Abstract : This thesis deals with design, integration and implementation of an isolated micro-converter. From a theoretical study based on simplified models, pre-designs of active and passive parts have been led to target our needs. A first phase of our work was to design the active parts. These integrated active structures in 0.35 μm CMOS technology consist in the power circuit, a single-phase inverter composed of two power switching cells driven with the help of optimized drivers and a digital command for the management of an interleaved command for the purposes of a project related to networks of micro-converters. The second phase of this work consisted in the design and realization of passive magnetic components such as the HF transformer and output inductor. The studies of these components have been focused on planar structures, based on a technology kapton with copper or copper on silicon, both of them with magnetic core. The last aspect presented in this thesis concerns the techniques used to manufacture these passive components and to allow hybridization of the entire micro-converter. This study allows to address the difficulties related to such devices.