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:
Mar. 15, 2011
Filed:
Mar. 12, 2008
Christopher James Speyer, Spicewood, TX (US);
Christopher James Speyer, Spicewood, TX (US);
Zarlink Semiconductor (US) Inc., Austin, TX (US);
Abstract
The present invention provides a protection circuit coupled to a tip lead and a ring lead in a subscriber line interface circuit formed on a silicon substrate. The protection circuit includes first and second diodes formed on the silicon substrate and coupled to the tip lead and the ring lead, respectively. The first and second diodes are configured to provide a path from the tip lead or the ring lead to ground in response to a positive voltage at the tip lead or the ring lead. The protection circuit also includes a silicon-controlled rectifier formed on the silicon substrate and configured to provide, in response to a negative voltage at the tip lead or the ring lead, a path from the tip lead or the ring lead to ground via the silicon-controlled rectifier.