My research activities have been continually at the crossroads of the component, the circuit and the system, with a field of application that is always foreseen in biomedical engineering. These contributions relate to theoretical aspects, modelling/simulation, as well as experiments and characterizations. Fundamental issues related to noise and signal integrity have been continuously at the heart of this research, either on architectural aspects (linked to sensors and associated measurement systems with its analog front-end) or on more heterogeneous systems, combining software and hardware. This research report, for obtaining the authorization to conduct research, presents in a concise manner the synthesis of my career, all the studies and reflections carried out since 2001, within different institutions. It also aims to describe my research strategy, the motivations that led to certain positions and the orientations that I envisage for the future. The common thread of my works can be summarized under the following title: « From component to heterogeneous system in constrained environment: Contribution to the realization and the modelling of robust embedded devices ».