长距离CAN传输PCB替代传统电缆线的应用分析

Application Analysis of Long Disance CAN Transmission PCB Replacing Traditional Cable

为了解决实际工程应用中CAN总线用PCB作为传输介质时实际传输距离远远达不到40 m的问题,该文对ACK应答机制、传输距离和介电常数关系进行了分析,总结了CAN总线对时序和信号质量方面的要求,并通过PCB材料的选型、铜箔厚度的设计找到增加传输距离的方法,实测结果表明,该措施可靠、有效,有很好的应用价值。

In order to solve the problem that the actual transmission distance is far less than 40 m when can bus uses PCB as transmission medium in practical engineering application.This paper analyzes the response mechanism of ACK,the relationship between transmission distance and dielectric constant,summarizes the requirements of CAN bus on timing and signal quality,and finds a method to increase transmission distance through two measures of PCB material selection and copper foil thickness design.The test results show that the measures are accurate and reliable,with good application value.