Renesas Technology Corp.

Fumito Moriyama

Yasuhiro Nunogawa

Shuji Tomono

Osamu Miki

A power source circuit for a high frequency power amplifying circuit, that can be used for a portable telephone of the GSM or WCDMA and a portable telephone capable of performing communications in two or more communication systems such as the GSM and CDMA. The power source circuit is constructed by a first direct current power source circuit such as a series regulator whose power efficiency is not high but which reaches a high level quickly, and a second direct current power source circuit such as a switching regulator, which does not reach the high level quickly but whose power efficiency is high. When the power source voltage has to reach the high level at high speed, both of the series regulator and the switching regulator are simultaneously operated. When the output power source voltage reaches a predetermined level, the operation of the series regulator is stopped.

Power source circuit for high frequency power amplifying circuit and semiconductor integrated circuit for power source and electronics component for power source

Growing community of inventors

Saku, Japan

Fumito Moriyama