Özet Metin
Anahtar Kelimeler
Electronic tongue, liquid sensor, QCM, sensor array, FPGA
Özet Metin
In this study, two different measurement circuit design have been implemented. One of these circuits was implemented on an ARM-based microcontroller board which is named as STM32F4 Discovery. The other circuit was designed by using an FPGA-based board named Altera DE1 board. Both of them were tested with the clock signal at different frequencies the responses were the same at low frequencies however, it was seen that FPGA‘s measuring circuit has better results at the higher frequencies. Although the results of FPGA measurement circuit are sufficient for the QCM sensors that oscillate at 5 MHz, which are being used in our work, the circuit can be developed to operate more accurate at higher frequencies.
Anahtar Kelimeler
QCM sensor, FPGA, ARM microcontroller, frequency measurement
Özet Metin
The quartz crystal microbalance (QCM) sensors are widely used in gas and liquid measurements in the literature. These piezoelectric devices are generally coated with the sensitive material in order to increase their sensitivity to the desired compounds or elements. There are different types of coating procedures such as spin coating, airbrush, electrodeposition. In this study, we developed an automatic coating instrument based on airbrush technique. The instrument consists of an oscillator circuit which is necessary to operate QCM crystal, a control unit based on a microcontroller which is responsible for setting environmental conditions identical at each coating procedure. Moreover, it measures the crystal oscillating frequency during coating. The ability to prepare the same coating every time makes the sensor production reproducible which is very critical for sensor applications can be achieved by the developed instrument.
Anahtar Kelimeler
QCM crystal, airbrush, coating, oscillator circuit
Özet Metin
Anahtar Kelimeler
Özet Metin
Anahtar Kelimeler
Elektronik dil, sıvı sensörü, QCM, sensör dizisi, FPGA