In a connection system for electronic components (1) comprising a plurality of insulating layers (2) and conductive layers (3) and further comprising at least one embedded electronic component (4) embedded within at least one of the plurality of insulating layers (2) and conductive layers (3) the at least one embedded electronic component (4) is at least one first transistor having a bulk terminal thereof in thermal contact with a thermal duct (6) comprised of a plurality of vias (7) reaching through at least one of an insulating layer (2) and a conductive layer (3) of the connection system for electronic components (1) and emerging on a first outer surface (8) of the connection system for electronic components (1) under a first surface-mounted component (10).