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:
Jul. 04, 2006
Filed:
Jul. 26, 2002
Khusrow Kiani, Oakland, CA (US);
Khusrow Kiani, Oakland, CA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
In a high tolerance I/O interface with over-voltage protection beyond 5 V, a cascoded driver with PMOS pull-up and NMOS pull-down transistors, connected to a pad, is provided. Circuitry is included to maintain the floating well voltages of the PMOS pull-up driver transistors at substantially the same voltages as their respective drains, and their gate voltages at substantially the same voltages as their respective drains, under back-drive and 5 V tolerant mode. Circuitry is also provided to increase the gate voltage of one of a cascoded pair of NMOS pull-down driver transistors, so that the drain-source junction voltage and gate oxide voltage of the transistor will be less than the breakdown voltage under back-drive and 5 V tolerant mode.