高速高精度数字系统的电磁兼容设计  

Design of EMC for High-speed and High-precision Digital System

作　　者：陈莉[1] 王跃科[1] 张传胜[1] 

机构地区：[1]国防科学技术大学,湖南长沙410073

出　　处：《计算机测量与控制》2008年第4期544-545,548,共3页Computer Measurement &Control

摘　　要：针对高速、高精度数字系统对电磁兼容性的严格要求,分析了系统电源、地的重要性以及影响高速模数转换器(ADC)和数模转换器(DAC)电路性能的主要因素;在设计印刷电路板时,采用隔离数字部分与模拟部分、抑制地弹噪声等方法优化系统电源,通过改善ABC、DAC电路的供电方式、优化采样时钟和高速数字信号线来提高系统抗电磁干扰的能力;并比较了一个失败案例和一个成功案例,后者较前者带外抑制指标提高约15dB,表明采用所述方法可以有效改善数字系统的电磁兼容性。EMC （electromagnetic compatibility） problem should be taken special attention to in high-speed and high-precision application of digital system. This paper recommends some methods to improve the performance of digital system when designing printed circuit board （PCB）. The methods refer to optimizing the power supply circuit, controlling the ground bounce noise and meliorating the electromagnetic condition of ADC ＆ DAC circuit. A comparison of an unsuccessful case and a successful case is presented in the end, which shows that the EMC of digital system can be effectively ameliorated with the methods.

关 键 词：电磁兼容性 数字系统 印刷电路板 地弹噪声 

分 类 号：TN919[电子电信—通信与信息系统]