Power amplification circuit

• Main Author: KENICHI SHIMAMOTO
• Format: Patent
• Language: Chinese; English
• Published: 09.06.2017
• Subjects: AMPLIFIERS; BASIC ELECTRONIC CIRCUITRY; ELECTRICITY

A power amplification circuit includes: a first amplification transistor, a first signal being input to a base or gate thereof and a second signal obtained by amplifying the first signal being output from a collector or drain thereof; and a first bias circuit that supplies a first bias current to the base or gate of the first amplification transistor. The first bias circuit includes a first transistor that outputs the first bias current from an emitter or source thereof, and a first control circuit that controls an electrical connection between the emitter or source of the first transistor and ground. The first control circuit includes a first resistance element and a first switch element, which are connected in series with each other. The first switch element is switched on in the case of a first power mode and is switched off in the case of a second power mode. 本发明能够抑制增益特性的劣化，并且降低消耗电流。功率放大电路具备：第1放大晶体管，该第1放大晶体管将第1信号输入至基极或栅极，从集电极或漏极输出将第1信号放大后的第2信号；以及第1偏置电路，该第1偏置电路向第1放大晶体管的基极或栅极提供第1偏置电流，第1偏置电路具备：从发射极或源极输出第1偏置电