| 摘要 |
PURPOSE:To obtain the division circuit which has linearity improved by converting an input signal voltage into a current and using a negative feedback type input amplifying circuit. CONSTITUTION:A 1st input signal Va is converted by a 1st conversion resistance 28 with a resistance value R3 into a current Va/R3, which is supplied to a 1st amplifying circuit 29. At this time, the negative input terminal of a 1st negative feedback amplifying circuit 30 is connected to the negative input terminal of the 1st amplifying circuit 29 and the positive input terminal of the 1st negative feedback amplifying circuit 30 is grounded, so the negative input terminal of the 1st amplifying circuit 29 is grounded virtually through negative feedback operation to improve the voltage-current conversion accuracy greatly, thereby improving the linearity. Then an output current having linearity improved appears at the output terminal of the 1st amplifying circuit 29. An output current having linearity improved similarly is obtained as to a 2nd input signal Vb. Consequently, the input dynamic range can be expanded and the linearity of the whole circuit is improved. |
