Patent ID: 7675722
Filing Date: 2010-03-09
Classification: H02H

Abstract:
1. An electrostatic discharge protection device constructed between an external voltage line and a grounding voltage line for protecting an internal circuit of the semiconductor device from the static electricity inputted to an input/output terminal, comprising: a first transferring unit transferring the static electricity inputted to said input/output terminal to said grounding voltage line; a detecting unit that senses the potential difference between both ends of said first transferring unit, connected between an input directly connected to said input/output terminal and an output connected to said grounding voltage line, to output the detection voltage; and a discharging unit driven by said detection voltage and connecting said external voltage line and said grounding voltage line to form a discharging path for the static electricity, wherein the detecting unit is turned on from a voltage drop from the first transferring unit transferring the static electricity inputted to said input/output terminal to said grounding voltage line, wherein said detecting unit includes a NMOS transistor having a gate connected to said grounding voltage line, a source directly coupled to said input/output terminal and a resister connected between a drain of said NMOS transistor and said external voltage line.