| 摘要 |
PURPOSE:To decrease the power loss when a plurality of stepping motors, which are not driven at the same time normally, are simultaneously driven with the current less than the current in normal driving at the number of rotation lower than that in normal driving. CONSTITUTION:A frequency dividing circuit 14 sends a divided clock signal 15, which is obtained by dividing a clock signal 13, into a driving-motor selecting circuit 73. The driving-motor selecting circuit 73 generates motor-phase switching instruction signals 76 and 77 and motor-driving allowance signals 74 and 75 by the divided clock signal 15 and motor-driving command signals 10 and 30. When a motor I1 and a motor II 21 are driven at the same time, the driving-motor selecting circuit 73 divides the divided clock signal 15 into two parts and outputs the signals as the motor-phase switching instruction signals 76 and 77. At the same time, the circuit 73 alternately switches the motor-driving allowance signal 74 and the motor-driving allowance signal 75 at the half period of the period of the divided clock signal 15 and obtains the low level. |
