The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 30, 1998
Filed:
Aug. 27, 1996
Jack Zezhong Peng, San Jose, CA (US);
Robert M Salter, III, Saratoga, CA (US);
Robert J Lipp, Los Gatos, CA (US);
Zycad Corporation, Fremont, CA (US);
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.