Patent · US Expired

Floating gate FGPA cell with separated select device

US5773862A · kind A · utility

10Cited by
1References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 27, 1996
Grant dateJun 30, 1998
Priority date
Expiry dateAug 27, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10B69/00
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

The present invention provides for a programming portion of an FPGA cell of an integrated circuit and a process of manufacturing the programming portion. The programming portion has an EPROM transistor and a separated select transistor with the gate of the select transistor connected to the control gate of the EPROM transistor. Both transistors share a common N+ source/drain region, which is self-aligned with the gates of both transistors. With the select transistor separated from the EPROM transistor and the self-aligned common N+ region, the threshold voltage V.sub.T of the select transistor can be set precisely. This allows good control over the programming voltage for the control gate of the EPROM transistor and the time to program the floating gate of the EPROM transistor.

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