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. 27, 2015
Filed:
Feb. 27, 2013
Applicant:
Sumitomo Electric Industries, Ltd., Osaka, JP;
Inventors:
Assignee:
Sumitomo Electric Industries, Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03F 3/45 (2006.01); H03F 3/08 (2006.01);
U.S. Cl.
CPC ...
H03F 3/4508 (2013.01); H03F 3/087 (2013.01); H03F 3/45085 (2013.01); H03F 3/45475 (2013.01); H03F 3/45556 (2013.01); H03F 2200/447 (2013.01); H03F 2203/45008 (2013.01); H03F 2203/45078 (2013.01);
Abstract
A differential circuit with a function to compensate the gain enhancement due to the self-heating of the transistor is disclosed. The differential circuit includes an equalizer unit coupled with one of paired transistors. The other of the paired transistor receives the input signal to be amplified. The base level, or the base-emitter bias, is oppositely modulated by the input signal through the common emitter, which causes the modification of the base current. The equalizer unit reduces the variation of the base level only in low frequencies where the self-heating effect of the transistor appears.