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:
Aug. 24, 2004
Filed:
Apr. 07, 2000
Yoshinobu Fujiwara, Kamagaya, JP;
Uniden Corporation, Tokyo, JP;
Abstract
The present invention provides an improved method of protecting a subscriber telephone interface circuit from the application of excess voltages and currents. The method uses a standard subscriber telephone interface circuit, including a speech circuit and a ringing detection circuit, in conjunction with updated controlling software. When excess voltage or current is detected by the ringing detection circuit, a CPU disconnects the speech circuit. The speech circuit is reconnected when the excess voltage or current is removed. The present invention further provides a ringing detection circuit that connects a speech circuit when a ringing signal is detected, and disconnects the speech circuit when excess voltage or current is detected.