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:
Feb. 23, 2016
Filed:
Dec. 23, 2014
Semiconductor Energy Laboratory Co., Ltd., Atsugi-shi, Kanagawa-ken, JP;
Kei Takahashi, Kanagawa, JP;
Yoshiaki Ito, Kanagawa, JP;
Hiroki Inoue, Kanagawa, JP;
Tatsuji Nishijima, Kanagawa, JP;
Semiconductor Energy Laboratory Co., Ltd., Kanagawa-ken, JP;
Abstract
A DC converter circuit having high reliability is provided. The DC converter circuit includes: an inductor configured to generate electromotive force in accordance with a change in flowing current; a transistor including a gate, a source, and a drain, which is configured to control generation of the electromotive force in the inductor by being on or off; a rectifier in a conducting state when the transistor is off; and a control circuit configured to control on and off of the transistor. The transistor includes an oxide semiconductor layer whose hydrogen concentration is less than or equal to 5×10atoms/cmas a channel formation layer.