LT3957A

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 (100kHz 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 Telecom n Industrial LT3957A Boost, Flyback, SEPIC and Inverting Converter with 5A, 40V Switch DESCRIPTION The LT®3957A 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 LT3957A can be set with an external resistor over a 100kHz 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 LT3957A ideally suited for battery-powered systems. The LT3957A features soft-start and frequency f...