LT8331 Low IQ Boost/SEPIC/Flyback/Inverting Converter with 0.5A, 140V Switch FEATURESDESCRIPTION n Wide Input Voltage Range: 4.5V to 100V The LT®8331 is a current mode DC/DC converter with a n Ultralow Quiescent Current and Low Ripple 140V, 0.5A switch operating from a 4.5V to 100V input. Burst Mode® Operation: IQ = 6µA With a unique single feedback pin architecture, it is capa- n 0.5A, 140V Power Switch ble of boost, SEPIC, flyback or inverting configurations. n Positive or Negative Output Voltage Programming Burst Mode operation consumes as low as 6μA quiescent with a Single Feedback Pin current to maintain high efficiency at very low output cur- n Programmable Frequency (100kHz to 500kHz) rents, while keeping typical output ripple below 20mV. n Synchronizable to an External Clock The internally-compensated current mode architecture n BIAS Pin for Higher Efficiency results in stable operation over a wide range of input and n Programmable Undervoltage Lockout (UVLO) output voltages and programmable switching frequencies n Thermally-Enhanced High Voltage MSOP Package between 100kHz to 500kHz. A SYNC/MODE pin allows n AEC-Q100 Qualified for Automotive Applications synchronization to an external clock. It can also be used to select between burst or pulse-skipping modes of opera- APPLICATIONS tion. For increased efficiency, a BIAS pin can accept a n second input to supply the INTVCC regulator. Additional Industrial and Automotive n features include frequency foldback and programmable Telecom n soft-start for controlling inductor current during start-up. Medical Diagnostic Equipment n Portable Electronics The LT8331 is available in a thermally-enhanced MSOP package with four pins removed for high voltage spacings. All registered trademarks and trademarks are the property of their respective owners. TYPICAL APPLICATION48V Output SEPIC ConverterEfficiency and Power Loss 220μH 2.2µF 100 2.0 • VIN VOUT = 48V 90 36V TO 150mA AT VIN = 36V 72V 1µF 4.7µF 80 ×2 220μH 165mA AT VIN = 48V 1M V EFFICIENCY IN SW1-2 ×4 190mA AT VIN = 72V 1.5 70 POWER LOSS (W) LT8331 • 60 EN/UVLO 1M POWER LOSS 50 1.0 SYNC/MODE FBX 40 EFFICIENCY (%) GND BIAS V 30 OUT 0.5 59k 34.8k 20 VIN = 36V RT SS INTVCC VIN = 48V 10 VIN = 72V 63.4k 0.1µF 1µF 0 0 0 50 100 150 200 8331 TA01a LOAD CURRENT (mA) 450kHz 8331 TA01b Rev. C Document Feedback For more information www.analog.com 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Electrical Characteristics Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts