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:
Apr. 08, 1986
Filed:
Apr. 23, 1984
Richard H Hock, Hopatcong, NJ (US);
AT&T Bell Laboratories, Murray Hill, NJ (US);
Abstract
A current converter circuit that supplies send and return currents to a balanced transmission line includes current sensing circuitry that responds to a current unbalance or a differential current, independently of longitudinal currents in the balanced line. A reference voltage and two inputs to a comparator monitor the voltage drop across a voltage divider connecting the send and return leads of the transmission line. The voltage divider has a grounded center tap so that longitudinal currents flow to ground and provide equal and opposite polarity voltages across the divider, which cancel each other. Unbalanced currents provide a corresponding differential voltage input to the comparator, whose control voltage output is utilized to initiate corrective action in a current control circuit.