A magnetic device assembly is provided for maximizing the size of the magnetic components for a predetermined power converter module by co-locating and sharing input, output, and auxiliary terminals between the substrates for the power converter and the magnetic components. Wherein complete power module is the result of constructing the separate constituent parts which include an integrated magnetic substrate, magnetic elements mounted therein, a power converter substrate, associated incorporated components located top and bottom on the power converter substrate, a composite mechanical footprint as defined by the mechanical extents of the integrated magnetic substrate and power converter substrate, and a composite electrical pinout as defined by the input-output pins which are coincident to and co-located as those of the integrated magnetic and power converter substrates.