公开(公告)号：JPH1070238A

公开(公告)日：1998-03-10

申请号：JP12823497

申请日：1997-05-19

Applicant: SYMBIOS LOGIC INC

Inventor： WALKER JOHN D ,  DANIEL DAVID W

IPC: H01L27/04 ,  H01L21/822 ,  H01L27/02

Abstract: PROBLEM TO BE SOLVED: To shorten the time required for fabricating a semiconductor device while reducing the cost and the material by incorporating an electrostatic discharge protection circuit into an integrated circuit itself without increasing the labor significantly. SOLUTION: An input pad 20 is connected through resistors 21, 30 with an IN signal line 22 which is connected with another circuit on a chip. A thick field device 23 connects Vdd 26 with Vss and functions as a return path of an electrostatic discharge pulse. It is switched to an input protection device before the electrostatic discharge pulse causes any damage onto a running circuit. An SCR 28 provides an independent path 29 from the input pad 20 to the Vss. The resistors 21, 30 limit current to the IN signal line 22 and an IN signal gives the SCR 28 a chance for turning on and shunting the electrostatic discharge pulse. The resistor 21 has a resistance of 10Ω and the resistor 31 has a resistance of 150-200Ω.