The specification describes an integrated device for the input protection of MOS circuits. It consists of an MOS capacitor formed by the thinning of a section of the input gate dielectric, SiO.sub.2, and the thinning of an adjoining section of the gate metal, Al. An incoming pulse of static charge with high amplitude and short duration will break down the thinned dielectric of the capacitor before breaking down the relatively thick portion of the gate dielectric. Since the metal over the thin dielectric is also relatively thin, it evaporates from the vicinity of the fault by the generated Joule heat immediately following the breakdown. Thus, the breakdown is self healed and can be repeated many times without damaging the circuit.