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. 07, 1979
Filed:
Mar. 01, 1978
Applicant:
Inventors:
Wendell W Damm, Aloha, OR (US);
Choong R Kim, Aloha, OR (US);
Assignee:
Tektronix, Inc., Beaverton, OR (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03F / ; H03F / ;
U.S. Cl.
CPC ...
330252 ; 330 59 ; 330308 ;
Abstract
A differential amplifier includes an input stage and an output stage which are electrically isolated from each other to permit the input and output portions of the circuit to be operated at different voltage levels. A pair of optical couplers are employed to couple the differential signal from the input stage to the output stage. The output stage comprises a linear gain cell to provide an output signal proportional to the differential signal through the couplers divided by the common-mode signal through the couplers to stabilize gain and minimize D.C. offset drift caused by small changes in physical parameters or temperature.