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:
Apr. 01, 1997
Filed:
Jun. 27, 1995
Yasuhisa Higashijima, Atsugi, JP;
Masaru Takeuchi, Atsugi, JP;
Mitsumi Electric Co., Ltd., Tokyo, JP;
Abstract
A protection circuit for an electric cell comprises an overcharge detection circuit (43-1, 43-2) and an overdischarge detection circuit (44-1, 44-2) both of which are connected to a chargeable electric cell (41, 42) to detect an overcharged condition and an overdischarged condition of the electric cell (41, 42), respectively. A switch (S11, S12) is inserted in a power supply line of the chargeable electric cell (41, 42) and is turned off, when the overcharge detection circuit (43-1, 43-2) or the overdischarge detection circuit (44-1, 44-2) detects the overcharged or the overdischarged condition, thereby inhibiting a charging or a discharging operation. At least the overcharge detection circuit (43-1, 43-2) of the above-mentioned two detection circuits (43-1, 43-2, 44-1, 44-2) is connected to a timing signal producing circuit (45) for supplying a first timing signal having a first duration t1 for defining an operation timing thereof, and to a processing circuit (46) for processing an output signal of the overcharge detection circuit (43-1, 43-2) activated by the first timing signal to judge the presence or absence of an overcharged condition and for turning off the switch (S11) upon Judgement of the presence of the overcharged condition.