| 摘要 |
Provided is an electronic clock which makes no erroneous determination of rotation detection and suppresses unnecessary current consumption even when being provided with the second hand having a large moment of inertia. The electronic clock uses a first detection mode determination circuit 112 and a second detection mode determination circuit 113 to perform the rotation detection. The electronic clock includes a determination selecting circuit 113c as changing means for changing the determination period of the second detection mode in accordance with the determination period of the first detection mode. Even when the current waveform is disturbed, erroneous determinations are prevented in a way that the determination terminal of the second detection mode is shortened if the first detection mode terminates earlier. The determination period is changed by the determination selecting circuit 113c selecting either one of a seven-time detection/determination circuit 113a that terminates the determination after seven detection pulses or a six-time detection/determination circuit 113b that terminates the determination after six detection pulses. Alternatively, instead of the number of detection pulses, a cycle of the detection pulses may be shortened. |
