A power generation circuit and process for providing electrical power and data transfer by means of a module attached to the audio port of a mobile electronic device. Power and data may be exchanged with an auxiliary device, which may be a sensor or a data processing device. A description of several possible power generation circuits is provided, as well as a description of different sensors and data processing devices which may be attached to a power generation circuit. The power generation circuit is particularly designed to provide a low interference and low voltage ripple output with high total power availability and efficiency.