This datasheet introduces LT3431, a high voltage, 3A, 500kHz step-down switching regulator. It features a wide input range (5.5V to 60V), 3A peak switch current, small thermally enhanced 16-pin TSSOP package, constant 500kHz switching frequency, saturated switch design (0.1Ω), peak switch current maintained over full duty cycle range, effective supply current 2.5mA, shutdown current 30µA, 1.2V feedback reference voltage, easily synchronized, cycle-by-cycle current limiting and more.