LT8365 (Rev. A) - Analog Devices

1 LT83651 Rev. AFor more information FeedbackTYPICAL APPLICATION FEATURESDESCRIPTIONLow IQ Boost/SEPIC/Inverting converter with , 150V SwitchThe LT 8365 is a current mode DC/DC converter with a , 150V switch operating from a to 60V input. With a unique single feedback pin architecture it is capable of boost, SEPIC or inverting configurations. Burst Mode operation consumes as low as 9 A quiescent current to maintain high efficiency at very low output currents, while keeping typical output ripple below external compensation pin allows optimization of loop bandwidth over a wide range of input and output voltages and programmable switching frequencies between 100kHz and 500kHz. A SYNC/MODE pin allows synchronization to an external clock. It can also be used to select between burst or pulse-skipping modes of operation with or with-out spread spectrum frequency modulation for low EMI. For increased efficiency, a BIAS pin can accept a second input to supply the INTVCC regulator.

2 Additional features include frequency foldback and programmable soft-start to control inductor current during LT8365 is available in a thermally enhanced 16-lead MSOP package with four pins removed for high voltage pin , 250V Output Inverting ConverterAPPLICATIONS nWide Input Voltage Range: to 60V nUltralow Quiescent Current and Low Ripple Burst Mode Operation: IQ = 9 A , 150V Power Switch nPositive or Negative Output Voltage Programming with a Single Feedback Pin nProgrammable Frequency (100kHz to 500kHz) nSynchronizable to an External Clock nSpread Spectrum Frequency Modulation for Low EMI nBIAS Pin for Higher Efficiency nProgrammable Undervoltage Lockout (UVLO) nThermally Enhanced 16-lead MSOP Package nAEC-Q100 Qualified for Automotive Applications nIndustrial and Automotive nTelecom nMedical Diagnostic Equipment nPortable ElectronicsAll registered trademarks and trademarks are the property of their respective Waveforms1 F10 F1M F10 F20 20 FEN/UVLORTVINSWFBXBIASINTVCCSSGNDVCLT836 5 SYNC/MODEVINVOUT9V TO 30V 250V10mAD1, D2, D3, D4: DIODES INC.

3 DFLS1150L1: WURTH ELEKTRONIK WE-PD 74437324100 VOUT8365 TA01a1 s/DIVIL500mA/DIVVSW50V/DIV8365 TA01bLT83652 Rev. AFor more information ..150 VVIN, EN/UVLO ..60 VBIAS ..60 VEN/UVLO Pin Above VIN Pin, ..(Note 2)VC ..4 VFBX .. 4 VOperating Junction Temper atur e (Note 3) LT8365E .. 40 C to 125 C LT8365J, LT8365H .. 40 C to 150 CStorage Temper atur e Range .. 65 C to 150 CORDER INFORMATIONLEAD FREE FINISHTAPE AND REELPART MARKING*PACKAGE DESCRIPTIONTEMPERATURE RANGELT8365 EMSE#PBFLT8365 EMSE#TRPBF836516-Lead Plastic MSOP with 4 Pins Removed 40 C to 125 CLT8365 JMSE#PBFLT8365 JMSE#TRPBF836516-Lead Plastic MSOP with 4 Pins Removed 40 C to 150 CLT8365 HMSE#PBFLT8365 HMSE#TRPBF836516-Lead Plastic MSOP with 4 Pins Removed 40 C to 150 CAUTOMOTIVE PRODUCTS** LT8365 EMSE#WPBFLT8365 EMSE#WTRPBF836516-Lead Plastic MSOP with 4 Pins Removed 40 C to 125 CLT8365 JMSE#WPBFLT8365 JMSE#WTRPBF836516-Lead Plastic MSOP with 4 Pins Removed 40 C to 150 CLT8365 HMSE#WPBFLT8365 HMSE#WTRPBF836516-Lead Plastic MSOP with 4 Pins Removed 40 C to 150 CContact the factory for parts specified with wider operating temperature ranges.

