Abstract: An increase in the capacity of a power storage unit is effectively suppressed. An in-vehicle backup power source control apparatus includes a discharge unit, a control unit, and a temperature obtaining unit. The control unit controls a discharge operation such that an output voltage of the discharge unit reaches a target voltage. The temperature obtaining unit obtains the temperature of a power storage unit. When the temperature obtained by the temperature obtaining unit is within a predetermined first temperature range, the control unit sets the target voltage to a first target voltage, and when the temperature obtained by the temperature obtaining unit is within a predetermined second temperature range that is higher than the first temperature range, the control unit sets the target voltage to a second target voltage that is higher than first target voltage.

Abstract: Provided is a configuration that can detect the internal resistance of a power storage unit. An internal resistance detection device includes a DC-DC converter that is configured to raise the output voltage to a target voltage by performing constant current operation in which the charging current is output at a target charging current, and, when the output voltage reaches the target voltage, to control power such that the charging current is lowered by performing constant voltage operation in which the output voltage is fixed at the target voltage. A control unit detects the internal resistance of a power storage unit based on a target charging current Ichg during constant current operation by the DC-DC converter, a drop time, which is the time that passes from when constant voltage operation starts to when the charging current drops to a predetermined current value, and a capacity of the power storage unit.

Abstract: A configuration with which, even if the supply of power from a power supply portion ceases, the power from another power supply source can be instantly supplied to a power supply target is more easily achieved. In a backup circuit, a control unit causes a second voltage conversion portion to perform a voltage conversion operation in response to satisfaction of a predetermined first backup condition, and a power supply portion-side conductive path and an electricity storage portion-side conductive path are electrically connected to each other via a resistive portion when the control unit is causing the second voltage conversion portion to perform the voltage conversion operation. Furthermore, the control unit causes the first voltage conversion portion to perform a second operation in response to a predetermined second backup condition being satisfied when the control unit is causing the second voltage conversion portion to perform the voltage conversion operation.

Abstract: A configuration can be more easily realized in which the temperature of an auxiliary power source can be increased even in a low temperature environment. In the in-vehicle auxiliary power source control device, a control unit performs a charging operation of switching a first switch on and switching a second switch off, and a discharging operation of switching the first switch off and switching the second switch on. Also, the temperature of an auxiliary power source is raised by heat generated by a resistor unit due to the charging operation and the discharging operation performed by the control unit.

Abstract: A power supply control apparatus includes: a semiconductor switching element switched with PWM control; a PWM signal output unit outputting a PWM signal; a current circuit outputting a current related to a current flowing through the semiconductor switching element; a filter circuit converting the current that is output from the current circuit to a voltage; an overcurrent protection circuit turning off the semiconductor switching element based on a voltage value of the voltage filtered by the filter circuit; a voltage detection unit detecting the voltage value of the voltage at a timing near an end of a pulse of a PWM signal; a temperature estimation unit estimating, a temperature of an electric wire through which a current flows that also flows through the semiconductor switching element; and an electric wire protection unit turning off the semiconductor switching element based on the temperature estimated by the temperature estimation unit.

Abstract: In a voltage detection circuit, if a driving signal is provided from a control circuit to a drive target circuit that is one of a plurality of individual detection circuits, and a non-driving signal is provided from the control circuit to the other non-target circuits, switch portions of the non-target circuits are turned off to prevent a current from flowing through first transistors and second transistors of the non-target circuits, whereby generation of the output voltages in the non-target circuits is stopped, and a switch portion of the drive target circuit is turned on so as to allow a current to flow through a first transistor and a second transistor of the drive target circuit, whereby a voltage according to a voltage across both ends of an electricity storage cell corresponding to the drive target circuit is applied to an output conductive path.

