A device for generating locallised heating in a selected body tissue is disclosed. A main printed circuit board 10 and a sub board 17 are composite-molded, and the sub board 17 is formed at an area close to or immediately below a heat-generating electronic component 23 or a heat dissipation plate 23a. The controller includes a logic engine that provides configuration information to the dispersion compensation circuit. A fan module including at least one fan used for dissipating heat from the extension card module is provided.