This book describes the development and design of a unique combined data and power management infrastructure The use in small satellites gives some particular requirements to the systems like potential hardware failure robustness and handling of different types of external analog and digital interfaces. These requirements lead to a functional merge between On Board Computer and the satellite's Power Control and Distribution Unit, which results in a very innovative design and even a patent affiliation. This book provides system engineers and university students with the technical knowledge as mix between technical brochure and a user guide.