| 摘要 |
PURPOSE:To improve the responsiveness of the limiting operation of a limiter circuit by storing by detecting a current or voltage in a moment when the limiting operation is performed exceeding the maximum current value or the maximum voltage value supplied to an element, and controlling a power source based on such current or voltage. CONSTITUTION:When the maximum current value Idt to perform a current limiting operation is set on a panel, a corresponding voltage is set on a DAC 18. The voltage of a DAC 2 is increased gradually, and the current on an element to be measured is increased gradually. An input port 13 detects a moment when the current on the element 20 to be measured exceeds the maximum current value Idt. The voltage of the element 20 to be measured in such moment is taken out as the output voltage of a buffer amplifier 7, and it is converted to a digital value by an ADC 17, then, it is stored in a RAM 14. Thereby, it is possible to prevent the voltage higher than the voltage value of the element 20 to be measured in the moment when the current on the DAC 2 exceeds the maximum current value Idt from being supplied to the element 20 to be measured by controlling the setting of the voltage of the DAC 2 by a microprocessor 1. |
