| 摘要 |
PROBLEM TO BE SOLVED: To provide an electronic clock in which whether a rotor is turned or not can be detected in its early stages. SOLUTION: When driving pulses are supplied to a stepping motor 101 for chronograph-pointer drive from a drive circuit 102, the rotor 113 is turned, and an induced voltage is generated at a rotor driving coil 115 of a stepping motor 102 for hour-hand drive. A rotation detection circuit 109 outputs a rotation detection signal indicating that the rotor 113 is turned when zero-crossing points in the induced voltage within a driving-pulse supply period are the prescribed number or more. It outputs to a control circuit 107 a nonrotation detection signal indicating a nonrotation when the zero-crossing points do not reach the prescribed number or within a prescribed time. The control circuit 107 receives the nonrotation detection signal from the detection circuit 109, and it controls the drive circuit 103 so as to redrive the motor 101 by high-energy driving pulses. COPYRIGHT: (C)2004,JPO |
