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. 07, 2000
Filed:
Mar. 11, 1998
Applicant:
Inventors:
Kenichi Maruyama, Yokohama, JP;
Masami Nashirozawa, Yokohama, JP;
Assignee:
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04M / ;
U.S. Cl.
CPC ...
379413 ; 379324 ; 379322 ; 379231 ; 379323 ; 361119 ;
Abstract
A telephone-system interface circuit connected to a central office via a tip line and a ring line includes a battery having a first terminal and a second terminal. A first current control circuit is connected between the tip line and the first terminal of the battery. A second current control circuit is connected between the ring line and the second terminal of the battery. The first current control circuit and the second current control circuit are equal in structure.