In this paper a comparison of common single-phase and three-phase DC-DC resonant and non- resonant converter bridges on application level is carried out. Device stresses and efficiencies are qualified at constant transferred power and constant terminal voltages. As a result, this paper presents the predominance of three-phase topologies when talking about switching losses in silicon devices of non-resonant solutions. Subsequently transformer efficiency is discussed in detail for specific core geometries. Finally the stress on the input capacitors is qualified. Concerning losses and charge to be buffered the predominance of the three-phase topology is shown.