Patent · US Expired

ESD protection circuit employing channel depletion

US4835653A · kind A · utility

5Cited by
5References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 19, 1988
Grant dateMay 30, 1989
Priority date
Expiry dateJan 19, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D89/601

Abstract

An electrostatic discharge protection circuit includes a P.sup.- doped channel and an N.sup.- doped channel that form a serial path between a signal pad and a transistor. Holes are depleted from the P.sup.- doped channel in response to a negative electrostatic discharge on the input signal pad; and electrons are depleted from the N.sup.- doped channel in response to a positive electrostatic discharge on the input signal pad. When either depletion occurs, the path from the signal pad to its transistor is open circuited; and so the transistor is protected. Conversely, when no electrostatic charge exists on the signal pad, the path through the P.sup.- doped channel and the N.sup.- doped channel is highly conductive; and so signals pass between the pad and the transistor very quickly.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.