Control unit for vehicle

摘要

In a control unit for a vehicle, a redundancy circuit includes a main power source line, a back-up power source line, and a diode. The back-up power source line performs a voltage compensation operation when a voltage of the main power source line is lower than a predetermined voltage. The back-up power source line is turned on when a predetermined period of time has elapsed after the main power source line is turned on. The back-up power source line is turned off when a predetermined period of time has elapsed after the main power source line is turned off. The diode is disposed on the back-up power source line. The fault detector detects an open fault of the diode when a voltage of a cathode of the diode is lower than a predetermined threshold within the predetermined period of time after the main power source line is turned off.

主权项

1. A control unit for a vehicle, comprising:
a redundancy circuit including:
a main power source line being supplied with electric power from a battery of the vehicle;a back-up power source line performing a voltage compensation operation when a voltage of the main power source line is lower than a predetermined voltage, the back-up power source line being turned on when a predetermined period of time has elapsed after the main power source line is turned on, and the back-up power source line being turned off when a predetermined period of time has elapsed after the main power source line is turned off; anda diode being disposed on the back-up power source line; and a fault detector monitoring a voltage of an anode of the diode and a voltage of a cathode of the diode; and an energy reserve capacitor supplying electric power to the fault detector until the predetermined period of time elapses after the main power source line is turned off, wherein: the fault detector detects an open fault of the diode when the voltage of the cathode of the diode is lower than a predetermined threshold within the predetermined period of time after the main power source line is turned off, and the predetermined threshold is less than or equal to a value that is obtained by subtracting a voltage drop of the diode in a forward direction from the voltage of the anode of the diode, and is larger than the voltage drop of the diode in the forward direction.