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:
Jul. 19, 2005
Filed:
Nov. 16, 1998
Timothy W. Fuehrer, Phillipsburg, NJ (US);
Keith E. Hollenbach, Reading, PA (US);
Donald R. Laturell, Allentown, PA (US);
Steven B. Witmer, Sinking Spring, PA (US);
Timothy W. Fuehrer, Phillipsburg, NJ (US);
Keith E. Hollenbach, Reading, PA (US);
Donald R. Laturell, Allentown, PA (US);
Steven B. Witmer, Sinking Spring, PA (US);
Agere Systems Inc., Allentown, PA (US);
Abstract
Disclosed is a method and apparatus which facilitates the use of existing power that is ordinarily unused or discarded to provide power to a telephone interface circuit when the circuit is in the on-hook state, thereby alleviating the need to use loop current to power the interface during the on-hook state. Existing clock signals are used to charge capacitors that are normally used for capacitive coupling of digital data across the high voltage isolation barrier. Although only small-value capacitors are needed for transmitting data across the capacitive interface, larger-value capacitors are used and are configured to form a charge pump to generate power to the interface at all times. Thus the interface always has a steady source of power available for use, including during the on-hook state for powering circuitry that can detect, modulate, and transmit on-hook signals across the capacitive interface.