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:
Apr. 15, 2008
Filed:
Jul. 05, 2005
Jae-young Ryu, Suwon-si, KR;
Hyun-koo Kang, Yongin-si, KR;
Dae-yeon Kim, Suwon-si, KR;
Jeong-ho Lee, Suwon-si, KR;
Jae-young Ryu, Suwon-si, KR;
Hyun-koo Kang, Yongin-si, KR;
Dae-yeon Kim, Suwon-si, KR;
Jeong-ho Lee, Suwon-si, KR;
Samsung Electronics Co., Ltd., Suwon-si, KR;
Abstract
A variable gain amplifier (VGA) having stable input impedance matching and a stable noise figure in spite of a variation of an amplification gain is provided. In an embodiment of the VGA, a first stage of a cascode amplification unit has a fixed impedance regardless of a change of an amplification gain, and a variable gain determination unit comprised of a plurality of transistors is formed at an upper stage in the cascode amplification unit. Accordingly, a change of an input impedance of the cascode amplification unit due to the change of the amplification gain is minimized. In another embodiment of the VGA, an amplification gain of an amplification unit is controlled by adjusting a voltage applied to the amplification unit by controlling a current to be output by a current supply source, and stable input impedance matching and a stable noise figure are obtained.