| 摘要 |
PURPOSE:To obtain output reduced in an error, by forming an amplifier into two stages and providing a filter circuit equipped with a condenser between two stages. CONSTITUTION:When acceleration acts on a semiconductive sensor, stress acts on a diaphragm part by the inertia of the free end 12c and wt. 12b of a cantilever 12 to deform said diaphragm part. Each diffusion resistor 12e changes in its resistance value by piezoelectric effect due to the action of said stress. Whereupon, since the resistance value of each arm of a bridge circuit 10 changes, the voltage change proportional to the change in the resistance value is generated at both detection terminals of the circuit 10. This voltage change is operated and amplified by a differential amplifying part 20. The output of the differential amplifying part is applied to a filter part 30 and the DC component of the temp. drift of each diffusion resistor and the offset drift of the amplifying part 20 is removed by a condenser C and a resistor R7 and the electromotive force of a constant voltage source E1 is added as the DC component and further amplified by an amplifying part 40 to be outputted. By this method, output reduced in an error is obtained. |
