Abstract: This paper presents a chip internal second electrostatic discharge （ESD） protection clamp circuit between power and ground,it aimed to overcome the ESD trailing pulse destruction to the tiny devices,it relates to advanced process semiconductor ESD protection. New ESD clamp circuit design which consist of the advantage of filter detection circuit,using dynamic RC circuits to detect the ESD pulse,in order to trigger gate-coupled circuit turn-on uniformly,and the hysteresis design using feedback p-channel transistor to turn-off the ESD clamp quickly when ESD dissipating. For comparisons,New ESD clamp smart circuit decrease the area of resistor eightfold than normal ESD clamp circuits,extraordinary saving the ESD protection module area.