A power semiconductor module having switching elements includes: a collector main terminal and a collector auxiliary terminal connected to a collector potential of the switching element; a gate auxiliary terminal connected to a gate potential of the switching element; and an emitter main terminal and an emitter auxiliary terminal connected to an emitter potential of the switching element. A power converter includes a voltage dividing circuit board that generates a divided voltage obtained by dividing a voltage between the collector auxiliary terminal and the emitter auxiliary terminal and transmits to a gate driving circuit. The voltage dividing circuit board is electrically connected to the collector auxiliary terminal and the emitter auxiliary terminal. A gate driving circuit changes a driving speed of the switching element according to the divided voltage.

A switching device includes an insulated gate bipolar transistor (IGBT) or MOSFET having a gate, an emitter, and a collector configured to allow current to pass between the emitter and the collector based on voltage applied to the gate. A stack of alternating layers of photo-sensitive p-n junction layers and insulating layers stacked on the gate for optical switching control of voltage through the IGBT or MOSFET.

Method and device for safe switching of a signal between a first and second point. Device includes a first branch having a first switch and second switch arranged between the first and second point, and a parallel second branch having a third switch and fourth switch. A testing device instructs a control unit, in a test sequence, to open the first switch for a first period of time, open the second switch for a second period of time, open the third switch for a third period of time, and open the fourth switch for a fourth period of time. Neither the first nor second periods of time overlap with the third or fourth period of time. A testing unit tests functioning of the switches during respective period of time, and generates an error signal in the event of a malfunction of at least one switch.

The invention discloses a standby control circuit and a display device. The standby control circuit includes a standby module, at least one power board, and a transistor switch control module comprising at least one transistor switch whose number is equal to that of the at least one power board, each transistor switch is connected between one power board and a mains supply input terminal, the standby module is configured to generate a trigger signal and send the generated trigger signal to each transistor switch, and each transistor switch is configured to be turned on upon receipt of the trigger signal sent from the standby module so as to connect the power board connected thereto with the mains supply input terminal.

A digital output circuit to be driven by an insulated power-supply circuit includes a transistor to turn on/off an external power supply in accordance with a signal output by a light receiving element in an insulating circuit in response to a signal processed by a controller. The external supply is connected to an output device. The output circuit includes a switching unit having first and second mechanisms to switch each of wires between a connected state and a non-connected state at two places between the light receiving element and the source or emitter of the transistor, and a logic adjusting unit to adjust inversion of a logic output of the light receiving element in correspondence to the type of the transistor, such that the output circuit is switched between a sink-current type and a source-current type.

A digital output circuit to be driven by an insulated power-supply circuit includes a transistor to turn on/off an external power supply in accordance with a signal output by a light receiving element in an insulating circuit in response to a signal processed by a controller. The external supply is connected to an output device. The output circuit includes a switching unit having first and second mechanisms to switch each of wires between a connected state and a non-connected state at two places between the light receiving element and the source or emitter of the transistor, and a logic adjusting unit to adjust inversion of a logic output of the light receiving element in correspondence to the type of the transistor, such that the output circuit is switched between a sink-current type and a source-current type.

An optocoupler is placed in series between the field ground pin of digital input circuitry and the field ground of an industrial controller. A capacitor to field ground is provided for each digital input. A resistor is provided to the input pin of the digital input circuitry. To detect a broken wire a test pulse is provided to the optocoupler connected in the ground path. This test pulse isolates the digital input circuitry from field ground. As current is always being provided from the field when the wire is not broken, the capacitor connected between the input and ground charges. After the test pulse has completed, the output signal of the digital input circuitry is examined. If the level indicates the input is high, the wire is not broken. If, however, the output remains low indicating that the input is low, the wire has broken.

A solar photovoltaic module safety shutdown system includes a module-on switch coupled with a first circuit having a photovoltaic module and a System-Monitor device. The System-Monitor device couples to the module-on switch through a second circuit and to the photovoltaic module and an AC main panelboard through the first circuit. A module-off switch operatively couples with the photovoltaic module and the module-on switch. The System-Monitor device supplies a System-on signal to the module-on switch through the second circuit. The module-on switch disables the photovoltaic module by shorting it or disconnecting it from the first circuit in response to the System-On signal not being received by the module-on switch from the System-Monitor device. The module-off switch disables the photovoltaic module by shorting it in response to the System-On signal not being received by the module-on switch when the photovoltaic module is irradiated with light.

An isolation system and isolation device are disclosed. An illustrative isolation device is disclosed to include first circuitry having at least a first emitter and a first detector, second circuitry having at least a dual-purpose component, an isolation material configured to electrically isolate the first circuitry from the second circuitry, and switching circuitry adapted to connect the dual-purpose component to emit a first signal for detection by the first detector in a first configuration, and to receive a second signal from the first emitter in a second configuration.

A semiconductor module includes a photocoupler, a gate driving IC, and a switching element, and at least one of a first structure and a second structure, wherein the first structure is a structure where in a part of a surface of a first lead frame joined to a bottom surface electrode of a light-emitting element, a first conductive layer is disposed with an insulating layer interposed, and a top surface electrode of the light-emitting element, and the first conductive layer are electrically connected by a wire, and the second structure is a structure where in a part of a surface of a second lead frame joined to a bottom surface electrode of a light-receiving element, a second conductive layer is disposed with an insulating layer interposed, and a top surface electrode of the light-receiving element, and the second conductive layer are electrically connected by a wire.