Impedance analyzer using the sound card of a standard computer

The Impedance Analyzer is an instrument that measures the magnitude and phase of an electrical one-port network impedance. Linear RLC models of such impedance can be obtained as an extension. The device is a cost-effective system, easy to mount and operate. This is achieved by exploiting the resources of commercial computers with sound cards, using minimum additional hardware and digitally processing the signals intervening in the measurement. The range of frequencies to measure impedance is determined by the sound cards used, which often operate at a maximum frequency of 44kHz. This article describes the fundamentals to perform the electrical characterization and the methods used to design the system. This system was calibrated by means of a commercial RLCZ meter, a Tonghui 2826A. The estimated values of impedance were coherent with the pattern. Conclusions show that objectives were fully met, allowing for future enhancements.