Design of an energy harvesting conditioning unit for hearing aids

There is an increasing demand for giving energetic autonomy to portable and autonomous biomedical devices used not only by patients but common people who need to use the aforementioned devices. For instance, hearing aids, in order to be used for long time, must be connected to re-chargeable batteries in order to help people in case of lack of permanent electric sources. In particular, for audio-prosthesis, it is very interesting to extract electric energy from temperature or articulation movements. This paper presents some criteria of designing a conditioning and re-charging unit in order to convert human basal warmth to electric energy for audio-prosthesis; the system is based on PIC microcontroller that allows the managing of two temperatures: internal and external.