High-voltage tolerance input buffer and ESD protection circuit

摘要

A high-voltage tolerance input buffer and a high-voltage ESD protection circuit connected to a pad of an integrated circuit for preventing rapid gate oxide aging. The high-voltage tolerance input buffer of the present invention comprises a voltage-sharing circuit and a switch circuit, wherein the voltage-sharing circuit is connected between the pad and a power rail and generates a reference voltage not higher than the voltage of the pad. The switch circuit is connected to the voltage-sharing circuit and comprises a control gate to control the switching operation of the switch circuit according to the reference voltage. The present invention can be implemented to solve the rapid gate oxide aging problem without incurring any change in the original process flow by employing a voltage-sharing circuit.