JP2009254187A5 - - Google Patents

Claims (6)

The main power supply,
A circuit breaker connected between the main power source and the load;
Sub power supply,
A switching circuit formed by connecting four P-MOS semiconductor switches in series with each other and connected between the sub power source and a load;
Control means for controlling the opening / closing operation of the circuit breaker and the on / off operation of each semiconductor switch of the switching circuit;
Monitoring means for monitoring a source voltage of the semiconductor switch of the switching circuit and outputting a monitor signal to the control means;
Comprising a said control means, the breaker is closed, the power supply period to the load from the main power supply, performs the on-off operation of the semiconductor elements, and have groups Dzu the monitor signal from the monitor means, each A dual-system power supply device characterized by performing failure diagnosis of a semiconductor switch. 2. The dual power supply device according to claim 1, wherein a bias voltage is applied to drains of the four semiconductor switches by a bias voltage supply means, and the control means operates each of the semiconductor elements to turn on and off, and the monitoring means. by being monitored, and have groups Dzu the source voltage of each semiconductor switch, dual system power supply and performs a failure diagnosis of each of the semiconductor switches. In a double-system power supply device according to claim 2, wherein said bias voltage is connected between the main power or sub power supply, a point dividing the four semiconductor switches said connected in series to each other to One without two resistors A dual power supply device characterized by 3. The dual power supply device according to claim 2, wherein the semiconductor switches connected in series are connected in series in the order of a first semiconductor switch, a second semiconductor switch, a third semiconductor switch, and a fourth semiconductor switch, and the monitoring means. Is switch means that is turned on / off by the voltage levels of the source voltage between the first semiconductor switch and the second semiconductor switch and the source voltage between the third semiconductor switch and the fourth semiconductor switch, control means have group Dzu the off signal of the switch means, dual system power supply, characterized in that the failure diagnosis of each of the semiconductor switches.   3. The dual power supply apparatus according to claim 2, wherein the semiconductor switches connected in series are connected in series in the order of a first semiconductor switch, a second semiconductor switch, a third semiconductor switch, and a fourth semiconductor switch, and the monitoring means. Is a signal indicating a result of comparing the source voltage between the first and second semiconductor switches and the source voltage between the third and fourth semiconductor switches with a threshold value. Is output to the control means. In a double-system power supply device according to claim 1, wherein said dual system power supply, dual system power supply device characterized in that it is mounted on a vehicle.