Murata Manufacturing Co., Ltd.

Shingo Uda

Yoshihiro Imanishi

Kota Takayama

Yu Ishiwata

Tatsumasa Kawahara

A transmission line includes three wires formed on a substrate. Each of the transmission lines transmits a three-level signal. A common-mode choke coil is inserted into the transmission line. The common-mode choke coil includes three coils coupled to one another and three pairs of outer electrodes, each of the three pairs being connected to the corresponding two ends of the coils. The outer electrodes of the common-mode choke coil are connected to the transmission line such that the three coils are serially inserted into the respective three wires.

Noise filter implementation structure

A power supply circuit includes a plurality of power amplifiers for amplifying radio frequency signals, an envelope tracker for supplying a variable voltage based on an envelope signal to the power amplifiers, a common line connected to an output side of the envelope tracker, and a plurality of branch lines branching from a tip of the common line and connected to the power amplifiers, respectively. On the branch lines, sub-inductors are provided, respectively. On the common line, a main inductor and a capacitor are provided.

Growing community of inventors

Nagaokakyo, Japan

Shingo Uda