Abstract: A DC-DC converter includes a protection function for handling a reverse connection state, and a protection function for handling a predetermined abnormality other than a reverse connection state, while reducing conduction loss. The DC-DC converter includes a first protection circuit unit, and a switching element on a first conductive path of a high-voltage side switches to an OFF state upon a predetermined abnormal state being detected to prevent a current from flowing into a voltage conversion unit. Furthermore, a reverse connection protection circuit unit and a switching element, on a third conductive path between the voltage conversion unit and a reference conductive path, is configured to switch to an off state if at least a low-voltage side power supply unit is in a reverse connection state, preventing a current from the reference conductive path. Thus, a current is prevented from flowing toward a power supply that is improperly connected.

Abstract: The present invention realizes a DC-DC converter that is provided with a reverse flow protection function, while reducing conduction loss. A DC-DC converter includes: a voltage conversion unit that steps down a voltage applied to a first conductive path and output the resulting voltage to a second conductive path; a reverse flow state detection unit that detects a reverse flow state of a current flowing through the second conductive path; and a reverse protection control unit that performs a protecting operation when a current flows in a reverse direction. A switching element is provided on a third conductive path that is located between a voltage conversion unit and a reference conductive path, and the reverse protection control unit operates to switch the switching element to an OFF state upon a reverse flow state being detected.

Abstract: A configuration is realized that enables ON/OFF operations to be performed stably and is unlikely to increase the switching time when driving an in-vehicle semiconductor switching device. An in-vehicle semiconductor switching device is turned ON and OFF by an ON signal and an OFF signal that are output from an in-vehicle driving circuit, and is switched between an ON state and an OFF state, at a position between a first conducting path and a second conducting path. Only some of a plurality of second terminals, which are electrically connected to a second semiconductor portion of a semiconductor switching element, are coupled to the second conducting path, and at least one of the remaining second terminals is coupled to a driving circuit-side conducting path (a conducting path electrically connected to the driving circuit.

Abstract: A control portion and semiconductor switches included in a power supply system function as a current control device. The source of the semiconductor switch is connected to the source of the semiconductor switch. The two semiconductor switches connect the respective positive electrodes of a first power storage element and a second power storage element to each other. The control portion controls a current flowing between the drains of the two semiconductor switches by substantially simultaneously turning on or off the two semiconductor switches. The respective breakdown voltages between the drain and the source of the two semiconductor switches are different from each other.

Abstract: The present invention realizes a DC-DC converter that is provided with a reverse flow protection function, while reducing conduction loss. A DC-DC converter includes: a voltage conversion unit that steps down a voltage applied to a first conductive path and output the resulting voltage to a second conductive path; a reverse flow state detection unit that detects a reverse flow state of a current flowing through the second conductive path; and a reverse protection control unit that performs a protecting operation when a current flows in a reverse direction. A switching element is provided on a third conductive path that is located between a voltage conversion unit and a reference conductive path, and the reverse protection control unit operates to switch the switching element to an OFF state upon a reverse flow state being detected.

Abstract: A DC-DC converter includes a protection function for handling a reverse connection state, and a protection function for handling a predetermined abnormality other than a reverse connection state, while reducing conduction loss. The DC-DC converter includes a first protection circuit unit, and a switching element on a first conductive path of a high-voltage side switches to an OFF state upon a predetermined abnormal state being detected to prevent a current from flowing into a voltage conversion unit. Furthermore, a reverse connection protection circuit unit and a switching element, on a third conductive path between the voltage conversion unit and a reference conductive path, is configured to switch to an off state if at least a low-voltage side power supply unit is in a reverse connection state, preventing a current from the reference conductive path. Thus, a current is prevented from flowing toward a power supply that is improperly connected.

Abstract: A control portion and semiconductor switches included in a power supply system function as a current control device. The source of the semiconductor switch is connected to the source of the semiconductor switch. The two semiconductor switches connect the respective positive electrodes of a first power storage element and a second power storage element to each other. The control portion controls a current flowing between the drains of the two semiconductor switches by substantially simultaneously turning on or off the two semiconductor switches. The respective breakdown voltages between the drain and the source of the two semiconductor switches are different from each other.