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:
Jan. 06, 2004
Filed:
Jan. 10, 2002
Fujitsu Limited, Kawasaki, JP;
Abstract
There is intended to provide an overvoltage-protective device capable of protecting a power system from overvoltage not destructively without using a fuse. An alarm signal from an MOS transistor Tr , a structural element of a DC/DC converter , is inputted to a switching circuit , a structural element of the AC/DC converter . In case an alarm signal keeps high-level potential without indicating overvoltage-state, the switching circuit connects a output current detecting circuit having the smaller gain G to an output voltage detecting circuit as well as a feedback circuit A, thereby to set large output-power-supply capability. In case an alarm signal inverses to low-level potential indicating overvoltage-state, the switching circuit connects a output current detecting circuit having the larger gain G to the output voltage detecting circuit as well as the feedback circuit A, thereby to set small output-power-supply capability. Thus, overvoltage at the DC/DC converter can be avoided.