The 3834-S28 from Modular Devices is a DC to DC Converter with Input Voltage 9 to 20 V, Output Voltage 1 27.7 to 28.3 V, Output Current 1 0.007 to 0.071 A, Output Power 2000 mW, Isolation Voltage 500 Vdc. Tags: Through Hole. More details for 3834-S28 can be seen below.