| 摘要 |
PURPOSE:To shorten time until servolock of motor rotation phase and to diminish dispersion in time by controlling the gain of rotation phase control signals according to the error between rotation phase detection signal and phase reference signal. CONSTITUTION:An exclusive OR gate 22 that is a phase difference detection means detects the error (phase difference) between rotation phase detection signal SWP and phase reference signal RP. Resistors R2, R3 and an analog switch 25 that are variable gain means control the gain of rotation phase control signal according to detection output from the phase difference detection means 22. Hereupon phase difference detection and gain control in the phase difference detection means 22 and variable gain means R2, R3, 25 are attained when the rotation speed servo locks but the rotation phase servo does not lock. This process can shorten time until the servolock of motor rotation and further diminish dispersion in time until servolock of rotation phase. |