Abstract: A power supply control device prevents an electrical wire and a switch element from smoking. The power supply control device includes a switch element provided at a midpoint in an electrical wire that connects a power supply and a load. A current detection unit detects the current value of current flowing in the electrical wire. A temperature estimation unit estimates the wire temperature of the electrical wire based on the current value detected by the current detection unit. A control unit turns on or off the switch element based on the wire temperature estimated. The control unit estimates the smoking temperature of the switch element by changing the heat dissipation time constant of the electrical wire used in temperature calculation to a smaller value, and turns off the switch element if the wire temperature is greater than or equal to the estimated smoking temperature of the switch element.

Abstract: A power supply control device includes a switch disposed in a first current path of a current flowing from a battery. A first comparator compares a voltage value of a current input end of the switch to which the current is inputted with a voltage threshold. When the voltage value of the current input end is less than the voltage threshold, a drive circuit turns off the switch. The battery supplies, via a second current path, power to a starter that starts an engine of a vehicle. The voltage threshold is less than the voltage value of the current input end of the switch in the case where the battery supplies the power to the starter.

Abstract: A control circuit turns ON or OFF a switch that is provided at a midpoint of a wire. Thus, power supply via the wire is controlled. A current output circuit outputs a current that corresponds to a current flowing through the wire to a resistance circuit. In the resistance circuit, a series circuit of a resistor (R2) and a capacitor (C1) is connected in parallel to a resistor (R1). The control circuit) turns OFF the switch if the end-to-end voltage value of a voltage across both ends of the resistance circuit is larger than or equal to a reference voltage value.

Abstract: It is an object of the present disclosure to reduce the number of constituent components and accurately detect a current. A current detection circuit detects a current flowing through a DC/DC converter. A first output unit applies, to a third signal path, a voltage that corresponds to an output from a detection sensor, which has detected a larger current, out of a first sensor and a second sensor. Furthermore, the first output unit applies, to the third signal path, a voltage obtained by reflecting a voltage drop at the transistor or the transistor that is connected to the detection sensor, in the voltage output from the detection sensor. A second output unit applies, to a fourth signal path, a voltage obtained by reflecting a voltage drop that occurs between a base and an emitter of a transistor, in the voltage applied to the third signal path.

Abstract: A power supply control apparatus that includes a switching circuit that turns ON or OFF a switch provided at a point along a wire, wherein power supply via the wire is controlled by switching with the switching circuit; a current output circuit configured to output a current whose current value increases as a current value of a current flowing through the wire increases; a resistance circuit through which the current that the current output circuit outputs flows, wherein the resistance circuit includes: a first resistor; and a series circuit of a second resistor and a capacitor that is connected in parallel to the first resistor; and a voltage applying circuit configured to, if an end-to-end voltage value across the resistance circuit becomes higher than or equal to a predetermined voltage value, apply a voltage whose value is higher than the predetermined voltage value.

Abstract: A power supply control device that includes a switch control unit that is configured to switch on and off a first switch and a second switch and receive a supply of power from a battery, the first switch and the second switch being respectively provided in a plurality of power supply paths through which power is supplied from one end of a battery to one end of a first load and one end of a second load; an output terminal from which current that flows from the battery via the switch control unit is output; a diode whose anode is connected to the output terminal, and whose cathode is connected to one end of the second load; an opening detection circuit; and a voltage detection circuit.

Abstract: If a main switch and a sub-switch are OFF and ON respectively, a comparator compares a source voltage value of the main switch to an output voltage value of a direct-current power source. In the same case, the comparator compares an end-to-end voltage value between a source and a drain of the main switch to a threshold value. A voltage value of the voltage applied to one end of the sub-switch is lower than the voltage value at the drain of the main switch. The output voltage value of the direct-current power source is lower than the voltage value. The threshold value is lower than the difference between the voltage value at the drain of the main switch and the voltage.

Abstract: An in-vehicle determination has a current generation circuit and a comparison circuit. The current generation circuit is provided with a second resistance unit electrically connected on one end side to a second reference conduction path that is set to a second reference potential that is higher than a first reference potential of a first reference conduction path, and allows a current that depends on the current flowing through a first resistance unit to flow to the second resistance unit from the second reference conduction path side. The comparison circuit outputs a first signal in the case where the potential of the other end of the second resistance unit is smaller than a threshold potential that is generated with reference to the second reference potential, and outputs a second signal in the case where the potential of the other end of the second resistance unit is larger than the threshold potential.

