| 摘要 |
PROBLEM TO BE SOLVED: To obtain the more accurate, stabilized rotation of a motor without increasing the frequency of FG (rotational-speed information signal) pulses, which are the rotational-speed information of the motor to be controlled especially. SOLUTION: From the FG output (a) of an FG detector 12 for detecting the rotating information of a motor 11, a pulse signal (c) having the constant width in synchronization with the FG output (a) is formed with a comparator 13 and a one-shot multivibrator 14. The output (d) of a triangular wave generator 15, which is reset by the fall-down of the pulse signal (c), is held by a voltage holding circuit 16 in synchronization with the rise of the pulse signal (c). Then, of the holding voltage (e) and the output (d) of the triangular wave generator 15, the voltage at the higher level is selectively outputted by a multiplexer 19. The rotational speed of the motor 11 is controlled in accordance with the output (g). |
