Novel Remote Measurement Technique Using Resistive Sensor as Grounded Load in an Opamp Based V-to-I Converter

This letter presents a simple and low-cost remote measurement technique, which consists of two almost identical diodes along with a resistive sensor as grounded load in an operational amplifier based conventional voltage to current converter. For a square wave input to the circuit, the mean value of the circuit output waveform that is measured with a digital storage oscilloscope is linearly proportional with the sensing resistance. This straightforward technique is not only independent of lead resistances but also compensates the effect of ambient temperature variation. The experimental results corroborate the theoretical assumptions.