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:
May. 10, 1977
Filed:
Jul. 28, 1975
Applicant:
Inventor:
Robert G Mathias, Brookfield, IL (US);
Assignee:
Hammond Corporation, Chicago, IL (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03F / ;
U.S. Cl.
CPC ...
330107 ; 330 35 ; 330 86 ;
Abstract
A voltage controlled filter with a plurality of cascaded phase shift circuit stages in a negative feedback path of an amplifier. Each phase shift circuit stage is a RC phase shift network which includes a series capacitor and a field effect transistor (FET) with its source-drain circuit connected as a shunt to ground. The magnitude of the effective source-drain resistance of the FET in each stage is controlled by a DC control voltage which is applied in common to the gate of each FET.
Mathias, Robert. (1977). Voltage controlled filter (U.S. Patent No. 4023113). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/4023113
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile