Datasheet LTC3880, LTC3880-1 (Analog Devices) - 9

LTC3880/LTC3880-1
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 Digital Inputs SCL, SDA, RUN0, RUN1, GPIO0, GPIO1
VIH Input High Threshold Voltage SCL, SDA, RUN0, RUN1, GPIO0, GPIO1 l 2.0 V VIL Input Low Threshold Voltage SCL, SDA, RUN0, RUN1, GPIO0, GPIO1 l 1.4 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 l 1.5 1.8 V VIL Input Low Threshold Voltage l 0.6 1 V
Leakage Current SDA, SCL, ALERT, RUN0, RUN1
IOL Input Leakage Current 0V ≤ VPIN ≤ 5.5V l ±5 µA
Leakage Current GPIO0, GPIO1
IGL Input Leakage Current 0V ≤ VPIN < 3.6V l ±2 µA
Digital Filtering of GPIO0, GPIO1
IFLTG Input Digital Filtering GPIO 3 µs
Digital Filtering of RUN0, RUN1
IFLTG Input Digital Filtering RUN 10 µs
PMBus Interface Timing Characteristics
fSMB Serial Bus Operating Frequency l 10 400 kHz tBUF Bus Free Time Between Stop and Start l 1.3 µs tHD,STA Hold time After Repeated Start Condition. l 0.6 µs After this Period, the First Clock is Generated tSU,STA Repeated Start Condition Setup Time l 0.6 µs tSU,STO Stop Condition Setup Time l 0.6 µs tHD,DAT Data Hold Time Receiving Data l 0 µs Transmitting Data l 0.3 0.9 µs tSU,DAT Data Setup Time Receiving Data l 0.1 µs tTIMEOUT_SMB Stuck PMBus Timer Non-Block Reads Measured from the Last PMBus Start Event 32 ms Stuck PMBus Timer Block Reads 150 ms tLOW Serial Clock Low Period l 1.3 10000 µs tHIGH Serial Clock High Period l 0.6 µs Rev. H For more information www.analog.com 9 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 Power Up and Initialization Soft-Start Sequencing Voltage-Based Sequencing Shutdown Light Load Current Operation Switching Frequency and Phase Output Voltage Sensing Current Sensing Load Sharing External/Internal Temperature Sense RCONFIG (Resistor Configuration) Pins Fault Detection and Handling Internal Memory with CRC and ECC Serial Interface Communication Failure 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 Overtemperature Fault Response—Internal Overtemperature and Undertemperature Fault Response—Externals Responses to External Faults Bus Timeout Failure 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) 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 Connecting the USB to the I2C/SMBus/PMBus Controller to the LTC3880 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 Memory Commands Store/Restore Fault Log Operation Fault Logging Block Memory Write/Read Typical Applications Package Description Revision History Typical Application Related Parts