Electro spark detector (ESD) circuit protection structure

Abstract

The invention discloses an electro spark detector (ESD) circuit protection structure which comprises an ESD signal judgment circuit, a signal selection circuit, a drive N-channel metal oxide semiconductor (NMOS) and an ESD NMOS. Port one of the ESD signal judgment circuit is connected with a power supply. Port two of the ESD signal judgment circuit is connected with the signal selection circuit. Port three of the ESD signal judgment circuit is connected with the input / output (IO) end and capable of detecting and judging whether the IO end has ESD accidents and sending judgment signal to the signal selection circuit. Port one and port two of the signal selection circuit are respectively connected with the port two of the ESD signal judgment circuit and control signals of an internal circuit. Port three of the signal selection circuit outputs signals to a grid electrode of the drive NMOS and is capable of selecting output signals and judging whether the IO end has the ESD accidents. The output signal of the port three of the signal selection circuit is low level. When the IO end has no ESD accidents after judgment, the output signal is the control signal of the inner circuit. A drain electrode of the drive NMOS is connected with the IO end. A source electrode of the drive NMOS is connected with the ground. A grid electrode of the ESD NMOS is connected with the ground through a resistor. A drain electrode of the ESD NMOS is connected with the IO end and a source electrode of the ESD NMOS is connected with the ground. The ESD circuit protection structure can solve the problem that an IO ESD protection circuit in the prior art can not protect the circuit under the state that the drive NMOS is communicated.

Description

technical field [0001] The invention relates to the field of integrated circuit manufacturing, in particular to an ESD circuit protection structure. Background technique [0002] Static electricity is an objective natural phenomenon, which can be produced in many ways, such as contact, friction, induction between electrical appliances, etc. Static electricity is characterized by long-term accumulation, high voltage, low power, small current and short action time. Static electricity causes serious harm in many fields. Friction electrification and human body static electricity are two major hazards in the electronics industry, which often cause unstable operation or even damage of electronic and electrical products. ESD is a discipline formed since the middle of the 20th century to study the generation, harm and protection of static electricity. It is customary in the world to refer to the equipment used for electrostatic protection as ESD. [0003] At present, ESD protecti...

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Problems solved by technology

[0004] The technical problem to be solved by the present invention is the problem that the existing IO ESD protection circuit cannot effectively protect the circuit when driving the NMOS on-state

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