| 摘要 |
PROBLEM TO BE SOLVED: To provide a current detector for controlling a vehicle running motor capable of dispensing with a high-accuracy power supply circuit, using a comparatively low-accuracy inexpensive power supply circuit and obtaining high- accuracy measurement results. SOLUTION: A power supply circuit 33 converts the input voltage of 12 V to voltage of 5 V and outputs the same to a current detector 125u for controlling a vehicle traveling motor. The voltage of 5 V is input to a current sensor 21. On detecting a current value of a current flowing through a conductor L, the current sensor 21 converts the detected current value to a voltage signal and outputs the same to an A/D converter 23. The A/D converter 23 converts the voltage input from the current sensor 21 to a digital value and output the same. In the thus constructed circuit, voltage is supplied to the current sensor 21 and the A/D converter 23 from the same power supply circuit 33, whereby even if the voltage Vs of the power supply circuit varies, the A/D converted value is not influenced by such variation. |
