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:
Jul. 17, 1984
Filed:
Dec. 03, 1981
Applicant:
Inventor:
Sven Mattisson, Bjarred, SE;
Assignee:
Inventab Audio Kb, Lund, SE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03F / ;
U.S. Cl.
CPC ...
330252 ; 330256 ; 330149 ;
Abstract
A low noise amplifier circuit (FIGS. 4 and 5) is disclosed including plural differential amplifiers having their inputs and outputs connected to common input and output lines (50, 52; 54, 56). In the disclosure, each differential amplifier is comprised of a pair of bipolar junction transistors (40, 42; 58, 60; 64, 66) of the same type. Parallel connecting of the differential amplifiers in the disclosed fashion reduces the Johnson noise introduced by the base spreading resistances of the individual transistors. Since differential amplifiers, per se, are connected in parallel rather than their component transistors, thermal runaway is not a problem.