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. 28, 1987
Filed:
Sep. 24, 1985
Applicant:
Inventor:
Gyula Jakab, Nepean, CA;
Assignee:
Northern Telecom Limited, Montreal, CA;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04M / ; H03K / ;
U.S. Cl.
CPC ...
379412 ; 307565 ; 307318 ; 361119 ; 361 91 ;
Abstract
An integrated SLIC having input pins coupled to the wires of a two-wire telephone subscriber line is protected from excessive voltages on the line by reverse biassed 60 volt zener diodes connected between each input pin and ground, normally reverse biassed diodes within the integrated circuit connected between each input pin and the substrate of the integrated circuit, and a normally forward biassed diode connected between the substrate and a -48 volt (nominal) supply voltage.