| 摘要 |
PURPOSE:To achieve a lowering of average power consumption of a motor, by making a signal time range of a second motor drive signal larger than a first drive signal time range to prevent malfunctioning with the lowering of a voltage across a charge accumulating means. CONSTITUTION:An electromotive force generated with a power generating means 101 is accumulated by a second charge accumulating means 104 through a first charge accumulating means 103 and an N-channel MOS transistor 106. A time counting circuit 102 which counts time, controls the transistor 106, drives a motor 105 for a time display pointer is put into operation by the means 104. Then, the first motor drive pulse width P1 is made smaller than the subsequent motor drive pulse width P2 to reduce potential changes in a voltage VSS at a terminal 108 of the means 104. This enables accurate driving of a motor even when a first motor drive signal is outputted and a second motor drive signal is outputted before a voltage across the charge accumulating means is restored sufficiently. This also allows a shorter signal range of the first motor drive signal thereby lowering drive consumption power of the motor.
|
