| 摘要 |
PURPOSE:To prevent malfunction by feeding back an output of a JKFF to a time constant circuit in a synchronizing type chattering preventing circuit comprising the time constant circuit, a Schmitt trigger and the JKFF. CONSTITUTION:Two time constant circuits comprising respectively a capacitor C1, a resistor R2 and a capacitor C2, a resistor R3 are connected to two fixed terminals of a changeover switch 1, and each output is applied to a J and a K input terminals of a JKFF4 via Schmitt trigger circuits 2, 3. The output of the JKFF4 is fed back to the time constant circuit via inverters 5, 6 and diodes D1, D2. When a moving piece of the switch 1 is connected to a lower side fixed terminal, a potential at a point A is increased gradually and a potential at a point B is decreased rapidly. The Schmitt trigger circuit 3 is inverted by the decrease in the potential at the point B and the JKFET4 is operated, then the time constant circuit is charged rapidly via the diode D1 and the Schmitt trigger circuit 2 is inverted. |
