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. 08, 2003
Filed:
Mar. 29, 2002
Yasuhiro Isomichi, Kakegawa, JP;
Hiroyuki Oku, Yokohama, JP;
Matsushita Electric Industiral Co., Ltd., Osaka, JP;
Abstract
In a cellular phone of the invention, a rechargeable battery is used as a power supply to feed power to a second load and a regulator via a charging current detector circuit and a charging switch when an external power is not fed. The power is converted to an optimum voltage by the regulator and fed to a CPU and a load. When the external power is fed, the rechargeable battery is recharged and the charging current is detected by the charging current detector circuit. While a variation in the load is caused by a change in the operating state of the cellular phone from the call termination ready state to conversation state, or while a variation in the second load is caused by lighting of a key backlight, the current flowing in the charging current detector circuit stays constant and the correct charging current can be detected exclusively.