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:
Mar. 02, 2010
Filed:
Jan. 17, 2002
Applicants:
Allan Paul T. UY, Pasadena, CA (US);
Richard Joseph Mcconnell, Rancho Cucamonga, CA (US);
Inventors:
Allan Paul T. Uy, Pasadena, CA (US);
Richard Joseph McConnell, Rancho Cucamonga, CA (US);
Assignee:
SIRF Technology, Inc., San Jose, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H02J 1/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
A method and apparatus for detecting the presence of a specified voltage source and automatically switching off a second voltage source regardless of voltage source potential of the two voltage sources are disclosed. The present invention uses pinch-off of a JFET, controlled by an inverter, to control a backup power supply based on the availability of the main supply.