An apparatus which has a first stage with an input circuit with an inductive element (1), a second stage with a number of output circuits with loads (3, 4, 5) and a switching means (S1, S2, S3) for controlling the currents from the input circuit to the output circuits is used in order to produce a number of independent DC output voltages (V1, V2, V3) from a DC input voltage (Vin). The apparatus according to the invention can be operated in various modes.