Patent · US Expired

Electrically programmable read only memory array

US5432730A · kind A · utility

103Cited by
5References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 20, 1993
Grant dateJul 11, 1995
Priority date
Expiry dateDec 20, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C16/0491
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

There is provided an EPROM array including columns of EPROM cells, three types of diffusion bit lines, two types of metal lines and two types of select transistors. The metal lines are formed of metal 1 lines and metal 2 lines, where the metal 1 lines are formed into segmented lines and continuous lines and the metal 2 lines are continuous. The diffusion bit lines are formed of short, medium and continuous lines, where the medium length diffusion lines are associated with one segmented metal 1 line and one metal 2 line, the continuous lines are associated with one continuous metal 1 line and the short bit lines are formed of short segments and are not associated with metal lines. The diffusion lines repeat in the following order: medium length, short, continuous, short. One type of select transistor connects one short diffusion line to one metal 1 line and the second type of select transistor connects one segmented metal 1 line to one metal 2 line. Each column of EPROM cells are located between two neighboring diffusion lines.

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