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. 29, 1998
Filed:
May. 31, 1996
Jeffrey P Davis, Ham Lake, MN (US);
Duane Francis Wald, Plymouth, MN (US);
Timothy D Gunn, Mounds View, MN (US);
Multi-Tech Systems, Inc., Mounds View, MN (US);
Abstract
A communications interface having an isolation circuit for signals from a plain old telephone set (POTS) device to communications electronics. The communications interface having an isolated power supply. The isolated power supply including a flyback transformer for a current loop supply and an isolated power source The telephone line isolation circuit having an optically isolated off-hook detection circuit and an isolation transformer for isolating communication electronics from the telephone current loop. The telephone line isolation circuit providing a ringing circuit for ringing a current loop device, such as a standard plain old telephone system (POTS) device.