| 摘要 |
PURPOSE:To always follow to the variation in the bias voltage of a motor by adding a loop for feeding back the displacement of a period of a frequency signal in response to the rotating speed of a motor from a reference value. CONSTITUTION:A frequency signal FG from a frequency generator 2 is converted by a digital delay circuit 11 into a signal FD, and a digital trap 12 outputs a digital signal of a trapezoidal signal to gradually rise a voltage from when the signal FG falls. A latch circuit 13 latches the output by the rise of the signal FG. A comparator 17 outputs a bias voltage in response to the difference between the speed servo error voltage latched in the circuit 13 and a reference signal REF. A mixer amplifier 15 supplies to a motor 1 by adding a bias voltage to the speed servo error voltage. |
