| 摘要 |
PURPOSE:To prevent a fine potential difference from being generated between ground points and to preclude malfunction by using the same driving voltage for a CPU and a sensor circuit and making the ground lines of the CPU, its power source, and sensor circuit in common to one another. CONSTITUTION:The CPU 3 of a sensor signal processing circuit 30 and the sensor circuit 1 are driven by a 5V power source 2 and the CPU 3, power source 2, and sensor circuit 1 are connected to the common ground line 4 and grounded. Further, a driving control circuit 40 is constituted of a motor M and a power source 11 and connected to the common ground line. There is the possibility that the detection signal of the sensor circuit 1 varies or the reference voltage of plural stages of an A/D converting circuit incorporated in the CPU 3 varies to generate a read error or malfunction of the A/D converting circuit, but they are grounded in common as mentioned above to eliminate a fine potential difference between the ground points and also preclude the malfunction. |
