US 12,273,079 B2
Power amplifier circuit, high frequency circuit, and communication apparatus
Kenji Tahara, Kyoto (JP); Kenichi Shimamoto, Kyoto (JP); and Yusuke Tanaka, Kyoto (JP)
Assigned to MURATA MANUFACTURING CO., LTD., Kyoto (JP)
Filed by MURATA MANUFACTURING CO., LTD., Kyoto (JP)
Filed on Jun. 3, 2022, as Appl. No. 17/805,259.
Application 17/805,259 is a continuation of application No. PCT/JP2020/031128, filed on Aug. 18, 2020.
Claims priority of application No. 2019-232950 (JP), filed on Dec. 24, 2019.
Prior Publication US 2022/0294401 A1, Sep. 15, 2022
Int. Cl. H03F 1/07 (2006.01); H03F 1/02 (2006.01); H03F 3/195 (2006.01); H03F 3/24 (2006.01)
CPC H03F 3/245 (2013.01) [H03F 1/0222 (2013.01); H03F 3/195 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A power amplifier circuit configured to amplify power of a high frequency signal, comprising:
a first transistor that has a first base, a first collector, and a first emitter;
a second transistor that has a second base, a second collector, and a second emitter, the second base being connected to the first collector;
a third transistor that has a third base, a third collector, and a third emitter, the third base being connected to the first collector, the third collector being connected to the second collector;
a first bias circuit that comprises a fourth transistor connected to the first base;
a second bias circuit that comprises a fifth transistor connected to the second base;
a third bias circuit that comprises a sixth transistor connected to the third base;
a first current limiting circuit; and
a second current limiting circuit,
wherein the fourth transistor has a fourth base, a fourth collector, and a fourth emitter,
wherein the fifth transistor has a fifth base, a fifth collector, and a fifth emitter,
wherein the sixth transistor has a sixth base, a sixth collector, and a sixth emitter,
wherein the first current limiting circuit comprises:
a seventh transistor having a seventh base, a seventh collector, and a seventh emitter, the seventh emitter being connected to the fifth emitter,
a first collector resistor that has a first end and a second end, the first end being connected to the seventh collector, the second end being connected to the first collector, and
a first base resistor that has a first end and a second end, the first end being connected to the seventh base, the second end being connected to the fifth base,
wherein the second current limiting circuit comprises:
an eighth transistor that has an eighth base, an eighth collector, and an eighth emitter, the eight emitter being connected to the sixth emitter,
a second collector resistor that has a first end and a second end, the first end being connected to the eighth collector, the second end being connected to the first collector, and
a second base resistor that has a first end and a second end, the first end being connected to the eighth base, the second end being connected to the sixth base,
wherein a resistance of the first base resistor is different from a resistance of the second base resistor, or wherein a resistance of the first collector resistor is different from a resistance of the second collector resistor.