Patents by Inventor Cyushiro Kusano

Cyushiro Kusano has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • High-frequency power amplification module and radio communication device
    Patent number: 6636118
    Abstract: In a high frequency power amplifier module of a multi-stage structure in which a plurality of heterojunction bipolar transistors (npn-type HBTs) are cascade-connected, a protection circuit in which a plurality of pn junction diodes are connected in series is connected between the collector and emitter of each HBT. The p-side is connected to the collector side, and the n-side is connected to the emitter side. A protection circuit in which pn junction diodes of the number equal to or smaller than that of the pn junction diodes are connected in series is connected between the base and the emitter. The p-side is connected to the base side, and the n-side is connected to the emitter side. With the configuration, in the case where an overvoltage is applied across the collector and emitter due to a fluctuation in load on the antenna side, the collector terminal is clamped by an ON-state voltage of the protection circuits, so that the HBT can be prevented from being destroyed.
    Type: Grant
    Filed: November 14, 2001
    Date of Patent: October 21, 2003
    Assignees: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Cyushiro Kusano, Eiichi Hase, Hideyuki Ono, Osamu Kagaya, Yasunari Umemoto, Takahiro Fujita, Kiichi Yamashita