONTROL Section
Input Current Readback
N Resolution (Note 10) 10 Bits V + – IINSTP LSB Step Size Full-Scale Range = Gain = 8, 0V ≤ |VIIN – VIIN | ≤ 5mV 15.26 µV 16mV Gain = 4, 0V ≤ |V + – IIN – VIIN | ≤ 20mV 30.52 µV LSB Step Size Full-Scale Range = Gain = 2, 0V ≤ |V + – IIN – VIIN | ≤ 50mV 61 µV 32mV LSB Step Size Full-Scale Range = 64mV I + – IN_TUE Total Unadjusted Error Gain = 8, 2.5mV ≤ |VIIN – VIIN | l ±2 % Gain = 4, 4mV ≤ |V + – IIN – VIIN | l ±1.3 % Gain = 2, 6mV ≤ |V + – IIN – VIIN | l ±1.2 % VOS Zero-Code Offset Voltage (Note 15) ±50 µV tCONVERT Update Rate (Notes 9,15) See MFR_ADC_CONTROL Section for Faster 90 ms Update Rates
Supply Current Readback
N Resolution (Note 10) 10 Bits VICHIPSTP LSB Step Size Full-Scale Range = Onboard 1Ω Resistor 244 µV 256mV ICHIP-RB ICHIP Readback SVIN Curent ±50 mA tCONVERT Update Rate (Notes 9,15) See MFR_ADC_CONTROL Section for Faster 90 ms Update Rates
Temperature Readback (T0, T1)
TRES-RB Temperature Readback Resolution Channel 0, Channel 1, and Controller (Note 15) 0.25 °C T0_TUE External Temperature Total Supporting Only ∆VBE Sensing Unadjusted Readback Error ±5 °C °C T1_TUE Internal TSNS TUE VRUN0,1 = 0.0, fSYNC = 0kHz (Note 15) l ±1 °C tCONVERT Update Rate (Note 9) 90 ms MFR_ADC_CONTROL = 0x04 or 0x0C (Notes 9, 15) 8 ms
INTVCC Regulator/EXTVCC
VINTVCC Internal VCC Voltage No Load 6V ≤ VIN ≤ 16V l 5.25 5.5 5.75 V VLDO_INT INTVCC Load Regulation ICC = 0mA to 20mA, 6V ≤ VIN ≤ 16V 0.5 ±2 % VEXTVCC EXTVCC Switchover Voltage VIN ≥ 7V, EXTVCC Rising l 4.5 4.7 4.9 V VLDO_HYS EXTVCC Hysteresis 290 mV VLDO_EXT EXTVCC Voltage Drop ICC = 20mA, VEXTVCC = 5.5V 80 120 mV Rev 0 8 For more information www.analog.com Document Outline Functional Diagram 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 LTM4678’s Output Voltage, Coarse Setting (Not Applicable if MFR_CONFIG_ALL[6] = 1b) Table 2. VTRIMn_CFG Pin Strapping Look-Up Table for the LTM4678’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 LTM4678’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 LTM4678’s Slave Address (Applicable Regardless of MFR_CONFIG_ALL[6] Setting) Table 5. LTM4678 MFR_ADDRESS Command Examples Expressed in 7- and 8-Bit Addressing Fault Detection and Handling Status Registers and ALERT Masking Figure 5. LTM4678 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 LTM4678 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 Component Selection, 0A to 12.5A/μs Load Step Output Capacitor-GRM32ER60G337ME05L, 330μF, 4V, X5R, Murata Table 13. Channel Output Voltage vs Component Selection, 0A to 12.5A/μs Load Step Dual Phase Single Output Voltage vs Component Selection, 25A to 50A/μs Load Step Applications Information-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 MFR_INFO Data Contents: Telemetry NVM Memory Commands Store/Restore Fault Logging Block Memory Write/Read Package Description Table 22. LTM4678 BGA Pinout Typical Applications Design Resources Related Parts