Datasheet LTM4678 (Analog Devices) - 9

LTM4678
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
VIN_THR VIN Threshold to Enable EXTVCC VIN Rising 7 7.4 V Switchover VIN_THF VIN Hysteresis to Disable EXTVCC VIN Falling 600 mV Switchover
VDD33 Regulator
VVDD33 Internal VDD33 Voltage 4.5V < VINTVCC or 4.8V < VEXTVCC 3.2 3.3 3.4 V ILIM VDD33 Current Limit VDD33 = GND 100 mA VVDD33_OV VDD33 Overvoltage Threshold 3.5 V VVDD33_UV VDD33 Undervoltage Threshold 3.1 V
VDD25 Regulator
VVDD25 Internal VDD25 Voltage 2.5 V ILIM VDD25 Current Limit VDD25 = GND 80 mA
Oscillator and Phase-Locked Loop (PLL)
fRANGE PLL SYNC Range Synchronized with Falling Edge of SYNC l 300 1075 kHz fOSC Oscillator Frequency Accuracy Frequency Switch = 350.0kHz to 1000.0kHz (Note 15) ±7.5 % VTH(SYNC) SYNC Input Threshold VSYNC Falling 1 V VSYNC Rising 1.5 V VOL(SYNC) SYNC Low Output Voltage ILOAD = 3mA 0.2 0.4 V ILEAK(SYNC) SYNC Leakage Current in Slave 0V ≤ VPIN ≤ 3.6V ±5 µA Mode θSYNC-θ0 SYNC to Ch0 Phase Relationship MFR_PWM_CONFIG[2:0] = 0,2,3 0 Deg Based on the Falling Edge of Sync MFR_PWM_CONFIG[2:0] = 5 60 Deg and Rising Edge of TG0 (Note 15) MFR_PWM_CONFIG[2:0] = 1 90 Deg MFR_PWM_CONFIG[2:0]= 4,6 120 Deg θSYNC-θ1 SYNC to Ch1 Phase Relationship MFR_PWM_CONFIG[2:0] = 3 120 Deg Based on the Falling Edge of Sync MFR_PWM_CONFIG[2:0] = 0 180 Deg and Rising Edge of TG1 (Note 15) MFR_PWM_CONFIG[2:0] = 2,4,5 240 Deg MFR_PWM_CONFIG[2:0] = 1 270 Deg MFR_PWM_CONFIG[2:0] = 6 300 Deg
EEPROM Characteristics
Endurance (Notes 13 and 17) 0°C ≤ TJ ≤ 85°C During EEPROM Write Operations l 10,000 Cycles Retention (Notes 13 and 17) TJ < 125°C l 10 Years Mass_Write Mass Write Operation Time STORE_USER_ALL, 0°C < TJ < 85°C 440 4100 ms (Notes 13 and 17) During EEPROM Write Operation
Leakage Current SDA, SCL, ALERT, RUN
IOL Input Leakage Current OV ≤ VPIN ≤ 5.5V l ±5 µA
Leakage Current FAULTn , PGOODn
IGL Input Leakage Current OV ≤ VPIN ≤ 3.6V l ±2 µA
Digital Inputs SCL, SDA, RUNn , GPI0n (Note 15)
VIH Input High Threshold Voltage l 1.35 V VIL Input Low Threshold Voltage l 0.8 V VHYST Input Hysteresis SCL, SDA 0.08 V CPIN Input Capacitance 10 pF Rev 0 For more information www.analog.com 9 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