Patent ID: 8717037

Claim:
An electronic control device, comprising: an analog-to-digital converter which receives as inputs: a reference voltage for analog-to-digital conversion output from a first controlled voltage source, a voltage for abnormality determination output from a second controlled voltage source independent of the first voltage source and has a voltage value lower than the reference voltage, and a control signal being an analog signal from an external detection source, and which converts the control signal and the voltage for abnormality determination into digital data by using the reference voltage; a processor configured to perform a control operation for a predetermined control subject by using the digital data of the control signal that is input from the analog-to-digital converter; and an abnormality determiner configured to monitor the voltage value of the voltage for abnormality determination based on the digital data input from the analog-to-digital converter to perform abnormality determination for the analog-to-digital converter and the reference voltage, and configured to determine that one of the analog-to-digital converter and the reference voltage is abnormal when the voltage value of the voltage for abnormality determination falls out of a predetermined normal range, wherein the reference voltage derives voltage from an external power source and is subject to fluctuations of the voltage output from the external power source, and wherein the voltage for the abnormality determination derives voltage from the external power source and is not subject to the fluctuations of the reference voltage.