The Hall sensor has the advantages of wide measurement range, fast response speed, high measurement accuracy, good linearity, good dynamic performance, wide operating frequency range, high reliability, strong overload capacity, and large measurement range,etc. The differential hall effect sensor is small in size, light in weight and easy to install. Due to its advantages, it can be widely used in frequency conversion speed control devices, inverter devices, UPS power supplies, inverter welding machines, electrolytic plating, CNC machine tools, microcomputer monitoring systems, power grid monitoring systems and various fields that require isolation and detection of current and voltage .