基于FPGA的多通道数字变换器的设计与实现

Design and implementation of multi-channel digital converter based on FPGA

针对某项目多通道信号采集的需求,设计了一种高精度、高可靠性的采集装置。系统以FPGA为控制芯片对多路传感器信号进行采集。待采集信号先通过信号调理和模拟开关滤波稳压处理,随后进行AD转换并编帧为数组形式,最后通过RS-422发送端完成对数据的上传。为了提高系统的灵活性和抗干扰能力,数字变换器采用模块化设计,由主控卡和电源卡构成。并采用SAR型模数转换器来提高采集精度。结合上位机与测试工装进行验证,经大量实验结果显示,该系统模块化稳定,采集精度优于0.5%,可达到项目需求。

According to the requirements of multi-channel signal acquisition in a project,a high-precision and high reliability acquisition device is designed.The system takes FPGA as the control chip to collect multi-channel sensor signals.The signal to be collected is first processed by signal conditioning and analog switch filtering and voltage stabilization,then AD conversion and framing into array form.Finally,the data is uploaded through RS-422 transmitter.In order to improve the flexibility and anti-interference ability of the system,the digital converter adopts modular design,which is composed of main control card and power card.SAR analog-to-digital converter is used to improve the acquisition accuracy.Combined with the host computer and test tooling,a large number of experimental results show that the system is modular and stable,and the acquisition accuracy is better than 0.5%,which can meet the needs of the project.