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:
Jan. 23, 2001
Filed:
Feb. 19, 1999
Hisaya Ishihara, Kanagawa, JP;
NEC Corporation, Tokyo, JP;
Abstract
A variable gain amplifier circuit enables the minimum gain to be established easily without changing DC voltage of output terminal at the time when the gain is to be variable. The variable gain amplifier circuit is provided with an input differential circuit consisting of a first and a second transistors whose respective bases are connected to input terminals, and whose respective emitters are connected to constant-current source, and a gain control differential circuit consisting of a third to an eighth transistors,and,which are connected mutually such that base, collector, and emitter become required relationship. Further, the variable gain amplifier circuit is provided with a first load resistor connected between collector of the third, fifth, and seventh transistors,and,and a first power supply terminal, and a second load resistor connected between collector of the sixth, eighth, and fourth transistors,and