The 171010550 from Wurth Elektronik is a DC to DC Converter with Input Voltage 2.5 to 5.5 V, Output Voltage 1 0.8 to 5.5 V, Output Current 1 1.2 A, Operating Temperature -40 to 85 Degree C, Storage Temperature -40 to 125 Degree C. Tags: Surface Mount, Buck/Step down. More details for 171010550 can be seen below.