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.

Date of Patent:
Aug. 17, 2004

Filed:

Mar. 14, 2000
Applicant:
Inventors:

Tim Urry Price, Salt Lake City, UT (US);

Scott W. Rupp, Grantsville, UT (US);

Randy Rollins, West Jordan, UT (US);

Assignee:

3Com Corporation, Santa Clara, CA (US);

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04M 1/00 ; H02H 1/00 ;
U.S. Cl.
CPC ...
H04M 1/00 ; H02H 1/00 ;
Abstract

A novel line-current protection circuit for detecting excessive line current from a telephone line and protecting line interface circuitry from the excessive line current is presented. The protection circuit is adapted to detect when an excessive current is present on the tip and ring lines indicative of the misconnection of the modem or other line interface device with a telephone network that presents an incompatible interface standard. The preferred embodiment appreciates the multimode hold current specifications throughout the world and evaluates the connection of the line interface circuit with a telephone line to determine the compatibility therewith. When excessive line current is detected, the line-protection circuit switches the vulnerable line interface out of the circuit. When compatible line current levels are detected, the present invention reconfigures the configurable hold circuit into its original operating (e.g., non-testing) state for call processing.


Find Patent Forward Citations

Loading…