| 摘要 |
PROBLEM TO BE SOLVED: To provide a technique for an electric power unit in which a common power supply circuit supplies electric power to a main microcomputer and a sensor, the technique being configured to securely supply power to the main microcomputer even in a case where a power failure occurred between the main microcomputer/the sensor and the common power supply circuit.SOLUTION: A common power supply circuit 6 supplies electric power to a main microcomputer 11 and a sensor 15. A monitoring microcomputer 12 acquires an output voltage of the common power supply circuit 6. A first switching circuit 9 connects or disconnects the common power supply circuit 6 with or from the main microcomputer 11 and the sensor 15. A second switching circuit 10 connects or disconnects the main microcomputer 11 with or from a communication power supply circuit 7. If the monitoring microcomputer 12 detects on the basis of the results it has acquired, that any abnormality occurred in the system of the common power supply circuit 6, the first switching circuit 9 disconnects the common power supply circuit 6 from the main microcomputer 11 and the sensor 15, and the second switching circuit 10 connects the main microcomputer 11 with the communication power supply circuit 7.SELECTED DRAWING: Figure 1 |
