The Buck-Boost DC-DC Converter is a DC-DC Converter for charging a 12V or 24V service battery in vehicles with a smart alternator . Since, when the engine is running, these dynamos (powered by the on-board electronics of Euro 5 and 6 engines) do not always emit the correct charging current, a DC-DC converter is essential for charging the service battery properly. The converter will charge the auxiliary battery with a pre-set charge voltage, eliminating high voltages (e.g. Mercedes: 15,4V) and low voltages. There is an Engine running detection system built in ensuring deep discharge of the vehicle's starting battery is avoided. Instead of this detection system, the converter can also be activated by means of a programmable input (D+, CAN bus or (+)15 connection). and can be fully programmed by means of a simple and user-friendly PC application. (USB type A male to USB type B male cable needed) . The converter can be programmed to charge a 12 V or a 24 V auxiliary battery from either a 12V or a 24V alternator and starter battery.