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, 1992
Filed:
May. 29, 1990
Ulrich Riedle, Feldkirchen-Westerham, DE;
Siemens Aktiengesellschaft, Munich, US;
Abstract
An interface between a bidirectional transmission channel with analog signals and four-wire input of a digital communication system. In order to enable a formatting of the interface as an integrated module in 10 V technology, a repeater or transformer is operated as an attenuation element in a lower frequency range and the transmission or, respectively, terminating impedance is selected such that all signalization voltages are transformed into a range that can be evaluated in 10 V technology, whereby, for suppressing higher-frequency noise signals, the signalization voltages are supplied via a low-pass filter to a ringing signal detector or, respectively, via a selective band-pass filter to a call charge signal detector.