Technique for improving negative potential immunity of an integrated circuit

摘要

An integrated circuit (IC) with negative potential protection includes at least one double-diffused metal-oxide semiconductor (DMOS) cell formed in a first-type epitaxial pocket, which is formed in a second-type substrate. The IC also includes a second-type+ isolation ring formed in the substrate to isolate the first-type epitaxial pocket and a first-type+ ring formed through the first-type epitaxial pocket between the second-type+ isolation ring and the DMOS cell.