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. 09, 1994
Filed:
Dec. 16, 1992
Mark Jordan, Goffstown, NH (US);
Unitrode Corporation, Billerica, MA (US);
Abstract
An active negation emulator circuit for improving the noise margin of signals carried by a signal interface bus. The circuit includes a sensor for sensing the voltage on the bus and a variable current source for supplying a current to the bus when the voltage level thereon is greater than a predetermined value. More particularly, when the voltage level on the bus is indicative of the signal carried thereby being in a logic high state, a current is supplied to raise the voltage level to the desired logic high voltage level. A combination circuit is also provided including an active negation emulator circuit, a resistive terminator, and switch means for selectively coupling the active negation emulator to the signal interface bus, coupling the resistive terminator to the signal interface bus, or decoupling both the emulator and the terminator from the bus, in accordance with the location of the bus to which the combination circuit is coupled.