US Patent 7440247 Gate coupling electrostatic discharge protection circuit with redundant structures

A gate coupling electrostatic discharge protection circuit is disclosed. The protection circuit that is connected an ESD structure with gate coupling to a first level circuit and other ESD structures with gate coupling to a derived circuit derived from the first level circuit in parallel could be used to drain the electrostatic discharge. The resistance of the first level circuit and the resistance of derived circuit are matched in draining the electrostatic discharge, whereby the current wouldn't concentrate on a certain portion of these cascades structures.