| 摘要 |
PURPOSE:To enable the determent of output of a switch signal for a slight external force against a clock case, by discriminating the level of an output signal of a sensor circuit. CONSTITUTION:A clock has a sensor circuit composed of a clock circuit 40 and a circuit holding an electromotive voltage signal generated from a piezoelectric element 33 by an external force applied to a clock case 31. The clock is further composed of a first timer circuit 41 starting an operation in response to an output signal of the sensor circuit, a circuit 48 discriminating the level of an output signal of the sensor circuit, a second timer circuit 42 operating in accordance with the result of the circuit 48, and a switch signal generating circuit 43 outputting a switch signal for controlling the circuit 40. After the time-up of the circuit 41 starting the operation in response to the signal from the sensor circuit, the level of the output signal of the sensor circuit is discriminated, and the switch signal of the switch signal generating circuit 43 is outputted to the circuit 40 when the level of said output signal is H, while the level of a voltage of the holding circuit of the sensor circuit is made to be L for a prescribed time after the circuit 42 starts the operation. By this constitution, the suppression on the switch signal of a slight external force against the clock case is enabled. |
