| 摘要 |
PURPOSE:To obtain measured values of less cumulative errors which are automatically corrected of errors by making analog operation on the basis of the digital count values obtained in the period for the purpose of obtaining a reference measured value in correcting the characteristics such as secular change or the like of a measuring instrument. CONSTITUTION:The analog measured value outputted from a measuring instrument is applied for an input terminal 1, and is supplied to a comparator COMP via a differential amplifier DA and a buffer amplifier BA. When the moving contact (a) of a switch SW is changed to a stationary contact (b) by the signal of a control terminal 3, the period for obtaining a reference measured value starts and a D/A converter DAC is activated so that a counter CT starts counting operation. The count value is applied via the converter DAC to the comparator COMP, and when the output of the converter DAC goes equal to the reference measured value, the counter stops counting. When the contact (a) is changed to a stationary contact (c), the measured value including errors and the above-mentioned reference value of the converter DAC are applied to the input of the amplifier DA, and the measured values having no errors is transmitted to an output terminal 2. |
