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:
Oct. 28, 2008
Filed:
Jun. 07, 2005
Shoji Ichimasa, Chigasaki, JP;
Shoji Ichimasa, Chigasaki, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
The present invention provides a flash discharging circuit for simplifying the charging of electric power in a capacitor. When energy discharged from a transformer for storing and discharging energy is charged in a main capacitor of the circuit, a detection voltage inputted to a first input terminal of a comparator so as to detect a primary current flowing through a primary winding of the transformer is compared with a reference voltage inputted to a second input terminal of the comparator. According to a result of the comparison, it is detected that a predetermined primary current flows through the primary winding of the transformer. When the primary current flowing through the primary winding of the transformer is turned off, the reference voltage is set to be lower than the detection voltage.