Kabushiki Kaisha Toshiba

Toshiba Electronic Devices & Storage Corporation

Kazuyasu Minami

Takaya Yasuda

Hirotoshi Aizawa

Yasuhiro Kakitsuka

A current detection circuit includes an N-type first transistor configured to supply a first current to an output terminal, an N-type second transistor that constitutes a current mirror circuit with the first transistor, a comparison circuit configured to output a detection result showing whether or not the first current is larger than a predetermined threshold based on a current flowing through the second transistor, a ground fault detection circuit configured to output a result detecting a ground fault of the output terminal, and a logical circuit configured to output a current detection signal showing whether or not the first current is an overcurrent based on the detection result of the comparison circuit and the ground fault detection result of the ground fault detection circuit.

Current detection circuit

An amplifier circuit includes, a first transistor and a first resistor connected in series between a power supply voltage and an output terminal. A second transistor and a second resistor are connected in series between the output terminal and a ground reference voltage. There is a first operational amplifier and a second operational amplifier. A first detection current corresponding to a voltage drop across first resistor is generated. A second detection current corresponding to a voltage drop across the second resistor is generated. A first replication circuit subtracts the second detection current from the first detection current. A third resistor conducts the current obtained by subtracting the second detection current from the first detection current.

Amplifier circuit

A load modulation circuit of an embodiment has a first element, a switch element configured to connect the first element to an end portion of a coil, a first control section configured to control an operation of the switch element, and a second control section configured to control an amount of electric charges accumulated in the first element, and the second control section discharges the electric charges accumulated in the first element when the switch element is switched to off.

Growing community of inventors

Yokohama Kanagawa, Japan

Kazuyasu Minami