Datasheet LTC3888-1 (Analog Devices) - 6

LTC3888-1
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the specified operating junction temperature range, otherwise specifications are at TA = 25°C (Notes 2, 8). VIN = 12V, VSENSEn + = 1V, VSENSEn – = GND = 0V, fSYNC = 500kHz (externally driven) unless otherwise specified. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS VIN Supply
VIN VIN Operating Range l 4.5 26.5 V IQ IC Operating Current RUN0,1 = 0V 24 mA RUN0,1 = 3.3V, CPWMn = 0pF 28 mA
INTVCC Linear Regulator Supply
INTVCC INTVCC Output Voltage VIN ≥ 6V (Note 4) 5.2 V EXTVCC INTVCC Input Voltage Range VIN = INTVCC (Note 4) l 4.5 5.5 V V5UVLO PWM Undervoltage VDD33 Rising l 4.45 V Lockout Threshold Hysteresis 300 mV
VDD33 Linear Regulator Supply
VDD33 VDD33 Output Voltage INTVCC ≥ 4.5V (Note 5) l 3.15 3.3 3.45 V V3UVLO PMBus Undervoltage VDD33 Rising l 3.10 V Lockout Threshold Hysteresis 275 mV
VDD25 Linear Regulator
VDD25 VDD25 Output Voltage (Note 7) 2.5 V
PWM Control Loops
VFB Regulated Feedback Voltage VOUT_SCALE_LOOP Not Programmed 400 mV IFB VFB Input Current VFB = 0.4V l –100 100 nA VOUT Accuracy without Servo (Note 10) 1V ≤ VOUT ≤ 3.45V l –1.5 1.5 % Accuracy with Servo 0.3V ≤ V ±0.2 % (Notes 9, 10, See Test Circuit) OUT ≤ 3.45V 0.3V ≤ V –0.5 0.5 % Servo Resolution OUT ≤ 3.45V l 12 Bits RVSENSE VSENSE Input Resistance l 30 43.3 kΩ VLINEREG Line Regulation 6V ≤ VIN ≤ 24V (Note 10) –0.02 0.02 %/V VLOADREG Load Regulation ΔITHn = ±600mV (Note 10) –0.1 0.1 % gm Resolution 3 Bits Error Amplifier gm(MAX) ITH = 1.35V 5.76 mmho Error Amplifier gm(MIN) 1 mmho LSB Step Size 0.68 mmho RITH Resolution (nonlinear) Compensation 5 Bits Resistance RTH(MAX) Compensation 62 kΩ Resistance RTH(MIN) 1 kΩ ISHARE_TOL Phase-to-Phase Output Current ISENSEn – IREF ≥ 150mV l –6.5 6.5 % Sharing Accuracy ±3 % IISENSE ISENSEn Input Current 1.5V ≤ ISENSEn ≤ 1.9V l –1 3 µA VIREF Current Monitor Reference Output IIREF = 3mA 1.52 1.68 V Voltage (Note 6) IIREF IREF Output Current Source, IREF ≥ 1.52V –500 µA Sink, IREF ≤ 1.68V 10 mA fSYNC SYNC Output Frequency Accuracy l –7.5 7.5 % tON(MIN) Minimum On-Time MFR_PWM_MODE_LTC3888-1[3] = 1 l 30 60 ns MFR_PWM_MODE_LTC3888-1[3] = 0 21 ns Rev. 0 6 For more information www.analog.com Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Test Circuit Operation Overview About This Document Major Product Features Main Control Loop Power-Up and Initialization Testing Integrity of Output Voltage Sense Analog Output Voltage Control PMBus Output Voltage Control Soft-Start Time-Based Output Sequencing Output Ramping Control Voltage-Based Output Sequencing Output Disable Minimum Output Disable Times Output Short Cycle Switching Frequency and Phase PolyPhase Load Sharing Voltage Control Loop Compensation Load Step Emulation Input Supply Monitoring Output Voltage Sensing and Monitoring Output Current Sensing and Monitoring Temperature Sense Resistor Configuration Pins Internal EEPROM with CRC Fault Detection Input Supply Faults Hardwired PWM Response to Power Stage Faults Hardwired PWM Response to Power Stage UV Hardwired PWM Response to VOUT Faults Power Good Indication Hardwired PWM Response