4 *The temperature grade is identified by a label on the shipping and reel specifications. Some packages are available in 500 unit reels through designated sales channels with #TRMPBF suffix.**Versions of this part are available with controlled manufacturing to support the quality and reliability requirements of automotive applications. These models are designated with a #W suffix. Only the automotive grade products shown are available for use in automotive applications. Contact your local Analog Devices account representative for specific product ordering information and to obtain the specific Automotive Reliability reports for these 3 5678EN/UVLOVININTVCCNCBIASVC16 14 1211109SW1SW2 SYNC/MODESSRTFBXTOP VIEW17 PGND, GNDMSE PACKAGEVARIATION: MSE16 (12)16-LEAD PLASTIC MSOP JA = 45 C/W, JC = 10 C/W EXPOSED PAD (PIN 17) IS PGND AND GND, MUST BE SOLDERED TO PCBPIN CONFIGURATIONABSOLUTE MAXIMUM RATINGS(Note 1)LT83653 Rev. AFor more information Operating Voltage Quiescent Current at ShutdownVEN/UVLO = l1 12 15 A AVEN/UVLO = l2 25 25 A AVIN Quiescent CurrentSleep Mode (Not Switching)SYNC = 0V l9 915 30 A AActive Mode (Not Switching)SYNC = 0V or INTVCC, BIAS = 0V l1200 12001600 1850 A ASYNC = 0V or INTVCC, BIAS = 5V l22 2240 65 A ABIAS ThresholdRising, BIAS Can Supply INTVCC Falling, BIAS Cannot Supply VVIN Falling Threshold to Supply INTVCCBIAS = 12 VBIAS 2 VVBIAS Falling Threshold to Supply INTVCCVIN = 12 VVINVFBX RegulationFBX Regulation VoltageFBX > 0V FBX < 0Vl VFBX Line RegulationFBX > 0V, < VIN < 60V FBX < 0V, < VIN < %/VFBX Pin CurrentFBX = , 1010nAOscillatorSwitching Frequency (fOSC)RT = 432k RT = 143k RT = l l92 279 465100 300 500113 321 535kHz kHz kHzSSFM Maximum Frequency Deviation( f/fOSC) 100, RT = 143k142028%Minimum On-TimeBurst Mode, VIN = 24V (Note 6) Pulse-Skipping Mode, VIN = 24V (Note 6)

5 110 110200 200ns nsMinimum Off-Timel100115nsSYNC/Mode, Mode Thresholds (Note 5)High (Rising), VIN = 24V Low (Falling), VIN = 24Vl l VSYNC/Mode, Clock Thresholds (Note 5)Rising, VIN = 24V Falling, VIN = 24Vl l VfSYNC/fOSC Allowed RatioRT = Pin CurrentSYNC = 2V SYNC = 0V, Current Out of Pin10 1025 25 A ASwitchMaximum Switch Current Limit Overcurrent ThresholdDischarges SS Pin3 ASwitch RDS(ON)ISW = Switch Leakage CurrentVSW = AELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25 C. VIN = 12V, EN/UVLO = 12V unless otherwise AFor more information CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25 C. VIN = 12V, EN/UVLO = 12V unless otherwise 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and 2: INTVCC cannot be externally driven.

6 No additional components or loading is allowed on this 3: The LT8365E is guaranteed to meet performance specifications from 0 C to 125 C junction temperature. Specifications over the 40 C to 125 C operating junction temperature range are assured by design, characterization and correlation with statistical process controls. The LT8365J and the LT8365H are guaranteed over the full 40 C to 150 C operating junction temperature 4: The IC includes overtemperature protection that is intended to protect the device during overload conditions. Junction temperature will exceed 150 C when overtemperature protection is active. Continuous operation above the specified maximum operating junction temperature will reduce 5: For SYNC/MODE inputs required to select modes of operation see the Pin Functions and Applications Information 6: The IC is tested in a Boost converter configuration with the output voltage programmed for LogicEN/UVLO Pin Threshold (Rising)Start Pin Threshold (Falling)Stop Pin CurrentVEN/UVLO = 5050nASoft-StartSoft-Start Charge CurrentSS = ASoft-Start Pull-Down ResistanceFault Condition, SS = Error AmplifierError Amplifier TransconductanceFBX = FBX = 60 A/V A/VError Amplifier Voltage GainFBX = FBX = 145V/V V/VError Amplifier Max Source CurrentVC = , Current Out of Pin7 AError Amplifier Max Sink CurrentVC = ALT83655 Rev.

