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. 19, 1986
Filed:
Jun. 06, 1984
Jean-Claude Froment, Villeneuve-Loubet, FR;
Jean-Pierre Pantani, Saint Jeannet, FR;
Michel Verhaeghe, Vence, FR;
International Business Machines Corp., Armonk, NY (US);
Abstract
A monolithic module acting as the interface between a modem and leased ('LL') or switched ('SL') telephone lines, mainly characterized in that: 1. It can be formed on a silicon chip (due to the absence of electromechanical relays or similar switching means), and 2. Its architecture is such that it makes it possible, by interconnecting or 'stacking' identical modules, not only to attach additional telephone lines, but also to increase the number of allowable modem configurations. The module (10, 10') comprises two controlled-type line amplifiers (DLL, DSL) which exhibit a high output impedance regardless of whether the power supplies are 'on' or 'off'; two controlled-type line receivers (RSL, RLL) which provide a very high input impedance whether the power supplies are 'on' or 'off'; and a wrap receiver (WRP) for testing the modem (to the exclusion of the telephone lines) and interconnecting or 'stacking' identical modules. The figure shows an embodiment wherein two of the modules are interconnected; various configurations can be obtained depending on the logic state of the control inputs (1 to 4 for module 10 and 1' to 4' for module 10') supplied by the modem.