Electrostatic discharge protection circuit

Abstract

An electro-static discharge protection circuit including a first-LDNMOS transistor, a second-LDNMOS transistor, a first-resistor, and a gate-driven resistance is provided. The drain of the first-LDNMOS transistor is served as an electro-static input end, the P-body and source of the first-LDNMOS transistor are connected to each other. A coupling-voltage signal determines whether the first-LDNMOS transistor is turned on or not. The drain, P-body, and gate of the second-LDNMOS transistor are respectively connected to the drain of the first-LDNMOS transistor, the source of the first-LDNMOS transistor, and a common-ground potential. The first-resistor is connected between the source of the first-LDNMOS transistor and the common-ground potential. One end of the gate-driven resistance is connected to the common-ground potential, the other end of the gate-driven resistance is connected to the source of the second-LDNMOS transistor to generate the coupling-voltage signal, and the coupling-voltage signal is coupled to the gate of the first-LDNMOS transistor.

Dependencies are inferred from the claim text.