Impedance Measurement of the Quartz Crystal Microbalance using Phase Gain Detector and Digital Storage Oscilloscope

Abstract

Quartz Crystal Microbalance (QCM) sensor responds measurement can be done in three different methods. One method which gives a rich information is the impedance measurement of the QCM sensor using a phase gain measurement. In this configuration, the QCM sensor was placed in a configuration where the sensor was injected with a sinusoidal signal. Signal gain and phase difference between the signal before and after the QCM sensor was measured and compared. An integrated circuit which able to measure the gain and phase difference is available in a low cost and small footprint. In other hand, the high-performance digital oscilloscope is also available in the market with reasonably priced. In this experiment, we comparing the use of the AD8302, gain and phase detector circuit, and Picoscope 5244B. Picoscope 5244B is a high-performance Digital Storage Oscilloscope (DSO). The result showed that the AD8302 gave an easy and direct results of the gain and phase value. The output can directly processed using a microcontroller which allow for the development of a gain and phase detection system. In other hand, the DSO provided a true signal comparison between the input signal and output signal, but it required a complex processing.