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:
Nov. 09, 2004
Filed:
May. 08, 2003
Applicant:
Inventor:
Seiji Takamatsu, Nagano, JP;
Assignee:
Seiko Epson Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02M 3/335 ;
U.S. Cl.
CPC ...
H02M 3/335 ;
Abstract
An overcurrent output protector is electrically connected to a constant-voltage switching power supply provided with a switching transistor which converts a DC voltage obtained by smoothing an AC voltage supplied from an AC power source into a cyclic pulse signal. In the overcurrent output protector, duty ratio monitor judges whether an ON duty ratio of the cyclic pulse signal is a predetermined ratio or more. A deactivator turns off the switching transistor in a case where the duty ratio monitor judges that the ON duty ratio is the predetermined ratio or more.