A package substrate includes a first metal layer, a second metal layer, isolation material containing the first and second metal layers, an isolation circuit, a first plurality of contact pads, and a second plurality of contact pads. The isolation circuit includes a first circuit element in the first metal layer and a second circuit element in the second metal layer and electrically isolated from the first circuit element by the isolation material. The first plurality of contact pads is adapted to be coupled to a first integrated circuit on the package substrate and includes a first contact pad coupled to the first circuit element. The second plurality of contact pads is adapted to be coupled to a second integrated circuit on the package substrate and includes a second contact pad coupled to the second circuit element.