Development of an automated system for measuring electrical impedance

The measurement of electrical impedance is a common procedure in physics laboratories. Conventionally, by means of voltage measurements a voltage divider circuit can determine the electrical impedance of any device. However, this procedure allows the impedances can be measured only in limited ranges of values. In components as some piezoelectric transducers, which have large impedance magnitude band, the results obtained with this procedure are not satisfactory. This paper presents a simple electronic circuit, low cost, easy to understand operation by students with low knowledgement in electronics and broadens the range of determination of impedances. The system was tested with piezoelectric transducers and the results compared with a commercial impedance analyzer. The results have shown that it is possible to measure impedances between tens of $\mathrm{\Omega }$ and tens of k$\mathrm{\Omega }$ satisfactorily.

Keywords:
LabView; Piezoelectric; Electronic Circuit