US 11,817,837 B2
Power amplifier circuit
Yuri Honda, Kyoto (JP); Satoshi Tanaka, Kyoto (JP); Yasuhisa Yamamoto, Kyoto (JP); and Hiroki Shonai, Kyoto (JP)
Assigned to MURATA MANUFACTURING CO., LTD., Kyoto (JP)
Filed by Murata Manufacturing Co., Ltd., Kyoto (JP)
Filed on Dec. 21, 2020, as Appl. No. 17/129,041.
Claims priority of application No. 2019-234496 (JP), filed on Dec. 25, 2019.
Prior Publication US 2021/0203289 A1, Jul. 1, 2021
Int. Cl. H03F 3/45 (2006.01); H03F 3/24 (2006.01); H03F 3/195 (2006.01)
CPC H03F 3/245 (2013.01) [H03F 3/195 (2013.01); H03F 2200/102 (2013.01); H03F 2200/171 (2013.01); H03F 2200/451 (2013.01); H03F 2200/537 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A power amplifier circuit having an input node to which a high-frequency signal is input and an output node from which an amplified high-frequency signal is output, the high-frequency signal being amplified by a differential amplifier circuit, the power amplifier circuit comprising:
a balun transformer comprising an input-side winding that is connected between differential outputs of the differential amplifier circuit, and an output-side winding that is coupled to the input-side winding via an electromagnetic field and that has a first end connected to a reference potential;
a capacitive element between a second end of the output-side winding and the output node; and
a band pass filter between the second end of the output-side winding and the output node, the band pass filter comprising the capacitive element,
wherein the input-side winding has a substantially centered tap, and
wherein a power-supply voltage is supplied to the substantially centered tap.