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.

Date of Patent:
Jul. 28, 2020

Filed:

Mar. 16, 2018
Applicant:

Fujitsu Limited, Kawasaki-shi, Kanagawa, JP;

Inventor:

Yasufumi Sakai, Fuchu, JP;

Assignee:

FUJITSU LIMITED, Kawasaki, JP;

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03F 3/45 (2006.01); H03F 1/02 (2006.01); H04B 10/516 (2013.01); H03F 1/08 (2006.01); H03F 3/08 (2006.01); H04B 10/40 (2013.01);
U.S. Cl.
CPC ...
H03F 3/45215 (2013.01); H03F 1/0216 (2013.01); H03F 1/0261 (2013.01); H03F 1/086 (2013.01); H03F 3/082 (2013.01); H03F 3/45381 (2013.01); H04B 10/516 (2013.01); H03F 2200/21 (2013.01); H03F 2200/555 (2013.01); H03F 2203/45022 (2013.01); H03F 2203/45151 (2013.01); H03F 2203/45154 (2013.01); H03F 2203/45178 (2013.01); H03F 2203/45674 (2013.01); H03F 2203/45702 (2013.01); H04B 10/40 (2013.01);
Abstract

An amplifier circuit includes: an amplifier; and a bias circuit that controls an operation point of the amplifier. The amplifier includes: a load resistor; a differential transistor pair electrically coupled to the load resistor; and a tail transistor electrically coupled to the differential transistor pair. The bias circuit includes: a voltage generator circuit that generates a reference voltage corresponding to a sum of a threshold voltage of a transistor in the differential transistor pair and a saturation drain voltage of the tail transistor; and a current generator circuit that generates a reference current that is proportional to a difference between a power supply voltage of the amplifier circuit and the reference voltage by using a reference resistor. The current generator circuit is electrically coupled to the amplifier such that a tail current that flows through the tail transistor is proportional to the reference current.


Find Patent Forward Citations

Loading…