Hitachi, Ltd.

Kabushiki Kaisha Toshiba

Nec Corporation

Nippon Telegraph and Telephone Corporation

Kaoru Kato

Chiaki Hirai

Chisa Nagai

Tohru Nojiri

Takaaki Ishii

Katsumi Ishikawa

Noboru Saegusa

Ayumu Hatanaka

Akio Yotsutani

Isao Sasaki

Kunihiko Kido

Hisaya Ishibashi

Naoki Maru

Kazuhiro Yoshizawa

Akio Toki

Yuuichi Kurosawa

Yukiko Morimoto

Futoshi Koike

Tatsuya Nakae

Masayoshi Yoshimoto

Kazuhiro Ikegaya

Display screen with graphical user interface

Display screen or portion thereof with graphical user interface

The dead time is secured stably in a semiconductor drive circuit for switching devices using a wide band gap semiconductor. The drain terminal of the switching device of an upper arm is connected to the positive terminal of a first power supply, the source terminal of the switching device of a lower arm is connected to the negative terminal of the first power supply, and the source terminal of the switching device of the upper arm is connected with the drain terminal of the switching device of the lower arm. A gate drive circuit provided for each switching device includes an FET circuit and a parallel circuit made of a parallel connection of a first resistor and a first capacitor and having a first terminal connected to the gate terminal of the switching device.

Semiconductor drive circuit and power conversion apparatus using same

In a radio telephone system comprising a radio telephone set utilizing a rechargeable battery, and a base unit connected to the radio telepone set through a radio channel for exchanging a speech signal between the radio telephone set and a wired telephone line, there are provided a detector for detecting the charged state of the battery, a terminating device responsive to the output signal of the detector for terminating the radio channel between the radio telephone set and the base unit.

Radio telephone system and method for controlling same

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Tokyo, Japan

Kaoru Kato