Abstract: High-field asymmetric waveform ion mobility spectrometry (FAIMS) is a chemical analytical technique that utilizes the difference in ion mobility of ions at alternating high-low electric field strengths for ion separation. FAIMS has the advantages of working at atmospheric pressure, easy on-site detection and high portability. High voltage RF pulse power supply is the core component of FAIMS, which will directly affect the sensitivity and resolving power. In order to give full play to the dispersion mechanism of FAIMS, a high-voltage RF square-wave power supply was designed based on a half-bridge topology circuit using a new generation of high-voltage super junction metal oxide semiconductor field effect transistor (SJ MOS) as the core device of the power supply. The measurements showed that the output waveform of the power supply is close to an ideal square wave, with a peak-to-peak value of 506 V, a frequency of 1 MHz, and a power consumption of only 29 W. The power supply was combined with the house-made FAIMS core system to detect the gas samples such as acetone and methyl salicylate. Based on this system, the relationship between the resolving power and sensitivity of FAIMS and the amplitude of the separation voltage, the frequency of the power supply and the flow rate of the carrier gas were studied. The results showed that increasing the dispersion power supply amplitude significantly improves the FAIMS resolving power with a large loss of sensitivity, increasing the power supply frequency effectively improves the sensitivity with a slight loss of FAIMS resolving power. When the frequency is raised to 1 MHz, the peak height of methyl salicylate increases to 228% of that at 400 kHz, while the resolving power decreases to only 89% of that at 400 kHz. In addition, increasing the carrier gas flow rate also improves the sensitivity, but with a corresponding loss of resolving power. This study demonstrated the reciprocal trade-off between the resolving power and sensitivity of FAIMS. Therefore, when selecting FAIMS parameters, these two key performance indicators must be considered comprehensively, which also provides a reference for the optimization of FAIMS. The FAIMS dispersion power supply designed in this work is characterized by high voltage and high frequency output, good waveform quality and low power consumption, which can stably support FAIMS for ion selection and dispersion, and is of practical value for the development of FAIMS miniaturization and field detection.