Low-ripple output interface circuit for electrical conductivity measurement

Abstract

In this paper, an interface circuit for measuring the electrical conductivity of electrolyte solution is dcscribcd. It consists of a quadrature oscillator, a non-Inverting amplifier, a voltage-to-current converter, a peak detector, a sample-and-hold circuit, and the designed control signal generator. The proposed technique is based on the use of peak-and-hold method to detect the amplitude of sinusoidal output signal instead of the traditional method that uses the rectifier circuit connected with low-pass filter. The proposed circuit provides the obtained output in the form of DC voltage with Low ripple and fast response. Experimental results verifying the circuit performance are agreed with the theoretical values.