数字仪表开关电源供电的干扰抑制

数字仪表因其使用方便、功能强大、显示直观等原因，得到了越来越广泛的应用。为了进一步缩小体积，需要用开关电源取代线性电源对数字仪表供电。数字仪表具有很高的精度和灵敏度，对外界的干扰也十分敏感。文中介绍了数字仪表要用开关电源供电以后出现的干扰现象，分析了干扰产生的根源和传输途径，针对性地采取了电磁干扰抑制措施，有效地消除了干扰，使系统的可靠性和抗干扰能力得到了提高。

A Method for Suppressing Interference of Switching Power Supplied Digital Meter

Digital meter is widely used because of its convenience, powerful functions and its intuitionistic. In order to be smaller, it is necessary to replace the linear power supply with switching power supply in the digital meter. Because of the high accuracy and sensitivity of the digital meter, it is apt to be interfered. In this paper, the phenomena of digital meter being interfered will be introduced after it used the switching power supply instead of the traditional linear power supply. The interference sources and its spreading path are analyzed, according to which the measures are taken to suppress the interference. Therefore, the reliability and anti-interference performance of the system are much improved.