The division circuit for ratio calculation

Published:2011/7/14 23:04:00 Author:Fiona | Keyword: ratio calculation | From:SeekIC

Circuit function This circuit is the division circuit that the input signal Z is divided by X. Besides operating EO = 10Z / (-X) and calculating the ratio or percentage,it also can be used as AGC amplifier (A=1/X） which inputs control voltage from the X side. But it can't do large-scale operations. If the input X as the denominator turns smaller, 1 / X will increase,.When X = 0, the gain is infinite, so for division, the range is limited. Circuit work If the IC is used as a multiplication, the output voltage feedbacks to the Y input, does the 1 / X calculation, and then multiplies by Z. Because of adding a multiplication unit in the OP amplifier feedback loop, the X input turns smaller so that the circuit would become unstable. and the X values ​​are different, closed-loop frequency characteristics will change because of X's different values. Pay attention to use it. Z-ended input signal has been inverted in the output, the X input only can use the negative voltage . When X = 10V,the circuit uses VR2 to adjust scaling factor to make A = 1. It also can use VR2 to do disorders adjustment of dynamic range of the division circuit.After reducing the variable range, in order to facilitate adjustment, it addsvoltage divider circuit composed of the R1, R2. Input 1V from Z,input 1V from X, adjust VR1 to make the output to be -10V (A =- 10).when Z = 0.1V, X =- 0.1V,it also can get 10V output, but it can not guarantee the accuracy and stability Degrees. In addition, the frequency response changes with the value which is inputed from X.This point also should be noted.



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