Datasheet LTM4678 (Analog Devices) - 5

link to page 89 LTM4678
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the specified internal operating temperature range (Note 2). n is 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
VINn, SVIN Input DC Voltage Test Circuit 1 l 5.75 16 V Test Circuit 2; VIN_OFF < VIN_ON = 4V l 4.5 5.75 V V + – OUTn Range of Output Voltage Regulation VOUT0 Differentially Sensed on VOSNS0 /VOSNS0 Pin-Pair; l 0.5 3.4 V V + – OUT1 Differentially Sensed on VOSNS1 /VOSNS1 Pin-Pair; l 0.5 3.4 V Commanded by Serial Bus or with Resistors Present at Start- Up on VOUTn_CFG (Note 19) VOUTn(DC) Output Voltage, Total Variation with (Note 5) Line and Load Digital Servo Engaged (MFR_PWM_MODEn[6] = 1b) 0.995 1.000 1.005 V Digital Servo Disengaged (MFR_PWM_MODEn[6] = 0b) l 0.985 1.000 1.015 V VOUTn Commanded to 1.000V, VOUTn Low Range (MFR_PWM_MODEn[1] = 1b) VUVLO Undervoltage Lockout Threshold, VINTVCC Falling 3.55 V When VIN < 4.3V VINTVCC Rising 3.90 V
Input Specifications
IINRUSH(VIN) Input Inrush Current at Test Circuit 1, VOUTn =1V, VIN = 12V; No Load Besides 400 mA Start-Up Capacitors; TON_RISEn = 3ms IQ(SVIN) Input Supply Bias Current Forced Continuous Mode, MFR_PWM_MODEn[0] = 1b RUNn = 3.3V 25 mA Shutdown, RUN0 = RUN1 = 0V (Note 16) 23 mA IS(VINn,PSM) Input Supply Current in Pulse- Pulse-Skipping Mode, MFR_PWM_MODEn[0] = 0b, 20 mA Skipping Mode Operation IOUTn = 100mA IS(VINn,FCM) Input Supply Current in Forced- Forced Continuous Mode, MFR_PWM_MODEn[0] = 1b Continuous Mode Operation IOUTn = 100mA 50 mA IOUTn = 25A 2.4 A
Output Specifications
IOUTn Output Continuous Current Range (Note 6) Utilizing MFR_PWM_MODE[7] = 1 and 0 25 A Using ~IOUT = 36A for IOUT_OC_FAULT_LIMIT, Page 89 ∆VOUTn(LINE) Line Regulation Accuracy Digital Servo Engaged (MFR_PWM_MODEn[6] = 1b) 0.03 %/V V Digital Servo Disengaged (MFR_PWM_MODEn[6] = 0b) l 0.03 ±0.2 %/V OUTn SVIN and VINn Electrically Shorted Together and INTVCC Open Circuit; IOUTn = 0A, 5.75V ≤ VIN ≤ 16V, VOUT Low Range (MFR_PWM_MODEn[1] = 1b), FREQUENCY_SWITCH = 350kHz (Note 5) ∆VOUTn(LOAD) Load Regulation Accuracy Digital Servo Engaged (MFR_PWM_MODEn[6] = 1b) 0.03 % Digital Servo Disengaged (MFR_PWM_MODEn[6] = 0b) l 0.2 0.5 % VOUTn 0A ≤ IOUTn ≤ 25A, VOUT Low Range, (MFR_PWM_MODEn[1] = 1b) (Note 5) VOUTn(AC) Output Voltage Ripple 10 mVP-P fS (Each VOUTn Ripple Frequency FREQUENCY_SWITCH Set to 350kHz (0xFABC) l 325 350 375 kHz Channel) ∆VOUTn(START) Turn-On Overshoot TON_RISEn = 3ms (Note 12) 8 mV tSTART Turn-On Start-Up Time Time from VIN Toggling from 0V to 12V to Rising Edge l 30 ms PGOODn. TON_DELAYn = 0ms, TON_RISEn = 3ms tDELAY(0ms) Turn-On Delay Time Time from First Rising Edge of RUNn to Rising Edge of l 2.95 3.3 3.7 ms PGOODn . TON_DELAYn = 0ms, TON_RISEn = 3ms, VIN Having Been Established for at Least 70ms ∆VOUTn(LS) Peak Output Voltage Deviation for Load: 0A to 12.5A and 12.5A to 0A at 12.5A/µs, 50 mV Dynamic Load Step VOUTn = 1V, VIN = 12V (Note 12) See Load Transient Graphs Rev. A For more information www.analog.com 5 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 VOUTn _CFG Pin Strapping Look-Up Table for the LTM4678’s Output Voltage, Coarse Setting (Not Applicable if MFR_CONFIG_ALL[6] = 1b) VTRIMn_CFG Pin Strapping Look-Up Table for the LTM4678’s Output Voltage, Fine Adjustment Setting (Not Applicable if MFR_CONFIG_ALL[6] = 1b) 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) ASEL Pin Strapping Look-Up Table to Set the LTM4678’s Slave Address (Applicable Regardless of MFR_CONFIG_ALL[6] Setting) LTM4678 MFR_ADDRESS Command Examples Expressed in 7- and 8-Bit Addressing Fault Detection and Handling Status Registers and ALERT Masking 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 Abbreviations of Supported Data Formats Figure 7 to Figure 24 PMBus Protocols PMBus Command Summary PMBus Commands PMBus Commands Summary (Note: The Data Format Abbreviations are Detailed in 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 Recommended Switching Frequency for Various VIN-to-VOUT Step-Down Scenarios 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 Table 10 thru Table 11: Output Current Derating 0.9V Output 1.8V Output Channel Output Voltage vs Component Selection, 0A to 12.5A/μs Load Step Output Capacitor-GRM32ER60G337ME05L, 330μF, 4V, X5R, Murata Low VOUT Range for VOUT ≤ 2.5V High VOUT Range for 2.5V ≤ VOUT ILIMIT Range = High Channel Output Voltage vs Component Selection, 0A to 12.5A/μs Load Step Low VOUT Range for VOUT ≤ 2.5V High VOUT Range for 2.5V ≤ VOUT ILIMIT Range = High Dual Phase Single Output – Ceramic and Poscap Output Capacitors 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 VOUT_OV_FAULT_RESPONSE Data Byte Contents VOUT_UV_FAULT_RESPONSE Data Byte Contents Fault Responses Output Current OUT_OC_FAULT_RESPONSE Data Byte Contents Fault Responses IC Temperature Data Byte Contents MFR_OT_FAULT_RESPONSE Fault Responses External Temperature Fault Sharing Fault Sharing Propagation FAULTn Propagate Fault Configuration Fault Sharing Response Scratchpad Identification Fault Warning and Status Telemetry NVM Memory Commands Store/Restore Fault Logging Fault Logging Explanation of Position_Fault Values Block Memory Write/Read Package Description LTM4678 BGA Pinout Revision History Package Photograph Design Resources Related Parts