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:
Feb. 19, 1980
Filed:
Sep. 29, 1978
Applicant:
Inventors:
Kenneth D Lawson, Cataumdet, MA (US);
Neil L Brown, Falmouth, MA (US);
Assignee:
Neil Brown Instruments Systems, Inc., Cataumet, MA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03F / ;
U.S. Cl.
CPC ...
330109 ; 330294 ;
Abstract
An active filter which can achieve extremely high attenuation of frequencies outside the passband while maintaining a very low phase shift of signals within the passband. A preferred embodiment is described in which two, second-order, multiple-feedback, active filter circuits are cascaded and the output of the second filter is fedback to the input of the first filter to realize a fourth-order filter which has very high attenuation of signals falling outside the passband while providing very low phase shifts of signals within the passband.