Abstract: A power supply control device and a power supply control method capable of detecting a switch-related failure properly are provided. A power supply control device controls power supply via a switch. An output unit of a microcomputer produces a switching signal that instructs the switch to turn alternately on and off. A detection circuit reports a failure related to the switch if an accumulated period has reached or exceeded a threshold period. The accumulated period is accumulation of one or more periods when the switching signal instructs the switch to turn on but a comparator does not detect an on-state of the switch.

Abstract: In a power supply control device, a microcomputer controls the supply of power from a battery to loads via a battery conductor by individually switching on and off switches. While power is being supplied from the battery to the microcomputer, current flows from the positive electrode of the battery to a battery terminal, the battery conductor, a diode, a resistor, a regulator, the microcomputer, an intermediate conductor, a fuse portion, a GND conductor, and a GND terminal in this order. If a current greater than or equal to a predetermined current flows to the fuse portion, the fuse portion breaks.

Abstract: In a power supply control apparatus, if a switching signal input from a microcomputer to a control circuit instructs switching on of a semiconductor switch, when an input voltage that is input to the drain of the semiconductor switch is higher than or equal to a predetermined voltage, the control circuit drives a charging circuit. The charging circuit charges a capacitor (Cs) via a diode (D1). Accordingly, a voltage at the gate of the semiconductor switch taking a potential at the source of the semiconductor switch as a reference becomes higher than or equal to a predetermined voltage, and thus the semiconductor switch is switched on. While driving the charging circuit, the control circuit keeps driving the charging circuit even if the input voltage becomes lower than the predetermined voltage.

Abstract: It is an object of the present disclosure to reduce the number of constituent components and accurately detect a current. A current detection circuit detects a current flowing through a DC/DC converter. A first output unit applies, to a third signal path, a voltage that corresponds to an output from a detection sensor, which has detected a larger current, out of a first sensor and a second sensor. Furthermore, the first output unit applies, to the third signal path, a voltage obtained by reflecting a voltage drop at the transistor or the transistor that is connected to the detection sensor, in the voltage output from the detection sensor. A second output unit applies, to a fourth signal path, a voltage obtained by reflecting a voltage drop that occurs between a base and an emitter of a transistor, in the voltage applied to the third signal path.

Abstract: An electric wire protection device comprising a pyrotechnic cutoff switch disposed between an electric wire connecting a load and a vehicle-mounted power supply that is connected to a reference potential. The pyrotechnic cutoff switch is disposed between the electric wire and has: a conductive part through which current between the vehicle-mounted power supply and the load flows; a cutting blade cuts the conductive part; a drive part, actuated by gunpowder, propels the cutting blade in a direction in which the conductive part is to be cut; and first and second terminals that input and output current that drives the drive part. In addition, the electric wire protection device comprises: a conductive wire having one end thereof connected to the electric wire and the other end thereof connected to the first terminal; and a diode having an anode connected to the reference potential and a cathode connected to the second terminal.

Abstract: A relay control device is provided configured to reduce the amount of power supplied to a coil in an electromagnetic relay. The relay control device includes a control unit for generating and outputting a PFM signal to control the voltage-drop DC/DC converter unit, a filter unit allowing passage of the PFM signal, and a circuit unit controlling the operation of the voltage-drop DC/DC converter unit in accordance with the output signal of the filter unit. If the filter unit does not allow passage of the PFM signal, the circuit unit prevents the voltage-drop DC/DC converter unit from dropping the voltage, and performs control so as to output the power supply voltage to a coil in the electromagnetic relay. If the filter unit prevents the PFM signal from passing, a current path from a power supply potential to a ground potential within a circuit unit is cut off by transistors.