LT3477

FEATURES n Dual 100mV Rail-to-Rail Current Sense Amplifiers n Wide Input Voltage Range: 2.5V to 25V n 3A, 42V Internal Switch n High Efficiency Power Conversion: Up to 93% n Drives LEDs in Boost, Buck-Boost or Buck Mode n Frequency Set by External Resistor: 200kHz to 3.5MHz n Programmable Soft-Start n Low VCESAT Switch: 0.3V at 2.5A n Capable of Positive and Negative Output Voltages (Boost, Inverting, SEPIC, Flyback) n Available in Thermally Enhanced 20-Lead (4mm × 4mm) QFN and 20-Lead TSSOP Packages APPLICATIONS n High Power LED Driver n DSL Modems n Distributed Power n Input/Output Current Limited Boost, SEPIC, Inverting, Flyback Converters n Constant-Voltage, Constant-Current Source LT3477 3A, DC/DC Converter with Dual Rail-to-Rail Current Sense DESCRIPTION The LT®3477 is a current mode, 3A DC/DC step-up converter with dual rail-to-rail current sense amplifiers and an internal 3A, 42V switch. It combines a traditional voltage feedback loop and two unique current feedback loops to operate as a constant-current, constant-voltage source. Both current sense voltages are set at 100mV and can be adjusted independently using the IADJ1 and IADJ2 pins. Efficiency of up to 91% can be achieved in typical applications. The LT3477 features a programmable soft-start function to limit inductor current during start-up. Both inputs of the error amplifier are available externally allowing positive and negative output voltages (boost, inverting, SEPIC, Flyback). The switching frequency is progra...