Patent ID: 9601927
Date: 2017-03-21
CPC Classifications: G06F,H02J

Claim:
1. An electronic control device, comprising: a constant-voltage power supply including a constant-voltage control circuit portion; and a main control circuit portion including a multi-channel A-to-D converter, a micro-processor, a program memory, and a RAM memory cooperate to drive an electronic load group under control in response to an operation condition of a switch sensor group and an analog sensor group, wherein: the constant-voltage power supply is fed an input power-supply voltage from a power supply outside the electronic control device, and the constant-voltage control circuit portion operates to distribute and feed or divide and feed a first output voltage to the multi-channel A-to-D converter, and the first output voltage having a highest degree of accuracy among the first and second output voltages, or a second output voltage to the RAM memory, and wherein: the multi-channel A-to-D converter generates a digital output in proportion to a ratio of a reference voltage applied to a reference voltage terminal and an input signal voltage and, when the ratio is 1, the multi-channel A-to-D converter generates a maximum digital output, 2 calculating a maximum deviation by periodically inputting a digital conversion value of the smoothed power-supply monitor signal or the unsmoothed power-supply monitor signal or the unsmoothed power-supply monitor signal into a shift register formed of the RAM memory, and determining an abnormality in the constant-voltage power supply in a case where the calculated maximum deviation exceeds a predetermined threshold value, wherein the maximum deviation is a deviation between a maximum value and a minimum value of a latest predetermined number of digital conversion values.