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:
Sep. 27, 2005
Filed:
Apr. 02, 2002
Leonel E. Enriquez, Melbourne Beach, FL (US);
Douglas L. Youngblood, Palm Bay, FL (US);
Leonel E. Enriquez, Melbourne Beach, FL (US);
Douglas L. Youngblood, Palm Bay, FL (US);
Intersil Americas Inc., Milpitas, CA (US);
Abstract
A voltage reference filter for a subscriber line interface circuit removes unwanted noise on a DC reference voltage sourced by a device, such as a codec, and employed by the subscriber line circuit as a differential mode voltage baseline. The DC reference voltage is coupled via a high pass filter to the sense amplifier. The filter blocks the DC component of the reference voltage and passes noise components to the sense amplifier. The reference port of an amplifier between the sense amplifier and a codec receives the same (noisy) reference voltage AC-coupled to the sense amplifier, and performs common mode rejection of noise components riding on the DC reference.