Patent ID: 6724677
Filing Date: 2004-04-20
Classification: H01L

Abstract:
An electrostatic discharge (ESD) device used with a high-voltage input pad, wherein the ESD device is disposed between the high-voltage input pad and an internal circuit, comprising:a primary device disposed on a substrate, wherein the primary device is coupled to the high-voltage input pad and the internal circuit; and a secondary device disposed on the substrate between the primary device and the internal circuit, wherein the secondary device comprising: a first MOS transistor comprising a first gate, a first drain and a first source, wherein the first gate is coupled to a bias Vg1, and the first drain is coupled to the high-voltage input pad; and a second MOS transistor comprising a second gate, a second drain and a second source, wherein the second gate and the second source are both grounded, and the second drain is electrically connected with the first source of the first MOS transistor.