Sensors are common electronic products in daily life, and the stability of their power supply is important. In electromagnetic interference (EMI), electromagnetic signals interfere with sensors, which in severe cases may reduce the accuracy of the sensor measurement. We use snubbers to suppress the electromagnetic interference so that the sensors can operate under stable conditions. As the energy source of electrical operations, a power supply is essential in every electronic system. Direct current (DC) provides the main internal operating power in commonly used electronic products. In this paper, the DC voltage converter (switching buck) is described, which can lead to a more stable DC voltage to increase the operation stability, lifetime, and reliability of electronics. The results of this study can be used to design electronic systems that are more stable and reliable and to extend the life of systems with a DC power supply. This study also leverages the positive effects of a snubber on circuits while having little effect on the overall circuit, even with the addition of electric circuits. By using different resistances and capacitances to conduct experiments on actual products and comparing the results, a buffer circuit was optimized for different needs to remove its negative effects. This approach enables designers to optimize snubber circuits for different circuit requirements. Furthermore, detailed experiments and analyses of snubber circuits provide an understanding of the importance of power supplies in electrical circuits and establish a basis for future improvements and developments. Moreover, the near-field radiation, EMI, and eye pattern are investigated for electronic countermeasures. The analysis provides not only qualitative discussion but also quantitative research. These results are helpful and useful for circuit designers.