A load driving method includes bringing an output transistor disposed between a first power supply line and an output terminal connected to a load into a conduction state by a protection transistor provided between a gate of the output transistor and a second power supply line when a polarity of a power supply coupled between the first power supply line and the second power supply lines is reversed, and forming a conductive path between the second power supply line and a back gate of the protection transistor via a transistor by a back gate control circuit when the polarity of the power supply is normal, the back gate control circuit including the transistor, a gate of the transistor being coupled to the first power supply line directly via a connection node located in a connecting line that couples the first power supply line and the output transistor, the transistor being coupled between the second power supply line and the back gate of the protection transistor.

A load driving device includes a lockout circuit unit (70) that, when a battery is connected in reverse to a drive circuit unit (10), autonomously decreases a gate-source voltage of an anti-reverse connection relay (41, 42) down to a voltage that interrupts conduction between a source electrode and a drain electrode.

A polarity reversal protection circuit includes a MOSFET and a turn-off circuit, which turns off the MOSFET in the case of a polarity reversal. The turn-off circuit includes a detector for detecting the case in which the voltage at the source terminal of the MOSFET undershoots the voltage at the drain terminal of said MOSFET. Furthermore, it includes a quick-break switch for turning off the MOSFET in the event of detected voltage undershooting, a comparator for comparing the voltages present at source terminal and drain terminal of the MOSFET after detected voltage undershooting, wherein the output of the comparator is connected to the gate terminal of the MOSFET, a boost converter, a buck converter and a charge pump for voltage supply, and a switch for switching off the comparator.

An electrical wiring device including a housing assembly including a plurality of terminals at least partially disposed therein, the plurality of terminals including a HOT/LOAD terminal, a NEUTRAL terminal, a first traveler terminal, and a second traveler terminal, wherein, when in use, at least one of the terminals is connected to line hot; a first series FET and a second series FET disposed in series between the HOT/LOAD terminal and one of the first traveler terminal or the second traveler terminal; at least one of a first sensor producing a first sensor output according to current flow or a voltage at the one of the first traveler terminal or the second traveler terminal and a second sensor producing a second sensor output according to current flow through the NEUTRAL terminal or according to a voltage between the first series FET and second series FET; and a controller configured to determine to which of the plurality of terminals line hot is connected based, at least, on the first sensor output or the second sensor output and to provide, during operation, at least one of a first control signal to the first series FET and a second control signal to the second series FET according to a user adjustable load setting.

A hybrid load protection apparatus (1) comprises a primary power supply path (1A) provided between an input terminal (2) and output terminals (2, 3) and a controllable mechanical switch (5A) connected in series with a primary coil (4A-1) coupled inductively to a secondary coil (4A-2) providing a voltage, U.sub.A, corresponding to a current rise speed of the electrical current flowing through the primary path (1A). The voltage, U.sub.A, is applied directly to a driver input (IN) of a first driver circuit (6A) to trigger automatically a switch-off of the mechanical switch (5A) within a first switch-off period (Δt1) to interrupt the primary power supply path (1A), A secondary power supply path (1B) is provided in parallel to the primary path (1A) and having a further coil (4B) connected in series with a semiconductor power switch (5B). wherein a second driver circuit (6B) associated with the secondary path (1B) detects an increasing electrical current, I, flowing through the secondary path (1B) caused by the interruption of the primary current path (1A) on the basis of a voltage drop (ΔU.sub.4) generated by the further coil (4B) and a non-linear voltage drop (ΔU.sub.5) along the semiconductor power switch (5B) applied as a sum voltage (U.sub.B) directly to a driver input (DESAT) at a high voltage side of the second analog driver circuit (6B) to trigger automatically a switch-off of the semiconductor power switch (5B) within a second switch-off period (Δt2) to interrupt the secondary power supply path (1B).

A multi-line supply unit for a vehicle control unit, including at least two supply lines each connected to a vehicle voltage source at the input and brought together at a common node at the output; and a protective device, including, in each of the supply lines, at least one first damping diode looped into the supply lines in the forward direction, between the vehicle voltage source and the node; and an operating method for such a multi-line supply unit. At least one switch element is looped into each of the supply lines, respectively, in parallel with the damping diode, respectively; an evaluation and control unit measuring and evaluating a line voltage at the inputs of the supply lines, respectively, and measuring and evaluating a reverse-polarity-protected supply voltage at the common node, and controlling the switch elements in the supply lines as a function of the evaluation, using corresponding control signals.

A reverse polarity protection circuit of a DC-DC converter includes an inductive component. When the DC-DC converter is connected to a power supply with correct polarity, the inductive component of the converter receives power via a body diode of a protection switch. Once the inductive component begins to charge and discharge under control of a driving switch, the protection switch turns on and allows full power to be provided to the inductive component. When the DC-DC converter is connected with reverse polarity, a clamping switch fed by the power supply turns on and connects a control input of the protection switch to ground, turning off the protection switch. The clamping switch is protected by a switch protection device to lower the voltage difference between a control input of the clamping switch and an input of the clamping switch.

A soft turn-off active clamp protection circuit and a power system are disclosed. The circuit includes a gate connection terminal, a drain connection terminal, a source connection terminal, a discharge capacitor, an overvoltage signal acquisition module, a negative feedback module, a discharge current control module and a turn-off control module.

A hybrid load protection apparatus (1) comprises a primary power supply path (1A) between input terminal and output terminals (2, 3) and a controllable mechanical switch (5A) connected in series with a primary coil (4A-1) coupled inductively to a secondary coil (4A-2) providing a voltage, U.sub.A, corresponding to a current rise speed of the electrical current flowing through the primary path (1A). The voltage, U.sub.A, is applied directly to a driver input (IN) of a first driver circuit (6A) to trigger automatically a switch-off of the mechanical switch (5A) within a first switch-off period (Δt1) to interrupt the primary power supply path (1A). A secondary power supply path (1B) is provided in parallel to the primary path (1A) and having a further coil (4B) connected in series with a semiconductor power switch (5B). wherein a second driver circuit (6B) associated with the secondary path (1B) detects an increasing electrical current, I, flowing through the secondary path (1B) caused by the interruption of the primary current path (1A) on the basis of a voltage drop (ΔU.sub.4) generated by the further coil (4B) and a non-linear voltage drop (ΔU.sub.5) along the semiconductor power switch (5B) applied as a sum voltage (U.sub.B) directly to a driver input (DESAT) at a high voltage side of the second analog driver circuit (6B) to trigger automatically a switch-off of the semiconductor power switch (5B) within a second switch-off period (Δt2) to interrupt the secondary power supply path (1B).

A direct current (DC)/DC conversion circuit includes an input end, a power circuit, and an output end, a bypass circuit that is a unidirectional conduction circuit, and a switch disposed between the input end and the power circuit, where the input end is configured to be coupled to an external power supply to receive power to the DC/DC conversion circuit. The bypass circuit is coupled between the input end and the power circuit, the bypass circuit is disposed between the switch and the power circuit, and the bypass circuit is coupled to the power circuit in parallel. The switch is configured to be closed when the input end is reversely coupled to the external power supply to enable a current from a positive electrode of the external power supply to flow back to a negative electrode of the external power supply through the bypass circuit and the switch.