The TRN 1-1221SM from Traco Power is a DC to DC Converter with Input Voltage 9 to 18 V, Output Voltage 1 5 V, Output Current 1 0.1 A, Output Power 1 W, Output Voltage 2 -5 V. Tags: Surface Mount, Buck/Step down. More details for TRN 1-1221SM can be seen below.