| 摘要 |
PURPOSE:To linearize the change of the output displacement quantity of a nonlinear characteristic element for the change of a control voltage, by driving this element by an impedance changing means whch changes the impedance in the relation of inverse proportion to the characteristics of this element. CONSTITUTION:An impedance changing circuit 8 which changes the impedance in the relation of inverse proportion to the output displacement quantity of a nonlinear characteristic element 5 for a control voltage in accordance with the increment of the control voltage is interposed between one input terminal + of an operational amplifier 3 and an input terminal 1. When the control voltage inputted to the input terminal 1 is increased, transistors 82a, 82b-82n of the impedance changing circuit 8 are conductive successively to switch the impedance, and the amplification degree of an amplifying circuit consisting of the operational amplifier 3 and a resistor 4 and the control voltage have a relation shown by a polygonal line, and outputs different in amplification degree are given to the nonlinear characteristic element 5, and thus, the output displacement quantity is changed linearly for the control voltage. |
