Patent · US Expired

CMOS Input and output protection circuit

US4476476A · kind A · utility

25Cited by
3References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 1, 1981
Grant dateOct 9, 1984
Priority date
Expiry dateApr 1, 2001

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D84/854

Abstract

A CMOS gate protection diode clamping the input terminal to substrate potential is prevented from injecting carriers into the substrate and causing SCR latchup by forming the diode as a well to substrate junction, surrounded by another, reverse-biased, well, to both reduce injection and collect parasitic injected carriers before they can diffuse to cause latchup.

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