The 3699-S28 from Modular Devices is a DC to DC Converter with Input Voltage 6 to 17 V, Output Voltage 1 27.8 to 28.2 V, Output Current 1 0.714 A, Output Power 20000 mW, Isolation Voltage 100 to 500 Vdc. Tags: Through Hole, Module. More details for 3699-S28 can be seen below.