| 摘要 |
PURPOSE:To suppress an impact noise of a step motor by pulse-modulating the former half of a driving pulse for the step motor and by increasing the width of the modulated pulse in sequence. CONSTITUTION:Driving pulses 100 and 102 for step motor 26, outputted from AND gates 36 and 40, are mixed with a pulse train of 512Hz from frequency dividing circuit 20 by AND gates 38 and 42, whose outputs are inputted to clock inputs of 32mol address counters 28 and 30. Outputs of address counters 28 and 30 are read by ROMs 32 and 34 stored with programs that increase gradually modulated pulse width from the rise of driving pulses, thereby driving step motor 26 through driving circuit 24. |
