A load control device for controlling power delivered from an AC power source to an electrical load may have a closed-loop gate drive circuit for controlling a semiconductor switch of a controllably conductive device. The controllably conductive device may be coupled in series between the source and the load. The gate drive circuit may generate a target signal in response to a control circuit. The gate drive circuit may shape the target signal over a period of time and may increase the target signal to a predetermined level after the period of time. The gate drive circuit may receive a feedback signal that indicates a magnitude of a load current conducted through the semiconductor switch. The gate drive circuit may generate a gate control signal in response to the target signal and the feedback signal, and render the semiconductor switch conductive and non-conductive in response to the gate control signal.

According to the present disclosure, the deterioration of SiC-MOSFETs is suppressed. A drive device switches between a first SiC-MOSFET and a second SiC-MOSFET that are connected in series, with a dead time where the first SiC-MOSFET and the second SiC-MOSFET are commanded to be OFF being provided in between. This drive device includes: a first drive circuit configured to set the gate voltage of the first SiC-MOSFET, during the dead time, to a first middle voltage that is higher than a first negative power supply voltage and lower than a first threshold voltage for the first SiC-MOSFET; and a second drive circuit configured to set the gate voltage of the second SiC-MOSFET, during the dead time, to a second middle voltage that is higher than a second negative power supply voltage and lower than a second threshold voltage for the second SiC-MOSFET.

A miniature circuit breaker for providing short circuit and overload protection is disclosed herein. The miniature circuit breaker features a field effect transistor (FET), which may be a depletion mode metal oxide semiconductor FET (D MOSFET), a junction field-effect transistor (JFET), or a silicon carbide JFET, the FET being connected to a bi-metallic switch, where the bi-metallic switch acts as a temperature sensing circuit breaker. In combination, the D MOSFET and bi-metallic switch are able to limit current to downstream circuit components, thus protecting the components from damage.

Provided is a transistor drive circuit that drives a transistor to be driven and has a configuration including a controller that performs control to cause to temporally vary a circuit parameter contributing to a rise time or a fall time of the transistor to be driven.

An analog switch circuit includes: a switch unit and a control circuit, wherein the control circuit includes a sensor circuit and a gate-source voltage adjustment circuit. The switch unit operates a first switch therein according to a first gate-source voltage, to convert an input signal of an input terminal to an output signal of an output terminal. The sensor circuit is coupled between the input terminal and the output terminal, and generates a sensing signal according to a voltage difference between the input signal and the output signal. The gate-source voltage adjustment circuit is coupled to the sensor circuit, and adaptively adjusts the first gate-source voltage according to the sensing signal, to maintain the conduction resistance of the switch unit at a constant while the voltage difference changes.

A gate drive device drives a gate of a semiconductor switching element and controls a transient voltage corresponding to a voltage of a main terminal of the semiconductor switching element to a target value of the transient voltage at a time of switching the semiconductor switching element. The gate drive device includes a calculation circuit, a drive circuit, a detection circuit, and a learning circuit. The calculation circuit executes a predetermined calculation mode to calculate an operation amount for operating gate drive speed of the semiconductor switching element. The drive circuit drives the gate of the semiconductor switching element according to the operation amount. The detection circuit detects the transient voltage. The learning circuit executes learning processing to change the predetermined calculation mode based on the operation amount calculated by the calculation circuit and the transient voltage detected by the detection circuit.

A circuit includes first to third transistors. The first transistor includes a first terminal coupled to a first voltage, and a second terminal coupled to a connection. The second transistor includes a gate terminal coupled to the gate terminal of the first transistor, a first terminal coupled to a second voltage, and a second terminal coupled to the connection. The third transistor includes a first terminal coupled to the connection, a second terminal coupled to a node between the second terminals of the first and second transistors. The third transistor is controlled to be turned ON at a beginning of a first edge of a driving signal on the connection to pull a voltage of the driving signal on the first edge toward a threshold voltage, and be turned OFF in response to and after the voltage of the driving signal on the first edge reaching the threshold voltage.

The present disclosure concerns a circuit (302) for controlling two switches (210-1, 210-2) electrically in series, including sensors (310-1, 310-2) of voltages across the switches and a circuit (310) of comparison of signals output by said sensors, one at least of said sensors being an active circuit.

Multi-semiconductor SSPCs that solve bus level problems affecting systems as well as controller level problems affecting individual multi-semiconductor SSPCs are disclosed. Bus level and controller level problems adversely affect multi-semiconductor SSPCs and their associated systems. The disclosed multi-semiconductor SSPCs solve both bus level and controller level problems by implementing controlled rate-change of voltage (dv/dt) ramp-on rate, to ensure that the voltage on the input bus does not collapse when a multi-semiconductor SSPC is commanded closed and that a minimum amount of power is being dissipated evenly across the switching semiconductors.

A control circuit controls a switching element including a gate and a source corresponding to the gate. The control circuit includes an inductor, a circuit element, and a resistor. The inductor is connected between the gate and the source of the switching element. The circuit element is connected in series to the inductor between the gate and the source. The circuit element allows an electric current to flow therethrough in response to generation of electromotive force in the inductor. The resistor is connected in parallel to the inductor and the circuit element between the gate and the source.