7 AFor more information PERFORMANCE CHARACTERISTICSS witching Frequency vs TemperatureSwitching Frequency vs VINN ormalized Switching Frequency vs FBX VoltageFBX Positive Regulation Voltagevs TemperatureFBX Negative Regulation Voltage vs TemperatureEN/UVLO Pin Thresholds vs TemperatureJUNCTION TEMPERATURE ( C) 50 VOLTAGE (V)8365 G01 VIN = 12 VJUNCTION TEMPERATURE ( C) 50 250255075100125150175 VOLTAGE (V)8365 G02 VIN = 12 VEN/UVLO RISING (TURN ON)EN/UVLO FALLING (TURN OFF)JUNCTION TEMPERATURE ( C) 50 PIN VOLTAGE (V)8365 G03 VOLTAGE (V) SWITCHING FREQUENCY (%)8365 G06 VIN = 12 VSwitch Current Limit vs Duty CycleSwitch Minimum On-Time vs TemperatureSwitch Minimum Off-Time vs TemperatureDUTY CYCLE (%) CURRENT LIMIT (A)vs Duty CycleSwitch Current Limit8365 G07 JUNCTION TEMPERATURE ( C) 50 2502550751001251501750102030405060708090 100110120130 MINIMUM OFF TIME (ns)vs TemperatureSwitch Minimum Off Time8365 G09 JUNCTION TEMPERATURE ( C) 50 2502550751001251501753803843883923964004 04408412416420 SWITCHING FREQUENCY (kHz)8365 G04 VIN (V)0510152025303540455055603803843883923 96400404408412416420 SWITCHING FREQUENCY (kHz)8365 G05 JUNCTION TEMPERATURE ( C) 50 2502550751001251501755060708090100110120 130140150 MINIMUM ON TIME (ns)8365 G08LT83656 Rev.

8 AFor more information PERFORMANCE CHARACTERISTICSS witching Waveforms(in DCM)VIN Pin Current (Sleep Mode, Not Switching) vs TemperatureVIN Pin Current (Active Mode, Not Switching, Bias = 0V) vs TemperatureVIN Pin Current (Active Mode, Not Switching, Bias = 5V) vs TemperatureVIN = 12 VVBIAS = 0 VVSYNC_MODE = 0 VJUNCTION TEMPERATURE ( C) 50 250255075100125150175036912151821242730 VIN PIN CURRENT ( A)Switching) vs TemperatureVIN Pin Current (Sleep Mode, Not8365 G10 VIN = 12V VBIAS = 0V VSYNC_MODE = FLOATJUNCTION TEMPERATURE ( C) 50 PIN CURRENT (mA)8365 G11 VIN = 12V VBIAS = 5V VSYNC_MODE = FLOATJUNCTION TEMPERATURE ( C) 50 2502550751001251501751014182226303438424 650 VIN PIN CURRENT ( A)8365 G121 s/DIVIL500mA/DIVVSW50V/DIV8365 G13LT83657 Rev. AFor more information FUNCTIONSEN/UVLO: Shutdown and Undervoltage Detect Pin. The LT8365 is shut down when this pin is low and active when this pin is high. Below an accurate threshold, the part enters undervoltage lockout and stops switching.

9 This allows an undervoltage lockout (UVLO) threshold to be programmed for system input voltage by resistively dividing down system input voltage to the EN/UVLO pin. An 80mV pin hysteresis ensures part switching resumes when the pin exceeds EN/UVLO pin voltage below reduces VIN current below 1 A. If shutdown and UVLO features are not required, the pin can be tied directly to system : Input Supply. This pin must be locally bypassed. Be sure to place the positive terminal of the input capacitor as close as possible to the VIN pin, and the negative terminal as close as possible to the exposed pad PGND copper (near EN/UVLO).INTVCC: Regulated Supply for Internal Loads. The INTVCC pin must be bypassed with a 1 F low ESR ceramic capacitor to GND. No additional components or loading is allowed on this pin. INTVCC draws power from the BIAS pin if BIAS VIN, otherwise INTVCC is powered by the VIN : No Internal Connection.

10 Leave this pin : Second Input Supply for Powering INTVCC. Removes the majority of INTVCC current from the VIN pin to improve efficiency when BIAS VIN. If unused, tie the pin to : Error Amplifier Output Pin. Tie external compensation network to this : Voltage Regulation Feedback Pin for Positive or Nega-tive Outputs. Connect this pin to a resistor divider between the output and the exposed pad GND copper (near FBX). FBX reduces the switching frequency during start-up and fault conditions when FBX is close to : A resistor from this pin to the exposed pad GND cop-per (near FBX) programs switching : Soft-Start Pin. Connect a capacitor from this pin to GND copper (near FBX) to control the ramp rate of inductor current during converter start-up. SS pin charging current is 2 A. An internal 220 MOSFET discharges this pin during shutdown or fault : This pin allows five selectable modes for optimization of performance. SYNC/MODE PIN INPUTCAPABLE MODE(S) OF OPERATION(1) GND or < (2) External ClockPulse-Skipping/Sync(3) 100k Resistor to GNDB urst/SSFM(4) Float (Pin Open)Pulse-Skipping(5) INTVCC or > the selectable modes of operation are:Burst = low IQ, low output ripple operation at light loads Pulse-skipping = skipped pulse(s) at light load (aligned to clock) Sync = switching frequency synchronized to external clock SSFM = Spread Spectrum Frequency Modulation for low , SW2 (SW): Output of the Internal Power Switch.