Patent ID: 11894816
Assignee: MURATA MANUFACTURING CO., LTD.
Field: Basic communication processes (Electrical engineering)
Classification: CPC H | IPC H

Claim 12:
13. A power amplifier circuit comprising:
an amplifier configured to amplify a first radio frequency (RF) signal supplied to the amplifier, and to output a second RF signal;
a bias circuit configured to supply a bias current or a bias voltage to the amplifier; and
a bias adjustment circuit configured to adjust the bias current or the bias voltage based on the first RF signal or the second RF signal,
wherein the bias adjustment circuit comprises a first diode having an anode to which a signal based on the first RF signal or the second RF signal is input, and a cathode connected to a ground,
the bias circuit comprises a bias transistor configured to output the bias current or the bias voltage based on a voltage at the anode of the first diode,
wherein the amplifier has a supply terminal to which the first RF signal is supplied, and an output terminal from which the second RF signal is output,
wherein the bias transistor has an emitter connected to the supply terminal,
wherein the anode of the first diode is connected to the output terminal, and
wherein the bias transistor has a base connected to the anode of the first diode.