Abstract: Electronic package with an electronic component mounted upon a PCB or ceramic substrate by first level interconnects and housing second level interconnects on the other side of the PCB. The component is protected by an EMI shield which is grounded to a ground plane of the PCB. Especially significant when there are a plurality of components protected by the shield and when at least one of the components is an integrated circuit component (I.C.C.). The package is thus prebuilt with the EMI shield and without a separate package required for each I.C.C., and is robust in construction for shipping. The shield and ground plane provide a Faraday cage which is especially complete when the shield extends around edges of the PCB and onto its other side. The package is ready for connection to a motherboard by use of the second level interconnects and process steps to place EMI shields individually onto mother boards are avoided.

Abstract: Electronic unit in which a printed circuit board is located within a housing which includes a heat sink. The board is normally urged out of heat conductive relationship with the heat sink. As temperature increases the circuit board and heat sink are caused to move relatively so as to bring the board into heat conductive relationship with the heat sink so as to remove heat from the board. As temperature decreases the board and heat sink are again moved out of heat conductive relationship. Preferably a heat conduction element is provided to conduct heat from the board. This comprises at least one compressible member, e.g. compressible cellular material, which is progressively compressed as temperature increases. Preferably the heat conductive efficiency of the compressible member increases as compression increases.