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:
Oct. 26, 2004
Filed:
Jul. 26, 2002
Applicant:
Inventor:
Khusrow Kiani, Oakland, CA (US);
Assignee:
National Semiconductor Corp., Santa Clara, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G05F 1/10 ;
U.S. Cl.
CPC ...
G05F 1/10 ;
Abstract
In a high tolerance I/O interface with over-voltage protection during 5V tolerant mode and back-drive mode, includes pass gate circuitry to isolate the output of the driver circuit and input of the receiver circuit from the pad voltage during stress mode. The gate voltage of the PMOS transistor of the pass gate is charged up to avoid gate oxide breakdown during stress mode. Also, the gate and well of the driver pull-up transistor are charged to NG1 to avoid current flow through the transistor and to its well.