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. 04, 1995
Filed:
Jul. 29, 1992
Bruce W Melvin, Roseville, CA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
An improved interface isolation and selection circuit for a local area network. The invention includes a power supply effective to provide an isolated output voltage. An opto-isolator transforms a first control signal to a second control signal effective to activate the interface. The opto-isolator includes an optical emitter for providing an optical signal in response to the first control signal and an optical detector for receiving the optical signal and providing the second control signal in response thereto. The second control signal is effective to activate the interface by applying the isolated power thereto. In particular implementations, the isolated power and the power for the opto-isolator are provided by a single power supply and a field effect transistor is activated by the opto-isolator and, in turn, activates the interface.