基于LVDS的高精度采集系统的设计

Design of High Precision Data Acquisition System Based on LVDS

在航空航天领域,为了实现对飞行器上所搭载的传感器信号的采集和传输,必须满足高精度和高可靠性的要求。由于飞行器舱内噪声环境复杂,各通道间容易出现信号串扰。针对高精度的测量要求,设计了以LVDS为通信传输的压力数据采集系统。该系统以分为采集和传输两大部分,采集模块搭建了限流保护电路和高精度的调理电路,并设计了16倍过采样的时序。传输模块以LVDS作为接收和发送单元,在保证传输稳定性的前提下提高总线码速率。经过功能仿真验证分析,所设计的采集系统受噪声影响大大降低,且传输速率不低于240 Mbit/s,采集系统的信噪比不低于77 dB。

In the aerospace field,in order to realize the acquisition and transmission of sensor signals carried on aircraft,the requirements of high precision and reliability must be meet.Due to the complex noise environment in the aircraft cabin,signal crosstalk is easy to occur between channels.According to the requirements of high-precision measurement,a pressure data acquisition system based on LVDS is designed.The system is divided into two parts i.e.,acquisition and transmission.A current limiting protection circuit and a high-precision conditioning circuit are built,and a 16 times oversampling sequence is designed.LVDS is used as the receiving and sending unit for the transmission module to improve the bus code rate on the premise of ensuring the transmission stability.After functional simulation and analysis,the influence of noice to the designed acquisition system is greatly reduced,the transmission rate is not less than 240 Mbit/s,and the signal-to-noise ratio of the acquisition system is not less than 77 dB.