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:
Dec. 29, 1987
Filed:
Feb. 26, 1987
Applicant:
Inventors:
Larry E Eccleston, Edmonds, WA (US);
John C Emery, Everett, WA (US);
Assignee:
John Fluke Mfg. Co., Inc., Everett, WA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03M / ;
U.S. Cl.
CPC ...
3403 / ; 307571 ; 307572 ;
Abstract
In a circuit utilizing a digital to analog converter, an amplifier receives two voltage levels of a digitally modulated input signal via two different switching circuits. Linearity of output signals provided by the amplifier is significantly improved by a circuit for effectively matching the resistances provided by the two switching circuits to the amplifier. A feedback circuit from the output of the amplifier, including a feedback amplifier, is used to withdraw from a switching device any current passing therethrough when ON, thus eliminating any effect of resistance of the switching device from the amplifier.