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:
Aug. 05, 1997
Filed:
Oct. 31, 1994
Applicant:
Inventors:
Brian C Martin, Los Almos, NM (US);
Alma Anderson, Rio Rancho, NM (US);
Harold G Hanson, Albuquerque, NM (US);
Assignee:
North American Philips Corporation, New York, NY (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H02H / ;
U.S. Cl.
CPC ...
361 56 ; 361 91 ; 327309 ;
Abstract
Output overvoltage protection circuitry for circuits operating at low voltages (e.g., 3 v) interfacing to a higher voltage operating circuit (e.g., 5 v bus). To prevent problems with a pull-up PMOS device at the output when the bus is pulled-up to the higher voltage, a voltage node is provided in the circuit which follows the output voltage or the low supply voltage, whichever is higher, and a sub-circuit is provided to generate logic signals indicating when the bus is pulled too high. The PMOS device is then shut-down to prevent damage to the circuit.