An embodiment electronic circuit includes an electronic switch comprising a load path, and a control circuit configured to drive the electronic switch. The control circuit is configured to operate in one of a first operation mode and a second operation mode based at least on a level of a load current of the electronic switch. In the first operation mode the control circuit is configured to generate a first protection signal based on a current-time-characteristic of the load current and drive the electronic switch based on the first protection signal. The control circuit is configured to generate a status signal such that the status signal has a wakeup pulse when the operation mode changes from the second operation mode to the first operation mode and, after the wakeup pulse, a signal level representing a level of the load current.

A protection and attenuation circuit for sensitive AC loads is described. The circuit provides AC power protection and attenuation utilizing high-efficiency switch-mode techniques to attenuate an AC power signal by incorporating a bidirectional, transistorized switch driven from a pulse width modulation signal, PWM. The circuit monitors characteristics of the AC power signal driving a known load and characteristics of the load or other elements and determines the duty cycle of the pulse width modulated signal, PWM, based upon the duration and amplitude of the over-voltage, over-current, over-limit or other event.

A hot plug device includes an electronic subsystem and a plurality of main turn on FETs, wherein each main turn on FET includes a gate, a power input for coupling to a power source, and an output for controllably providing power to the electronic subsystem. An auxiliary current path is in parallel with the main turn on FETs and includes a fuse, an impedance element and an auxiliary turn on FET. A turn on controller controls the main turn on FETs and the auxiliary turn on FET. Current is initially through the high impedance auxiliary current path to apply voltage to an output power rail. Subsequently, current is allowed to pass through a plurality of main turn on FETs to the output power rail in response to the output power rail having a voltage exceeding a voltage threshold as a result of using the high impedance auxiliary current path.

A dynamic current limiter circuit is disclosed. The dynamic current limiter includes an input node an output node. The dynamic current limiter also includes a current control valve coupled between the input and output nodes, the current control valve being configured to limit current flow between the input and output nodes based on a control input. The dynamic current limiter also includes a current change detector coupled between the input and output nodes, the current change detector being configured to detect a change in current through the input and output nodes and generate a control signal configured to drive the control input. The current control valve is configured to limit current flow between the input and output nodes in response to the current control signal.

A fluid sample system includes a control system that operates in the hazardous area and controls one or more valves and optionally receives outputs from one or more transducers and optionally one or more sensors. The fluid sample system includes components that operate in a hazardous area and includes a control system that operates in the hazardous area and that controls one or more electrical devices. The control system communicates across a barrier with a system on a safe side of the barrier with as few as two intrinsically safe couplings including a single pneumatic coupling and a communication link coupling. The control system includes an intrinsically safe voltage boost circuit.

An input redundant circuit according to the present disclosure may include: a core power supply unit; a first input port connected to a first input voltage; a second input port connected to a second input voltage; a relay unit connected to the first input port and the second input port to supply one of the first input voltage and the second input voltage to the core power supply unit; and a surge current limiting unit coupled to the relay unit, configured to limit a surge current generated when the relay unit is switched between the first input voltage and the second input voltage.

A power switch module comprising a control component. Upon an indicated operating condition fulfilling a protection condition, the control component is arranged to transition the power switch module from an ON state to a latched-OFF state in which the control component is arranged to configure the switching device to be turned off to decouple the load node from the power supply node. Having transition to the latched-Off state, the control component is further arranged to determine whether a voltage level at the load node exceeds a threshold voltage level, and if it is determined that the voltage level at the load node exceeds the threshold voltage level, transition the power switch module from the latched-OFF state to a current-limited state in which the control component is arranged to control the switching device to limit current-flow there through.

A solid-state circuit breaker and breaking method are disclosed. In an embodiment, the solid-state circuit breaker includes a semiconductor switch; a controller, connected to the semiconductor switch; and an energy absorber, connected in parallel with the semiconductor switch. The controller is configured to obtain an equivalent inductance of a circuit of the solid-state circuit breaker upon a fault occurring in a line. Further, upon the equivalent inductance being greater than an inductance estimated value, the controller is configured to set a second current fault threshold. Finally, upon a fault current of the line reaching the second current fault threshold, the semiconductor switch is controlled to execute a closing operation.

A fault current limiter may include a current limiting leg to transmit a first current and a control leg in parallel with the current limiting leg, the control leg to transmit a second current. The control leg may include a plurality of solid state switches arranged in electrical series with one another; a plurality of current monitors arranged in electrical series with the plurality of solid state switches; and at least one triggering circuit, wherein the plurality of current monitors are electrically coupled to the at least one triggering circuit, and wherein the at least one triggering circuit is optically coupled to the plurality of solid state switches.

Provided is a sensor device wherein malfunction due to a negative surge is suppressed. This sensor device is provided with: a sensor element wherein electrical characteristics change corresponding to physical quantities; a signal processing circuit that processes output signals of the sensor element; a first transistor element that supplies currents to the sensor element and the signal processing circuit; a control circuit that controls a base current of the first transistor element; a power supply terminal; and a ground terminal. The sensor device is characterized in that the control circuit is provided with a limiting section that limits a current flowing from the ground terminal toward a base terminal of the first transistor element.