| 摘要 |
PROBLEM TO BE SOLVED: To provide a reluctance sensor system measuring a motor driving speed with high accuracy even when the motor driving speed is low. SOLUTION: A sensor voltage signal is inputted into a peak hold circuit composed of an operational amplifier 3P, a diode 4P, and a capacitor 5P, to output a peak voltage signal. The sensor voltage signal is inputted into a bottom hold circuit composed of an operational amplifier 3B, a diode 4B, and a capacitor 5B, to output a bottom voltage signal. The peak voltage signal and the bottom voltage signal are inputted into a middle voltage signal generating circuit 6, to generate an intermediate voltage signal having an intermediate value between the peak voltage value and the bottom voltage value. Based on the size relation between the sensor voltage value and the intermediate voltage value, a comparator 7 generates an exact rectangular wave voltage signal whose duty ratio is 50%. The motor driving speed is thereby measured with high precision even if the motor driving speed is low. COPYRIGHT: (C)2009,JPO&INPIT
|
