Protection of an integrated circuit with voltage variable materials

An electrical device comprising:

• an integrated circuit die having an outer periphery and a functional die area;
• a first conductive guard rail disposed on the integrated circuit die;
• a second conductive guard rail disposed on the integrated circuit die;
• a plurality of conductive input/output pads disposed on the integrated circuit die forming gaps between the input/output pads and the first and second guard rails;
• a plurality of electrical leads electrically connected to a respective one of the plurality of conductive input/output pads;
• a voltage variable material disposed on the integrated circuit die filling the gaps between the input/output pads and the first and second conductive guard rails, the voltage variable material electrically connecting the plurality of conductive input/output pads to the first and second conductive guard rails in response to an EOS transient energy;
• and
• a protective housing covering the integrated circuit die, the plurality of electrical leads extending outwardly from the protective housing.

An integrated circuit comprising:

• an electrically insulating substrate having at least one microelectronic device formed thereon;
• a conductive input/output pad formed on the substrate;
• a conductive guard rail formed on the substrate;
• a voltage variable material disposed on the substrate between the microelectronic device and the input/output pad and forming a path between the conductive input/output pad and the conductive guard rail, the voltage variable material exhibiting non-conductive behavior at normal circuit operating voltages and electrically connecting the input/output pad to the conductive guard rail when an EOS transient is introduced into the circuit.