The AP6503 from Diodes Incorporated is a DC to DC Converter with Input Voltage 4.75 to 23 V, Output Voltage 1 0.925 to 20 V, Output Current 1 3000 mA, Operating Temperature -40 to 85 Degree C, Storage Temperature -65 to 150 Degree C. Tags: Surface Mount, Buck/Step down. More details for AP6503 can be seen below.