| 摘要 |
<p>PURPOSE:To exactly execute a detection of seating or non-seating irrespective of whether the capacitance is large or small or a temperature variation of the periphery by detecting seating or non-seating in the case a variation quantity at every prescribed time detected by a variation quantity detecting circuit for an electric signal exceeds a threshold set in advance. CONSTITUTION:By seating, an output voltage of a detecting circuit 102 rises to a voltage V2 from a voltage V1, and a positive and roughly pulsative signal S1 is outputted from a differentiating circuit 2, and inputted to an inverter 3. When the signal of this inverter 3 exceeds its threshold, a low level signal S2 is outputted as an output signal. This level signal S2 is inputted and set to a set side 6a of an RS/FF 6 and a seating signal S3 of a high level is outputted from a set side output terminal 6c. Subsequently, when seating is shifted to non-seating, the voltage drops to V1 from V2 and a negative signal S4 is outputted from the differentiating circuit 2 and converted to a positive signal by a phase inverting circuit 4, and thereafter, inputted to an inverter 5, and by an L level signal S5, a non-seating signal S6 is outputted from a reset terminal 6b and a set side output terminal 6c.</p> |
