Abstract: A package device has one integrated circuit in a cavity in a package substrate and electrically coupled to one side of the package substrate. A second integrated circuit is mounted on another side of the package device and electrically coupled to that side as well. A third integrated circuit or more may be mounted on the second integrated circuit. Pads useful for testing are present on both sides of the package substrate. The integrated circuits may be tested before final encapsulation to reduce the risk of providing completed packages with non-functional integrated circuits therein.