Patent ID: 7777999

Claim:
An electrostatic discharge (ESD) protection device formed in a substrate of first conductivity type (FCT), and comprising: an Input/Output (I/O) terminal structure comprising; a first well region of second conductivity type (SCT) formed in the substrate, a first SCT region formed in the first well region and a first FCT region formed in the first well region and spaced apart from the first SCT region, the first SCT region and the first FCT region being connected to an I/O terminal, and bridge region of SCT formed in contact with the first well region and the substrate; a current discharge structure comprising: a second SCT region formed in the substrate and separated from the bridge region by a gate electrode, a second well region of SCT region formed in the substrate below the second SCT region, a third well region of SCT formed in the substrate and separated from the second well region by a second FCT region formed in the substrate, a third SCT region, a third FCT region, and a fourth SCT region spaced apart and formed in the third well region, and a fourth FCT region formed in the substrate on a side of the third well region opposite the second FCT region.