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:
Aug. 30, 1983
Filed:
Sep. 03, 1981
Applicant:
Inventor:
Howard F Jirka, Crystal Lake, IL (US);
Assignee:
Bell Telephone Laboratories, Incorporated, Murray Hill, NJ (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
H02M / ;
U.S. Cl.
CPC ...
363 21 ; 179 / ;
Abstract
A floating, constant power, battery feed circuit wherein a single transformer is used to perform the functions of battery feed and audio coupling. AC feedback is used to control the dynamic output impedance of the circuit. To achieve a constant dynamic output impedance, the amount of AC feedback is controlled by the DC output voltage, which in turn depends on the loop resistance. To achieve a constant audio gain from the switching network to the subscriber set, the audio signal from the switching network is multiplied by a signal representing the DC output voltage.