| 摘要 |
PURPOSE:To equaly change a comparison voltage at positive and negative sides only with one comparison voltage setting, by setting a center voltage of a voltage comparator once. CONSTITUTION:Short-circuit stage is formed by short-circuiting comparison voltage measuring terminals 7 and 8 with a clip (not shown) or driving a slider of a variable resistor 22 for comparison voltage width setting counterclockwise, and a voltage between measuring terminals 7 and 8 or 8 and 9 is set to a center voltage of the voltage comparator, e.g. to zero volt by driving a slider of a variable resistor 21 for the center voltage setting. Further, the chip is removed in the case of the former and the slider of the resistor 22 is driven in the case of the latter to measure a voltage between the terminals 7 and 8, i.e. compared voltage width, and a half of a voltage between the terminals 7 and 8 is taken as the comparison voltage of positive and negative sides respectively by taking the center voltage at a center. |
