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: Provided is a control device that stops the power supply when the first FET is short-circuited. In the control device, a boost circuit increases the voltage of one end of a resistor on the boost circuit side to a predetermined voltage that is higher than the source voltage of the first FET. An AND circuit instructs the discharge circuit to decrease the voltage at the other end of the resistor when the voltage at the other end of the resistor is less than a threshold voltage if the AND circuit instructs the boost circuit to increase the voltage at the one end of the resistor on the boost circuit side. The threshold voltage exceeds the voltage at the one end of the resistor if the voltage at the one end of the resistor on the boost circuit is the predetermined voltage and if the first FET is short-circuited.

Abstract: A control device includes a first series circuit and a second series circuit. In the first series circuit, a first switch and a first resistor are connected in series to each other. In the second series circuit, a second switch and a second resistor are connected in series to each other. A current detection circuit outputs a voltage value that corresponds to a voltage value between two ends of the first resistor. When an instruction to turn on the first switch and the second switch has been given, a control unit senses any occurrence of a failure in at least one of the first switch, the second switch, the first resistor, and the second resistor, based on the voltage value output by the current detection circuit.

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: 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: 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: 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 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: In a power supply control apparatus, when a semiconductor switch is switched ON, a charging circuit increases a base voltage. A first switch is ON if a differential voltage obtained by subtracting a gate voltage from a base voltage is at least a first reference voltage, and is OFF if the differential voltage is smaller than the first reference voltage. If the first switch is ON, a battery or a capacitor charges parasitic capacitors of the semiconductor switch.

Abstract: Provided is a control device that stops the power supply when the first FET is short-circuited. In the control device, a boost circuit increases the voltage of one end of a resistor on the boost circuit side to a predetermined voltage that is higher than the source voltage of the first FET. An AND circuit instructs the discharge circuit to decrease the voltage at the other end of the resistor when the voltage at the other end of the resistor is less than a threshold voltage if the AND circuit instructs the boost circuit to increase the voltage at the one end of the resistor on the boost circuit side. The threshold voltage exceeds the voltage at the one end of the resistor if the voltage at the one end of the resistor on the boost circuit is the predetermined voltage and if the first FET is short-circuited.

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: A power supply control device controls power supply via a switch by causing a drive circuit to turn on and off the switch. A first resistance is disposed on a path of a current flowing via the switch. A differential amplifier outputs a voltage corresponding to a value of a voltage between two ends of the first resistance. A first capacitor is connected between a point midway on a path of power supply to the differential amplifier and an upstream end of the first resistance. A second capacitor is connected between a point midway on the path of power supply and a downstream end of the first resistance.

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: 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: In a power supply control apparatus, when a semiconductor switch is switched ON, a charging circuit increases a base voltage. A first switch is ON if a differential voltage obtained by subtracting a gate voltage from a base voltage is at least a first reference voltage, and is OFF if the differential voltage is smaller than the first reference voltage. If the first switch is ON, a battery or a capacitor charges parasitic capacitors of the semiconductor switch.

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: Provided is a power supply control apparatus, a power supply control method, and a computer program that can prevent an extremely large current from flowing via a switch. A power supply control apparatus is configured to control power supply via a switch. A control unit is configured to determine whether to switch ON a semiconductor switch. If the control unit determines to switch ON the switch, when a voltage value at a current input terminal of the switch, to which a current is input, is lower than a predetermined voltage value, a driving circuit is configured to switch ON the switch.

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 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.