A control circuit for controlling a first transistor includes a diode for suppressing transient voltages. A cathode of the diode is coupled to a first conduction terminal of the first transistor, and an anode of the diode is coupled to a first node. A first resistor is coupled between the first node and a control terminal of the first transistor. A second transistor has a control terminal coupled to the first node, a first conduction terminal configured to receive a first supply voltage, and a second conduction terminal coupled to the control terminal of the first transistor.

The present application discloses new approaches to providing passive-off protection for a B-TRAN-like device. Even if the control circuitry is inactive, AC coupling uses transient voltage on the external terminals to prevent forward biasing an emitter junction. Preferably the same switches which implement diode-mode and pre-turnoff operation are used as part of the passive-off circuit operation.

Rectifiers are used in power systems, but surges are commonly encountered in the power grid, which can damage switches used to drive the active rectifiers. An active rectification system is proposed in which a thyristor type path is enabled through a transistor device such that surges bypass the driving switches.

A method for protecting a power switch during turn-on includes sensing that a change in current through the power switch is in regulation, measuring a time that the change in current through the power switch is in regulation, and comparing the time that the change in current through the power switch is in regulation to a reference time. An over current signal, which can be used to disable the power switch, is generated if the time that the change in current through the power switch is in excess of the reference time.

A power semiconductor circuit includes a power semiconductor device for switching a load, and a comparator which is directly or indirectly connected to the power semiconductor device at a connection point for the load by means of a first input and to which a predefined or predefinable reference voltage can be fed at a second input, the power semiconductor device being activatable by means of an output of the comparator.

An igniter includes a switch element with input, output control electrodes, a first lead in contact with the input electrode and connected to a primary coil of an ignition coil, a second lead that is grounded, a third lead spaced apart from the first and second leads, a first bonding wire connecting the output electrode and the third lead, a second bonding wire connecting the third lead and the second lead, and a control IC that drives the switch element based on an ignition instruction signal from an engine control unit. The control IC generates an ignition confirmation signal based on the voltage of the third lead, and outputs the signal to the engine control unit.

An electrostatic protection circuit includes first and second output terminals, a first diode circuit connected between the first output terminal and a common node, a second diode circuit connected between the second output terminal and the common node, an intermediate voltage circuit that is connected between the first output terminal and the second output terminal and that is configured to generate, at the common node, an intermediate voltage having an intermediate voltage value between a voltage value of the first output terminal and a voltage value of the second output terminal, and a clamp circuit configured to electrically connect the common node to a ground line in accordance with the intermediate voltage.

A power supply device includes an output circuit configured to be supplied with electric power from a power supply, and to output a current, a driving circuit configured to control an output operation of the output circuit to output a current, an overcurrent detection circuit configured to output a detection signal to a first node when detecting an overcurrent in the output circuit, an off-state fixing circuit configured to output an off-state fixing signal to the driving circuit for performing a forcible suspension of the output operation of the output circuit based on a detection signal inputted to the first node, regardless of whether a control signal is outputted, and a control unit configured to receive the detection signal and to output the control signal for controlling the output operation to the driving circuit in order to cause the driving circuit to control the output operation.

A power conversion device includes a power semiconductor switching device and a drive circuit. The power semiconductor switching device is configured to supply constant power to a load by switching and to be turned on and off by a control signal from an external control circuit. The drive circuit is configured to detect an operating temperature of the power semiconductor switching device and drive the power semiconductor switching device according to a result of the detection. The drive circuit includes a temperature detecting unit configured to receive the control signal from the external control circuit and detect the operating temperature of the power semiconductor switching device at timings according to the control signal.

A controller for a semiconductor switch is described that includes a transmitter and a receiver that communicate across galvanic isolation using an inductive coupling. An example controller includes first circuitry referenced to a first reference potential, second circuitry referenced to a second reference potential and galvanically isolated from the first circuitry, and an inductive coupling galvanically isolating the first circuitry and the second circuitry. The inductive coupling includes a first winding referenced to the first reference potential and a second winding referenced to the second reference potential, wherein the first circuitry includes signal reception circuitry coupled to the inductive coupling, wherein the signal reception circuitry includes one or more signal receivers coupled to the first winding to receive signals transmitted over the inductive coupling.