Rohm Co., Ltd.

Muga Imamura

Naoki Takahashi

Masaki Omi

Yohei Okuno

Shuntaro Takahashi

Takashi Fujimura

Hirofumi Yuki

Katsuaki Yamada

A switching device includes: an N-type semiconductor substrate; a power MISFET having the N-type semiconductor substrate as its drain; an input electrode receiving an input signal; a control circuit generating a gate control signal for the power MISFET according to the input signal; and a negative current prevention circuit provided between the input electrode and the control circuit. The negative current prevention circuit includes: a P-channel MISFET connected, with its drain toward the input electrode and its source and back gate toward the control circuit, between the input electrode and the control circuit, with its gate fed with a fixed potential, with the potential at its back gate separated from the potential of the N-type semiconductor substrate; and a diode connected, with its anode toward the input electrode and its cathode toward the control circuit, between the input electrode and the control circuit.

Switching device, electronic appliance, and vehicle

An antenna driving device includes an antenna driving circuit arranged to generate driving current of a transmission antenna, a power supply circuit arranged to generate an output voltage from an input voltage so as to supply the output voltage to the antenna driving circuit, and a logic circuit arranged to control the antenna driving circuit and the power supply circuit. The power supply circuit has a function of temporarily disabling current feedback control so as to perform voltage feedback control using a reference value just before halting the drive of the transmission antenna when the power supply circuit restarts to drive the transmission antenna, or has a function of performing variable control of a reference value for current feedback control in accordance with a rising edge of the driving current when the power supply circuit restarts to drive the transmission antenna.

Antenna driving device

A semiconductor device has a first chip and a second chip sealed in a single package. The first chip includes a regulator which generates an internal voltage from a supply voltage, a reset circuit which monitors the supply voltage and the internal voltage to generate a reset signal, and a controlled circuit which operates by being supplied with the supply voltage. The second chip includes a controlling circuit which generates a control signal for the controlled circuit by being supplied with the internal voltage. The reset signal is fed to both the controlling circuit and the controlled circuit.

Semiconductor device, electronic appliance, and vehicle

Growing community of inventors

Kyoto, Japan

Muga Imamura