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:
Mar. 04, 2008
Filed:
Jun. 30, 2006
Kouichiro Yamaguchi, Tokyo, JP;
Kouichiro Yamaguchi, Tokyo, JP;
Icom Incorporated, , JP;
Abstract
Variable gain amplifier includes signal amplifying transistor, and gain control transistors at output and non-output sides. Emitters or sources of gain control transistors at output and non-output sides are connected to collector or drain of signal amplifying transistor. Output load is connected between collector or drain of gain control transistor at output side and power source side. Load is connected between collector or drain of gain control transistor at non-output side and power source side. Output load and load have the same impedance. Negative feedback path is connected between output end of gain control transistor at output side and input end of signal amplifying transistor. Negative feedback path is also connected between output end of gain control transistor at non-output side and input end of signal amplifying transistor. Two negative feedback paths have the same circuit constant. A differential amplifier is formed of a pair of such variable gain amplifiers.