| 摘要 |
PROBLEM TO BE SOLVED: To provide a capacitance type sensor capable of obtaining digital output, without such a correction as linearity correction by detecting physical quantity change as capacitance change. SOLUTION: The capacitance type sensor 1 includes a first capacitor 2a detecting the change of physical quantity as a capacitance change, a second capacitor 2b which is to be a differential capacitor together with the first capacitor, a discharge means for accumulating electric charge to be the sum of electric charges, accumulated in the second capacitor and the first capacitor in a third capacitor 31 and repeatedly discharging the electric charge of the difference between the first capacitor charge and the second capacitor charge out of the charge accumulated in the third capacitor, a detection signal outputting means 4 for outputting a detection signal, when the charge in the third capacitor lowered a specific value as the results of the discharge with the discharge means, and a calculation means 7, counting the detection signals for a certain period and calculating physical quantity, based on the signal counts.
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