LT3957 Datasheet | Linear Technology

Features n Wide Input Voltage Range: 3V to 40V n Single Feedback Pin for Positive or Negative Output Voltage n Internal 5A/40V Power Switch n Current Mode Control Provides Excellent Transient Response n Programmable Operating Frequency (100k Hz to 1MHz) with One External Resistor n Synchronizable to an External Clock n Low Shutdown Current < 1μA n Internal 5.2V Low Dropout Voltage Regulator n Programmable Input Undervoltage Lockout with Hysteresis n Programmable Soft-Start n Thermally Enhanced QFN (5mm × 6mm) Package APPLICATIONS n Automotive n Tele n Industrial Boost, Flyback, SEPIC and Inverting Converter with 5A, 40V Switch DESCRIPTION The LT®3957 is a wide input range, current mode DC/DC converter which is capable of generating either positive or negative output voltages. It can be configured as either a boost, flyback, SEPIC or inverting converter. It Features an internal low side N-channel power MOSFET rated for 40V at 5A and driven from an internal regulated 5.2V supply. The fixed frequency, current-mode architecture results in stable operation over a wide range of supply and output voltages. The operating frequency of LT3957 can be set with an external resistor over a 100k Hz to 1MHz range, and can be synchronized to an external clock using the SYNC pin. A minimum operating supply voltage of 3V, and a low shutdown quiescent current of less than 1μA, make the LT3957 ideally suited for battery-powered systems. The LT3957 Features soft-start and frequency foldback functions to limit inductor current during start-up. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and No RSENSE and Thin SOT are trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Patents pending. TYPICAL APPLICATION VIN 4.5V TO 16V High Efficiency Output Boost Converter 10μH 10μF 200k EN/UVLO 95.3k SGND SENSE1 SYNC SENSE2 FBX RT SS VC INTVCC 41.2k 300k Hz 0.33μF...