A Low Cost Impedance Measurement Method for Integrated Circuits

Impedance matching of a Radio Frequency (RF) device antenna with its integrated circuit chip is necessary to improve efficiency and RF communication quality. This matching can only be done if one knows the chip components impedances. This paper presents a new RFmeasurement method to determine electrical characteristics like s-parameters or impedance of smart cards integrated circuits or antennas, using common measurement devices as a computer, an oscilloscope or any voltage acquisition device, and a directional coupler. Achieved results are compared with vector network analyzer (VNA) measurements and the method is applied to real contactless integrated circuit proximity cards components.