| 摘要 |
PURPOSE:To detect revolutions at optimum timings by detecting revolutions and nonrevolutions by plural kinds of revolution detection signals corresponding to main driving signals in an electronic timepiece provided with the plural main driving signals driving a step motor. CONSTITUTION:A main driving pulse generating circuit 21 driving a step motor generates 6 kinds of main driving pulses, 2.44, 2.68, 2.92, 3.16, 3.40, 3.66ms by the bit outputs of a hexad up/down counter 20. A revolution detection signal generating circuit 22 generates 3 kinds of revolution detection signals by the bit outputs of the counter 20. The timings of revolution detection are slow when the pulse width of the main driving pulses is narrow and fast when the pulse width is wide. Hence, the timings of the revolution detection are optimum and the electric power consumption for the purpose of detection decreases. |
