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. 11, 1997
Filed:
Sep. 19, 1995
Alps Electric Co., Ltd., Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A grounded-base transistor amplifier including a pair of transistors which have the bases thereof grounded at a high frequency and the collectors thereof coupled to a signal output terminal, a high frequency transformer which includes a primary winding connected to a signal input terminal and a secondary winding equipped with a midpoint tap, both ends of the secondary winding being connected to the emitters of the transistors, and a constant-current circuit which is connected to the midpoint tap of the secondary winding and which produces a bias current flow through the transistors. Noise voltages generated by the constant-current circuit are supplied to the emitters of the transistors in the same phase via the secondary winding; therefore, no noise voltage appears at the signal output terminal.