| 摘要 |
PURPOSE:To obtain a pulse of stable crest value, simplify a circuit configuration and obtain a linear conversion characteristic by controlling LC oscillation circuit with the use of a counter. CONSTITUTION:A physical displacement is converted to an electric signal at a detection part SD and a voltage prearranged current signal is output through a compensation part 1D and an output part OT. A movable electrode MP between fixed electrodes SP1 and SP2 at SD moves according to a physical displacement, resulting in the differential change of electrostatic capacities C1, C2 and the connection to LC- type oscillation circuit OSC of C1 and C2 through a switch SW. An output from OSC is given to a counter CT and SW is changed over at an output from CT. Following this process, the duty ratio of an output from CT corresponds to C1 and C2 and a detection error based on an ambient temperature change, etc. is eliminated. |
