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.

A laser diode drive system configured to output a drive signal to control a voltage provided to a laser diode can include a circuit sensor system configured to output a sensed signal indicative of a drive current of a laser diode, and a temperature sensor configured to output a temperature signal indicative of a temperature of the laser diode or an ambient temperature of the laser diode. The system can include a temperature compensation system configured to output a correction signal based on the temperature signal to compensate for a temperature dependent factor in the sensed signal.

An apparatus to determine offset voltage to adjust a fuse current determination including a fuse load circuit structured to determine that no current is demanded for a fuse load, and to further determine that contactors associated with the fuse are open, an offset voltage determination circuit structured to determine an offset voltage corresponding to at least one component in a fuse circuit associated with the fuse, in response to the determining that no current is demanded for the fuse load, and an offset data management circuit structured to store the offset voltage, and to communicate a current calculation offset voltage for use by a controller to determine current flow through the fuse.

A circuit breaker comprises a solid-state bidirectional switch, a switch control circuit, current and voltage sensors, and a processor. The solid-state bidirectional switch is connected between a line input terminal and a load output terminal of the circuit breaker, and configured to be placed in a switched-on state and a switched-off state. The switch control circuit control operation of the bidirectional switch. The current sensor is configured to sense a magnitude of current flowing in an electrical path between the line input and load output terminals and generate a current sense signal. The voltage sensor is configured to sense a magnitude of voltage on the electrical path and generate a voltage sense signal. The processor is configured to process the current and voltage sense signals to determine operational status information of the circuit breaker, a fault event, and power usage information of a load connected to the load output terminal.

Provided by the present invention is a current overload protection apparatus. The apparatus comprises a current measuring device and a control module; the current measuring device is used to measure a current value on a current path; the control module is electrically connected to the current measuring device, and stores current threshold data; the current threshold data comprises a plurality of time intervals respectively corresponding to disconnection threshold values; the earlier the time corresponding to a plurality of time intervals, the larger the disconnection threshold value corresponding thereto; and the control module is used to receive and collect current signals within a specified time length so as to calculate the current value of the current path, and determine whether the current value is greater than or equal to the disconnection threshold values, and if so, then an overload protection step is performed to protect the load from current overload.

An overcurrent protection circuit limits a monitoring target current to or below a limit current value IOCP. For example, it can operate so as to give the limit current value IOCP, when temperature Tj is lower than a threshold value Tx, a flat temperature response and, when temperature Tj is higher than the threshold value Tx, a negative temperature response. For another example, it can operate so as to set the limit current value IOCP, when temperature Tj is lower than a threshold value Tx, at a first limit current value IOCP having a flat temperature response and, when temperature Tj is higher than the threshold value Tx, at a second limit current value IOCP having a flat temperature response and lower than the first limit current value IOCP.

An electrical circuit breaker system including an input terminal connecting an electrical current source and a plurality of output terminals for connecting electrical loads. Each output terminal includes an electrical switch and a current measuring unit. The circuit breaker system includes a current acquiring unit for acquiring current magnitudes measured at the output terminals and for determining a total current magnitude. A temperature acquiring unit acquires a temperature, and a computing unit is configured to determine a total current limit as a function of the acquired temperature. Further, a control unit is configured to select one of the plurality of output terminals based on a ranking of the output terminals and to interrupt the current supply at the selected output terminal by means of the corresponding electrical switch when the total current magnitude exceeds the determined total current limit.

A circuit breaker includes an electromechanical switch, a current sensor, a voltage sensor, and a processor. The electromechanical switch is serially connected between a line input terminal and a load output terminal of the circuit breaker, and configured to be placed in a switched-closed state or a switched-open state. The current sensor is configured to sense a magnitude of current flowing in a path between the line input and load output terminals and generate a current sense signal. The voltage sensor is configured to sense a magnitude of voltage at a point on the path between the line input and load output terminals and generate a voltage sense signal. The processor is configured to receive and process the current sense signal and the voltage sense signal to determine operational status information of the circuit breaker and determine power usage information of a load connected to the load output terminal.

Embodiments are directed to electronic fuse devices and systems. One such electronic fuse includes current sensing circuitry that senses a current in a conductor coupled between a power supply and a load, and generates a current sensing signal indicative of the sensed current. I2t circuitry receives the current sensing signal and determines whether the sensed current exceeds an I2t curve of the conductor. The electronic fuse further includes at least one of external MOSFET temperature sensing circuitry that senses a temperature of an external MOSFET coupled to the conductor, low current bypass circuitry that supplies a reduced current to the load in a low power consumption mode during which the external MOSFET is in a non-conductive state, or desaturation sensing circuitry that senses a drain-source voltage of the external MOSFET.

A circuit arrangement for protection against an undue overheating of a charging control, discharging control and/or a secondary battery is disclosed, the circuit arrangement comprising the secondary battery, the charging and/or discharging control for charging and/or discharging the secondary battery, a connector for connecting the charging and discharging control to an external power supply, at least one current limiting electronic component arranged in electrical connection to the charging and/or discharging control and optionally, a switchable load.