A Variable VH Combined Power Clamp for System Level ESD/Surge Immunity Enhancement with Low Leakage

An on-chip power clamp which combined RC and static trigger circuits for the system level ESD/EFT/Surge enhancement is proposed. The proposed clamp can achieve the higher immunity against longer pulses such as the surge event compared to the conventional combined clamp without increasing the leakage current of the trigger circuit using a variable holding voltage technique.