Abstract: A device capable of switching the supply source to a power storage unit without interrupting power supply to a power supply target even in the case where power supply from a power source unit cuts out is realized with a simple configuration. A backup device includes a discharging circuit that steps up or steps down a voltage applied to a power storage unit-side conduction path and applies the resulting voltage to an output-side conduction path, a control unit (5) that controls the discharging circuit to apply, to the output-side conduction path, a predetermined target voltage that is lower than a voltage that is applied to a power path in the case where a power source unit is fully charged, and a diode (element unit) that is provided between the power path and the output-side conduction path.

Abstract: A power source device, capable of charging a power storage device using power from a power source, is realized with a configuration capable of suppressing the generation of heat and noise. The power source includes a controller that determines an output state of a power storage device on the basis of a detection value detected by a voltage detection circuit. When the output state of the power storage device corresponds to a prescribed high-voltage state when prescribed charging conditions are satisfied, the controller causes only a first charging circuit, among the first charging circuit and a second charging circuit, to operate. When the output state corresponds to a prescribed low-voltage state, the controller causes only the second charging circuit to operate.

Abstract: A device capable of switching the supply source to a power storage unit without interrupting power supply to a power supply target even in the case where power supply from a power source unit cuts out is realized with a simple configuration. A backup device includes a discharging circuit that steps up or steps down a voltage applied to a power storage unit-side conduction path and applies the resulting voltage to an output-side conduction path, a control unit (5) that controls the discharging circuit to apply, to the output-side conduction path, a predetermined target voltage that is lower than a voltage that is applied to a power path in the case where a power source unit is fully charged, and a diode (element unit) that is provided between the power path and the output-side conduction path.

Abstract: The present invention realizes a power supply device that can, even if an abnormality occurs in a power supply unit, block a current from flowing into the path from the other power supply unit.

Abstract: The present invention realizes a power supply device that can, even if an abnormality occurs in a power supply unit, block a current from flowing into the path from the other power supply unit.

Abstract: A device is realized, with a simpler configuration, that is capable of switching a supply source to a power storage device without interrupting power supply to a recipient of power even if the power supply from a main power source is shut off. Provided is a wiring section to which a voltage is applied based on the output from the main power source in a normal condition; a wiring section provided between a power storage device and the wiring section; and a diode provided between the two wiring sections. The diode restricts the flow of current between the wiring sections when the voltage of the battery wiring section is smaller than the voltage of the main wiring section and allows the flow of current from the battery wiring section to the main wiring section when the voltage of the battery wiring section is greater.

Abstract: A power source device, capable of charging a power storage device using power from a power source, is realized with a configuration capable of suppressing the generation of heat and noise. The power source includes a controller that determines an output state of a power storage device on the basis of a detection value detected by a voltage detection circuit. When the output state of the power storage device corresponds to a prescribed high-voltage state when prescribed charging conditions are satisfied, the controller causes only a first charging circuit, among the first charging circuit and a second charging circuit, to operate. When the output state corresponds to a prescribed low-voltage state, the controller causes only the second charging circuit to operate.