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. 07, 1989
Filed:
Mar. 03, 1988
Applicant:
Inventors:
Alexander S Keir, Chelmsford, MA (US);
John C Berry, Haverhill, MA (US);
Assignee:
Digital Equipment Corporation, Maynard, MA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02M / ;
U.S. Cl.
CPC ...
363 60 ; 363 50 ; 307110 ;
Abstract
A circuit for extending the operation of an electrical load after interruption of its power source. The circuit includes bulk capacitors charged by the power source and regulated to a predetermined voltage near their peak-voltage rating. The bulk capacitors are isolated from the power source capacitors during normal power source operation. When the power source is interrupted, the bulk capacitors are used to hold-up the load. The circuit obtains maximum hold-up time for a given physical bulk capacitor size, while also providing a consistent hold-up time over a range of power source voltages.