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. 25, 2022
Filed:
Jul. 12, 2019
Daichi Yamashita, Tokyo, JP;
Norihito Kawaguchi, Tokyo, JP;
Yoshihiro Satake, Tokyo, JP;
Nobuhito Tanaka, Tokyo, JP;
Koji Koshimizu, Tokyo, JP;
Daichi Yamashita, Tokyo, JP;
Norihito Kawaguchi, Tokyo, JP;
Yoshihiro Satake, Tokyo, JP;
Nobuhito Tanaka, Tokyo, JP;
Koji Koshimizu, Tokyo, JP;
MITSUMI ELECTRIC CO., LTD., Tokyo, JP;
Abstract
A secondary battery protection circuit for a secondary battery includes: a reference voltage circuit configured to generate a reference voltage by using a depletion-type transistor and a transistor unit of enhancement type connected in series with the depletion-type transistor; a voltage divider configured to output a detection voltage obtained by dividing a power source voltage of the secondary battery; a detection circuit configured to detect an abnormal state of the secondary battery based on the reference voltage and the detection voltage; a first adjustment circuit configured to adjust a size ratio of the depletion-type transistor to the transistor unit based on threshold voltages of the depletion-type transistor and the transistor unit; and a second adjustment circuit configured to adjust the detection voltage based on the reference voltage after adjusting the size ratio.