The AP1509 from Diodes Incorporated is a DC to DC Converter with Input Voltage 4.5 to 22 V, Output Voltage 1 1.23 to 18 V, Output Current 1 2000 mA, Operating Temperature -20 to 85 Degree C, Storage Temperature -65 to 150 Degree C. Tags: Surface Mount, Buck/Step down. More details for AP1509 can be seen below.