| 摘要 |
PROBLEM TO BE SOLVED: To provide a signal amplification device for a phase detector for accurately detecting a rotation position of a rotor.SOLUTION: A signal amplification device for a phase detector, for detecting a rotation position based on a sensor signal having an amplitude level depending on a rotation position of a rotor of a motor, includes: first phase detecting means for detecting a phase by comparing a sensor signal with a predetermined threshold level, and outputting a first phase information signal indicating the detected phase; a phase counter for counting a phase count for calculating a signal amplification section of a sensor signal, based on the first phase information signal; amplitude detection means for detecting a peak level of a sensor signal, and outputting a result signal thereof; a signal gain calculation circuit for calculating signal gain for a sensor signal so that a peak level of a sensor signal indicated by the result signal becomes a predetermined amplitude level; signal gain control means for calculating a signal amplification section of a sensor signal based on the phase count, storing signal gain according to the signal amplification section, and outputting the signal gain; and signal amplification means for amplifying an amplitude level of a sensor signal based on the outputted signal gain. |
