A packaged semiconductor chip includes features such as a chip carrier having a large thermal conductor which can be solder-bonded to a circuit panel so as to provide enhanced thermal conductivity to the circuit panel and electromagnetic shielding and a conductive enclosure which partially or completely surrounds the packaged chip to provide additional heat dissipation and shielding. The packaged unit may include both an active semiconductor chip and a passive element, desirably in the form of a chip, which includes resistors and capacitors. Inductors may be provided in whole or in part on the chip carrier.