Datasheet LTC3887, LTC3887-1, LTC3887-2 (Analog Devices) - 8

LTC3887/LTC3887-1/ LTC3887-2
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the specified operating junction temperature range, otherwise specifications are at TA = 25°C. (Note 2) VIN = 12V, VRUN0,1 = 3.3V, fSYNC = 500kHz (externally driven) unless otherwise specified. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS INTVCC Regulator
VINTVCC Internal VCC Voltage No Load 6V < VIN < 24V 4.8 5 5.2 V (LTC3887, LTC3887-1) VLDO_INT INTVCC Load Regulation ICC = 0mA to 50mA 0.5 ±2 % (LTC3887, LTC3887-1)
VDD33 Regulator
VDD33 Internal VDD33 Voltage 4.5V < VINTVCC 3.2 3.3 3.4 V ILIM(VDD33) VDD33 Current Limit VDD33 = GND 70 mA VDD33_OV VDD33 Overvoltage Threshold 3.5 V VDD33_UV VDD33 Undervoltage Threshold 3.1 V
VDD25 Regulator
VDD25 Internal VDD25 Voltage 2.5 V ILIM(VDD25) VDD25 Current Limit VDD25 = GND 50 mA
Oscillator and Phase-Locked Loop
fOSC Oscillator Frequency Accuracy 250kHz < fSYNC < 1MHz Measured Falling l ±7.5 % Edge-to-Falling Edge of SYNC with SWITCH_ FREQUENCY = 250.0 and 1000.0 VTH,SYNC SYNC Input Threshold VCLKIN Falling 1 V VCLKIN Rising 1.5 V VOL,SYNC SYNC Low Output Voltage ILOAD = 3mA 0.2 0.4 V ILEAKSYNC SYNC Leakage Current in Slave Mode 0V ≤ VPIN ≤ 3.6V ±5 µA θSYNC-θ0 SYNC to Ch0 Phase Relationship Based on MFR_PWM_CONFIG_LTC3887[2:0] = 0, 2, 3 0 Deg the Falling Edge of Sync and Rising Edge of MFR_PWM_CONFIG_LTC3887[2:0] = 5 60 Deg TG0 MFR_PWM_CONFIG_LTC3887[2:0] = 1 90 Deg MFR_PWM_CONFIG_LTC3887[2:0] = 4, 6 120 Deg θSYNC-θ1 SYNC to Ch1 Phase Relationship Based on MFR_PWM_CONFIG_LTC3887[2:0] = 3 120 Deg the Falling Edge of Sync and Rising Edge of MFR_PWM_CONFIG_LTC3887[2:0] = 0 180 Deg TG1 MFR_PWM_CONFIG_LTC3887[2:0] = 2, 4, 5 240 Deg MFR_PWM_CONFIG_LTC3887[2:0] = 1 270 Deg MFR_PWM_CONFIG_LTC3887[2:0] = 6 300 Deg
EEPROM Characteristics
Endurance (Note 13) 0°C < TJ < 85°C During EEPROM Write l 10,000 Cycles Operations Retention (Note 13) TJ < TJMAX l 10 Years Mass_Write Mass Write Operation Time STORE_USER_ALL, 0°C < TJ < 85°C During l 440 4100 ms EEPROM Write Operations
Digital Inputs SCL, SDA, RUN0, RUN1, GPIO0, GPIO1
VIH Input High Threshold Voltage SCL, SDA, RUN0, RUN1, GPIO0, GPIO1 l 1.35 V VIL Input Low Threshold Voltage SCL, SDA, RUN0, RUN1, GPIO0, GPIO1 l 0.8 V VHYST Input Hysteresis SCL, SDA 0.08 V CPIN Input Capacitance 10 pF
Digital Input WP
IPUWP Input Pull-Up Current WP 10 µA
Open-Drain Outputs SCL, SDA, GPIO0, GPIO1, ALERT, RUN0, RUN1, SHARE_CLK
VOL Output Low Voltage ISINK = 3mA l 0.4 V
Digital Inputs SHARE_CLK, WP
VIH Input High Threshold Voltage 1.5 1.8 V VIL Input Low Threshold Voltage 0.6 1 V
Leakage Current SDA, SCL, ALERT, RUN0, RUN1
IOL Input Leakage Current 0V ≤ VPIN ≤ 5.5V l ±5 µA Rev.F 8 For more information www.analog.com Document Outline Features Applications Typical Application Description Table of Contents Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Overview Main Control Loop EEPROM (NVM) Power Up and Initialization Soft-Start Sequencing EVENT-Based Sequencing Shutdown Light Load Current Operation Switching Frequency and Phase Output Voltage Sensing Current Sensing PolyPhase Load Sharing External/Internal Temperature Sense RCONFIG (Resistor Configuration) Pins Fault Detection and Handling Internal EEPROM with CRC Protection and ECC Serial Interface Communication Protection Device Addressing Responses to VOUT and 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/Warn Response External Overtemperature and Undertemperature Fault Response Responses to External Faults Fault Logging Bus Timeout Protection Similarity Between PMBus, SMBus and I2C 2-Wire Interface PMBus Serial Digital Interface PMBus Command Summary PMBus Commands *Data Format Applications Information Current Limit Programming ISENSE+ and ISENSE– Pins Low Value Resistor Current Sensing Inductor DCR Current Sensing Slope Compensation and Inductor Peak Current Inductor Value Calculation Inductor Core Selection Power MOSFET and Schottky Diode (Optional) Selection Variable Delay Time, Soft-Start and Output Voltage Ramping Digital Servo Mode Soft Off (Sequenced Off) INTVCC Regulator Topside MOSFET Driver Supply (CB, DB) (LTC3887, LTC3887-2) Undervoltage Lockout CIN and COUT Selection Fault Conditions Open-Drain Pins Phase-Locked Loop and Frequency Synchronization Minimum On-Time Considerations RCONFIG (External Resistor Configuration Pins) Voltage Selection Frequency and Phase Selection Using RCONFIG Address Selection Using RCONFIG Efficiency Considerations Checking Transient Response PC Board Layout Checklist PC Board Layout Debugging Design Example Additional Design Checks Connecting the USB to the I2C/SMBus/PMBus Controller to the LTC3887 In System LTpowerPlay: An Interactive GUI for Digital Power PMBus Communication and Command Processing PMBus Command Details Addressing and Write Protect General Configuration Registers On/Off/Margin PWM Config Voltage Input Voltage and Limits Output Voltage and Limits Current Input Current Calibration Output Current Calibration Input Current Output Current Temperature External Temperature Calibration External Temperature Limits 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 Telemetry NVM (EEPROM) Memory Commands Store/Restore Fault Logging Block Memory Write/Read Typical Applications Package Description Revision History Typical Application Related Parts