| 摘要 |
PURPOSE:To remove influence of noise from a chopper device for electric power by a method wherein a rectangular wave signal to be outputted according to comparison between an acceleration command voltage and a sawtooth wave signal is delayed for the prescribed time, and is outputted. CONSTITUTION:When the sawtooth wave signal (a) sent from a oscillating circuit 15 intersects the acceleration command voltage (b), a comparator 13 sends out an output to make a transistor T2 to be in OFF condition. As a result, a capacitor C21 starts charging as shown by (d), and a transistor TR21 is not made to be in ON condition at once. When electric potential at the node C becomes to High, and moreover after lapse of time t1 when the capacitor C21 is charged up to the Schmitt circuit level, a transistor TR1 is made to be in OFF condition, and a transistor TR2 is made to be in OFF condition to make the chopper circuit 5 to be in OFF condition. Accordingly an inside transistor T1 is not made to be in ON condition even when noise as shown by N on the voltage (b) is applied, and erroneous operation is not generated. |
