Pololu 2851 5V, 5A Step-Down Voltage Regulator D24V50F5

Input voltage: 4.5 V to 38 V for the version that outputs 3.3 V Fixed 3.3 V, 5 V, 6 V, 7.5 V, or 9 V output (depending on regulator version) with 4% accuracy Typical maximum continuous output current: 2.5 A Integrated reverse-voltage protection, over-current protection, over-temperature shutoff, and soft-start Typical efficiency of 85% to 95%, depending on input voltage and load; the switching frequency automatically changes at light loads to maintain high efficiencies