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:
Nov. 11, 1997
Filed:
Nov. 29, 1996
Takahiro Hayashi, Yokohama, JP;
Kouichi Kunitomo, Yokohama, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A charging control circuit is disclosed which comprises: a 1st connector (17) receiving an input supply power (34); a 2nd connector (30) for supplying a charging supply power (35) to charge either of a 1st (Ni-Cd) or 2nd (Lithium ion) battery (33a, 33b) and receiving a discharging supply power (36) from the battery; a kind detection portion (15) for detecting which of the 1st and 2nd kind of battery is to be charged; a voltage detection circuit for detecting an emf of the battery to be charged; a current detection circuit for detecting a charging current to the battery to be charged; a REF signal generation portion (15) for generating a REF signal (38) in accordance with outputs from the kind detection portion, the current detection circuit, and the voltage detection circuit; a difference providing portion (111) for providing a difference between the REF signal and the detected emf; and a charging supply power generation circuit for generating the charging supply power from the input supply power according to the output of the difference providing portion (111). The Ni-Cd battery is charged by a constant current and the lithium ion battery, by a constant current and a constant voltage (4.1 V). Completion of charging is detected by a drop of emf of Ni-Cd and decrease in the charging current to Lithium ion battery.