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. 21, 1987
Filed:
Oct. 15, 1985
Michael R Ferland, Nashua, NH (US);
Roger V Burns, Jr, Plymouth, MA (US);
J Anson Whealler, Jr, Cohasset, MA (US);
Teradyne, Inc., Boston, MA (US);
Abstract
Apparatus for measuring the difference between two voltages in which a first current proportional to the voltage difference is generated at a first point, and there is circuitry for delivering at a second point a second current that is based on the first current and is indicative of the voltage difference; the circuitry includes an uninterrupted current path from the first point to the second point and the current path has a circuit element across which at least a portion of the common mode voltage appears; and the circuit element provides an output current to the path which is independent of the voltage across the circuit element.