Voltage absolute value circuit

Abstract

The invention discloses a voltage absolute value circuit. The voltage absolute value circuit comprises a comparator U1, a comparator U2, a diode D1, a capacitor C1, a resistor R1 and a potentiometer RP1, wherein one end of the resistor R1 is connected with a resistor R2 and an input signal Vi respectively; the other end of the resistor R1 is connected with a resistor R3, a negative electrode of the diode D1 and an inverse-phase end of the comparator U1; the inverse-phase end of the comparator U1 is connected with the grounded potentiometer RP1; an output end of the comparator U1 is connected with a positive electrode of the diode D1 and the negative electrode of a diode D2 respectively; the positive electrode of the diode D2 is connected with the other end of the resistor R3 and a resistor R6; the other end of the resistor R6 is connected with the inverse-phase end of the comparator U2, a resistor R4 and a resistor R5. According to the voltage absolute value circuit, two capacitors are used as main control elements and are matched with a capacitance resistance element, so that a signal phase can be corrected and the precision of the circuit is improved; the circuit is simple in structure, low in cost and small in size and has a wide applicable range.

Description

technical field [0001] The invention relates to an analog circuit, in particular to a voltage absolute value circuit. Background technique [0002] In the circuit control system, the AC signals of various circuits have negative signal components. In the specific use process, the negative signal part needs to be changed into a positive signal first, that is, a voltage absolute value circuit needs to be added to make the output signal the absolute value of the input signal. Or directly proportional to the absolute value; the most commonly used voltage absolute value circuit in the prior art is to directly use a rectifier, this method is simple and easy, but due to the forward voltage drop of the rectifier, it is impossible to obtain high-precision absolute In addition, the use of dedicated chips for sampling is expensive; at the same time, the signal entering the voltage absolute value circuit often has serious interference during electrical signal transmission, which affects ...

AI Technical Summary

Problems solved by technology

[0002] In the circuit control system, the AC signals of various circuits have negative signal components. In the specific use process, the negative signal part needs to be changed into a positive signal first, that is, a voltage absolute value circuit needs to be added to make the output signal the absolute value of the input signal. Or directly proportional to the absolute value; the most commonly used voltage absolute value circuit in th

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