A Precision Low-Phase-Noise QCM Sensor Driving System With Parasitic Capacitance Compensation Technique

This letter presents a precision low-phase-noise quartz crystal microbalance (QCM) sensor driving system with parasitic capacitance compensation technique. The proposed QCM sensor driver application-specific integrated circuit (ASIC) can accurately drive QCM sensors and generate a precise resonance frequency output. The ASIC consists of a first low-pass filter (LPF), a high-speed transimpedance amplifier, and a second LPF to form a self-sustained oscillator. To achieve low phase noise and a high Q-factor, the driver integrated circuit (IC) incorporates a parasitic capacitance compensation technique. The complete driving system includes a custom printed circuit board (PCB), a microcontroller unit (MCU) evaluation board, and an organic light-emitting diode (OLED) display panel. The QCM sensor is driven by the proposed IC mounted on a custom-designed PCB. The output frequency is measured through the driver IC evaluation board, and the resulting resonance signal is acquired by the MCU. The output frequency is then displayed on the OLED panel via the MCU's serial peripheral interface communication. The system can be realized in a compact form factor without requiring bulky measurement equipment. The proposed driver IC is fabricated using a 0.18-µm complementary metal–oxide–semiconductor process, occupying a total area of 0.801 mm2. The fabricated IC consumes 5 mA of current at a 1.8 V supply. The measured system performance demonstrates a low phase noise of −103.9 dBc/Hz and a high Q-factor of 45 535.