| 摘要 |
PURPOSE:To simplify the constitution of the subject rectifying circuit by a method wherein a part of the input resistance and the setting resistance of an omverted amplifier are commonly used. CONSTITUTION:In the case when the input where an input terminal 31 is positive against an input terminal 32, as the virtual zero point of an inverted input terminal located on an arithmetic operational amplifier 36 is maintained, the voltage ei of the point of connection of a variable resistor 33 and a resistor 34 is worked out as shown by the formulaI, if the input voltage is ei<+>, the resistance value of the variable resistor 33 is R3 and the resistance value of the resistor 34 is R4, and on the other hand, the output of an arithmetic operational 37 os deflected to positive, the potential of the inverted input termianl and a non-inverted input terminal is equalized, and an output voltage e0<+>=e1' is obtained. In the case of an input having the input terminal 32 as positive against the input terminal 31, the output of the arithmetic operational amplifier 36 is deflected to positive, and as the virtual zero point is maintained, the output voltage e0<-> is worked out as shown by the formula II, if the resistance value of the resistor 35 is R5. On the other hand, as a negative signal is inputted to the non-inverted input terminal of the arithmetic operational amplifer 37 and a positive output voltage e0 is inputted to the enverted input terminal, output voltage e0<-> is worked out as shown by the formula III, if R4=R5, and a positive voltage is obtained irespective of the polarity of the input signal. |
