A novel self-powered, isolated power management device for 48 V power systems

This paper describes a new approach to the design of an integrated power management device for 48 V distributed power systems. For best performance, the power management device must be independent of the DC-DC converters that it is managing. This presents a number of design challenges, particularly where isolation is required between primary (48 V) and secondary (logic voltages). The solution described here is self-powered from 48 V, and provides all necessary power management functions such as startup, shutdown, fault handling, etc. The final device is implemented in a BGA package and maintains full primary-secondary isolation without the need for optocouplers.