Abstract: A semiconductor device package for one or more semiconductor dice uses a package substrate having one pair of biplanar conductive planes and another pair of biplanar conductive planes. The pairs of planes are positioned in a coplanar relationship between the top traces and the bottom traces. Power may be supplied to die core circuits through one pair of planes and to die input-output circuits through another pair of planes to decouple the core circuits from the input-output circuits and minimize noise induced false switching in either set of circuits. The core circuits and the input-output circuits may be powered by the same power supply or separate power supplies.