Korea Advanced Institute of Science and Technology

Samsung Electro-mechanics Co., Ltd.

Lg Electronics Inc.

Seung Hoon Kang

Gyu Suck Kim

Song Cheol Hong

Jaehoon Chung

Minki Ahn

Jinseok Park

Song-Cheoll Hong

Provided is a phase shifting device including a first balun outputting first and second differential input signals, an I/Q generator outputting first to fourth phase signals based on the first and second differential input signals, a control circuit outputting a first control signal, a second control signal, a plurality of in-phase select signals, and a plurality of quadrature select signals, a current source circuit including a first source transistor outputting an in-phase current according to the first control signal and a second source outputting a quadrature current according to the second control signal, a vector sum circuit outputting first and second differential output signals based on the first to fourth phase signals according to the plurality of in-phase select signals and the plurality of quadrature select signals and including a plurality of sub-vector sum circuits, and a second balun outputting an output signal.

Phase shifting device

A power amplifier according to examples includes an amplifying circuit configured to amplify an input signal, a feedback circuit configured to feedback the amplified signal to the amplifying unit, and a feedback controlling circuit configured to control a power of the fed-back signal based on a power of the input signal. The feedback controlling unit performs controlling so that the power of the fed-back signal is increased as the power of the input signal is increased.

Power amplifier

A power amplifier include an amplifier including at least one field effect transistor (FET) that operates in an amplifying stage configured to amplify an input signal, and a body controller configured to control a bias voltage of a body terminal of the FET based on a power of the input signal. The body controller performs controlling so that the bias voltage of the body terminal is reduced in response to the power of the input signal being increased. Accordingly, such a power amplifier exhibits improved linearity.

Growing community of inventors

Daejeon, South Korea

Seung Hoon Kang