A circuitboard assembly in which power carrying circuitboard traces between MOSFETs or the like and edge terminals are replaced with metal leadframe structures which also serve to perform a heat dissipation function. Each of the leadframes comprises a first planar portion which is bonded by a thermally conductive epoxy to the top surface of a MOSFET and a second elevated planar portion which extends parallel to but above the circuitboard surface into contact with an edge-mounted terminal header. The leadframes may be provided with support legs as well as additional heat dissipating fins.