Well resistor for ESD protection of CMOS circuits

US5654860A · kind A · utility

Assignee

• Micron Technology, Inc. · US

Inventors

• Stephen L. Casper · Boise, US
• Manny K. F. Ma · Boise, US
• Joseph C. Sher · Meridian, US

Key dates

• Filing date: Aug 16, 1995
• Grant date: Aug 5, 1997
• Expiry date: Aug 16, 2015

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D89/811

Abstract

A circuit for providing electrostatic discharge (ESD) protection is disclosed. The circuit comprises a pair of CMOS field effect pull up and pull down transistors with reduced resistance source and drain, having a well resistor formed external to them between supply and ground busses respectively. During an ESD event, the well resistors serve to both limit the current flow through the transistors, and reduce the voltage drop across them.