Low input capacitance electrostatic discharge protection circuit utilizing feedback

US6704180B2 · kind B2 · utility

Assignee

• Medtronic, Inc. · US

Inventors

• Larry E. Tyler · Mesa, US
• James May · Tempe, US

Key dates

• Filing date: Apr 25, 2002
• Grant date: Mar 9, 2004
• Expiry date: Sep 18, 2022

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L2924/0002

Abstract

An ESD protection circuit protects circuitry internal to an integrated circuit from ESD damage to electrostatic discharge voltages occurring at one or more of the inputs of the integrated circuit while maintaining substantially zero effective capacitance at the inputs. The ESD protection circuit includes a pair of diodes of opposite conductivity coupled between at least one of the inputs of the integrated circuit and an internal node thereof for providing current paths to the operating supply rails when ESD voltages occurring at the input forward bias the diodes. A unity gain amplifier provides feedback between the input and the internal circuit node to maintain a zero voltage difference therebetween whereby the effective capacitance seen at the input is reduced to substantially zero.