Datasheet LTC3889 (Analog Devices) - 5

LTC3889
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the specified operating junction temperature range, otherwise specifications are at TJ = 25°C (Note 2). VIN = 16V, EXTVCC = 0V, VRUN0 = 1.8V, VRUN1 = 1.8V fSYNC = 250kHz (externally driven), and all programmable parameters at factory default unless otherwise specified. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Input Voltage
VIN Input Voltage Range (Note 12) l 5 60 V IQ Input Voltage Supply Current (Note 14) Normal Operation VRUN = 3.3V, No Caps on TG and BG 26 mA VRUN = 0V 20 mA VUVLO Undervoltage Lockout Threshold VDRVCC Falling 3.7 V When VIN > 4.2V VDRVCC Rising 3.95 V TINIT Initialization Time Delay from RESTORE_USER_ALL, 35 ms MFR_REST, or VDRVCC > VUVLO Until TON_DELAY Can Begin
Control Loop
VOUTR0 Range 0 Maximum VOUT 40 V Range 0 Set Point Accuracy 6V ≤ VOUT ≤ 38V l –0.5 0.5 % Range 0 Resolution 12 Bits Range 0 LSB Step Size, FSR = 41.48V (Notes 9, 10) 10 mV VOUTR1 Range 1 Maximum VOUT 8 V Range 1 Set Point Accuracy 3V ≤ VOUT ≤ 8V l –0.5 0.5 % Range 1 Resolution 12 Bits Range 1 LSB Step Size, FSR = 8.30V (Notes 9, 10) 2 mV VLINEREG Line Regulation 16V < VIN < 60V l ±0.02 %/V VLOADREG Load Regulation ∆VITH = 1.35V – 0.7V l 0.01 0.1 % ∆VITH = 1.35V – 2.0V l –0.01 –0.1 % gm0,1 Resolution 3 bits Error Amplifier gm(MAX) ITH =1.35V 5.76 mmho Error Amplifier gm(MIN) ITH =1.35V 1.00 mmho Error Amplifier gm LSB Step Size ITH =1.35V 0.68 mmho RITHR0,1 Resolution 5 bits Compensation Resistor RITHR(MAX) 62 kΩ Compensation Resistor RITHR(MIN) 0 kΩ IISENSE Input Current VISENSE = 40V l ±1 ±2 µA VI(lLIMIT) Resolution 3 bits VILIM(MAX) Hi Range l 68 75 82 mV Lo Range l 44 50 56 mV VILIM(MIN) Hi Range 37.5 mV Lo Range 25 mV
Gate Driver (DRVCC = 9V)
TG TG Transition Time: (Note 4) tr Rise Time CLOAD = 3300pF 30 ns tf Fall Time CLOAD = 3300pF 30 ns BG BG Transition Time: (Note 4) tr Rise Time CLOAD = 3300pF 20 ns tf Fall Time CLOAD = 3300pF 20 ns TG/BG t1D Top Gate Off to Bottom Gate On Delay Time (Note 4) CLOAD = 3300pF 50 ns BG/TG t2D Bottom Gate Off to Top Gate On Delay Time (Note 4) CLOAD = 3300pF 50 ns tON(MIN) Minimum On-Time 45 ns Rev. 0 For more information www.analog.com 5 Document Outline Table of Contents Features Applications Typical Application Description Table of Contents Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Overview Main Control Loop EEPROM CRC Protection Power-Up and Initialization Soft-Start Time-Based Sequencing Event-Based Sequencing Shutdown Light-Load Current Operation PWM Loop Compensation Switching Frequency and Phase Output Voltage Sensing Output Current Sensing Input Current Sensing PolyPhase Load Sharing External/Internal Temperature Sense RCONFIG (Resistor Configuration) Pins Fault Handling Status Registers and ALERT Masking Mapping Faults to FAULT Pins Power Good Pins 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 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 Optional Schottky Diode Selection CIN and COUT Selection Variable Delay Time, Soft-Start and Output Voltage Ramping Digital Servo Mode Soft Off (Sequenced Off) DRVCC Regulator Topside MOSFET Driver Supply (CB, DB) Undervoltage Lockout Fault Indications Open-Drain Pins Phase-Locked Loop and Frequency Synchronization Minimum On-Time Considerations External Temperature Sense Derating EEPROM Retention at Temperature Input Current Sense Amplifier External Resistor Configuration Pins (RCONFIG) Voltage Selection Frequency Selection Phase Selection Address Selection Using RCONFIG Efficiency Considerations Programmable Loop Compensation Checking Transient Response PolyPhase Configuration PC Board Layout Checklist PC Board Layout Debugging Design Example Additional Design Checks Connecting the USB to I2C/SMBus/PMBus Adapter to the LTC3889 In System LTpowerPlay: An Interactive GUI for Digital Power PMBus Communication and Command Processing 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 External 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 Telemetry EEPROM Memory Commands Store/Restore Fault Logging Fault Log Operation Block Memory Write/Read Typical Applications Package Description Typical Application Related Parts