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:
May. 19, 2009
Filed:
Dec. 01, 2005
Applicants:
Wayne T. Holcombe, Mountain View, CA (US);
Vitor Pereira, Azueira, PT;
Tiago Marques, Santiago do Cacém, PT;
Inventors:
Wayne T. Holcombe, Mountain View, CA (US);
Vitor Pereira, Azueira, PT;
Tiago Marques, Santiago do Cacém, PT;
Assignee:
Silicon Laboratories, Inc., Austin, TX (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04M 1/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
A ring detect circuit is shown that includes a regenerative latch configured to be coupled to a telephone line. The regenerative latch is configured to generate a fast transient signal in response to a ring signal on the telephone line. The latch is coupled to an isolation transformer through a capacitor. The fast transient passes across the capacitor and through the transformer. A comparator detects the fast transient and, responsive thereto, generates a ring detect signal.