NOVELTY - The supply has interlaced conversion cells (BCi), where each cell has a splitting switch (S) i.e. insulated gate bipolar transistor, receiving a switching control at closed and open states, for respectively closing and opening a conduction path between a node (A) and a common terminal (B3) of the cell, to permit an energy storing phase in inductors (L1, L2), and an energy transfer phase. Energy is transferred towards an output capacitor (Cs), during the transfer phase. The switch is placed between the node and the terminal (B3) in a resonant circuit (10).    USE - Non-isolated split direct current-direct current power supply e.g. boost, buck or cuk and/or buck-boost type power supply such as boost, buck or cuk and/or buck-boost type converter or voltage selector, for supplying direct current voltage to a load i.e. battery, of a portable device i.e. telephone, from direct current voltage provided by a fuel cell of a charge supplying system (all claimed), in an electric motor vehicle. Can also be used for a single ended primary inductor converter.    ADVANTAGE - The configuration of the power supply permits the reducing of switching loss of the splitting and auxiliary switches in the conversion cell, and permits the increasing of conversion efficiency of the conversion cell. The configuration of the power supply permits the reducing of loss in diodes due to small constraints in blocking speed and permits the reducing of conducted and radiated electromagnetic disturbances. The switch is placed between the node and the terminal in the resonant circuit, thus reducing the ripple at the input and the output of the power supply and enhancing the yield of the power supply. The configuration of the switch assures the reliability of the power supply, while reducing the cost of components of the power supply.    DESCRIPTION OF DRAWING(S) - The drawing shows a circuit diagram of a boost cell comprising a resonant circuit associated to a splitting switch.    Node (A)    Interlaced conversion cells (BCi)    Output terminal (B2)    Common terminal (B3)    Output capacitor (Cs)    Inductors (L1, L2)    Splitting switch (S)    Resonant circuit (10)