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:
Dec. 04, 2007
Filed:
May. 25, 2004
Shinobu Miyazaki, Osaka, JP;
Masaki Nakaishi, Osaka, JP;
Shinichi Masuda, Tondabayashi, JP;
Tabuchi Electric Co., Ltd., Osaka, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
At least one of a start abnormality detector (), a temperature abnormality detector () and a voltage abnormality detector () has a latch inhibiting circuit for inhibiting retention of a detecting state when one of the abnormality detectors detects an abnormality, so that a current abnormality detector () can be inhibited from detecting an abnormal input current caused when the oscillation is halted by the abnormality detector. Accordingly, after the abnormality is removed, automatic resetting can be easily accomplished without causing the oscillation to halt as a result of the current abnormality detector detecting the presence of the abnormality. Also, since a power source abnormality detecting circuit () is designed in the form of an analog circuit, a low cost can be achieved and the monitoring level can be modified. In addition, the monitoring level associated only with the temperature abnormality occurring in an IGBT element () can be modified.