to IOUT Faults Hardwired PWM Response to Internal Temperature Faults External Temperature Faults Timing Faults External Faults Higher-Level Fault Handling Status Registers and ALERT Masking FAULT Pin I/O Fault Log Operation Fault Log Details Factory Default Operation Serial Interface Serial Bus Addressing Serial Bus Timeout Serial Communication Errors PMBus Command Summary PMBus Commands Data Formats Applications Information Efficiency Considerations Power Stage Selection and Interface Using The VDR Monitor Unused TSNS Inputs PWM Frequency and Inductor Selection CIN Selection COUT Selection Programmable Loop Compensation PCB Layout Considerations Output Voltage Sensing Classical Analog Output Voltage Control PMBus Output Voltage Control Using Output Voltage Servo Soft-Start and Stop Time-Based Output Sequencing and Ramping Voltage-Based Output Sequencing PWM Frequency Synchronization PolyPhase Operation and Load Sharing Resistor Configuration Pins Internal Regulator Outputs IC Junction Temperature Derating EEPROM Retention at Temperature Configuring Open-Drain Pins PMBus Communication and Command Processing Status and Fault Log Management LTpowerPlay – An Interactive Digital Power GUI Interfacing to the DC1613 Design Example PMBus Command Details Addressing and Write Protect PAGE PAGE_PLUS_WRITE PAGE_PLUS_READ WRITE_PROTECT MFR_ADDRESS MFR_RAIL_ADDRESS General Device Configuration PMBUS_REVISION CAPABILITY MFR_CONFIG_ALL On, Off and Margin Control ON_OFF_CONFIG OPERATION MFR_RESET PWM Configuration FREQUENCY_SWITCH MFR_CHAN_CONFIG MFR_PWM_CONFIG_LTC3888-1 MFR_PWM_MODE_LTC3888-1 MFR_PWM_COMP Input Voltage and Limits VIN_ON VIN_OFF VIN_OV_FAULT_LIMIT VIN_UV_WARN_LIMIT Output Voltage and Limits VOUT_MODE VOUT_COMMAND VOUT_MAX MFR_VOUT_MAX VOUT_MARGIN_HIGH VOUT_MARGIN_LOW VOUT_SCALE_LOOP VOUT_OV_FAULT_LIMIT VOUT_OV_WARN_LIMIT VOUT_UV_WARN_LIMIT VOUT_UV_FAULT_LIMIT Output Current and Limits IOUT_CAL_GAIN MFR_LOAD_EMULATION MFR_LOAD_EMULATION IOUT_OC_FAULT_LIMIT IOUT_OC_WARN_LIMIT Output Timing, Delays, and Ramping MFR_RESTART_DELAY TON_DELAY TON_MAX_FAULT_LIMIT VOUT_TRANSITION_RATE TOFF_DELAY TOFF_MAX_WARN_LIMIT External Temperature and Limits MFR_TEMP_1_GAIN MFR_TEMP_1_OFFSET OT_FAULT_LIMIT OT_WARN_LIMIT Status Reporting STATUS_BYTE STATUS_WORD STATUS_VOUT STATUS_IOUT STATUS_INPUT STATUS_TEMPERATURE STATUS_CML STATUS_MFR_SPECIFIC MFR_PADS_LTC3888-1 MFR_COMMON MFR_INFO CLEAR_FAULTS Telemetry READ_VIN MFR_VIN_PEAK READ_VOUT MFR_VOUT_PEAK READ_IOUT MFR_IOUT_PEAK MFR_TOTAL_IOUT MFR_READ_ALL_IOUT READ_TEMPERATURE_1 MFR_TEMPERATURE_1_PEAK READ_TEMPERATURE_2 MFR_TEMPERATURE_2_PEAK READ_FREQUENCY MFR_CLEAR_PEAKS Fault Response and Communication VIN_OV_FAULT_RESPONSE VOUT_OV_FAULT_RESPONSE VOUT_UV_FAULT_RESPONSE IOUT_OC_FAULT_RESPONSE OT_FAULT_RESPONSE MFR_OT_FAULT_RESPONSE TON_MAX_FAULT_RESPONSE MFR_RETRY_DELAY SMBALERT_MASK MFR_FAULT_PROPAGATE MFR_FAULT_RESPONSE MFR_FAULT_LOG MFR_FAULT_LOG_CLEAR EEPROM User Access STORE_USER_ALL RESTORE_USER_ALL MFR_COMPARE_USER_ALL MFR_FAULT_LOG_STORE MFR_EE_xxxx USER_DATA_0x Unit Identification MFR_ID IC_DEVICE_ID MFR_SPECIAL_ID Package Description Typical Applications Related Parts